Programs & Examples On #Aim

AOL Instant Messenger (AIM) is an instant messaging and presence computer program.

OpenCV TypeError: Expected cv::UMat for argument 'src' - What is this?

This is a general error, which throws sometimes, when you have mismatch between the types of the data you use. E.g I tried to resize the image with opencv, it gave the same error. Here is a discussion about it.

FlutterError: Unable to load asset

In my case a restart didn't help. I had to uninstall the app and then run everything again. It did worked!

Pandas Merging 101

This post aims to give readers a primer on SQL-flavored merging with pandas, how to use it, and when not to use it.

In particular, here's what this post will go through:

  • The basics - types of joins (LEFT, RIGHT, OUTER, INNER)

    • merging with different column names
    • merging with multiple columns
    • avoiding duplicate merge key column in output

What this post (and other posts by me on this thread) will not go through:

  • Performance-related discussions and timings (for now). Mostly notable mentions of better alternatives, wherever appropriate.
  • Handling suffixes, removing extra columns, renaming outputs, and other specific use cases. There are other (read: better) posts that deal with that, so figure it out!

Note
Most examples default to INNER JOIN operations while demonstrating various features, unless otherwise specified.

Furthermore, all the DataFrames here can be copied and replicated so you can play with them. Also, see this post on how to read DataFrames from your clipboard.

Lastly, all visual representation of JOIN operations have been hand-drawn using Google Drawings. Inspiration from here.



Enough Talk, just show me how to use merge!

Setup & Basics

np.random.seed(0)
left = pd.DataFrame({'key': ['A', 'B', 'C', 'D'], 'value': np.random.randn(4)})    
right = pd.DataFrame({'key': ['B', 'D', 'E', 'F'], 'value': np.random.randn(4)})
  
left

  key     value
0   A  1.764052
1   B  0.400157
2   C  0.978738
3   D  2.240893

right

  key     value
0   B  1.867558
1   D -0.977278
2   E  0.950088
3   F -0.151357

For the sake of simplicity, the key column has the same name (for now).

An INNER JOIN is represented by

Note
This, along with the forthcoming figures all follow this convention:

  • blue indicates rows that are present in the merge result
  • red indicates rows that are excluded from the result (i.e., removed)
  • green indicates missing values that are replaced with NaNs in the result

To perform an INNER JOIN, call merge on the left DataFrame, specifying the right DataFrame and the join key (at the very least) as arguments.

left.merge(right, on='key')
# Or, if you want to be explicit
# left.merge(right, on='key', how='inner')

  key   value_x   value_y
0   B  0.400157  1.867558
1   D  2.240893 -0.977278

This returns only rows from left and right which share a common key (in this example, "B" and "D).

A LEFT OUTER JOIN, or LEFT JOIN is represented by

This can be performed by specifying how='left'.

left.merge(right, on='key', how='left')

  key   value_x   value_y
0   A  1.764052       NaN
1   B  0.400157  1.867558
2   C  0.978738       NaN
3   D  2.240893 -0.977278

Carefully note the placement of NaNs here. If you specify how='left', then only keys from left are used, and missing data from right is replaced by NaN.

And similarly, for a RIGHT OUTER JOIN, or RIGHT JOIN which is...

...specify how='right':

left.merge(right, on='key', how='right')

  key   value_x   value_y
0   B  0.400157  1.867558
1   D  2.240893 -0.977278
2   E       NaN  0.950088
3   F       NaN -0.151357

Here, keys from right are used, and missing data from left is replaced by NaN.

Finally, for the FULL OUTER JOIN, given by

specify how='outer'.

left.merge(right, on='key', how='outer')

  key   value_x   value_y
0   A  1.764052       NaN
1   B  0.400157  1.867558
2   C  0.978738       NaN
3   D  2.240893 -0.977278
4   E       NaN  0.950088
5   F       NaN -0.151357

This uses the keys from both frames, and NaNs are inserted for missing rows in both.

The documentation summarizes these various merges nicely:

enter image description here


Other JOINs - LEFT-Excluding, RIGHT-Excluding, and FULL-Excluding/ANTI JOINs

If you need LEFT-Excluding JOINs and RIGHT-Excluding JOINs in two steps.

For LEFT-Excluding JOIN, represented as

Start by performing a LEFT OUTER JOIN and then filtering (excluding!) rows coming from left only,

(left.merge(right, on='key', how='left', indicator=True)
     .query('_merge == "left_only"')
     .drop('_merge', 1))

  key   value_x  value_y
0   A  1.764052      NaN
2   C  0.978738      NaN

Where,

left.merge(right, on='key', how='left', indicator=True)

  key   value_x   value_y     _merge
0   A  1.764052       NaN  left_only
1   B  0.400157  1.867558       both
2   C  0.978738       NaN  left_only
3   D  2.240893 -0.977278       both

And similarly, for a RIGHT-Excluding JOIN,

(left.merge(right, on='key', how='right', indicator=True)
     .query('_merge == "right_only"')
     .drop('_merge', 1))

  key  value_x   value_y
2   E      NaN  0.950088
3   F      NaN -0.151357

Lastly, if you are required to do a merge that only retains keys from the left or right, but not both (IOW, performing an ANTI-JOIN),

You can do this in similar fashion—

(left.merge(right, on='key', how='outer', indicator=True)
     .query('_merge != "both"')
     .drop('_merge', 1))

  key   value_x   value_y
0   A  1.764052       NaN
2   C  0.978738       NaN
4   E       NaN  0.950088
5   F       NaN -0.151357

Different names for key columns

If the key columns are named differently—for example, left has keyLeft, and right has keyRight instead of key—then you will have to specify left_on and right_on as arguments instead of on:

left2 = left.rename({'key':'keyLeft'}, axis=1)
right2 = right.rename({'key':'keyRight'}, axis=1)

left2
 
  keyLeft     value
0       A  1.764052
1       B  0.400157
2       C  0.978738
3       D  2.240893

right2

  keyRight     value
0        B  1.867558
1        D -0.977278
2        E  0.950088
3        F -0.151357
left2.merge(right2, left_on='keyLeft', right_on='keyRight', how='inner')

  keyLeft   value_x keyRight   value_y
0       B  0.400157        B  1.867558
1       D  2.240893        D -0.977278

Avoiding duplicate key column in output

When merging on keyLeft from left and keyRight from right, if you only want either of the keyLeft or keyRight (but not both) in the output, you can start by setting the index as a preliminary step.

left3 = left2.set_index('keyLeft')
left3.merge(right2, left_index=True, right_on='keyRight')
    
    value_x keyRight   value_y
0  0.400157        B  1.867558
1  2.240893        D -0.977278

Contrast this with the output of the command just before (that is, the output of left2.merge(right2, left_on='keyLeft', right_on='keyRight', how='inner')), you'll notice keyLeft is missing. You can figure out what column to keep based on which frame's index is set as the key. This may matter when, say, performing some OUTER JOIN operation.


Merging only a single column from one of the DataFrames

For example, consider

right3 = right.assign(newcol=np.arange(len(right)))
right3
  key     value  newcol
0   B  1.867558       0
1   D -0.977278       1
2   E  0.950088       2
3   F -0.151357       3

If you are required to merge only "new_val" (without any of the other columns), you can usually just subset columns before merging:

left.merge(right3[['key', 'newcol']], on='key')

  key     value  newcol
0   B  0.400157       0
1   D  2.240893       1

If you're doing a LEFT OUTER JOIN, a more performant solution would involve map:

# left['newcol'] = left['key'].map(right3.set_index('key')['newcol']))
left.assign(newcol=left['key'].map(right3.set_index('key')['newcol']))

  key     value  newcol
0   A  1.764052     NaN
1   B  0.400157     0.0
2   C  0.978738     NaN
3   D  2.240893     1.0

As mentioned, this is similar to, but faster than

left.merge(right3[['key', 'newcol']], on='key', how='left')

  key     value  newcol
0   A  1.764052     NaN
1   B  0.400157     0.0
2   C  0.978738     NaN
3   D  2.240893     1.0

Merging on multiple columns

To join on more than one column, specify a list for on (or left_on and right_on, as appropriate).

left.merge(right, on=['key1', 'key2'] ...)

Or, in the event the names are different,

left.merge(right, left_on=['lkey1', 'lkey2'], right_on=['rkey1', 'rkey2'])

Other useful merge* operations and functions

This section only covers the very basics, and is designed to only whet your appetite. For more examples and cases, see the documentation on merge, join, and concat as well as the links to the function specs.



Continue Reading

Jump to other topics in Pandas Merging 101 to continue learning:

* you are here

pod has unbound PersistentVolumeClaims

You have to define a PersistentVolume providing disc space to be consumed by the PersistentVolumeClaim.

When using storageClass Kubernetes is going to enable "Dynamic Volume Provisioning" which is not working with the local file system.


To solve your issue:

  • Provide a PersistentVolume fulfilling the constraints of the claim (a size >= 100Mi)
  • Remove the storageClass-line from the PersistentVolumeClaim
  • Remove the StorageClass from your cluster

How do these pieces play together?

At creation of the deployment state-description it is usually known which kind (amount, speed, ...) of storage that application will need.
To make a deployment versatile you'd like to avoid a hard dependency on storage. Kubernetes' volume-abstraction allows you to provide and consume storage in a standardized way.

The PersistentVolumeClaim is used to provide a storage-constraint alongside the deployment of an application.

The PersistentVolume offers cluster-wide volume-instances ready to be consumed ("bound"). One PersistentVolume will be bound to one claim. But since multiple instances of that claim may be run on multiple nodes, that volume may be accessed by multiple nodes.

A PersistentVolume without StorageClass is considered to be static.

"Dynamic Volume Provisioning" alongside with a StorageClass allows the cluster to provision PersistentVolumes on demand. In order to make that work, the given storage provider must support provisioning - this allows the cluster to request the provisioning of a "new" PersistentVolume when an unsatisfied PersistentVolumeClaim pops up.


Example PersistentVolume

In order to find how to specify things you're best advised to take a look at the API for your Kubernetes version, so the following example is build from the API-Reference of K8S 1.17:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: ckan-pv-home
  labels:
    type: local
spec:
  capacity:
    storage: 100Mi
  hostPath:
    path: "/mnt/data/ckan"

The PersistentVolumeSpec allows us to define multiple attributes. I chose a hostPath volume which maps a local directory as content for the volume. The capacity allows the resource scheduler to recognize this volume as applicable in terms of resource needs.


Additional Resources:

error: resource android:attr/fontVariationSettings not found

Usually it's because of sdk versions and/or dependencies.

For Cordova developers, put your dependencies settings in "project.properties" file under CORDOVA_PROJECT_ROOT/platforms/android/ folder, like this:

target=android-26
android.library.reference.1=CordovaLib
android.library.reference.2=app
cordova.system.library.1=com.android.support:support-v4:26.1.0
cordova.gradle.include.2=cordova-plugin-googlemaps/app-tbxml-android.gradle
cordova.system.library.3=com.android.support:support-core-utils:26.1.0
cordova.system.library.4=com.google.android.gms:play-services-maps:15.0.0
cordova.system.library.5=com.google.android.gms:play-services-location:15.0.0

So if you use CLI "cordova build", it will overwrite the dependencies section:

dependencies {
    implementation fileTree(dir: 'libs', include: '*.jar')
    // SUB-PROJECT DEPENDENCIES START 
   /* section being overwritten by cordova, referencing project.properties */
...
    // SUB-PROJECT DEPENDENCIES END
}

If you are using proper libraries and its versions in project.properties, you should be fine.

React Native: JAVA_HOME is not set and no 'java' command could be found in your PATH

I think the right way to find the internal Java used by the Android Studio is to

  1. Open Android Studio
  2. Go to File->Other Settings->Default Project Structure/JDK Location:
  3. and copy what ever string is specified there

This will not require memorising the folder or searching for java and also these steps wil take of any future changes to the java location by the Android Studio team changes I suppose

Is it safe to clean docker/overlay2/

also had problems with rapidly growing overlay2

/var/lib/docker/overlay2 - is a folder where docker store writable layers for your container. docker system prune -a - may work only if container is stopped and removed.

in my i was able to figure out what consumes space by going into overlay2 and investigating.

that folder contains other hash named folders. each of those has several folders including diff folder.

diff folder - contains actual difference written by a container with exact folder structure as your container (at least it was in my case - ubuntu 18...)

so i've used du -hsc /var/lib/docker/overlay2/LONGHASHHHHHHH/diff/tmp to figure out that /tmp inside of my container is the folder which gets polluted.

so as a workaround i've used -v /tmp/container-data/tmp:/tmp parameter for docker run command to map inner /tmp folder to host and setup a cron on host to cleanup that folder.

cron task was simple:

  • sudo nano /etc/crontab
  • */30 * * * * root rm -rf /tmp/container-data/tmp/*
  • save and exit

NOTE: overlay2 is system docker folder, and they may change it structure anytime. Everything above is based on what i saw in there. Had to go in docker folder structure only because system was completely out of space and even wouldn't allow me to ssh into docker container.

How to overcome the CORS issue in ReactJS

Temporary solve this issue by a chrome plugin called CORS. Btw backend server have to send proper header to front end requests.

Prevent content from expanding grid items

The previous answer is pretty good, but I also wanted to mention that there is a fixed layout equivalent for grids, you just need to write minmax(0, 1fr) instead of 1fr as your track size.

Hibernate Error executing DDL via JDBC Statement

Another sneaky issue related to this is naming your columns with - instead of _.

Something like this will trigger an error at the moment your tables are getting created.

@Column(name="verification-token")

How can I make Bootstrap 4 columns all the same height?

Equal height columns is the default behaviour for Bootstrap 4 grids.

_x000D_
_x000D_
.col { background: red; }_x000D_
.col:nth-child(odd) { background: yellow; }
_x000D_
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous">_x000D_
_x000D_
<div class="container">_x000D_
  <div class="row">_x000D_
    <div class="col">_x000D_
      1 of 3_x000D_
    </div>_x000D_
    <div class="col">_x000D_
      1 of 3_x000D_
      <br>_x000D_
      Line 2_x000D_
      <br>_x000D_
      Line 3_x000D_
    </div>_x000D_
    <div class="col">_x000D_
      1 of 3_x000D_
    </div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Hyper-V: Create shared folder between host and guest with internal network

  • Open Hyper-V Manager
  • Create a new internal virtual switch (e.g. "Internal Network Connection")
  • Go to your Virtual Machine and create a new Network Adapter -> choose "Internal Network Connection" as virtual switch
  • Start the VM
  • Assign both your host as well as guest an IP address as well as a Subnet mask (IP4, e.g. 192.168.1.1 (host) / 192.168.1.2 (guest) and 255.255.255.0)
  • Open cmd both on host and guest and check via "ping" if host and guest can reach each other (if this does not work disable/enable the network adapter via the network settings in the control panel, restart...)
  • If successfull create a folder in the VM (e.g. "VMShare"), right-click on it -> Properties -> Sharing -> Advanced Sharing -> checkmark "Share this folder" -> Permissions -> Allow "Full Control" -> Apply
  • Now you should be able to reach the folder via the host -> to do so: open Windows Explorer -> enter the path to the guest (\192.168.1.xx...) in the address line -> enter the credentials of the guest (Choose "Other User" - it can be necessary to change the domain therefore enter ".\"[username] and [password])

There is also an easy way for copying via the clipboard:

  • If you start your VM and go to "View" you can enable "Enhanced Session". If you do it is not possible to drag and drop but to copy and paste.

Enhanced Session

Error creating bean with name 'entityManagerFactory' defined in class path resource : Invocation of init method failed

Adding dependencies didn't fix the issue at my end.

The issue was happening at my end because of "additional" fields that are part of the "@Entity" class and don't exist in the database.

I removed the additional fields from the @Entity class and it worked.

Goodluck.

sudo: docker-compose: command not found

I will leave this here as a possible fix, worked for me at least and might help others. Pretty sure this would be a linux only fix.

I decided to not go with the pip install and go with the github version (option one on the installation guide).

Instead of placing the copied docker-compose directory into /usr/local/bin/docker-compose from the curl/github command, I went with /usr/bin/docker-compose which is the location of Docker itself and will force the program to run in root. So it works in root and sudo but now won't work without sudo so the opposite effect which is what you want to run it as a user anyways.

ASP.NET Core Identity - get current user

I have put something like this in my Controller class and it worked:

IdentityUser user = await userManager.FindByNameAsync(HttpContext.User.Identity.Name);

where userManager is an instance of Microsoft.AspNetCore.Identity.UserManager class (with all weird setup that goes with it).

Why do I have to "git push --set-upstream origin <branch>"?

The difference between
git push origin <branch>
and
git push --set-upstream origin <branch>
is that they both push just fine to the remote repository, but it's when you pull that you notice the difference.

If you do:
git push origin <branch>
when pulling, you have to do:
git pull origin <branch>

But if you do:
git push --set-upstream origin <branch>
then, when pulling, you only have to do:
git pull

So adding in the --set-upstream allows for not having to specify which branch that you want to pull from every single time that you do git pull.

JPA Hibernate Persistence exception [PersistenceUnit: default] Unable to build Hibernate SessionFactory

I was getting this error even when all the relevant dependencies were in place because I hadn't created the schema in MySQL.

I thought it would be created automatically but it wasn't. Although the table itself will be created, you have to create the schema.

How do I install a pip package globally instead of locally?

Are you using virtualenv? If yes, deactivate the virtualenv. If you are not using, it is already installed widely (system level). Try to upgrade package.

pip install flake8 --upgrade

Install pip in docker

While T. Arboreus's answer might fix the issues with resolving 'archive.ubuntu.com', I think the last error you're getting says that it doesn't know about the packages php5-mcrypt and python-pip. Nevertheless, the reduced Dockerfile of you with just these two packages worked for me (using Debian 8.4 and Docker 1.11.0), but I'm not quite sure if that could be the case because my host system is different than yours.

FROM ubuntu:14.04

# Install dependencies
RUN apt-get update && apt-get install -y \
    php5-mcrypt \
    python-pip

However, according to this answer you should think about installing the python3-pip package instead of the python-pip package when using Python 3.x.

Furthermore, to make the php5-mcrypt package installation working, you might want to add the universe repository like it's shown right here. I had trouble with the add-apt-repository command missing in the Ubuntu Docker image so I installed the package software-properties-common at first to make the command available.

Splitting up the statements and putting apt-get update and apt-get install into one RUN command is also recommended here.

Oh and by the way, you actually don't need the -y flag at apt-get update because there is nothing that has to be confirmed automatically.

Finally:

FROM ubuntu:14.04

# Install dependencies
RUN apt-get update && apt-get install -y \
    software-properties-common
RUN add-apt-repository universe
RUN apt-get update && apt-get install -y \
    apache2 \
    curl \
    git \
    libapache2-mod-php5 \
    php5 \
    php5-mcrypt \
    php5-mysql \
    python3.4 \
    python3-pip

Remark: The used versions (e.g. of Ubuntu) might be outdated in the future.

'dict' object has no attribute 'has_key'

has_key has been deprecated in Python 3.0. Alternatively you can use 'in'

graph={'A':['B','C'],
   'B':['C','D']}

print('A' in graph)
>> True

print('E' in graph)
>> False

Limit characters displayed in span

Yes, sort of.

You can explicitly size a container using units relative to font-size:

  • 1em = 'the horizontal width of the letter m'
  • 1ex = 'the vertical height of the letter x'
  • 1ch = 'the horizontal width of the number 0'

In addition you can use a few CSS properties such as overflow:hidden; white-space:nowrap; text-overflow:ellipsis; to help limit the number as well.

What is secret key for JWT based authentication and how to generate it?

You can write your own generator. The secret key is essentially a byte array. Make sure that the string that you convert to a byte array is base64 encoded.

In Java, you could do something like this.

String key = "random_secret_key";
String base64Key = DatatypeConverter.printBase64Binary(key.getBytes());
byte[] secretBytes = DatatypeConverter.parseBase64Binary(base64Key);

Is JVM ARGS '-Xms1024m -Xmx2048m' still useful in Java 8?

What I know is one reason when “GC overhead limit exceeded” error is thrown when 2% of the memory is freed after several GC cycles

By this error your JVM is signalling that your application is spending too much time in garbage collection. so the little amount GC was able to clean will be quickly filled again thus forcing GC to restart the cleaning process again.

You should try changing the value of -Xmx and -Xms.

Getting "error": "unsupported_grant_type" when trying to get a JWT by calling an OWIN OAuth secured Web Api via Postman

Old Question, but for angular 6, this needs to be done when you are using HttpClient I am exposing token data publicly here but it would be good if accessed via read-only properties.

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable, of } from 'rxjs';
import { delay, tap } from 'rxjs/operators';
import { Router } from '@angular/router';


@Injectable()
export class AuthService {
    isLoggedIn: boolean = false;
    url = "token";

    tokenData = {};
    username = "";
    AccessToken = "";

    constructor(private http: HttpClient, private router: Router) { }

    login(username: string, password: string): Observable<object> {
        let model = "username=" + username + "&password=" + password + "&grant_type=" + "password";

        return this.http.post(this.url, model).pipe(
            tap(
                data => {
                    console.log('Log In succesful')
                    //console.log(response);
                    this.isLoggedIn = true;
                    this.tokenData = data;
                    this.username = data["username"];
                    this.AccessToken = data["access_token"];
                    console.log(this.tokenData);
                    return true;

                },
                error => {
                    console.log(error);
                    return false;

                }
            )
        );
    }
}

filter out multiple criteria using excel vba

An option using AutoFilter


Option Explicit

Public Sub FilterOutMultiple()
    Dim ws As Worksheet, filterOut As Variant, toHide As Range

    Set ws = ActiveSheet
    If Application.WorksheetFunction.CountA(ws.Cells) = 0 Then Exit Sub 'Empty sheet

    filterOut = Split("A B C D E F G")

    Application.ScreenUpdating = False
    With ws.UsedRange.Columns("A")
        If ws.FilterMode Then .AutoFilter
       .AutoFilter Field:=1, Criteria1:=filterOut, Operator:=xlFilterValues
        With .SpecialCells(xlCellTypeVisible)
            If .CountLarge > 1 Then Set toHide = .Cells 'Remember unwanted (A, B, and C)
        End With
       .AutoFilter
        If Not toHide Is Nothing Then
            toHide.Rows.Hidden = True                   'Hide unwanted (A, B, and C)
           .Cells(1).Rows.Hidden = False                'Unhide header
        End If
    End With
    Application.ScreenUpdating = True
End Sub

JWT (Json Web Token) Audience "aud" versus Client_Id - What's the difference?

If you came here searching OpenID Connect (OIDC): OAuth 2.0 != OIDC

I recognize that this is tagged for oauth 2.0 and NOT OIDC, however there is frequently a conflation between the 2 standards since both standards can use JWTs and the aud claim. And one (OIDC) is basically an extension of the other (OAUTH 2.0). (I stumbled across this question looking for OIDC myself.)

OAuth 2.0 Access Tokens##

For OAuth 2.0 Access tokens, existing answers pretty well cover it. Additionally here is one relevant section from OAuth 2.0 Framework (RFC 6749)

For public clients using implicit flows, this specification does not provide any method for the client to determine what client an access token was issued to.
...
Authenticating resource owners to clients is out of scope for this specification. Any specification that uses the authorization process as a form of delegated end-user authentication to the client (e.g., third-party sign-in service) MUST NOT use the implicit flow without additional security mechanisms that would enable the client to determine if the access token was issued for its use (e.g., audience- restricting the access token).

OIDC ID Tokens##

OIDC has ID Tokens in addition to Access tokens. The OIDC spec is explicit on the use of the aud claim in ID Tokens. (openid-connect-core-1.0)

aud
REQUIRED. Audience(s) that this ID Token is intended for. It MUST contain the OAuth 2.0 client_id of the Relying Party as an audience value. It MAY also contain identifiers for other audiences. In the general case, the aud value is an array of case sensitive strings. In the common special case when there is one audience, the aud value MAY be a single case sensitive string.

furthermore OIDC specifies the azp claim that is used in conjunction with aud when aud has more than one value.

azp
OPTIONAL. Authorized party - the party to which the ID Token was issued. If present, it MUST contain the OAuth 2.0 Client ID of this party. This Claim is only needed when the ID Token has a single audience value and that audience is different than the authorized party. It MAY be included even when the authorized party is the same as the sole audience. The azp value is a case sensitive string containing a StringOrURI value.

How to extend available properties of User.Identity

Dhaust gives a good way to add the property to the ApplicationUser class. Looking at the OP code it appears they may have done this or were on track to do that. The question asks

How can I retrieve the OrganizationId property of the currently logged in user from within a controller? However, OrganizationId is not a property available in User.Identity. Do I need to extend User.Identity to include the OrganizationId property?

Pawel gives a way to add an extension method that requires using statements or adding the namespace to the web.config file.

However, the question asks if you "need to" extend User.Identity to include the new property. There is an alternative way to access the property without extending User.Identity. If you followed Dhaust method you can then use the following code in your controller to access the new property.

ApplicationDbContext db = new ApplicationDbContext();
var manager = new UserManager<ApplicationUser>(new UserStore<ApplicationUser>(db));
var currentUser = manager.FindById(User.Identity.GetUserId());
var myNewProperty = currentUser.OrganizationId;

Using Excel VBA to run SQL query

Below is code that I currently use to pull data from a MS SQL Server 2008 into VBA. You need to make sure you have the proper ADODB reference [VBA Editor->Tools->References] and make sure you have Microsoft ActiveX Data Objects 2.8 Library checked, which is the second from the bottom row that is checked (I'm using Excel 2010 on Windows 7; you might have a slightly different ActiveX version, but it will still begin with Microsoft ActiveX):

References required for SQL

Sub Module for Connecting to MS SQL with Remote Host & Username/Password

Sub Download_Standard_BOM()
'Initializes variables
Dim cnn As New ADODB.Connection
Dim rst As New ADODB.Recordset
Dim ConnectionString As String
Dim StrQuery As String

'Setup the connection string for accessing MS SQL database
   'Make sure to change:
       '1: PASSWORD
       '2: USERNAME
       '3: REMOTE_IP_ADDRESS
       '4: DATABASE
    ConnectionString = "Provider=SQLOLEDB.1;Password=PASSWORD;Persist Security Info=True;User ID=USERNAME;Data Source=REMOTE_IP_ADDRESS;Use Procedure for Prepare=1;Auto Translate=True;Packet Size=4096;Use Encryption for Data=False;Tag with column collation when possible=False;Initial Catalog=DATABASE"

    'Opens connection to the database
    cnn.Open ConnectionString
    'Timeout error in seconds for executing the entire query; this will run for 15 minutes before VBA timesout, but your database might timeout before this value
    cnn.CommandTimeout = 900

    'This is your actual MS SQL query that you need to run; you should check this query first using a more robust SQL editor (such as HeidiSQL) to ensure your query is valid
    StrQuery = "SELECT TOP 10 * FROM tbl_table"

    'Performs the actual query
    rst.Open StrQuery, cnn
    'Dumps all the results from the StrQuery into cell A2 of the first sheet in the active workbook
    Sheets(1).Range("A2").CopyFromRecordset rst
End Sub

How to decode a QR-code image in (preferably pure) Python?

The following code works fine with me:

brew install zbar
pip install pyqrcode
pip install pyzbar

For QR code image creation:

import pyqrcode
qr = pyqrcode.create("test1")
qr.png("test1.png", scale=6)

For QR code decoding:

from PIL import Image
from pyzbar.pyzbar import decode
data = decode(Image.open('test1.png'))
print(data)

that prints the result:

[Decoded(data=b'test1', type='QRCODE', rect=Rect(left=24, top=24, width=126, height=126), polygon=[Point(x=24, y=24), Point(x=24, y=150), Point(x=150, y=150), Point(x=150, y=24)])]

React.js inline style best practices

The style attribute in React expect the value to be an object, ie Key value pair.

style = {} will have another object inside it like {float:'right'} to make it work.

<span style={{float:'right'}}>{'Download Audit'}</span>

Hope this solves the problem

Converting dictionary to JSON

json.dumps() is used to decode JSON data

  • json.loads take a string as input and returns a dictionary as output.
  • json.dumps take a dictionary as input and returns a string as output.
import json

# initialize different data
str_data = 'normal string'
int_data = 1
float_data = 1.50
list_data = [str_data, int_data, float_data]
nested_list = [int_data, float_data, list_data]
dictionary = {
    'int': int_data,
    'str': str_data,
    'float': float_data,
    'list': list_data,
    'nested list': nested_list
}

# convert them to JSON data and then print it
print('String :', json.dumps(str_data))
print('Integer :', json.dumps(int_data))
print('Float :', json.dumps(float_data))
print('List :', json.dumps(list_data))
print('Nested List :', json.dumps(nested_list, indent=4))
print('Dictionary :', json.dumps(dictionary, indent=4))  # the json data will be indented

output:

String : "normal string"
Integer : 1
Float : 1.5
List : ["normal string", 1, 1.5]
Nested List : [
    1,
    1.5,
    [
        "normal string",
        1,
        1.5
    ]
]
Dictionary : {
    "int": 1,
    "str": "normal string",
    "float": 1.5,
    "list": [
        "normal string",
        1,
        1.5
    ],
    "nested list": [
        1,
        1.5,
        [
            "normal string",
            1,
            1.5
        ]
    ]
}
  • Python Object to JSON Data Conversion
|                 Python                 |  JSON  |
|:--------------------------------------:|:------:|
|                  dict                  | object |
|               list, tuple              |  array |
|                   str                  | string |
| int, float, int- & float-derived Enums | number |
|                  True                  |  true  |
|                  False                 |  false |
|                  None                  |  null  |

The client and server cannot communicate, because they do not possess a common algorithm - ASP.NET C# IIS TLS 1.0 / 1.1 / 1.2 - Win32Exception

After messing with this for days, my final fix for our issues required two things;

1) We added this line of code to all of our .Net libraries that make out bound api calls to other vendors that had also disabled their SSL v3.

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls; // (.Net 4 and below)

2) This is the final and FULL registry changes you will need when you are running ASP.Net 4.0 sites and will need to be slightly changed after you upgrade to ASP.Net 4.5.

After we rebooted the servers - all problems went away after this.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Client]
"DisabledByDefault"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Client]
"Enabled"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Server]
"DisabledByDefault"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 2.0\Server]
"Enabled"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Client]
"DisabledByDefault"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Client]
"Enabled"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server]
"DisabledByDefault"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server]
"Enabled"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Client]
"Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Client]
"DisabledByDefault"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Server]
"Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\Server]
"DisabledByDefault"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Client]
"Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Client]
"DisabledByDefault"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server]
"Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\Server]
"DisabledByDefault"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client]
"Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client]
"DisabledByDefault"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server]
"Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server]
"DisabledByDefault"=dword:00000000

There is already an object named in the database

it seems there is a problem in migration process, run add-migration command in "Package Manager Console":

Add-Migration Initial -IgnoreChanges

do some changes, and then update database from "Initial" file:

Update-Database -verbose

Edit: -IgnoreChanges is in EF6 but not in EF Core, here's a workaround: https://stackoverflow.com/a/43687656/495455

iPhone 6 Plus resolution confusion: Xcode or Apple's website? for development

The answer is that older apps run in 2208 x 1242 Zoomed Mode. But when an app is built for the new phones the resolutions available are: Super Retina HD 5.8 (iPhone X) 1125 x 2436 (458ppi), Retina HD 5.5 (iPhone 6, 7, 8 Plus) 1242 x 2208 and Retina HD 4.7 (iPhone 6) 750 x 1334. This is causing the confusion mentioned in the question. To build apps that use the full screen size of the new phones add LaunchImages in the sizes: 1125 x 2436, 1242 x 2208, 2208 x 1242 and 750 x 1334.


Updated for the new iPhones 12, 12 mini, 12 Pro, 12 Pro Max

Size for iPhone 12 Pro Max with @3x scaling, coordinate space: 428 x 926 points and 1284 x 2778 pixels, 458 ppi, device physical size is 3.07 x 6.33 in or 78.1 x 160.8 mm. 6.7" Super Retina XDR display.

Size for iPhone 12 Pro with @3x scaling, coordinate space: 390 x 844 points and 1170 x 2532 pixels, 460 ppi, device physical size is 2.82 x 5.78 in or 71.5 x 146.7 mm. 6.1" Super Retina XDR display.

Size for iPhone 12 with @2x scaling, coordinate space: 585 x 1266 points and 1170 x 2532 pixels, 460 ppi, device physical size is 2.82 x 5.78 in or 71.5 x 146.7 mm. 6.1" Super Retina XDR display.

Size for iPhone 12 mini with @2x scaling, coordinate space: 540 x 1170 points and 1080 x 2340 pixels, 476 ppi, device physical size is 2.53 x 5.18 in or 64.2 x 131.5 mm. 5.4" Super Retina XDR display.


Size for iPhone 11 Pro Max with @3x scaling, coordinate space: 414 x 896 points and 1242 x 2688 pixels, 458 ppi, device physical size is 3.06 x 6.22 in or 77.8 x 158.0 mm. 6.5" Super Retina XDR display.

Size for iPhone 11 Pro with @3x scaling, coordinate space: 375 x 812 points and 1125 x 2436 pixels, 458 ppi, device physical size is 2.81 x 5.67 in or 71.4 x 144.0 mm. 5.8" Super Retina XDR display.

Size for iPhone 11 with @2x scaling, coordinate space: 414 x 896 points and 828 x 1792 pixels, 326 ppi, device physical size is 2.98 x 5.94 in or 75.7 x 150.9 mm. 6.1" Liquid Retina HD display.

Size for iPhone X Max with @3x scaling (Apple name: Super Retina HD 6.5 display"), coordinate space: 414 x 896 points and 1242 x 2688 pixels, 458 ppi, device physical size is 3.05 x 6.20 in or 77.4 x 157.5 mm.

let screen = UIScreen.main
print("Screen bounds: \(screen.bounds), Screen resolution: \(screen.nativeBounds), scale: \(screen.scale)")
//iPhone X Max Screen bounds: (0.0, 0.0, 414.0, 896.0), Screen resolution: (0.0, 0.0, 1242.0, 2688.0), scale: 3.0

Size for iPhone X with @2x scaling (Apple name: Super Retina HD 6.1" display), coordinate space: 414 x 896 points and 828 x 1792 pixels, 326 ppi, device physical size is 2.98 x 5.94 in or 75.7 x 150.9 mm.

let screen = UIScreen.main
print("Screen bounds: \(screen.bounds), Screen resolution: \(screen.nativeBounds), scale: \(screen.scale)")
//iPhone X Screen bounds: (0.0, 0.0, 414.0, 896.0), Screen resolution: (0.0, 0.0, 828.0, 1792.0), scale: 2.0

Size for iPhone X and iPhone X with @3x scaling (Apple name: Super Retina HD 5.8" display), coordinate space: 375 x 812 points and 1125 x 2436 pixels, 458 ppi, device physical size is 2.79 x 5.65 in or 70.9 x 143.6 mm.

let screen = UIScreen.main
print("Screen bounds: \(screen.bounds), Screen resolution: \(screen.nativeBounds), scale: \(screen.scale)")
//iPhone X and X Screen bounds: (0.0, 0.0, 375.0, 812.0), Screen resolution: (0.0, 0.0, 1125.0, 2436.0), scale: 3.0

enter image description here

Size for iPhone 6, 6S, 7 and 8 with @3x scaling (Apple name: Retina HD 5.5), coordinate space: 414 x 736 points and 1242 x 2208 pixels, 401 ppi, screen physical size is 2.7 x 4.8 in or 68 x 122 mm. When running in Zoomed Mode, i.e. without the new LaunchImages or choosen in Setup on iPhone 6 Plus, the native scale is 2.88 and the screen is 320 x 568 points, which is the iPhone 5 native size:

Screen bounds: {{0, 0}, {414, 736}}, Screen resolution: <UIScreen: 0x7f97fad330b0; bounds = {{0, 0}, {414, 736}};
mode = <UIScreenMode: 0x7f97fae1ce00; size = 1242.000000 x 2208.000000>>, scale: 3.000000, nativeScale: 3.000000

Size for iPhone 6 and iPhone 6S with @2x scaling (Apple name: Retina HD 4.7), coordinate space: 375 x 667 points and 750 x 1334 pixels, 326 ppi, screen physical size is 2.3 x 4.1 in or 58 x 104 mm. When running in Zoomed Mode, i.e. without the new LaunchImages, the screen is 320 x 568 points, which is the iPhone 5 native size:

Screen bounds: {{0, 0}, {375, 667}}, Screen resolution: <UIScreen: 0x7fa01b5182d0; bounds = {{0, 0}, {375, 667}};
mode = <UIScreenMode: 0x7fa01b711760; size = 750.000000 x 1334.000000>>, scale: 2.000000, nativeScale: 2.000000

And iPhone 5 for comparison is 640 x 1136, iPhone 4 640 x 960.


Here is the code I used to check this out (note that nativeScale only runs on iOS 8):

UIScreen *mainScreen = [UIScreen mainScreen];
NSLog(@"Screen bounds: %@, Screen resolution: %@, scale: %f, nativeScale: %f",
          NSStringFromCGRect(mainScreen.bounds), mainScreen.coordinateSpace, mainScreen.scale, mainScreen.nativeScale);

Note: Upload LaunchImages otherwise the app will run in Zoomed Mode and not show the correct scaling, or screen sizes. In Zoomed Mode the nativeScale and scale will not be the same. On an actual device the scale can be 2.608 on the iPhone 6 Plus, even when it is not running in Zoomed Mode, but it will show scale of 3.0 when running on the simulator.

Comparing iPhone 6 and 6 Plus

Httpd returning 503 Service Unavailable with mod_proxy for Tomcat 8

On CentOS Linux release 7.5.1804, we were able to make this work by editing /etc/selinux/config and changing the setting of SELINUX like so:

SELINUX=disabled

Windows.history.back() + location.reload() jquery

You can't do window.history.back(); and location.reload(); in the same function.

window.history.back() breaks the javascript flow and redirects to previous page, location.reload() is never processed.

location.reload() has to be called on the page you redirect to when using window.history.back().

I would used an url to redirect instead of history.back, that gives you both a redirect and refresh.

How to update a claim in ASP.NET Identity?

To remove claim details from database we can use below code. Also, we need to sign in again to update the cookie values

 // create a new identity 
            var identity = new ClaimsIdentity(User.Identity);

            // Remove the existing claim value of current user from database
            if(identity.FindFirst("NameOfUser")!=null)
                await UserManager.RemoveClaimAsync(applicationUser.Id, identity.FindFirst("NameOfUser"));

            // Update customized claim 
            await UserManager.AddClaimAsync(applicationUser.Id, new Claim("NameOfUser", applicationUser.Name));

            // the claim has been updates, We need to change the cookie value for getting the updated claim
            AuthenticationManager.SignOut(identity.AuthenticationType);
            await SignInManager.SignInAsync(Userprofile, isPersistent: false, rememberBrowser: false);

            return RedirectToAction("Index", "Home");

Swift how to sort array of custom objects by property value

Swift 4.0, 4.1 & 4.2 First, I created mutable array of type imageFile() as shown below

var arr = [imageFile]()

Create mutable object image of type imageFile() and assign value to properties as shown below

   var image = imageFile()
   image.fileId = 14
   image.fileName = "A"

Now, append this object to array arr

    arr.append(image)

Now, assign the different properties to same mutable object i.e image

   image = imageFile()
   image.fileId = 13
   image.fileName = "B"

Now, again append image object to array arr

    arr.append(image)

Now, we will apply Ascending order on fileId property in array arr objects. Use < symbol for Ascending order

 arr = arr.sorted(by: {$0.fileId < $1.fileId}) // arr has all objects in Ascending order
 print("sorted array is",arr[0].fileId)// sorted array is 13
 print("sorted array is",arr[1].fileId)//sorted array is 14

Now, we will apply Descending order on on fileId property in array arr objects. Use > symbol for Descending order

 arr = arr.sorted(by: {$0.fileId > $1.fileId}) // arr has all objects in Descending order
 print("Unsorted array is",arr[0].fileId)// Unsorted array is 14
 print("Unsorted array is",arr[1].fileId)// Unsorted array is 13

In Swift 4.1. & 4.2 For sorted order use

let sortedArr = arr.sorted { (id1, id2) -> Bool in
  return id1.fileId < id2.fileId // Use > for Descending order
}

Read and write a String from text file

I had to recode like this:

let path = NSBundle.mainBundle().pathForResource("Output_5", ofType: "xml")
let text = try? NSString(contentsOfFile: path! as String, encoding: NSUTF8StringEncoding)
print(text)

HTML 5 Favicon - Support?

No, not all browsers support the sizes attribute:

Note that some platforms define specific sizes:

Unfortunately MyApp has stopped. How can I solve this?

Let me share a basic Logcat analysis for when you meet a Force Close (when the app stops working).

DOCS

The basic tool from Android to collect/analyze logs is the logcat.

HERE is the Android's page about logcat

If you use android Studio, you can also check this LINK.

Capturing

Basically, you can MANUALLY capture logcat with the following command (or just check AndroidMonitor window in AndroidStudio):

adb logcat

There's a lot of parameters you can add to the command which helps you to filter and display the message that you want... This is personal... I always use the command below to get the message timestamp:

adb logcat -v time

You can redirect the output to a file and analyze it in a Text Editor.

Analyzing

If you app is Crashing, you'll get something like:

07-09 08:29:13.474 21144-21144/com.example.khan.abc D/AndroidRuntime: Shutting down VM
07-09 08:29:13.475 21144-21144/com.example.khan.abc E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.khan.abc, PID: 21144
    java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v4.app.FragmentActivity.onBackPressed()' on a null object reference
     at com.example.khan.abc.AudioFragment$1.onClick(AudioFragment.java:125)
     at android.view.View.performClick(View.java:4848)
     at android.view.View$PerformClick.run(View.java:20262)
     at android.os.Handler.handleCallback(Handler.java:815)
     at android.os.Handler.dispatchMessage(Handler.java:104)
     at android.os.Looper.loop(Looper.java:194)
     at android.app.ActivityThread.main(ActivityThread.java:5631)
     at java.lang.reflect.Method.invoke(Native Method)
     at java.lang.reflect.Method.invoke(Method.java:372)
     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:959)
     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)
07-09 08:29:15.195 21144-21144/com.example.khan.abc I/Process: Sending signal. PID: 21144 SIG: 9

This part of the log shows you a lot of information:

  • When the issue happened: 07-09 08:29:13.475

It is important to check when the issue happened... You may find several errors in a log... you must be sure that you are checking the proper messages :)

  • Which app crashed: com.example.khan.abc

This way, you know which app crashed (to be sure that you are checking the logs about your message)

  • Which ERROR: java.lang.NullPointerException

A NULL Pointer Exception error

  • Detailed info about the error: Attempt to invoke virtual method 'void android.support.v4.app.FragmentActivity.onBackPressed()' on a null object reference

You tried to call method onBackPressed() from a FragmentActivity object. However, that object was null when you did it.

  • Stack Trace: Stack Trace shows you the method invocation order... Sometimes, the error happens in the calling method (and not in the called method).

    at com.example.khan.abc.AudioFragment$1.onClick(AudioFragment.java:125)

Error happened in file com.example.khan.abc.AudioFragment.java, inside onClick() method at line: 125 (stacktrace shows the line that error happened)

It was called by:

at android.view.View.performClick(View.java:4848)

Which was called by:

at android.view.View$PerformClick.run(View.java:20262)

which was called by:

at android.os.Handler.handleCallback(Handler.java:815)

etc....

Overview

This was just an overview... Not all logs are simple but the error gives specific problem and verbose shows up all problem ... It is just to share the idea and provide entry-level information to you...

I hope I could help you someway... Regards

The model backing the 'ApplicationDbContext' context has changed since the database was created

If you delete the "[__MigrationHistory]" table from your "database > System Tables" then it will work.

Named colors in matplotlib

In addition to BoshWash's answer, here is the picture generated by his code:

Named colors

How can I open a .tex file?

I don't know what the .tex extension on your file means. If we are saying that it is any file with any extension you have several methods of reading it.

I have to assume you are using windows because you have mentioned notepad++.

  1. Use notepad++. Right click on the file and choose "edit with notepad++"

  2. Use notepad Change the filename extension to .txt and double click the file.

  3. Use command prompt. Open the folder that your file is in. Hold down shift and right click. (not on the file, but in the folder that the file is in.) Choose "open command window here" from the command prompt type: "type filename.tex"

If these don't work, I would need more detail as to how they are not working. Errors that you may be getting or what you may expect to be in the file might help.

What is the `data-target` attribute in Bootstrap 3?

The toggle tells Bootstrap what to do and the target tells Bootstrap which element is going to open. So whenever a link like that is clicked, a modal with an id of “basicModal” will appear.

Detecting iOS / Android Operating system

You can test the user agent string:

/**
 * Determine the mobile operating system.
 * This function returns one of 'iOS', 'Android', 'Windows Phone', or 'unknown'.
 *
 * @returns {String}
 */
function getMobileOperatingSystem() {
  var userAgent = navigator.userAgent || navigator.vendor || window.opera;

      // Windows Phone must come first because its UA also contains "Android"
    if (/windows phone/i.test(userAgent)) {
        return "Windows Phone";
    }

    if (/android/i.test(userAgent)) {
        return "Android";
    }

    // iOS detection from: http://stackoverflow.com/a/9039885/177710
    if (/iPad|iPhone|iPod/.test(userAgent) && !window.MSStream) {
        return "iOS";
    }

    return "unknown";
}

How does Facebook disable the browser's integrated Developer Tools?

This is not a security measure for weak code to be left unattended. Always get a permanent solution to weak code and secure your websites properly before implementing this strategy

The best tool by far according to my knowledge would be to add multiple javascript files that simply changes the integrity of the page back to normal by refreshing or replacing content. Disabling this developer tool would not be the greatest idea since bypassing is always in question since the code is part of the browser and not a server rendering, thus it could be cracked.

Should you have js file one checking for <element> changes on important elements and js file two and js file three checking that this file exists per period you will have full integrity restore on the page within the period.

Lets take an example of the 4 files and show you what I mean.

index.html

   <!DOCTYPE html>
   <html>
   <head id="mainhead">
   <script src="ks.js" id="ksjs"></script>
   <script src="mainfile.js" id="mainjs"></script>
   <link rel="stylesheet" href="style.css" id="style">
   <meta id="meta1" name="description" content="Proper mitigation against script kiddies via Javascript" >
   </head>
   <body>
   <h1 id="heading" name="dontdel" value="2">Delete this from console and it will refresh. If you change the name attribute in this it will also refresh. This is mitigating an attack on attribute change via console to exploit vulnerabilities. You can even try and change the value attribute from 2 to anything you like. If This script says it is 2 it should be 2 or it will refresh. </h1>
   <h3>Deleting this wont refresh the page due to it having no integrity check on it</h3>

   <p>You can also add this type of error checking on meta tags and add one script out of the head tag to check for changes in the head tag. You can add many js files to ensure an attacker cannot delete all in the second it takes to refresh. Be creative and make this your own as your website needs it. 
   </p>

   <p>This is not the end of it since we can still enter any tag to load anything from everywhere (Dependent on headers etc) but we want to prevent the important ones like an override in meta tags that load headers. The console is designed to edit html but that could add potential html that is dangerous. You should not be able to enter any meta tags into this document unless it is as specified by the ks.js file as permissable. <br>This is not only possible with meta tags but you can do this for important tags like input and script. This is not a replacement for headers!!! Add your headers aswell and protect them with this method.</p>
   </body>
   <script src="ps.js" id="psjs"></script>
   </html>

mainfile.js

   setInterval(function() {
   // check for existence of other scripts. This part will go in all other files to check for this file aswell. 
   var ksExists = document.getElementById("ksjs"); 
   if(ksExists) {
   }else{ location.reload();};

   var psExists = document.getElementById("psjs");
   if(psExists) {
   }else{ location.reload();};

   var styleExists = document.getElementById("style");
   if(styleExists) {
   }else{ location.reload();};


   }, 1 * 1000); // 1 * 1000 milsec

ps.js

   /*This script checks if mainjs exists as an element. If main js is not existent as an id in the html file reload!You can add this to all js files to ensure that your page integrity is perfect every second. If the page integrity is bad it reloads the page automatically and the process is restarted. This will blind an attacker as he has one second to disable every javascript file in your system which is impossible.

   */

   setInterval(function() {
   // check for existence of other scripts. This part will go in all other files to check for this file aswell. 
   var mainExists = document.getElementById("mainjs"); 
   if(mainExists) {
   }else{ location.reload();};

   //check that heading with id exists and name tag is dontdel.
   var headingExists = document.getElementById("heading"); 
   if(headingExists) {
   }else{ location.reload();};
   var integrityHeading = headingExists.getAttribute('name');
   if(integrityHeading == 'dontdel') {
   }else{ location.reload();};
   var integrity2Heading = headingExists.getAttribute('value');
   if(integrity2Heading == '2') {
   }else{ location.reload();};
   //check that all meta tags stay there
   var meta1Exists = document.getElementById("meta1"); 
   if(meta1Exists) {
   }else{ location.reload();};

   var headExists = document.getElementById("mainhead"); 
   if(headExists) {
   }else{ location.reload();};

   }, 1 * 1000); // 1 * 1000 milsec

ks.js

   /*This script checks if mainjs exists as an element. If main js is not existent as an id in the html file reload! You can add this to all js files to ensure that your page integrity is perfect every second. If the page integrity is bad it reloads the page automatically and the process is restarted. This will blind an attacker as he has one second to disable every javascript file in your system which is impossible.

   */

   setInterval(function() {
   // check for existence of other scripts. This part will go in all other files to check for this file aswell. 
   var mainExists = document.getElementById("mainjs"); 
   if(mainExists) {
   }else{ location.reload();};
   //Check meta tag 1 for content changes. meta1 will always be 0. This you do for each meta on the page to ensure content credibility. No one will change a meta and get away with it. Addition of a meta in spot 10, say a meta after the id="meta10" should also be covered as below.
   var x = document.getElementsByTagName("meta")[0];
   var p = x.getAttribute("name");
   var s = x.getAttribute("content");
   if (p != 'description') {
   location.reload();
   }
   if ( s != 'Proper mitigation against script kiddies via Javascript') {
   location.reload();
   }
   // This will prevent a meta tag after this meta tag @ id="meta1". This prevents new meta tags from being added to your pages. This can be used for scripts or any tag you feel is needed to do integrity check on like inputs and scripts. (Yet again. It is not a replacement for headers to be added. Add your headers aswell!)
   var lastMeta = document.getElementsByTagName("meta")[1];
   if (lastMeta) {
   location.reload();
   }
   }, 1 * 1000); // 1 * 1000 milsec

style.css

Now this is just to show it works on all files and tags aswell

   #heading {
   background-color:red;
   }

If you put all these files together and build the example you will see the function of this measure. This will prevent some unforseen injections should you implement it correctly on all important elements in your index file especially when working with PHP.

Why I chose reload instead of change back to normal value per attribute is the fact that some attackers could have another part of the website already configured and ready and it lessens code amount. The reload will remove all the attacker's hard work and he will probably go play somewhere easier.

Another note: This could become a lot of code so keep it clean and make sure to add definitions to where they belong to make edits easy in future. Also set the seconds to your preferred amount as 1 second intervals on large pages could have drastic effects on older computers your visitors might be using

org.hibernate.QueryException: could not resolve property: filename

Hibernate queries are case sensitive with property names (because they end up relying on getter/setter methods on the @Entity).

Make sure you refer to the property as fileName in the Criteria query, not filename.

Specifically, Hibernate will call the getter method of the filename property when executing that Criteria query, so it will look for a method called getFilename(). But the property is called FileName and the getter getFileName().

So, change the projection like so:

criteria.setProjection(Projections.property("fileName"));

MVC 5 Access Claims Identity User Data

Request.GetOwinContext().Authentication.User.Claims

However it is better to add the claims inside the "GenerateUserIdentityAsync" method, especially if regenerateIdentity in the Startup.Auth.cs is enabled.

How do I install Composer on a shared hosting?

I was able to install composer on HostGator's shared hosting. Logged in to SSH with Putty, right after login you should be in your home directory, which is usually /home/username, where username is your username obviously. Then ran the curl command posted by @niutech above. This downloaded the composer to my home directory and it's now accessible and working well.

In Java, can you modify a List while iterating through it?

There is nothing wrong with the idea of modifying an element inside a list while traversing it (don't modify the list itself, that's not recommended), but it can be better expressed like this:

for (int i = 0; i < letters.size(); i++) {
    letters.set(i, "D");
}

At the end the whole list will have the letter "D" as its content. It's not a good idea to use an enhanced for loop in this case, you're not using the iteration variable for anything, and besides you can't modify the list's contents using the iteration variable.

Notice that the above snippet is not modifying the list's structure - meaning: no elements are added or removed and the lists' size remains constant. Simply replacing one element by another doesn't count as a structural modification. Here's the link to the documentation quoted by @ZouZou in the comments, it states that:

A structural modification is any operation that adds or deletes one or more elements, or explicitly resizes the backing array; merely setting the value of an element is not a structural modification

Run-time error '1004' - Method 'Range' of object'_Global' failed

When you reference Range like that it's called an unqualified reference because you don't specifically say which sheet the range is on. Unqualified references are handled by the "_Global" object that determines which object you're referring to and that depends on where your code is.

If you're in a standard module, unqualified Range will refer to Activesheet. If you're in a sheet's class module, unqualified Range will refer to that sheet.

inputTemplateContent is a variable that contains a reference to a range, probably a named range. If you look at the RefersTo property of that named range, it likely points to a sheet other than the Activesheet at the time the code executes.

The best way to fix this is to avoid unqualified Range references by specifying the sheet. Like

With ThisWorkbook.Worksheets("Template")
    .Range(inputTemplateHeader).Value = NO_ENTRY
    .Range(inputTemplateContent).Value = NO_ENTRY
End With

Adjust the workbook and worksheet references to fit your particular situation.

Uncaught TypeError: Cannot read property 'length' of undefined

console.log(typeof json_data !== 'undefined'
    ? json_data.length : 'There is no spoon.');

...or more simply...

console.log(json_data ? json_data.length : 'json_data is null or undefined');

Download JSON object as a file from browser

This is how I solved it for my application:

HTML: <a id="downloadAnchorElem" style="display:none"></a>

JS (pure JS, not jQuery here):

var dataStr = "data:text/json;charset=utf-8," + encodeURIComponent(JSON.stringify(storageObj));
var dlAnchorElem = document.getElementById('downloadAnchorElem');
dlAnchorElem.setAttribute("href",     dataStr     );
dlAnchorElem.setAttribute("download", "scene.json");
dlAnchorElem.click();

In this case, storageObj is the js object you want to store, and "scene.json" is just an example name for the resulting file.

This approach has the following advantages over other proposed ones:

  • No HTML element needs to be clicked
  • Result will be named as you want it
  • no jQuery needed

I needed this behavior without explicit clicking since I want to trigger the download automatically at some point from js.

JS solution (no HTML required):

  function downloadObjectAsJson(exportObj, exportName){
    var dataStr = "data:text/json;charset=utf-8," + encodeURIComponent(JSON.stringify(exportObj));
    var downloadAnchorNode = document.createElement('a');
    downloadAnchorNode.setAttribute("href",     dataStr);
    downloadAnchorNode.setAttribute("download", exportName + ".json");
    document.body.appendChild(downloadAnchorNode); // required for firefox
    downloadAnchorNode.click();
    downloadAnchorNode.remove();
  }

Select multiple columns using Entity Framework

You either want to select an anonymous type:

var dataset2 = from recordset 
               in entities.processlists 
               where recordset.ProcessName == processname 
               select new 
               {
                recordset.ServerName, 
                recordset.ProcessID, 
                recordset.Username
               };

But you cannot cast that to another type, so I guess you want something like this:

var dataset2 = from recordset 
               in entities.processlists 
               where recordset.ProcessName == processname 

               // Select new concrete type
               select new PInfo
               {
                ServerName = recordset.ServerName, 
                ProcessID = recordset.ProcessID, 
                Username = recordset.Username
               };

How to check if an email address is real or valid using PHP

You can't verify (with enough accuracy to rely on) if an email actually exists using just a single PHP method. You can send an email to that account, but even that alone won't verify the account exists (see below). You can, at least, verify it's at least formatted like one

if(filter_var($email, FILTER_VALIDATE_EMAIL)) {
    //Email is valid
}

You can add another check if you want. Parse the domain out and then run checkdnsrr

if(checkdnsrr($domain)) {
     // Domain at least has an MX record, necessary to receive email
}

Many people get to this point and are still unconvinced there's not some hidden method out there. Here are some notes for you to consider if you're bound and determined to validate email:

  1. Spammers also know the "connection trick" (where you start to send an email and rely on the server to bounce back at that point). One of the other answers links to this library which has this caveat

    Some mail servers will silently reject the test message, to prevent spammers from checking against their users' emails and filter the valid emails, so this function might not work properly with all mail servers.

    In other words, if there's an invalid address you might not get an invalid address response. In fact, virtually all mail servers come with an option to accept all incoming mail (here's how to do it with Postfix). The answer linking to the validation library neglects to mention that caveat.

  2. Spam blacklists. They blacklist by IP address and if your server is constantly doing verification connections you run the risk of winding up on Spamhaus or another block list. If you get blacklisted, what good does it do you to validate the email address?

  3. If it's really that important to verify an email address, the accepted way is to force the user to respond to an email. Send them a full email with a link they have to click to be verified. It's not spammy, and you're guaranteed that any responses have a valid address.

How to reference a local XML Schema file correctly?

Add one more slash after file:// in the value of xsi:schemaLocation. (You have two; you need three. Think protocol://host/path where protocol is 'file' and host is empty here, yielding three slashes in a row.) You can also eliminate the double slashes along the path. I believe that the double slashes help with file systems that allow spaces in file and directory names, but you wisely avoided that complication in your path naming.

xsi:schemaLocation="http://www.w3schools.com file:///C:/environment/workspace/maven-ws/ProjextXmlSchema/email.xsd"

Still not working? I suggest that you carefully copy the full file specification for the XSD into the address bar of Chrome or Firefox:

file:///C:/environment/workspace/maven-ws/ProjextXmlSchema/email.xsd

If the XSD does not display in the browser, delete all but the last component of the path (email.xsd) and see if you can't display the parent directory. Continue in this manner, walking up the directory structure until you discover where the path diverges from the reality of your local filesystem.

If the XSD does displayed in the browser, state what XML processor you're using, and be prepared to hear that it's broken or that you must work around some limitation. I can tell you that the above fix will work with my Xerces-J-based validator.

Best practice multi language website

A really simple option that works with any website where you can upload Javascript is www.multilingualizer.com

It lets you put all text for all languages onto one page and then hides the languages the user doesn't need to see. Works well.

TypeError: Cannot read property "0" from undefined

The while increments the i. So you get:

data[1][0]
data[2][0]
data[3][0]
...

It looks like name doesn't match any of the the elements of data. So, the while still increments and you reach the end of the array. I'll suggest to use for loop.

Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?

Because pypy is not 100% compatible, takes 8 gigs of ram to compile, is a moving target, and highly experimental, where cpython is stable, the default target for module builders for 2 decades (including c extensions that don't work on pypy), and already widely deployed.

Pypy will likely never be the reference implementation, but it is a good tool to have.

Detecting IE11 using CSS Capability/Feature Detection

I ran into the same problem with a Gravity Form (WordPress) in IE11. The form's column style "display: inline-grid" broke the layout; applying the answers above resolved the discrepancy!

@media all and (-ms-high-contrast:none){
  *::-ms-backdrop, .gfmc-column { display: inline-block;} /* IE11 */
}

Wait for async task to finish

How about calling a function from within your callback instead of returning a value in sync_call()?

function sync_call(input) {
    var value;

    // Assume the async call always succeed
    async_call(input, function(result) {
        value = result;
        use_value(value);
    } );
}

stale element reference: element is not attached to the page document

Whenever you face this issue, just define the web element once again above the line in which you are getting an Error.

Example:

WebElement button = driver.findElement(By.xpath("xpath"));
button.click();

//here you do something like update or save 

//then you try to use the button WebElement again to click 
button.click();

Since the DOM has changed e.g. through the update action, you are receiving a StaleElementReference Error.

Solution:

WebElement button = driver.findElement(By.xpath("xpath"));
button.click();

//here you do something like update or save 

//then you define the button element again before you use it
WebElement button1 = driver.findElement(By.xpath("xpath"));
//that new element will point to the same element in the new DOM
button1.click();

PostgreSQL - query from bash script as database user 'postgres'

To ans to @Jason 's question, in my bash script, I've dome something like this (for my purpose):

dbPass='xxxxxxxx'
.....
## Connect to the DB
PGPASSWORD=${dbPass} psql -h ${dbHost} -U ${myUsr} -d ${myRdb} -P pager=on --set AUTOCOMMIT=off

The another way of doing it is:

psql --set AUTOCOMMIT=off --set ON_ERROR_STOP=on -P pager=on \
     postgresql://${myUsr}:${dbPass}@${dbHost}/${myRdb}

but you have to be very careful about the password: I couldn't make a password with a ' and/or a : to work in that way. So gave up in the end.

-S

Grouped bar plot in ggplot

First you need to get the counts for each category, i.e. how many Bads and Goods and so on are there for each group (Food, Music, People). This would be done like so:

raw <- read.csv("http://pastebin.com/raw.php?i=L8cEKcxS",sep=",")
raw[,2]<-factor(raw[,2],levels=c("Very Bad","Bad","Good","Very Good"),ordered=FALSE)
raw[,3]<-factor(raw[,3],levels=c("Very Bad","Bad","Good","Very Good"),ordered=FALSE)
raw[,4]<-factor(raw[,4],levels=c("Very Bad","Bad","Good","Very Good"),ordered=FALSE)

raw=raw[,c(2,3,4)] # getting rid of the "people" variable as I see no use for it

freq=table(col(raw), as.matrix(raw)) # get the counts of each factor level

Then you need to create a data frame out of it, melt it and plot it:

Names=c("Food","Music","People")     # create list of names
data=data.frame(cbind(freq),Names)   # combine them into a data frame
data=data[,c(5,3,1,2,4)]             # sort columns

# melt the data frame for plotting
data.m <- melt(data, id.vars='Names')

# plot everything
ggplot(data.m, aes(Names, value)) +   
  geom_bar(aes(fill = variable), position = "dodge", stat="identity")

Is this what you're after?

enter image description here

To clarify a little bit, in ggplot multiple grouping bar you had a data frame that looked like this:

> head(df)
  ID Type Annee X1PCE X2PCE X3PCE X4PCE X5PCE X6PCE
1  1    A  1980   450   338   154    36    13     9
2  2    A  2000   288   407   212    54    16    23
3  3    A  2020   196   434   246    68    19    36
4  4    B  1980   111   326   441    90    21    11
5  5    B  2000    63   298   443   133    42    21
6  6    B  2020    36   257   462   162    55    30

Since you have numerical values in columns 4-9, which would later be plotted on the y axis, this can be easily transformed with reshape and plotted.

For our current data set, we needed something similar, so we used freq=table(col(raw), as.matrix(raw)) to get this:

> data
   Names Very.Bad Bad Good Very.Good
1   Food        7   6    5         2
2  Music        5   5    7         3
3 People        6   3    7         4

Just imagine you have Very.Bad, Bad, Good and so on instead of X1PCE, X2PCE, X3PCE. See the similarity? But we needed to create such structure first. Hence the freq=table(col(raw), as.matrix(raw)).

Which JDK version (Language Level) is required for Android Studio?

Android Studio now comes bundled with OpenJDK 8 . Legacy projects can still use JDK7 or JDK8

Reference: https://developer.android.com/studio/releases/index.html

The type List is not generic; it cannot be parameterized with arguments [HTTPClient]

Your import has a subtle error:

import java.awt.List;

It should be:

import java.util.List;

The problem is that both awt and Java's util package provide a class called List. The former is a display element, the latter is a generic type used with collections. Furthermore, java.util.ArrayList extends java.util.List, not java.awt.List so if it wasn't for the generics, it would have still been a problem.

Edit: (to address further questions given by OP) As an answer to your comment, it seems that there is anther subtle import issue.

import org.omg.DynamicAny.NameValuePair;

should be

import org.apache.http.NameValuePair

nameValuePairs now uses the correct generic type parameter, the generic argument for new UrlEncodedFormEntity, which is List<? extends NameValuePair>, becomes valid, since your NameValuePair is now the same as their NameValuePair. Before, org.omg.DynamicAny.NameValuePair did not extend org.apache.http.NameValuePair and the shortened type name NameValuePair evaluated to org.omg... in your file, but org.apache... in their code.

Technically what is the main difference between Oracle JDK and OpenJDK?

Technical differences are a consequence of the goal of each one (OpenJDK is meant to be the reference implementation, open to the community, while Oracle is meant to be a commercial one)

They both have "almost" the same code of the classes in the Java API; but the code for the virtual machine itself is actually different, and when it comes to libraries, OpenJDK tends to use open libraries while Oracle tends to use closed ones; for instance, the font library.

Python readlines() usage and efficient practice for reading

Read line by line, not the whole file:

for line in open(file_name, 'rb'):
    # process line here

Even better use with for automatically closing the file:

with open(file_name, 'rb') as f:
    for line in f:
        # process line here

The above will read the file object using an iterator, one line at a time.

How do you send an HTTP Get Web Request in Python?

In Python, you can use urllib2 (http://docs.python.org/2/library/urllib2.html) to do all of that work for you.

Simply enough:

import urllib2
f =  urllib2.urlopen(url)
print f.read() 

Will print the received HTTP response.

To pass GET/POST parameters the urllib.urlencode() function can be used. For more information, you can refer to the Official Urllib2 Tutorial

Fixed height and width for bootstrap carousel

To have a consistent flow of the images on different devices, you'd have to specify the width and height value for each carousel image item, for instance here in my example the image would take the full width but with a height of "400px" (you can specify your personal value instead)

<div class="item">
        <img src="image.jpg" style="width:100%; height: 400px;">
      </div>

Windows 7, 64 bit, DLL problems

As mentioned, DCOMP is part of the VC++ redistributables (implementing the OpenMP runtime) and is the only truly missing component. All the rest are false reports.

Specifically API-MS-WIN-XXXX.DLL are API-sets - essentially, an extra level of call indirection introduced gradually since Windows 7. Dependency Walker development seemingly halted long before that, and it can't handle API sets properly.

So there is nothing to worry about there. You're not missing anything more.

A better alternative to find the truly needed DLL files that are missing (if that is indeed the problem) is to run Process Monitor and step backwards from the failure, searching for sequences of failed probes for a specific DLL file in all the system path.

Batch file for PuTTY/PSFTP file transfer automation

set DSKTOPDIR="D:\test"
set IPADDRESS="23.23.3.23"

>%DSKTOPDIR%\script.ftp ECHO cd %PAY_REP%
>>%DSKTOPDIR%\script.ftp ECHO mget *.report
>>%DSKTOPDIR%\script.ftp ECHO bye

:: run PSFTP Commands
psftp <domain>@%IPADDRESS% -b %DSKTOPDIR%\script.ftp

Set values using set commands before above lines.

I believe this helps you.

Referre psfpt setup for below link https://www.ssh.com/ssh/putty/putty-manuals/0.68/Chapter6.html

Which websocket library to use with Node.js?

npm ws was the answer for me. I found it less intrusive and more straight forward. With it was also trivial to mix websockets with rest services. Shared simple code on this post.

var WebSocketServer = require("ws").Server;
var http = require("http");
var express = require("express");
var port = process.env.PORT || 5000;

var app = express();
    app.use(express.static(__dirname+ "/../"));
    app.get('/someGetRequest', function(req, res, next) {
       console.log('receiving get request');
    });
    app.post('/somePostRequest', function(req, res, next) {
       console.log('receiving post request');
    });
    app.listen(80); //port 80 need to run as root

    console.log("app listening on %d ", 80);

var server = http.createServer(app);
    server.listen(port);

console.log("http server listening on %d", port);

var userId;
var wss = new WebSocketServer({server: server});
    wss.on("connection", function (ws) {

    console.info("websocket connection open");

    var timestamp = new Date().getTime();
    userId = timestamp;

    ws.send(JSON.stringify({msgType:"onOpenConnection", msg:{connectionId:timestamp}}));


    ws.on("message", function (data, flags) {
        console.log("websocket received a message");
        var clientMsg = data;

        ws.send(JSON.stringify({msg:{connectionId:userId}}));


    });

    ws.on("close", function () {
        console.log("websocket connection close");
    });
});
console.log("websocket server created");

C: scanf to array

The %d conversion specifier will only convert one decimal integer. It doesn't know that you're passing an array, it can't modify its behavior based on that. The conversion specifier specifies the conversion.

There is no specifier for arrays, you have to do it explicitly. Here's an example with four conversions:

if(scanf("%d %d %d %d", &array[0], &array[1], &array[2], &array[3]) == 4)
  printf("got four numbers\n");

Note that this requires whitespace between the input numbers.

If the id is a single 11-digit number, it's best to treat as a string:

char id[12];

if(scanf("%11s", id) == 1)
{
  /* inspect the *character* in id[0], compare with '1' or '2' for instance. */
}

How can I bold the fonts of a specific row or cell in an Excel worksheet with C#?

I have done this in a project a long time ago. The code given below write a whole rows bold with specific column names and all of these columns are written in bold format.

private void WriteColumnHeaders(DataColumnCollection columnCollection, int row, int column)
    {
        // row represent particular row you want to bold its content.
        for (i = 0; i < columnCollection.Count; i++)
        {
            DataColumn col = columnCollection[i];
            xlWorkSheet.Cells[row, column + i + 1] = col.Caption;
            // Some Font Styles
            xlWorkSheet.Cells[row, column + i + 1].Style.Font.Bold = true;
            xlWorkSheet.Cells[row, column + i + 1].Interior.Color = Color.FromArgb(192, 192, 192);
            //xlWorkSheet.Columns[i + 1].ColumnWidth = xlWorkSheet.Columns[i+1].ColumnWidth + 10;
        }
    }

You must pass value of row 0 so that first row of your excel sheets have column headers with bold font size. Just change DataColumnCollection to your columns name and change col.Caption to specific column name.

Alternate

You may do this to cell of excel sheet you want bold.

xlWorkSheet.Cells[row, column].Style.Font.Bold = true;

Run Command Line & Command From VBS

Set oShell = CreateObject ("WScript.Shell") 
oShell.run "cmd.exe /C copy ""S:Claims\Sound.wav"" ""C:\WINDOWS\Media\Sound.wav"" "

ASP.Net MVC: Calling a method from a view

You should create custom helper for just changing string format except using controller call.

UL has margin on the left

by default <UL/> contains default padding

therefore try adding style to padding:0px in css class or inline css

Spring Test & Security: How to mock authentication?

Create a class TestUserDetailsImpl on your test package:

@Service
@Primary
@Profile("test")
public class TestUserDetailsImpl implements UserDetailsService {
    public static final String API_USER = "[email protected]";

    private User getAdminUser() {
        User user = new User();
        user.setUsername(API_USER);

        SimpleGrantedAuthority role = new SimpleGrantedAuthority("ROLE_API_USER");
        user.setAuthorities(Collections.singletonList(role));

        return user;
    }

    @Override
    public UserDetails loadUserByUsername(String username) 
                                         throws UsernameNotFoundException {
        if (Objects.equals(username, ADMIN_USERNAME))
            return getAdminUser();
        throw new UsernameNotFoundException(username);
    }
}

Rest endpoint:

@GetMapping("/invoice")
@Secured("ROLE_API_USER")
public Page<InvoiceDTO> getInvoices(){
   ...
}

Test endpoint:

@Test
@WithUserDetails("[email protected]")
public void testApi() throws Exception {
     ...
}

How using try catch for exception handling is best practice

My exception-handling strategy is:

  • To catch all unhandled exceptions by hooking to the Application.ThreadException event, then decide:

    • For a UI application: to pop it to the user with an apology message (WinForms)
    • For a Service or a Console application: log it to a file (service or console)

Then I always enclose every piece of code that is run externally in try/catch :

  • All events fired by the WinForms infrastructure (Load, Click, SelectedChanged...)
  • All events fired by third party components

Then I enclose in 'try/catch'

  • All the operations that I know might not work all the time (IO operations, calculations with a potential zero division...). In such a case, I throw a new ApplicationException("custom message", innerException) to keep track of what really happened

Additionally, I try my best to sort exceptions correctly. There are exceptions which:

  • need to be shown to the user immediately

  • require some extra processing to put things together when they happen to avoid cascading problems (ie: put .EndUpdate in the finally section during a TreeView fill)

  • the user does not care, but it is important to know what happened. So I always log them:

  • In the event log

  • or in a .log file on the disk

It is a good practice to design some static methods to handle exceptions in the application top level error handlers.

I also force myself to try to:

  • Remember ALL exceptions are bubbled up to the top level. It is not necessary to put exception handlers everywhere.
  • Reusable or deep called functions does not need to display or log exceptions : they are either bubbled up automatically or rethrown with some custom messages in my exception handlers.

So finally:

Bad:

// DON'T DO THIS; ITS BAD
try
{
    ...
}
catch 
{
   // only air...
}

Useless:

// DON'T DO THIS; IT'S USELESS
try
{
    ...
}
catch(Exception ex)
{
    throw ex;
}

Having a try finally without a catch is perfectly valid:

try
{
    listView1.BeginUpdate();

    // If an exception occurs in the following code, then the finally will be executed
    // and the exception will be thrown
    ...
}
finally
{
    // I WANT THIS CODE TO RUN EVENTUALLY REGARDLESS AN EXCEPTION OCCURRED OR NOT
    listView1.EndUpdate();
}

What I do at the top level:

// i.e When the user clicks on a button
try
{
    ...
}
catch(Exception ex)
{
    ex.Log(); // Log exception

    -- OR --
    
    ex.Log().Display(); // Log exception, then show it to the user with apologies...
}

What I do in some called functions:

// Calculation module
try
{
    ...
}
catch(Exception ex)
{
    // Add useful information to the exception
    throw new ApplicationException("Something wrong happened in the calculation module:", ex);
}

// IO module
try
{
    ...
}
catch(Exception ex)
{
    throw new ApplicationException(string.Format("I cannot write the file {0} to {1}", fileName, directoryName), ex);
}

There is a lot to do with exception handling (Custom Exceptions) but those rules that I try to keep in mind are enough for the simple applications I do.

Here is an example of extensions methods to handle caught exceptions a comfortable way. They are implemented in a way they can be chained together, and it is very easy to add your own caught exception processing.

// Usage:

try
{
    // boom
}
catch(Exception ex)
{
    // Only log exception
    ex.Log();

    -- OR --

    // Only display exception
    ex.Display();

    -- OR --

    // Log, then display exception
    ex.Log().Display();

    -- OR --

    // Add some user-friendly message to an exception
    new ApplicationException("Unable to calculate !", ex).Log().Display();
}

// Extension methods

internal static Exception Log(this Exception ex)
{
    File.AppendAllText("CaughtExceptions" + DateTime.Now.ToString("yyyy-MM-dd") + ".log", DateTime.Now.ToString("HH:mm:ss") + ": " + ex.Message + "\n" + ex.ToString() + "\n");
    return ex;
}

internal static Exception Display(this Exception ex, string msg = null, MessageBoxImage img = MessageBoxImage.Error)
{
    MessageBox.Show(msg ?? ex.Message, "", MessageBoxButton.OK, img);
    return ex;
}

AngularJS: Insert HTML from a string

Have a look at the example in this link :

http://docs.angularjs.org/api/ngSanitize.$sanitize

Basically, angular has a directive to insert html into pages. In your case you can insert the html using the ng-bind-html directive like so :

If you already have done all this :

// My magic HTML string function.
function htmlString (str) {
    return "<h1>" + str + "</h1>";
}

function Ctrl ($scope) {
  var str = "HELLO!";
  $scope.htmlString = htmlString(str);
}
Ctrl.$inject = ["$scope"];

Then in your html within the scope of that controller, you could

<div ng-bind-html="htmlString"></div>

Rotating a Vector in 3D Space

If you want to rotate a vector you should construct what is known as a rotation matrix.

Rotation in 2D

Say you want to rotate a vector or a point by ?, then trigonometry states that the new coordinates are

    x' = x cos ? - y sin ?
    y' = x sin ? + y cos ?

To demo this, let's take the cardinal axes X and Y; when we rotate the X-axis 90° counter-clockwise, we should end up with the X-axis transformed into Y-axis. Consider

    Unit vector along X axis = <1, 0>
    x' = 1 cos 90 - 0 sin 90 = 0
    y' = 1 sin 90 + 0 cos 90 = 1
    New coordinates of the vector, <x', y'> = <0, 1>  ?  Y-axis

When you understand this, creating a matrix to do this becomes simple. A matrix is just a mathematical tool to perform this in a comfortable, generalized manner so that various transformations like rotation, scale and translation (moving) can be combined and performed in a single step, using one common method. From linear algebra, to rotate a point or vector in 2D, the matrix to be built is

    |cos ?   -sin ?| |x| = |x cos ? - y sin ?| = |x'|
    |sin ?    cos ?| |y|   |x sin ? + y cos ?|   |y'|

Rotation in 3D

That works in 2D, while in 3D we need to take in to account the third axis. Rotating a vector around the origin (a point) in 2D simply means rotating it around the Z-axis (a line) in 3D; since we're rotating around Z-axis, its coordinate should be kept constant i.e. 0° (rotation happens on the XY plane in 3D). In 3D rotating around the Z-axis would be

    |cos ?   -sin ?   0| |x|   |x cos ? - y sin ?|   |x'|
    |sin ?    cos ?   0| |y| = |x sin ? + y cos ?| = |y'|
    |  0       0      1| |z|   |        z        |   |z'|

around the Y-axis would be

    | cos ?    0   sin ?| |x|   | x cos ? + z sin ?|   |x'|
    |   0      1       0| |y| = |         y        | = |y'|
    |-sin ?    0   cos ?| |z|   |-x sin ? + z cos ?|   |z'|

around the X-axis would be

    |1     0           0| |x|   |        x        |   |x'|
    |0   cos ?    -sin ?| |y| = |y cos ? - z sin ?| = |y'|
    |0   sin ?     cos ?| |z|   |y sin ? + z cos ?|   |z'|

Note 1: axis around which rotation is done has no sine or cosine elements in the matrix.

Note 2: This method of performing rotations follows the Euler angle rotation system, which is simple to teach and easy to grasp. This works perfectly fine for 2D and for simple 3D cases; but when rotation needs to be performed around all three axes at the same time then Euler angles may not be sufficient due to an inherent deficiency in this system which manifests itself as Gimbal lock. People resort to Quaternions in such situations, which is more advanced than this but doesn't suffer from Gimbal locks when used correctly.

I hope this clarifies basic rotation.

Rotation not Revolution

The aforementioned matrices rotate an object at a distance r = v(x² + y²) from the origin along a circle of radius r; lookup polar coordinates to know why. This rotation will be with respect to the world space origin a.k.a revolution. Usually we need to rotate an object around its own frame/pivot and not around the world's i.e. local origin. This can also be seen as a special case where r = 0. Since not all objects are at the world origin, simply rotating using these matrices will not give the desired result of rotating around the object's own frame. You'd first translate (move) the object to world origin (so that the object's origin would align with the world's, thereby making r = 0), perform the rotation with one (or more) of these matrices and then translate it back again to its previous location. The order in which the transforms are applied matters. Combining multiple transforms together is called concatenation or composition.

Composition

I urge you to read about linear and affine transformations and their composition to perform multiple transformations in one shot, before playing with transformations in code. Without understanding the basic maths behind it, debugging transformations would be a nightmare. I found this lecture video to be a very good resource. Another resource is this tutorial on transformations that aims to be intuitive and illustrates the ideas with animation (caveat: authored by me!).

Rotation around Arbitrary Vector

A product of the aforementioned matrices should be enough if you only need rotations around cardinal axes (X, Y or Z) like in the question posted. However, in many situations you might want to rotate around an arbitrary axis/vector. The Rodrigues' formula (a.k.a. axis-angle formula) is a commonly prescribed solution to this problem. However, resort to it only if you’re stuck with just vectors and matrices. If you're using Quaternions, just build a quaternion with the required vector and angle. Quaternions are a superior alternative for storing and manipulating 3D rotations; it's compact and fast e.g. concatenating two rotations in axis-angle representation is fairly expensive, moderate with matrices but cheap in quaternions. Usually all rotation manipulations are done with quaternions and as the last step converted to matrices when uploading to the rendering pipeline. See Understanding Quaternions for a decent primer on quaternions.

Correct MIME Type for favicon.ico?

I have noticed that when using type="image/vnd.microsoft.icon", the favicon fails to appear when the browser is not connected to the internet. But type="image/x-icon" works whether the browser can connect to the internet, or not. When developing, at times I am not connected to the internet.

Include an SVG (hosted on GitHub) in MarkDown

I contacted GitHub to say that github.io-hosted SVGs are no longer displayed in GitHub READMEs. I received this reply:

We have had to disable svg image rendering on GitHub.com due to potential cross site scripting vulnerabilities.

Could not load type 'System.Runtime.CompilerServices.ExtensionAttribute' from assembly 'mscorlib

In my case, it was Blend SDK missed out on TeamCity machine. This caused the error due incorrect way of assembly resolving then.

How to get the top 10 values in postgresql?

Note that if there are ties in top 10 values, you will only get the top 10 rows, not the top 10 values with the answers provided. Ex: if the top 5 values are 10, 11, 12, 13, 14, 15 but your data contains 10, 10, 11, 12, 13, 14, 15 you will only get 10, 10, 11, 12, 13, 14 as your top 5 with a LIMIT

Here is a solution which will return more than 10 rows if there are ties but you will get all the rows where some_value_column is technically in the top 10.

select
  *
from
  (select
     *,
     rank() over (order by some_value_column desc) as my_rank
  from mytable) subquery
where my_rank <= 10

Add st, nd, rd and th (ordinal) suffix to a number

You can use the moment libraries local data functions.

Code:

moment.localeData().ordinal(1)
//1st

Entity Framework Migrations renaming tables and columns

To expand a bit on Hossein Narimani Rad's answer, you can rename both a table and columns using System.ComponentModel.DataAnnotations.Schema.TableAttribute and System.ComponentModel.DataAnnotations.Schema.ColumnAttribute respectively.

This has a couple benefits:

  1. Not only will this create the the name migrations automatically, but
  2. it will also deliciously delete any foreign keys and recreate them against the new table and column names, giving the foreign keys and constaints proper names.
  3. All this without losing any table data

For example, adding [Table("Staffs")]:

[Table("Staffs")]
public class AccountUser
{
    public long Id { get; set; }

    public long AccountId { get; set; }

    public string ApplicationUserId { get; set; }

    public virtual Account Account { get; set; }

    public virtual ApplicationUser User { get; set; }
}

Will generate the migration:

    protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.DropForeignKey(
            name: "FK_AccountUsers_Accounts_AccountId",
            table: "AccountUsers");

        migrationBuilder.DropForeignKey(
            name: "FK_AccountUsers_AspNetUsers_ApplicationUserId",
            table: "AccountUsers");

        migrationBuilder.DropPrimaryKey(
            name: "PK_AccountUsers",
            table: "AccountUsers");

        migrationBuilder.RenameTable(
            name: "AccountUsers",
            newName: "Staffs");

        migrationBuilder.RenameIndex(
            name: "IX_AccountUsers_ApplicationUserId",
            table: "Staffs",
            newName: "IX_Staffs_ApplicationUserId");

        migrationBuilder.RenameIndex(
            name: "IX_AccountUsers_AccountId",
            table: "Staffs",
            newName: "IX_Staffs_AccountId");

        migrationBuilder.AddPrimaryKey(
            name: "PK_Staffs",
            table: "Staffs",
            column: "Id");

        migrationBuilder.AddForeignKey(
            name: "FK_Staffs_Accounts_AccountId",
            table: "Staffs",
            column: "AccountId",
            principalTable: "Accounts",
            principalColumn: "Id",
            onDelete: ReferentialAction.Cascade);

        migrationBuilder.AddForeignKey(
            name: "FK_Staffs_AspNetUsers_ApplicationUserId",
            table: "Staffs",
            column: "ApplicationUserId",
            principalTable: "AspNetUsers",
            principalColumn: "Id",
            onDelete: ReferentialAction.Restrict);
    }

    protected override void Down(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.DropForeignKey(
            name: "FK_Staffs_Accounts_AccountId",
            table: "Staffs");

        migrationBuilder.DropForeignKey(
            name: "FK_Staffs_AspNetUsers_ApplicationUserId",
            table: "Staffs");

        migrationBuilder.DropPrimaryKey(
            name: "PK_Staffs",
            table: "Staffs");

        migrationBuilder.RenameTable(
            name: "Staffs",
            newName: "AccountUsers");

        migrationBuilder.RenameIndex(
            name: "IX_Staffs_ApplicationUserId",
            table: "AccountUsers",
            newName: "IX_AccountUsers_ApplicationUserId");

        migrationBuilder.RenameIndex(
            name: "IX_Staffs_AccountId",
            table: "AccountUsers",
            newName: "IX_AccountUsers_AccountId");

        migrationBuilder.AddPrimaryKey(
            name: "PK_AccountUsers",
            table: "AccountUsers",
            column: "Id");

        migrationBuilder.AddForeignKey(
            name: "FK_AccountUsers_Accounts_AccountId",
            table: "AccountUsers",
            column: "AccountId",
            principalTable: "Accounts",
            principalColumn: "Id",
            onDelete: ReferentialAction.Cascade);

        migrationBuilder.AddForeignKey(
            name: "FK_AccountUsers_AspNetUsers_ApplicationUserId",
            table: "AccountUsers",
            column: "ApplicationUserId",
            principalTable: "AspNetUsers",
            principalColumn: "Id",
            onDelete: ReferentialAction.Restrict);
    }

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder". in a Maven Project

I ran into this in IntelliJ and fixed it by adding the following to my pom:

<!-- logging dependencies -->
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>${logback.version}</version>
        <exclusions>
            <exclusion>
                <!-- Defined below -->
                <artifactId>slf4j-api</artifactId>
                <groupId>org.slf4j</groupId>
            </exclusion>
        </exclusions>
    </dependency>

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${slf4j.version}</version>
    </dependency>

Select a Column in SQL not in Group By

The columns in the result set of a select query with group by clause must be:

  • an expression used as one of the group by criteria , or ...
  • an aggregate function , or ...
  • a literal value

So, you can't do what you want to do in a single, simple query. The first thing to do is state your problem statement in a clear way, something like:

I want to find the individual claim row bearing the most recent creation date within each group in my claims table

Given

create table dbo.some_claims_table
(
  claim_id     int      not null ,
  group_id     int      not null ,
  date_created datetime not null ,

  constraint some_table_PK primary key ( claim_id                ) ,
  constraint some_table_AK01 unique    ( group_id , claim_id     ) ,
  constraint some_Table_AK02 unique    ( group_id , date_created ) ,

)

The first thing to do is identify the most recent creation date for each group:

select group_id ,
       date_created = max( date_created )
from dbo.claims_table
group by group_id

That gives you the selection criteria you need (1 row per group, with 2 columns: group_id and the highwater created date) to fullfill the 1st part of the requirement (selecting the individual row from each group. That needs to be a virtual table in your final select query:

select *
from dbo.claims_table t
join ( select group_id ,
       date_created = max( date_created )
       from dbo.claims_table
       group by group_id
      ) x on x.group_id     = t.group_id
         and x.date_created = t.date_created

If the table is not unique by date_created within group_id (AK02), you you can get duplicate rows for a given group.

click command in selenium webdriver does not work

This is a long standing issue with chromedriver(still present in 2020).

In Chrome I changed from a zoom of 90% to 100% and that solved the problem. ref

I find TheLifeOfSteve's answer more reliable.

100% width background image with an 'auto' height

Try this

html { 
  background: url(image.jpg) no-repeat center center fixed; 
  -webkit-background-size: cover;
     -moz-background-size: cover;
       -o-background-size: cover;
          background-size: cover;
}

Simplified version

html {
  background: url(image.jpg) center center / cover no-repeat fixed;
}

How do I fetch multiple columns for use in a cursor loop?

Here is slightly modified version. Changes are noted as code commentary.

BEGIN TRANSACTION

declare @cnt int
declare @test nvarchar(128)
-- variable to hold table name
declare @tableName nvarchar(255)
declare @cmd nvarchar(500) 
-- local means the cursor name is private to this code
-- fast_forward enables some speed optimizations
declare Tests cursor local fast_forward for
 SELECT COLUMN_NAME, TABLE_NAME
   FROM INFORMATION_SCHEMA.COLUMNS 
  WHERE COLUMN_NAME LIKE 'pct%' 
    AND TABLE_NAME LIKE 'TestData%'

open Tests
-- Instead of fetching twice, I rather set up no-exit loop
while 1 = 1
BEGIN
  -- And then fetch
  fetch next from Tests into @test, @tableName
  -- And then, if no row is fetched, exit the loop
  if @@fetch_status <> 0
  begin
     break
  end
  -- Quotename is needed if you ever use special characters
  -- in table/column names. Spaces, reserved words etc.
  -- Other changes add apostrophes at right places.
  set @cmd = N'exec sp_rename ''' 
           + quotename(@tableName) 
           + '.' 
           + quotename(@test) 
           + N''',''' 
           + RIGHT(@test,LEN(@test)-3) 
           + '_Pct''' 
           + N', ''column''' 

  print @cmd

  EXEC sp_executeSQL @cmd
END

close Tests 
deallocate Tests

ROLLBACK TRANSACTION
--COMMIT TRANSACTION

How to add number of days in postgresql datetime

For me I had to put the whole interval in single quotes not just the value of the interval.

select id,  
   title,
   created_at + interval '1 day' * claim_window as deadline from projects   

Instead of

select id,  
   title,
   created_at + interval '1' day * claim_window as deadline from projects   

Postgres Date/Time Functions

Uploading both data and files in one form using Ajax?

Or shorter:

$("form#data").submit(function() {
    var formData = new FormData(this);
    $.post($(this).attr("action"), formData, function() {
        // success    
    });
    return false;
});

change <audio> src with javascript

with jQuery:

 $("#playerSource").attr("src", "new_src");

    var audio = $("#player");      

    audio[0].pause();
    audio[0].load();//suspends and restores all audio element

    if (isAutoplay) 
        audio[0].play();

Why is Tkinter Entry's get function returning nothing?

*

master = Tk()
entryb1 = StringVar

Label(master, text="Input: ").grid(row=0, sticky=W)

Entry(master, textvariable=entryb1).grid(row=1, column=1)

b1 = Button(master, text="continue", command=print_content)
b1.grid(row=2, column=1)

def print_content():
    global entryb1
    content = entryb1.get()
    print(content)

master.mainloop()

What you did wrong was not put it inside a Define function then you hadn't used the .get function with the textvariable you had set.

How to align td elements in center

The best way to center content in a table (for example <video> or <img>) is to do the following:

_x000D_
_x000D_
<table width="100%" border="0" cellspacing="0" cellpadding="100%">
<tr>
<td>Video Tag 1 Here</td>
<td>Video Tag 2 Here</td>
</tr>
</table>
_x000D_
_x000D_
_x000D_

Why does the Google Play store say my Android app is incompatible with my own device?

Permissions that Imply Feature Requirements

example, the android.hardware.bluetooth feature was added in Android 2.2 (API level 8), but the bluetooth API that it refers to was added in Android 2.0 (API level 5). Because of this, some apps were able to use the API before they had the ability to declare that they require the API via the system.

To prevent those apps from being made available unintentionally, Google Play assumes that certain hardware-related permissions indicate that the underlying hardware features are required by default. For instance, applications that use Bluetooth must request the BLUETOOTH permission in a element — for legacy apps, Google Play assumes that the permission declaration means that the underlying android.hardware.bluetooth feature is required by the application and sets up filtering based on that feature.

The table below lists permissions that imply feature requirements equivalent to those declared in elements. Note that declarations, including any declared android:required attribute, always take precedence over features implied by the permissions below.

For any of the permissions below, you can disable filtering based on the implied feature by explicitly declaring the implied feature explicitly, in a element, with an android:required="false" attribute. For example, to disable any filtering based on the CAMERA permission, you would add this declaration to the manifest file:

<uses-feature android:name="android.hardware.camera" android:required="false" />


<uses-feature android:name="android.hardware.bluetooth" android:required="false" />
<uses-feature android:name="android.hardware.location" android:required="false" />
<uses-feature android:name="android.hardware.location.gps" android:required="false" />
<uses-feature android:name="android.hardware.telephony" android:required="false" />
<uses-feature android:name="android.hardware.wifi" android:required="false" />

http://developer.android.com/guide/topics/manifest/uses-feature-element.html#permissions

Safari 3rd party cookie iframe trick no longer working?

I recently hit the same issue on Safari. The solution I figured out is based on the Local Storage HTML5 API. Using Local Storage you could emulate cookies.

Here's my blog post with details: http://log.scalemotion.com/2012/10/how-to-trick-safari-and-set-3rd-party.html

How to add parameters to HttpURLConnection using POST using NameValuePair

One solution is to make your own params string.

This is the actual method I've been using for my latest project. You need to change args from hashtable to namevaluepair's:

private static String getPostParamString(Hashtable<String, String> params) {
    if(params.size() == 0)
        return "";

    StringBuffer buf = new StringBuffer();
    Enumeration<String> keys = params.keys();
    while(keys.hasMoreElements()) {
        buf.append(buf.length() == 0 ? "" : "&");
        String key = keys.nextElement();
        buf.append(key).append("=").append(params.get(key));
    }
    return buf.toString();
}

POSTing the params:

OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());
writer.write(getPostParamString(req.getPostParams()));

How to perform Join between multiple tables in LINQ lambda

 public ActionResult Index()
    {
        List<CustomerOrder_Result> obj = new List<CustomerOrder_Result>();

       var  orderlist = (from a in db.OrderMasters
                         join b in db.Customers on a.CustomerId equals b.Id
                         join c in db.CustomerAddresses on b.Id equals c.CustomerId
                         where a.Status == "Pending"
                         select new
                         {
                             Customername = b.Customername,
                             Phone = b.Phone,
                             OrderId = a.OrderId,
                             OrderDate = a.OrderDate,
                             NoOfItems = a.NoOfItems,
                             Order_amt = a.Order_amt,
                             dis_amt = a.Dis_amt,
                             net_amt = a.Net_amt,
                             status=a.Status,  
                             address = c.address,
                             City = c.City,
                             State = c.State,
                             Pin = c.Pin

                         }) ;
       foreach (var item in orderlist)
       {

           CustomerOrder_Result clr = new CustomerOrder_Result();
           clr.Customername=item.Customername;
           clr.Phone = item.Phone;
           clr.OrderId = item.OrderId;
           clr.OrderDate = item.OrderDate;
           clr.NoOfItems = item.NoOfItems;
           clr.Order_amt = item.Order_amt;
           clr.net_amt = item.net_amt;
           clr.address = item.address;
           clr.City = item.City;
           clr.State = item.State;
           clr.Pin = item.Pin;
           clr.status = item.status;

           obj.Add(clr);



       }

JSON to PHP Array using file_get_contents

The JSON sample you provided is not valid. Check it online with this JSON Validator http://jsonlint.com/. You need to remove the extra comma on line 59.

One you have valid json you can use this code to convert it to an array.

json_decode($json, true);

Array
(
    [bpath] => http://www.sampledomain.com/
    [clist] => Array
        (
            [0] => Array
                (
                    [cid] => 11
                    [display_type] => grid
                    [ctitle] => abc
                    [acount] => 71
                    [alist] => Array
                        (
                            [0] => Array
                                (
                                    [aid] => 6865
                                    [adate] => 2 Hours ago
                                    [atitle] => test
                                    [adesc] => test desc
                                    [aimg] => 
                                    [aurl] => ?nid=6865
                                    [weburl] => news.php?nid=6865
                                    [cmtcount] => 0
                                )

                            [1] => Array
                                (
                                    [aid] => 6857
                                    [adate] => 20 Hours ago
                                    [atitle] => test1
                                    [adesc] => test desc1
                                    [aimg] => 
                                    [aurl] => ?nid=6857
                                    [weburl] => news.php?nid=6857
                                    [cmtcount] => 0
                                )

                        )

                )

            [1] => Array
                (
                    [cid] => 1
                    [display_type] => grid
                    [ctitle] => test1
                    [acount] => 2354
                    [alist] => Array
                        (
                            [0] => Array
                                (
                                    [aid] => 6851
                                    [adate] => 1 Days ago
                                    [atitle] => test123
                                    [adesc] => test123 desc
                                    [aimg] => 
                                    [aurl] => ?nid=6851
                                    [weburl] => news.php?nid=6851
                                    [cmtcount] => 7
                                )

                            [1] => Array
                                (
                                    [aid] => 6847
                                    [adate] => 2 Days ago
                                    [atitle] => test12345
                                    [adesc] => test12345 desc
                                    [aimg] => 
                                    [aurl] => ?nid=6847
                                    [weburl] => news.php?nid=6847
                                    [cmtcount] => 7
                                )

                        )

                )

        )

)

Understanding the Linux oom-killer's logs

Sum of total_vm is 847170 and sum of rss is 214726, these two values are counted in 4kB pages, which means when oom-killer was running, you had used 214726*4kB=858904kB physical memory and swap space.

Since your physical memory is 1GB and ~200MB was used for memory mapping, it's reasonable for invoking oom-killer when 858904kB was used.

rss for process 2603 is 181503, which means 181503*4KB=726012 rss, was equal to sum of anon-rss and file-rss.

[11686.043647] Killed process 2603 (flasherav) total-vm:1498536kB, anon-rss:721784kB, file-rss:4228kB

Enable tcp\ip remote connections to sql server express already installed database with code or script(query)

I recommend to use SMO (Enable TCP/IP Network Protocol for SQL Server). However, it was not available in my case.

I rewrote the WMI commands from Krzysztof Kozielczyk to PowerShell.

# Enable TCP/IP

Get-CimInstance -Namespace root/Microsoft/SqlServer/ComputerManagement10 -ClassName ServerNetworkProtocol -Filter "InstanceName = 'SQLEXPRESS' and ProtocolName = 'Tcp'" |
Invoke-CimMethod -Name SetEnable

# Open the right ports in the firewall
New-NetFirewallRule -DisplayName 'MSSQL$SQLEXPRESS' -Direction Inbound -Action Allow -Protocol TCP -LocalPort 1433

# Modify TCP/IP properties to enable an IP address

$properties = Get-CimInstance -Namespace root/Microsoft/SqlServer/ComputerManagement10 -ClassName ServerNetworkProtocolProperty -Filter "InstanceName='SQLEXPRESS' and ProtocolName = 'Tcp' and IPAddressName='IPAll'"
$properties | ? { $_.PropertyName -eq 'TcpPort' } | Invoke-CimMethod -Name SetStringValue -Arguments @{ StrValue = '1433' }
$properties | ? { $_.PropertyName -eq 'TcpPortDynamic' } | Invoke-CimMethod -Name SetStringValue -Arguments @{ StrValue = '' }

# Restart SQL Server

Restart-Service 'MSSQL$SQLEXPRESS'

Is Django for the frontend or backend?

(a) Django is a framework, not a language

(b) I'm not sure what you're missing - there is no reason why you can't have business logic in a web application. In Django, you would normally expect presentation logic to be separated from business logic. Just because it is hosted in the same application server, it doesn't follow that the two layers are entangled.

(c) Django does provide templating, but it doesn't provide rich libraries for generating client-side content.

YouTube Video Embedded via iframe Ignoring z-index?

Just add one of these two to the src url:

&wmode=Opaque

&wmode=transparent

<iframe id="videoIframe" width="500" height="281" src="http://www.youtube.com/embed/xxxxxx?rel=0&wmode=transparent" frameborder="0" allowfullscreen></iframe>

Prevent div from moving while resizing the page

There are two types of measurements you can use for specifying widths, heights, margins etc: relative and fixed.

Relative

An example of a relative measurement is percentages, which you have used. Percentages are relevant to their containing element. If there is no containing element they are relative to the window.

<div style="width:100%"> 
<!-- This div will be the full width of the browser, whatever size it is -->
    <div style="width:300px">
    <!-- this div will be 300px, whatever size the browser is -->
        <p style="width:50%">
            This paragraph's width will be 50% of it's parent (150px).
        </p>
    </div>
</div>

Another relative measurement is ems which are relative to font size.

Fixed

An example of a fixed measurement is pixels but a fixed measurement can also be pt (points), cm (centimetres) etc. Fixed (sometimes called absolute) measurements are always the same size. A pixel is always a pixel, a centimetre is always a centimetre.

If you were to use fixed measurements for your sizes the browser size wouldn't affect the layout.

Correct way to use StringBuilder in SQL

You are correct in guessing that the aim of using string builder is not achieved, at least not to its full extent.

However, when the compiler sees the expression "select id1, " + " id2 " + " from " + " table" it emits code which actually creates a StringBuilder behind the scenes and appends to it, so the end result is not that bad afterall.

But of course anyone looking at that code is bound to think that it is kind of retarded.

Aborting a stash pop in Git

If you don't have to worry about any other changes you made and you just want to go back to the last commit, then you can do:

git reset .
git checkout .
git clean -f

How to create file object from URL object (image)

In order to create a File from a HTTP URL you need to download the contents from that URL:

URL url = new URL("http://www.google.ro/logos/2011/twain11-hp-bg.jpg");
URLConnection connection = url.openConnection();
InputStream in = connection.getInputStream();
FileOutputStream fos = new FileOutputStream(new File("downloaded.jpg"));
byte[] buf = new byte[512];
while (true) {
    int len = in.read(buf);
    if (len == -1) {
        break;
    }
    fos.write(buf, 0, len);
}
in.close();
fos.flush();
fos.close();

The downloaded file will be found at the root of your project: {project}/downloaded.jpg

How to solve SQL Server Error 1222 i.e Unlock a SQL Server table

To prevent this, make sure every BEGIN TRANSACTION has COMMIT

The following will say successful but will leave uncommitted transactions:

BEGIN TRANSACTION
BEGIN TRANSACTION
<SQL_CODE?
COMMIT

Closing query windows with uncommitted transactions will prompt you to commit your transactions. This will generally resolve the Error 1222 message.

XAMPP PORT 80 is Busy / EasyPHP error in Apache configuration file:

Port 80 might be busy with other application like IIS. If you don't want to stop it, you can change the apache port. Here is the way..

  1. go to the C:\xampp\apache\conf (directory where you installed xampp). Now, locate the httpd.conf.
  2. Open it with any text editor (like notepad) and go the line that says Listen 80
  3. Change this with any other port (like Listen 1234)
  4. Save the file. Restart the server and go ahead.

Drop-down menu that opens up/upward with pure css

Add bottom:100% to your #menu:hover ul li:hover ul rule

Demo 1

#menu:hover ul li:hover ul {
    position: absolute;
    margin-top: 1px;
    font: 10px;
    bottom: 100%; /* added this attribute */
}

Or better yet to prevent the submenus from having the same effect, just add this rule

Demo 2

#menu>ul>li:hover>ul { 
    bottom:100%;
}

Demo 3

source: http://jsfiddle.net/W5FWW/4/

And to get back the border you can add the following attribute

#menu>ul>li:hover>ul { 
    bottom:100%;
    border-bottom: 1px solid transparent
}

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed

If you don't want use connection pool (you sure, that your app has only one connection), you can do this - if connection falls you must establish new one - call method .openSession() instead .getCurrentSession()

For example:

SessionFactory sf = null;
// get session factory
// ...
//
Session session = null;
try {
        session = sessionFactory.getCurrentSession();
} catch (HibernateException ex) {
        session = sessionFactory.openSession();
}

If you use Mysql, you can set autoReconnect property:

    <property name="hibernate.connection.url">jdbc:mysql://127.0.0.1/database?autoReconnect=true</property>

I hope this helps.

ORA-01008: not all variables bound. They are bound

I know this is an old question, but it hasn't been correctly addressed, so I'm answering it for others who may run into this problem.

By default Oracle's ODP.net binds variables by position, and treats each position as a new variable.

Treating each copy as a different variable and setting it's value multiple times is a workaround and a pain, as furman87 mentioned, and could lead to bugs, if you are trying to rewrite the query and move things around.

The correct way is to set the BindByName property of OracleCommand to true as below:

var cmd = new OracleCommand(cmdtxt, conn);
cmd.BindByName = true;

You could also create a new class to encapsulate OracleCommand setting the BindByName to true on instantiation, so you don't have to set the value each time. This is discussed in this post

Replace "\\" with "\" in a string in C#

Try -

var newstring = @"a\\b".Replace(@"\\",@"\");

How can I make content appear beneath a fixed DIV element?

What you need is an extra spacing div (as far as I understood your question).

This div will be placed between the menu and content and be the same height as the menu div, paddings included.

HTML

<div id="fixed-menu">
    Navigation options or whatever.
</div>
<div class="spacer">
    &nbsp;
</div>
<div id="content">
    Content.
</div>

CSS

#fixed-menu
{
    position: fixed;
    width: 100%;
    height: 75px;
    background-color: #f00;
    padding: 10px;
}

.spacer
{
    width: 100%;
    height: 95px;
}

See my example here.

This works by offsetting the space that would have been occupied by the nav div, but as it has position: fixed; it has been taken out of the document flow.


The preferred method of achieving this effect is by using margin-top: 95px;/*your nav height*/ on your content wrapper.

TextView - setting the text size programmatically doesn't seem to work

In My Case Used this Method:

public static float pxFromDp(float dp, Context mContext) {
    return dp * mContext.getResources().getDisplayMetrics().density;
}

Here Set TextView's TextSize Programatically :

textView.setTextSize(pxFromDp(18, YourActivity.this));

Keep Enjoying:)

How can bcrypt have built-in salts?

This is from PasswordEncoder interface documentation from Spring Security,

 * @param rawPassword the raw password to encode and match
 * @param encodedPassword the encoded password from storage to compare with
 * @return true if the raw password, after encoding, matches the encoded password from
 * storage
 */
boolean matches(CharSequence rawPassword, String encodedPassword);

Which means, one will need to match rawPassword that user will enter again upon next login and matches it with Bcrypt encoded password that's stores in database during previous login/registration.

What's the correct way to convert bytes to a hex string in Python 3?

import codecs
codecs.getencoder('hex_codec')(b'foo')[0]

works in Python 3.3 (so "hex_codec" instead of "hex").

Best practice: PHP Magic Methods __set and __get

I do a mix of edem's answer and your second code. This way, I have the benefits of common getter/setters (code completion in your IDE), ease of coding if I want, exceptions due to inexistent properties (great for discovering typos: $foo->naem instead of $foo->name), read only properties and compound properties.

class Foo
{
    private $_bar;
    private $_baz;

    public function getBar()
    {
        return $this->_bar;
    }

    public function setBar($value)
    {
        $this->_bar = $value;
    }

    public function getBaz()
    {
        return $this->_baz;
    }

    public function getBarBaz()
    {
        return $this->_bar . ' ' . $this->_baz;
    }

    public function __get($var)
    {
        $func = 'get'.$var;
        if (method_exists($this, $func))
        {
            return $this->$func();
        } else {
            throw new InexistentPropertyException("Inexistent property: $var");
        }
    }

    public function __set($var, $value)
    {
        $func = 'set'.$var;
        if (method_exists($this, $func))
        {
            $this->$func($value);
        } else {
            if (method_exists($this, 'get'.$var))
            {
                throw new ReadOnlyException("property $var is read-only");
            } else {
                throw new InexistentPropertyException("Inexistent property: $var");
            }
        }
    }
}

How to remove multiple deleted files in Git repository

git status | sed 's/^#\s*deleted:\s*//' | sed 's/^#.*//' | xargs git rm -rf

Required attribute on multiple checkboxes with the same name?

Sorry, now I've read what you expected better, so I'm updating the answer.

Based on the HTML5 Specs from W3C, nothing is wrong. I created this JSFiddle test and it's behaving correctly based on the specs (for those browsers based on the specs, like Chrome 11 and Firefox 4):

_x000D_
_x000D_
<form>_x000D_
    <input type="checkbox" name="q" id="a-0" required autofocus>_x000D_
    <label for="a-0">a-1</label>_x000D_
    <br>_x000D_
_x000D_
    <input type="checkbox" name="q" id="a-1" required>_x000D_
    <label for="a-1">a-2</label>_x000D_
    <br>_x000D_
_x000D_
    <input type="checkbox" name="q" id="a-2" required>_x000D_
    <label for="a-2">a-3</label>_x000D_
    <br>_x000D_
_x000D_
    <input type="submit">_x000D_
</form>
_x000D_
_x000D_
_x000D_

I agree that it isn't very usable (in fact many people have complained about it in the W3C's mailing lists).

But browsers are just following the standard's recommendations, which is correct. The standard is a little misleading, but we can't do anything about it in practice. You can always use JavaScript for form validation, though, like some great jQuery validation plugin.

Another approach would be choosing a polyfill that can make (almost) all browsers interpret form validation rightly.

Android Pop-up message

Suppose you want to set a pop-up text box for clicking a button lets say bt whose id is button, then code using Toast will somewhat look like this:

Button bt;
bt = (Button) findViewById(R.id.button);
bt.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {            
Toast.makeText(getApplicationContext(),"The text you want to display",Toast.LENGTH_LONG)
}

MySQL OPTIMIZE all tables?

A starter bash script to list and run a tool against the DBs...

#!/bin/bash

declare -a dbs
unset opt

for each in $(echo "show databases;" | mysql -u root) ;do

        dbs+=($each)

done



echo " The system found [ ${#dbs[@]} ] databases." ;sleep 2
echo
echo "press 1 to run a check"
echo "press 2 to run an optimization"
echo "press 3 to run a repair"
echo "press 4 to run check,repair, and optimization"
echo "press q to quit"
read input

case $input in
        1) opt="-c"
        ;;
        2) opt="-o"
        ;;
        3) opt="-r"
        ;;
        4) opt="--auto-repair -c -o"
        ;;
        *) echo "Quitting Application .."; exit 7
        ;;
esac

[[ -z $opt ]] && exit 7;

echo " running option:  mysqlcheck $opt in 5 seconds  on all Dbs... "; sleep 5

for ((i=0; i<${#dbs[@]}; i++)) ;do
        echo "${dbs[$i]} : "
        mysqlcheck $opt ${dbs[$i]}  -u root
    done

Spaces in URLs?

The information there is I think partially correct:

That's not true. An URL can use spaces. Nothing defines that a space is replaced with a + sign.

As you noted, an URL can NOT use spaces. The HTTP request would get screwed over. I'm not sure where the + is defined, though %20 is standard.

Execution time of C program

If you are using the Unix shell for running, you can use the time command.

doing

$ time ./a.out

assuming a.out as the executable will give u the time taken to run this

How to add a custom right-click menu to a webpage?

Try this:

_x000D_
_x000D_
var cls = true;
var ops;

window.onload = function() {
    document.querySelector(".container").addEventListener("mouseenter", function() {
        cls = false;
    });
    document.querySelector(".container").addEventListener("mouseleave", function() {
        cls = true;
    });
    ops = document.querySelectorAll(".container td");
    for (let i = 0; i < ops.length; i++) {
        ops[i].addEventListener("click", function() {
            document.querySelector(".position").style.display = "none";
        });
    }

    /* IMPOSTARE LE VARIE OPZIONI */

    ops[0].addEventListener("click", function() {
        setTimeout(function() {
            /* YOUR FUNCTION */
            alert("Alert 1!");
        }, 50);
    });

    ops[1].addEventListener("click", function() {
        setTimeout(function() {
            /* YOUR FUNCTION */
            alert("Alert 2!");
        }, 50);
    });

    ops[2].addEventListener("click", function() {
        setTimeout(function() {
            /* YOUR FUNCTION */
            alert("Alert 3!");
        }, 50);
    });

    ops[3].addEventListener("click", function() {
        setTimeout(function() {
            /* YOUR FUNCTION */
            alert("Alert 4!");
        }, 50);
    });

    ops[4].addEventListener("click", function() {
        setTimeout(function() {
            /* YOUR FUNCTION */
            alert("Alert 5!");
        }, 50);
    });
}

document.addEventListener("contextmenu", function() {
    var e = window.event;
    e.preventDefault();
    document.querySelector(".container").style.padding = "0px";

    var x = e.clientX;
    var y = e.clientY;

    var docX = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth || document.body.offsetWidth;
    var docY = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight || document.body.offsetHeight;

    var border = parseInt(getComputedStyle(document.querySelector(".container"), null).getPropertyValue('border-width'));

    var objX = parseInt(getComputedStyle(document.querySelector(".container"), null).getPropertyValue('width')) + 2;
    var objY = parseInt(getComputedStyle(document.querySelector(".container"), null).getPropertyValue('height')) + 2;

    if (x + objX > docX) {
        let diff = (x + objX) - docX;
        x -= diff + border;
    }

    if (y + objY > docY) {
        let diff = (y + objY) - docY;
        y -= diff + border;
    }

    document.querySelector(".position").style.display = "block";

    document.querySelector(".position").style.top = y + "px";
    document.querySelector(".position").style.left = x + "px";
});

window.addEventListener("resize", function() {
    document.querySelector(".position").style.display = "none";
});

document.addEventListener("click", function() {
    if (cls) {
        document.querySelector(".position").style.display = "none";
    }
});

document.addEventListener("wheel", function() {
    if (cls) {
        document.querySelector(".position").style.display = "none";
        static = false;
    }
});
_x000D_
.position {
    position: absolute;
    width: 1px;
    height: 1px;
    z-index: 2;
    display: none;
}

.container {
    width: 220px;
    height: auto;
    border: 1px solid black;
    background: rgb(245, 243, 243);
}

.container p {
    height: 30px;
    font-size: 18px;
    font-family: arial;
    width: 99%;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    background: rgb(245, 243, 243);
    color: black;
    transition: 0.2s;
}

.container p:hover {
    background: lightblue;
}

td {
    font-family: arial;
    font-size: 20px;
}

td:hover {
    background: lightblue;
    transition: 0.2s;
    cursor: pointer;
}
_x000D_
<div class="position">
    <div class="container" align="center">
        <table style="text-align: left; width: 99%; margin-left: auto; margin-right: auto;" border="0" cellpadding="2" cellspacing="2">
            <tbody>
                <tr>
                    <td style="vertical-align: middle; text-align: center;">Option 1<br>
                    </td>
                </tr>
                <tr>
                    <td style="vertical-align: middle; text-align: center;">Option 2<br>
                    </td>
                </tr>
                <tr>
                    <td style="vertical-align: middle; text-align: center;">Option 3<br>
                    </td>
                </tr>
                <tr>
                    <td style="vertical-align: middle; text-align: center;">Option 4<br>
                    </td>
                </tr>
                <tr>
                    <td style="vertical-align: middle; text-align: center;">Option 5<br>
                    </td>
                </tr>
            </tbody>
        </table>
    </div>
</div>
_x000D_
_x000D_
_x000D_

Can't include C++ headers like vector in Android NDK

I'm using Android Studio and as of 19th of January 2016 this did the trick for me. (This seems like something that changes every year or so)

Go to: app -> Gradle Scripts -> build.gradle (Module: app)

Then under model { ... android.ndk { ... and add a line: stl = "gnustl_shared"

Like this:

model {

    ...

    android.ndk {
        moduleName = "gl2jni"
        cppFlags.add("-Werror")
        ldLibs.addAll(["log", "GLESv2"])
        stl = "gnustl_shared"     //  <-- this is the line that I added
    }

    ...

}

How to change the remote a branch is tracking?

Based on the git documentation the best way is:

  1. be sure the actual origin path:

git remote -v

  1. Then make the change with:

git remote set-url origin

where url-repository is the same URL that we get from the clone option.

Whitespace Matching Regex - Java

Seems to work for me:

String s = "  a   b      c";
System.out.println("\""  + s.replaceAll("\\s\\s", " ") + "\"");

will print:

" a  b   c"

I think you intended to do this instead of your code:

Pattern whitespace = Pattern.compile("\\s\\s");
Matcher matcher = whitespace.matcher(s);
String result = "";
if (matcher.find()) {
    result = matcher.replaceAll(" ");
}

System.out.println(result);

Using {% url ??? %} in django templates

The url template tag will pass the parameter as a string and not as a function reference to reverse(). The simplest way to get this working is adding a name to the view:

url(r'^/logout/' , logout_view, name='logout_view')

HashMap get/put complexity

HashMap operation is dependent factor of hashCode implementation. For the ideal scenario lets say the good hash implementation which provide unique hash code for every object (No hash collision) then the best, worst and average case scenario would be O(1). Let's consider a scenario where a bad implementation of hashCode always returns 1 or such hash which has hash collision. In this case the time complexity would be O(n).

Now coming to the second part of the question about memory, then yes memory constraint would be taken care by JVM.

Add or change a value of JSON key with jquery or javascript

Just like you would for any other variable, you just set it

alert(data.ID);
data.ID = "bar";  //dot notation 
alert(data.ID);    
data.userID = 123456;
data["address"] = "123 some street"; //bracket notation

Android read text raw resource file

Here goes mix of weekens's and Vovodroid's solutions.

It is more correct than Vovodroid's solution and more complete than weekens's solution.

    try {
        InputStream inputStream = res.openRawResource(resId);
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
            try {
                StringBuilder result = new StringBuilder();
                String line;
                while ((line = reader.readLine()) != null) {
                    result.append(line);
                }
                return result.toString();
            } finally {
                reader.close();
            }
        } finally {
            inputStream.close();
        }
    } catch (IOException e) {
        // process exception
    }

MySQL Foreign Key Error 1005 errno 150 primary key as foreign key

If your key is a CHAR/VARCHAR or something of that type, another possible problem is different collation. Check if the charset is the same.

Case-Insensitive List Search

Based on Adam Sills answer above - here's a nice clean extensions method for Contains... :)

///----------------------------------------------------------------------
/// <summary>
/// Determines whether the specified list contains the matching string value
/// </summary>
/// <param name="list">The list.</param>
/// <param name="value">The value to match.</param>
/// <param name="ignoreCase">if set to <c>true</c> the case is ignored.</param>
/// <returns>
///   <c>true</c> if the specified list contais the matching string; otherwise, <c>false</c>.
/// </returns>
///----------------------------------------------------------------------
public static bool Contains(this List<string> list, string value, bool ignoreCase = false)
{
    return ignoreCase ?
        list.Any(s => s.Equals(value, StringComparison.OrdinalIgnoreCase)) :
        list.Contains(value);
}

LINK : fatal error LNK1104: cannot open file 'D:\...\MyProj.exe'

Just to add another solution to the list, what I've found is that Visual Studio (2012 in my case) occasionally locks files under different processes.

So, on a crash, devenv.exe might still be running and holding onto the file(s). Alternatively (as I just discovered), vstestrunner or vstestdiscovery might be holding onto the file as well.

Kill all those processes and it might fix up the issue.

understanding private setters

With the introduction of C# 6.0 and the syntax for Auto-Property Initializers, private setters are no longer needed for properties that are only set upon initialization, either inline or within the constructor.

These new syntaxes now compile:

Inline initialized property

public class MyClass1 {
  public string MyProperty { get; } = "Aloha!"
}

Constructor initialized property

public class MyClass2 {
  public string MyProperty { get; }

  public MyClass2(string myProperty) {
    MyProperty = myProperty;
  }
}

Address already in use: JVM_Bind

Your local port 443 / 8181 / 3820 is used.

If you are on linux/unix:

  • use netstat -an and lsof -n to check who is using this port

If you are on windows

  • use netstat -an and tcpview to check.

How to convert DateTime to/from specific string format (both ways, e.g. given Format is "yyyyMMdd")?

Simply just do in this way.

string yourFormat = DateTime.Now.ToString("yyyyMMdd");

Happy coding :)

Pad with leading zeros

You can do this with a string datatype. Use the PadLeft method:

var myString = "1";
myString = myString.PadLeft(myString.Length + 5, '0');

000001

Difference between acceptance test and functional test?

Acceptance testing is just testing carried out by the client, and includes other kinds of testing:

  • Functional testing: "this button doesn't work"
  • Non-functional testing: "this page works but is too slow"

For functional testing vs non-functional testing (their subtypes) - see my answer to this SO question.

CLEAR SCREEN - Oracle SQL Developer shortcut?

Use cl scr on the Sql* command line tool to clear all the matter on the screen.

How can I solve "Either the parameter @objname is ambiguous or the claimed @objtype (COLUMN) is wrong."?

Are you running the query in the correct database? i.e.,

Use MyDatabase;
GO
EXEC sp_rename 'ENG_TEst.[ENG_Test_A/C_TYPE]', 'ENG_Test_AC_TYPE', 'COLUMN';
GO

Dealing with HTTP content in HTTPS pages

Sometimes like in facebook apps we can not have non-secure contents in secure page. also we can not make local those contents. for example an app which will load in iFrame is not a simple content and we can not make it local.

I think we should never load http contents in https, also we should not fallback https page to http version to prevent error dialog.

the only way which will ensure user's security is to use https version of all contents, http://web.archive.org/web/20120502131549/http://developers.facebook.com/blog/post/499/

jQuery Validation using the class instead of the name value

Here's the solution using jQuery:

    $().ready(function () {
        $(".formToValidate").validate();
        $(".checkBox").each(function (item) {
            $(this).rules("add", {
                required: true,
                minlength:3
            });
        });
    });

Match groups in Python

Starting Python 3.8, and the introduction of assignment expressions (PEP 572) (:= operator), we can now capture the condition value re.search(pattern, statement) in a variable (let's all it match) in order to both check if it's not None and then re-use it within the body of the condition:

if match := re.search('I love (\w+)', statement):
  print(f'He loves {match.group(1)}')
elif match := re.search("Ich liebe (\w+)", statement):
  print(f'Er liebt {match.group(1)}')
elif match := re.search("Je t'aime (\w+)", statement):
  print(f'Il aime {match.group(1)}')

Python vs Bash - In which kind of tasks each one outruns the other performance-wise?

Typical mainframe flow...

Input Disk/Tape/User (runtime) --> Job Control Language (JCL) --> Output Disk/Tape/Screen/Printer
                                   |                          ^
                                   v                          |
                                   `--> COBOL Program --------' 

Typical Linux flow...

Input Disk/SSD/User (runtime) --> sh/bash/ksh/zsh/... ----------> Output Disk/SSD/Screen/Printer
                                   |                          ^
                                   v                          |
                                   `--> Python script --------'
                                   |                          ^
                                   v                          |
                                   `--> awk script -----------'
                                   |                          ^
                                   v                          |
                                   `--> sed script -----------'
                                   |                          ^
                                   v                          |
                                   `--> C/C++ program --------'
                                   |                          ^
                                   v                          |
                                   `--- Java program ---------'
                                   |                          ^
                                   v                          |
                                   :                          :

Shells are the glue of Linux

Linux shells like sh/ksh/bash/... provide input/output/flow-control designation facilities much like the old mainframe Job Control Language... but on steroids! They are Turing complete languages in their own right while being optimized to efficiently pass data and control to and from other executing processes written in any language the O/S supports.

Most Linux applications, regardless what language the bulk of the program is written in, depend on shell scripts and Bash has become the most common. Clicking an icon on the desktop usually runs a short Bash script. That script, either directly or indirectly, knows where all the files needed are and sets variables and command line parameters, finally calling the program. That's a shell's simplest use.

Linux as we know it however would hardly be Linux without the thousands of shell scripts that startup the system, respond to events, control execution priorities and compile, configure and run programs. Many of these are quite large and complex.

Shells provide an infrastructure that lets us use pre-built components that are linked together at run time rather than compile time. Those components are free-standing programs in their own right that can be used alone or in other combinations without recompiling. The syntax for calling them is indistinguishable from that of a Bash builtin command, and there are in fact numerous builtin commands for which there is also a stand-alone executable on the system, often having additional options.

There is no language-wide difference between Python and Bash in performance. It entirely depends on how each is coded and which external tools are called.

Any of the well known tools like awk, sed, grep, bc, dc, tr, etc. will leave doing those operations in either language in the dust. Bash then is preferred for anything without a graphical user interface since it is easier and more efficient to call and pass data back from a tool like those with Bash than Python.

Performance

It depends on which programs the Bash shell script calls and their suitability for the subtask they are given whether the overall throughput and/or responsiveness will be better or worse than the equivalent Python. To complicate matters Python, like most languages, can also call other executables, though it is more cumbersome and thus not as often used.

User Interface

One area where Python is the clear winner is user interface. That makes it an excellent language for building local or client-server applications as it natively supports GTK graphics and is far more intuitive than Bash.

Bash only understands text. Other tools must be called for a GUI and data passed back from them. A Python script is one option. Faster but less flexible options are the binaries like YAD, Zenity, and GTKDialog.

While shells like Bash work well with GUIs like Yad, GtkDialog (embedded XML-like interface to GTK+ functions), dialog, and xmessage, Python is much more capable and so better for complex GUI windows.

Summary

Building with shell scripts is like assembling a computer with off-the-shelf components the way desktop PCs are.

Building with Python, C++ or most any other language is more like building a computer by soldering the chips (libraries) and other electronic parts together the way smartphones are.

The best results are usually obtained by using a combination of languages where each can do what they do best. One developer calls this "polyglot programming".

Why is it bad practice to call System.gc()?

Yes, calling System.gc() doesn't guarantee that it will run, it's a request to the JVM that may be ignored. From the docs:

Calling the gc method suggests that the Java Virtual Machine expend effort toward recycling unused objects

It's almost always a bad idea to call it because the automatic memory management usually knows better than you when to gc. It will do so when its internal pool of free memory is low, or if the OS requests some memory be handed back.

It might be acceptable to call System.gc() if you know that it helps. By that I mean you've thoroughly tested and measured the behaviour of both scenarios on the deployment platform, and you can show it helps. Be aware though that the gc isn't easily predictable - it may help on one run and hurt on another.

Service has zero application (non-infrastructure) endpoints

I just worked through this issue on my service. Here is the error I was receiving:

Service 'EmailSender.Wcf.EmailService' has zero application (non-infrastructure) endpoints. This might be because no configuration file was found for your application, or because no service element matching the service name could be found in the configuration file, or because no endpoints were defined in the service element.

Here are the two steps I used to fix it:

  1. Use the correct fully-qualified class name:

    <service behaviorConfiguration="DefaultBehavior" name="EmailSender.Wcf.EmailService">
    
  2. Enable an endpoint with mexHttpBinding, and most importantly, use the IMetadataExchange contract:

    <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
    

Force drop mysql bypassing foreign key constraint

Since you are not interested in keeping any data, drop the entire database and create a new one.

How to evaluate http response codes from bash/shell script?

this can help to evaluate http status

var=`curl -I http://www.example.org 2>/dev/null | head -n 1 | awk -F" " '{print $2}'`
echo http:$var

Change the maximum upload file size

the answers are a bit incomplete, 3 things you have to do

in php.ini of your php installation (note: depending if you want it for CLI, apache, or nginx, find the right php.ini to manipulate. For nginx it is usually located in /etc/php/7.1/fpm where 7.1 depends on your version. For apache usually /etc/php/7.1/apache2)

post_max_size=500M

upload_max_filesize=500M

memory_limit=900M

or set other values. Restart/reload apache if you have apache installed or php-fpm for nginx if you use nginx.

HTTPS connection Python

To check for ssl support in Python 2.6+:

try:
    import ssl
except ImportError:
    print "error: no ssl support"

To connect via https:

import urllib2

try:
    response = urllib2.urlopen('https://example.com') 
    print 'response headers: "%s"' % response.info()
except IOError, e:
    if hasattr(e, 'code'): # HTTPError
        print 'http error code: ', e.code
    elif hasattr(e, 'reason'): # URLError
        print "can't connect, reason: ", e.reason
    else:
        raise

Questions every good PHP Developer should be able to answer

When a site is developed using php and it's utter crap, is it:

a) PHPs fault

b) Programmers fault

Questions every good Java/Java EE Developer should be able to answer?

If you are hiring graduates with Java "experience" a simple question like Write some code that will cause a NullPointerException to be thrown can distinguish which candidates have used Java recently, and didn't just stop when they finished their unit/course.

What exactly do "u" and "r" string flags do, and what are raw string literals?

Let me explain it simply: In python 2, you can store string in 2 different types.

The first one is ASCII which is str type in python, it uses 1 byte of memory. (256 characters, will store mostly English alphabets and simple symbols)

The 2nd type is UNICODE which is unicode type in python. Unicode stores all types of languages.

By default, python will prefer str type but if you want to store string in unicode type you can put u in front of the text like u'text' or you can do this by calling unicode('text')

So u is just a short way to call a function to cast str to unicode. That's it!

Now the r part, you put it in front of the text to tell the computer that the text is raw text, backslash should not be an escaping character. r'\n' will not create a new line character. It's just plain text containing 2 characters.

If you want to convert str to unicode and also put raw text in there, use ur because ru will raise an error.

NOW, the important part:

You cannot store one backslash by using r, it's the only exception. So this code will produce error: r'\'

To store a backslash (only one) you need to use '\\'

If you want to store more than 1 characters you can still use r like r'\\' will produce 2 backslashes as you expected.

I don't know the reason why r doesn't work with one backslash storage but the reason isn't described by anyone yet. I hope that it is a bug.

How can one develop iPhone apps in Java?

Even if the question states Java, most of the answers have digressed. So I thought I would do the same :)

We have been using Adobe AIR for the last 5 years and it is truly cross-platform and provides native-like performance with the same code base (at least 99% of our code is the same). Adobe AIR got some bad press at the beginning during the 'beta' period (slow, no GPU, Flash 'dead' etc.) But now, it's amazing what you can do with it. Not to mention the wealth of open source libs out there.

With the same code base you can push your app onto:

  • iOS
  • Android (x86 and ARM)
  • Flash (still VERY useful)
  • ChromeBook
  • PC (as native with installer)
  • Mac (as native with installer)

Why bother with Java or Objective-C ?

The only common platform not covered is Window Phone. But that's coming soon too.

MySQL Multiple Left Joins

You're missing a GROUP BY clause:

SELECT news.id, users.username, news.title, news.date, news.body, COUNT(comments.id)
FROM news
LEFT JOIN users
ON news.user_id = users.id
LEFT JOIN comments
ON comments.news_id = news.id
GROUP BY news.id

The left join is correct. If you used an INNER or RIGHT JOIN then you wouldn't get news items that didn't have comments.

HintPath vs ReferencePath in Visual Studio

According to this MSDN blog: https://blogs.msdn.microsoft.com/manishagarwal/2005/09/28/resolving-file-references-in-team-build-part-2/

There is a search order for assemblies when building. The search order is as follows:

  • Files from the current project – indicated by ${CandidateAssemblyFiles}.
  • $(ReferencePath) property that comes from .user/targets file.
  • %(HintPath) metadata indicated by reference item.
  • Target framework directory.
  • Directories found in registry that uses AssemblyFoldersEx Registration.
  • Registered assembly folders, indicated by ${AssemblyFolders}.
  • $(OutputPath) or $(OutDir)
  • GAC

So, if the desired assembly is found by HintPath, but an alternate assembly can be found using ReferencePath, it will prefer the ReferencePath'd assembly to the HintPath'd one.

Testing web application on Mac/Safari when I don't own a Mac

The best site to test website and see them realtime on MAC Safari is by using

Browserstack

They have like 25 free minutes of first time testing and then 10 free mins each day..You can even test your pages from your local PC by using their WEB TUNNEL Feature

I tested 7 to 8 pages in browserstack...And I think they have some java debugging tool in the upper right corner that is great help

CKEditor instance already exists

Its pretty simple. In my case, I ran the below jquery method that will destroy ckeditor instances during a page load. This did the trick and resolved the issue -

JQuery method -

function resetCkEditorsOnLoad(){

    for(var i in CKEDITOR.instances) {
        editor = CKEDITOR.instances[i];
            editor.destroy();
            editor = null;
    }
}

$(function() {

            $(".form-button").button();
    $(".button").button();

    resetCkEditorsOnLoad(); // CALLING THE METHOD DURING THE PAGE LOAD

            .... blah.. blah.. blah.... // REST OF YOUR BUSINESS LOGIC GOES HERE

       });

That's it. I hope it helps you.

Cheers, Sirish.

Is the Scala 2.8 collections library a case of "the longest suicide note in history"?

I do not have a PhD, nor any other kind of degree neither in CS nor math nor indeed any other field. I have no prior experience with Scala nor any other similar language. I have no experience with even remotely comparable type systems. In fact, the only language that I have more than just a superficial knowledge of which even has a type system is Pascal, not exactly known for its sophisticated type system. (Although it does have range types, which AFAIK pretty much no other language has, but that isn't really relevant here.) The other three languages I know are BASIC, Smalltalk and Ruby, none of which even have a type system.

And yet, I have no trouble at all understanding the signature of the map function you posted. It looks to me like pretty much the same signature that map has in every other language I have ever seen. The difference is that this version is more generic. It looks more like a C++ STL thing than, say, Haskell. In particular, it abstracts away from the concrete collection type by only requiring that the argument is IterableLike, and also abstracts away from the concrete return type by only requiring that an implicit conversion function exists which can build something out of that collection of result values. Yes, that is quite complex, but it really is only an expression of the general paradigm of generic programming: do not assume anything that you don't actually have to.

In this case, map does not actually need the collection to be a list, or being ordered or being sortable or anything like that. The only thing that map cares about is that it can get access to all elements of the collection, one after the other, but in no particular order. And it does not need to know what the resulting collection is, it only needs to know how to build it. So, that is what its type signature requires.

So, instead of

map :: (a ? b) ? [a] ? [b]

which is the traditional type signature for map, it is generalized to not require a concrete List but rather just an IterableLike data structure

map :: (IterableLike i, IterableLike j) ? (a ? b) ? i ? j

which is then further generalized by only requiring that a function exists that can convert the result to whatever data structure the user wants:

map :: IterableLike i ? (a ? b) ? i ? ([b] ? c) ? c

I admit that the syntax is a bit clunkier, but the semantics are the same. Basically, it starts from

def map[B](f: (A) ? B): List[B]

which is the traditional signature for map. (Note how due to the object-oriented nature of Scala, the input list parameter vanishes, because it is now the implicit receiver parameter that every method in a single-dispatch OO system has.) Then it generalized from a concrete List to a more general IterableLike

def map[B](f: (A) ? B): IterableLike[B]

Now, it replaces the IterableLike result collection with a function that produces, well, really just about anything.

def map[B, That](f: A ? B)(implicit bf: CanBuildFrom[Repr, B, That]): That

Which I really believe is not that hard to understand. There's really only a couple of intellectual tools you need:

  1. You need to know (roughly) what map is. If you gave only the type signature without the name of the method, I admit, it would be a lot harder to figure out what is going on. But since you already know what map is supposed to do, and you know what its type signature is supposed to be, you can quickly scan the signature and focus on the anomalies, like "why does this map take two functions as arguments, not one?"
  2. You need to be able to actually read the type signature. But even if you have never seen Scala before, this should be quite easy, since it really is just a mixture of type syntaxes you already know from other languages: VB.NET uses square brackets for parametric polymorphism, and using an arrow to denote the return type and a colon to separate name and type, is actually the norm.
  3. You need to know roughly what generic programming is about. (Which isn't that hard to figure out, since it's basically all spelled out in the name: it's literally just programming in a generic fashion).

None of these three should give any professional or even hobbyist programmer a serious headache. map has been a standard function in pretty much every language designed in the last 50 years, the fact that different languages have different syntax should be obvious to anyone who has designed a website with HTML and CSS and you can't subscribe to an even remotely programming related mailinglist without some annoying C++ fanboy from the church of St. Stepanov explaining the virtues of generic programming.

Yes, Scala is complex. Yes, Scala has one of the most sophisticated type systems known to man, rivaling and even surpassing languages like Haskell, Miranda, Clean or Cyclone. But if complexity were an argument against success of a programming language, C++ would have died long ago and we would all be writing Scheme. There are lots of reasons why Scala will very likely not be successful, but the fact that programmers can't be bothered to turn on their brains before sitting down in front of the keyboard is probably not going to be the main one.

Faking an RS232 Serial Port

I use com0com - With Signed Driver, on windows 7 x64 to emulate COM3 AND COM4 as a pair.

Then i use COM Dataport Emulator to recieve from COM4.

Then i open COM3 with the app im developping (c#) and send data to COM3.

The data sent thru COM3 is received by COM4 and shown by 'COM Dataport Emulator' who can also send back a response (not automated).

So with this 2 great programs i managed to emulate Serial RS-232 comunication.

Hope it helps.

Both programs are free!!!!!

How do I indent multiple lines at once in Notepad++?

If you're using QuickText and like pressing Tab for it, you can otherwise change the indentation key.

Go Settings > Shortcup Mapper > Scintilla Command. Look at the number 10.

  • I changed 10 to : CTRL + ALT + RIGHT and
  • 11 to : CTRL+ ALT+ LEFT.

Now I think it's even better than the TABL / SHIFT + TAB as default.

Is the NOLOCK (Sql Server hint) bad practice?

Prior to working on Stack Overflow, I was against NOLOCK on the principal that you could potentially perform a SELECT with NOLOCK and get back results with data that may be out of date or inconsistent. A factor to think about is how many records may be inserted/updated at the same time another process may be selecting data from the same table. If this happens a lot then there's a high probability of deadlocks unless you use a database mode such as READ COMMITED SNAPSHOT.

I have since changed my perspective on the use of NOLOCK after witnessing how it can improve SELECT performance as well as eliminate deadlocks on a massively loaded SQL Server. There are times that you may not care that your data isn't exactly 100% committed and you need results back quickly even though they may be out of date.

Ask yourself a question when thinking of using NOLOCK:

Does my query include a table that has a high number of INSERT/UPDATE commands and do I care if the data returned from a query may be missing these changes at a given moment?

If the answer is no, then use NOLOCK to improve performance.


I just performed a quick search for the NOLOCK keyword within the code base for Stack Overflow and found 138 instances, so we use it in quite a few places.

SQL "select where not in subquery" returns no results

SELECT T.common_id
  FROM Common T
       LEFT JOIN Table1 T1 ON T.common_id = T1.common_id
       LEFT JOIN Table2 T2 ON T.common_id = T2.common_id
 WHERE T1.common_id IS NULL
   AND T2.common_id IS NULL

TSQL Pivot without aggregate function

yes, but why !!??

   Select CustomerID,
     Min(Case DBColumnName When 'FirstName' Then Data End) FirstName,
     Min(Case DBColumnName When 'MiddleName' Then Data End) MiddleName,
     Min(Case DBColumnName When 'LastName' Then Data End) LastName,
     Min(Case DBColumnName When 'Date' Then Data End) Date
   From table
   Group By CustomerId

How do I check if I'm running on Windows in Python?

in sys too:

import sys
# its win32, maybe there is win64 too?
is_windows = sys.platform.startswith('win')

MySQL InnoDB not releasing disk space after deleting data rows from table

MySQL doesn't reduce the size of ibdata1. Ever. Even if you use optimize table to free the space used from deleted records, it will reuse it later.

An alternative is to configure the server to use innodb_file_per_table, but this will require a backup, drop database and restore. The positive side is that the .ibd file for the table is reduced after an optimize table.

Expand a div to fill the remaining width

If both of the widths are variable length why don't you calculate the width with some scripting or server side?

<div style="width: <=% getTreeWidth() %>">Tree</div>

<div style="width: <=% getViewWidth() %>">View</div>

Verify object attribute value with mockito

And very nice and clean solution in koltin from com.nhaarman.mockito_kotlin

verify(mock).execute(argThat {
    this.param = expected
})

Is embedding background image data into CSS as Base64 good or bad practice?

One of the things I would suggest is to have two separate stylesheets: One with your regular style definitions and another one that contains your images in base64 encoding.

You have to include the base stylesheet before the image stylesheet of course.

This way you will assure that you're regular stylesheet is downloaded and applied as soon as possible to the document, yet at the same time you profit from reduced http-requests and other benefits data-uris give you.

What does Ruby have that Python doesn't, and vice versa?

I'm unsure of this, so I add it as an answer first.

Python treats unbound methods as functions

That means you can call a method either like theobject.themethod() or by TheClass.themethod(anobject).

Edit: Although the difference between methods and functions is small in Python, and non-existant in Python 3, it also doesn't exist in Ruby, simply because Ruby doesn't have functions. When you define functions, you are actually defining methods on Object.

But you still can't take the method of one class and call it as a function, you would have to rebind it to the object you want to call on, which is much more obstuse.

Is a Java hashmap search really O(1)?

It is O(1) only if your hashing function is very good. The Java hash table implementation does not protect against bad hash functions.

Whether you need to grow the table when you add items or not is not relevant to the question because it is about lookup time.

Changing the action of a form with JavaScript/jQuery

I agree with Paolo that we need to see more code. I tested this overly simplified example and it worked. This means that it is able to change the form action on the fly.

<script type="text/javascript">
function submitForm(){
    var form_url = $("#openid_form").attr("action");
    alert("Before - action=" + form_url);   
    //changing the action to google.com
    $("#openid_form").attr("action","http://google.com");
    alert("After - action = "+$("#openid_form").attr("action"));
    //submit the form
    $("#openid_form").submit();
}
</script>


<form id="openid_form" action="test.html">
    First Name:<input type="text" name="fname" /><br/>
    Last Name: <input type="text" name="lname" /><br/>
    <input type="button" onclick="submitForm()" value="Submit Form" />
</form>

EDIT: I tested the updated code you posted and found a syntax error in the declaration of providers_large. There's an extra comma. Firefox ignores the issue, but IE8 throws an error.

var providers_large = {
    google: {
        name: 'Google',
        url: 'https://www.google.com/accounts/o8/id'
    },
    facebook: {
        name: 'Facebook',
        form_url: 'http://wikipediamaze.rpxnow.com/facebook/start?token_url=http://www.wikipediamaze.com/Accounts/Logon'
    },  //<-- Here's the problem. Remove that comma

};

Changing the current working directory in Java?

The other possible answer to this question may depend on the reason you are opening the file. Is this a property file or a file that has some configuration related to your application?

If this is the case you may consider trying to load the file through the classpath loader, this way you can load any file Java has access to.

Why is document.write considered a "bad practice"?

Browser Violation

.write is considered a browser violation as it halts the parser from rendering the page. The parser receives the message that the document is being modified; hence, it gets blocked until JS has completed its process. Only at this time will the parser resume.

Performance

The biggest consequence of employing such a method is lowered performance. The browser will take longer to load page content. The adverse reaction on load time depends on what is being written to the document. You won't see much of a difference if you are adding a <p> tag to the DOM as opposed to passing an array of 50-some references to JavaScript libraries (something which I have seen in working code and resulted in an 11 second delay - of course, this also depends on your hardware).

All in all, it's best to steer clear of this method if you can help it.

For more info see Intervening against document.write()

Consistency of hashCode() on a Java string

I can see that documentation as far back as Java 1.2.

While it's true that in general you shouldn't rely on a hash code implementation remaining the same, it's now documented behaviour for java.lang.String, so changing it would count as breaking existing contracts.

Wherever possible, you shouldn't rely on hash codes staying the same across versions etc - but in my mind java.lang.String is a special case simply because the algorithm has been specified... so long as you're willing to abandon compatibility with releases before the algorithm was specified, of course.

XSLT counting elements with a given value

Your xpath is just a little off:

count(//Property/long[text()=$parPropId])

Edit: Cerebrus quite rightly points out that the code in your OP (using the implicit value of a node) is absolutely fine for your purposes. In fact, since it's quite likely you want to work with the "Property" node rather than the "long" node, it's probably superior to ask for //Property[long=$parPropId] than the text() xpath, though you could make a case for the latter on readability grounds.

What can I say, I'm a bit tired today :)

Getting a 'source: not found' error when using source in a bash script

In Ubuntu if you execute the script with sh scriptname.sh you get this problem.

Try executing the script with ./scriptname.sh instead.

Is double square brackets [[ ]] preferable over single square brackets [ ] in Bash?

Behavior differences

Some differences on Bash 4.3.11:

  • POSIX vs Bash extension:

  • regular command vs magic

    • [ is just a regular command with a weird name.

      ] is just the last argument of [.

    Ubuntu 16.04 actually has an executable for it at /usr/bin/[ provided by coreutils, but the bash built-in version takes precedence.

    Nothing is altered in the way that Bash parses the command.

    In particular, < is redirection, && and || concatenate multiple commands, ( ) generates subshells unless escaped by \, and word expansion happens as usual.

    • [[ X ]] is a single construct that makes X be parsed magically. <, &&, || and () are treated specially, and word splitting rules are different.

      There are also further differences like = and =~.

    In Bashese: [ is a built-in command, and [[ is a keyword: https://askubuntu.com/questions/445749/whats-the-difference-between-shell-builtin-and-shell-keyword

  • <

  • && and ||

    • [[ a = a && b = b ]]: true, logical and
    • [ a = a && b = b ]: syntax error, && parsed as an AND command separator cmd1 && cmd2
    • [ a = a ] && [ b = b ]: POSIX reliable equivalent
    • [ a = a -a b = b ]: almost equivalent, but deprecated by POSIX because it is insane and fails for some values of a or b like ! or ( which would be interpreted as logical operations
  • (

    • [[ (a = a || a = b) && a = b ]]: false. Without ( ), would be true because [[ && ]] has greater precedence than [[ || ]]
    • [ ( a = a ) ]: syntax error, () is interpreted as a subshell
    • [ \( a = a -o a = b \) -a a = b ]: equivalent, but (), -a, and -o are deprecated by POSIX. Without \( \) would be true because -a has greater precedence than -o
    • { [ a = a ] || [ a = b ]; } && [ a = b ] non-deprecated POSIX equivalent. In this particular case however, we could have written just: [ a = a ] || [ a = b ] && [ a = b ] because the || and && shell operators have equal precedence unlike [[ || ]] and [[ && ]] and -o, -a and [
  • word splitting and filename generation upon expansions (split+glob)

    • x='a b'; [[ $x = 'a b' ]]: true, quotes not needed
    • x='a b'; [ $x = 'a b' ]: syntax error, expands to [ a b = 'a b' ]
    • x='*'; [ $x = 'a b' ]: syntax error if there's more than one file in the current directory.
    • x='a b'; [ "$x" = 'a b' ]: POSIX equivalent
  • =

    • [[ ab = a? ]]: true, because it does pattern matching (* ? [ are magic). Does not glob expand to files in current directory.
    • [ ab = a? ]: a? glob expands. So may be true or false depending on the files in the current directory.
    • [ ab = a\? ]: false, not glob expansion
    • = and == are the same in both [ and [[, but == is a Bash extension.
    • case ab in (a?) echo match; esac: POSIX equivalent
    • [[ ab =~ 'ab?' ]]: false, loses magic with '' in Bash 3.2 and above and provided compatibility to bash 3.1 is not enabled (like with BASH_COMPAT=3.1)
    • [[ ab? =~ 'ab?' ]]: true
  • =~

    • [[ ab =~ ab? ]]: true, POSIX extended regular expression match, ? does not glob expand
    • [ a =~ a ]: syntax error. No bash equivalent.
    • printf 'ab\n' | grep -Eq 'ab?': POSIX equivalent (single line data only)
    • awk 'BEGIN{exit !(ARGV[1] ~ ARGV[2])}' ab 'ab?': POSIX equivalent.

Recommendation: always use []

There are POSIX equivalents for every [[ ]] construct I've seen.

If you use [[ ]] you:

  • lose portability
  • force the reader to learn the intricacies of another bash extension. [ is just a regular command with a weird name, no special semantics are involved.

Thanks to Stéphane Chazelas for important corrections and additions.

When is assembly faster than C?

Tight loops, like when playing with images, since an image may cosist of millions of pixels. Sitting down and figuring out how to make best use of the limited number of processor registers can make a difference. Here's a real life sample:

http://danbystrom.se/2008/12/22/optimizing-away-ii/

Then often processors have some esoteric instructions which are too specialized for a compiler to bother with, but on occasion an assembler programmer can make good use of them. Take the XLAT instruction for example. Really great if you need to do table look-ups in a loop and the table is limited to 256 bytes!

Updated: Oh, just come to think of what's most crucial when we speak of loops in general: the compiler has often no clue on how many iterations that will be the common case! Only the programmer know that a loop will be iterated MANY times and that it therefore will be beneficial to prepare for the loop with some extra work, or if it will be iterated so few times that the set-up actually will take longer than the iterations expected.

How can I match multiple occurrences with a regex in JavaScript similar to PHP's preg_match_all()?

To avoid regex hell you could find your first match, chop off a chunk then attempt to find the next one on the substring. In C# this looks something like this, sorry I've not ported it over to JavaScript for you.

        long count = 0;
        var remainder = data;
        Match match = null;
        do
        {
            match = _rgx.Match(remainder);
            if (match.Success)
            {
                count++;
                remainder = remainder.Substring(match.Index + 1, remainder.Length - (match.Index+1));
            }
        } while (match.Success);
        return count;

Performance of Arrays vs. Lists

Since List<> uses arrays internally, the basic performance should be the same. Two reasons, why the List might be slightly slower:

  • To look up a element in the list, a method of List is called, which does the look up in the underlying array. So you need an additional method call there. On the other hand the compiler might recognize this and optimize the "unnecessary" call away.
  • The compiler might do some special optimizations if it knows the size of the array, that it can't do for a list of unknown length. This might bring some performance improvement if you only have a few elements in your list.

To check if it makes any difference for you, it's probably best adjust the posted timing functions to a list of the size you're planning to use and see how the results for your special case are.

Avoid synchronized(this) in Java?

The reason not to synchronize on this is that sometimes you need more than one lock (the second lock often gets removed after some additional thinking, but you still need it in the intermediate state). If you lock on this, you always have to remember which one of the two locks is this; if you lock on a private Object, the variable name tells you that.

From the reader's viewpoint, if you see locking on this, you always have to answer the two questions:

  1. what kind of access is protected by this?
  2. is one lock really enough, didn't someone introduce a bug?

An example:

class BadObject {
    private Something mStuff;
    synchronized setStuff(Something stuff) {
        mStuff = stuff;
    }
    synchronized getStuff(Something stuff) {
        return mStuff;
    }
    private MyListener myListener = new MyListener() {
        public void onMyEvent(...) {
            setStuff(...);
        }
    }
    synchronized void longOperation(MyListener l) {
        ...
        l.onMyEvent(...);
        ...
    }
}

If two threads begin longOperation() on two different instances of BadObject, they acquire their locks; when it's time to invoke l.onMyEvent(...), we have a deadlock because neither of the threads may acquire the other object's lock.

In this example we may eliminate the deadlock by using two locks, one for short operations and one for long ones.

Troubleshooting "program does not contain a static 'Main' method" when it clearly does...?

In my case (where none of the proposed solutions fit), the problem was I used async/await where the signature for main method looked this way:

static async void Main(string[] args)

I simply removed async so the main method looked this way:

static void Main(string[] args)

I also removed all instances of await and used .Result for async calls, so my console application could compile happily.

Can a Byte[] Array be written to a file in C#?

Asp.net (c#)

// This is server path, where application is hosted.

var path = @"C:\Websites\mywebsite\profiles\";

//file in bytes array

var imageBytes = client.DownloadData(imagePath);

//file extension

var fileExtension = System.IO.Path.GetExtension(imagePath);

//writing(saving) the files on given path. Appending employee id as file name and file extension.

File.WriteAllBytes(path + dataTable.Rows[0]["empid"].ToString() + fileExtension, imageBytes);

Next Step:

You may need to Provide access to profile folder for iis user.

  1. right click on profile folder
  2. go to security tab
  3. click "Edit",
  4. give full control to "IIS_IUSRS" (IF THIS USER NOT EXISTS THEN CLICK ON ADD AND TYPE "IIS_IUSRS" AND CLICK ON "Check Names".

How to define a preprocessor symbol in Xcode

You don't need to create a user-defined setting. The built-in setting "Preprocessor Macros" works just fine. alt text http://idisk.mac.com/cdespinosa/Public/Picture%204.png

If you have multiple targets or projects that use the same prefix file, use Preprocessor Macros Not Used In Precompiled Headers instead, so differences in your macro definition don't trigger an unnecessary extra set of precompiled headers.

Does functional programming replace GoF design patterns?

As others have said, there are patterns specific to functional programming. I think the issue of getting rid of design patterns is not so much a matter of switching to functional, but a matter of language features.

Take a look at how Scala does away with the "singleton pattern": you simply declare an object instead of a class. Another feature, pattern matching, helps avoiding the clunkiness of the visitor pattern. See the comparison here: Scala's Pattern Matching = Visitor Pattern on Steroids

And Scala, like F#, is a fusion of OO-functional. I don't know about F#, but it probably has these kind of features.

Closures are present in functional language, but they need not be restricted to them. They help with the delegator pattern.

One more observation. This piece of code implements a pattern: it's such a classic and it's so elemental that we don't usually think of it as a "pattern", but it sure is:

for(int i = 0; i < myList.size(); i++) { doWhatever(myList.get(i)); }

Imperative languages like Java and C# have adopted what is essentially a functional construct to deal with this: "foreach".

Git for beginners: The definitive practical guide

WRT good GUIs/frontends, you may also want to check out qgit which is a cross-platform (Linux/Win32) repository viewer for Git and can be also used as high level frontend for the most common Git operations, in fact it can be easily enhanced by so called "custom actions" so that users can provide customized actions.

How do I change the default application icon in Java?

java.net.URL url = ClassLoader.getSystemResource("com/xyz/resources/camera.png");

May or may not require a '/' at the front of the path.

How do I rename a column in a database table using SQL?

Specifically for SQL Server, use sp_rename

USE AdventureWorks;
GO
EXEC sp_rename 'Sales.SalesTerritory.TerritoryID', 'TerrID', 'COLUMN';
GO

How do you do Impersonation in .NET?

View more detail from my previous answer I have created an nuget package Nuget

Code on Github

sample : you can use :

           string login = "";
           string domain = "";
           string password = "";

           using (UserImpersonation user = new UserImpersonation(login, domain, password))
           {
               if (user.ImpersonateValidUser())
               {
                   File.WriteAllText("test.txt", "your text");
                   Console.WriteLine("File writed");
               }
               else
               {
                   Console.WriteLine("User not connected");
               }
           }

Vieuw the full code :

using System;
using System.Runtime.InteropServices;
using System.Security.Principal;


/// <summary>
/// Object to change the user authticated
/// </summary>
public class UserImpersonation : IDisposable
{
    /// <summary>
    /// Logon method (check athetification) from advapi32.dll
    /// </summary>
    /// <param name="lpszUserName"></param>
    /// <param name="lpszDomain"></param>
    /// <param name="lpszPassword"></param>
    /// <param name="dwLogonType"></param>
    /// <param name="dwLogonProvider"></param>
    /// <param name="phToken"></param>
    /// <returns></returns>
    [DllImport("advapi32.dll")]
    private static extern bool LogonUser(String lpszUserName,
        String lpszDomain,
        String lpszPassword,
        int dwLogonType,
        int dwLogonProvider,
        ref IntPtr phToken);

    /// <summary>
    /// Close
    /// </summary>
    /// <param name="handle"></param>
    /// <returns></returns>
    [DllImport("kernel32.dll", CharSet = CharSet.Auto)]
    public static extern bool CloseHandle(IntPtr handle);

    private WindowsImpersonationContext _windowsImpersonationContext;
    private IntPtr _tokenHandle;
    private string _userName;
    private string _domain;
    private string _passWord;

    const int LOGON32_PROVIDER_DEFAULT = 0;
    const int LOGON32_LOGON_INTERACTIVE = 2;

    /// <summary>
    /// Initialize a UserImpersonation
    /// </summary>
    /// <param name="userName"></param>
    /// <param name="domain"></param>
    /// <param name="passWord"></param>
    public UserImpersonation(string userName, string domain, string passWord)
    {
        _userName = userName;
        _domain = domain;
        _passWord = passWord;
    }

    /// <summary>
    /// Valiate the user inforamtion
    /// </summary>
    /// <returns></returns>
    public bool ImpersonateValidUser()
    {
        bool returnValue = LogonUser(_userName, _domain, _passWord,
                LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT,
                ref _tokenHandle);

        if (false == returnValue)
        {
            return false;
        }

        WindowsIdentity newId = new WindowsIdentity(_tokenHandle);
        _windowsImpersonationContext = newId.Impersonate();
        return true;
    }

    #region IDisposable Members

    /// <summary>
    /// Dispose the UserImpersonation connection
    /// </summary>
    public void Dispose()
    {
        if (_windowsImpersonationContext != null)
            _windowsImpersonationContext.Undo();
        if (_tokenHandle != IntPtr.Zero)
            CloseHandle(_tokenHandle);
    }

    #endregion
}

is the + operator less performant than StringBuffer.append()

Try this:

var s = ["<a href='", url, "'>click here</a>"].join("");

What are some resources for getting started in operating system development?

you also might want to take a look at SharpOS which is an operating system that they're writing in c#.

Is Java "pass-by-reference" or "pass-by-value"?

Just to show the contrast, compare the following C++ and Java snippets:

In C++: Note: Bad code - memory leaks! But it demonstrates the point.

void cppMethod(int val, int &ref, Dog obj, Dog &objRef, Dog *objPtr, Dog *&objPtrRef)
{
    val = 7; // Modifies the copy
    ref = 7; // Modifies the original variable
    obj.SetName("obj"); // Modifies the copy of Dog passed
    objRef.SetName("objRef"); // Modifies the original Dog passed
    objPtr->SetName("objPtr"); // Modifies the original Dog pointed to 
                               // by the copy of the pointer passed.
    objPtr = new Dog("newObjPtr");  // Modifies the copy of the pointer, 
                                   // leaving the original object alone.
    objPtrRef->SetName("objRefPtr"); // Modifies the original Dog pointed to 
                                    // by the original pointer passed. 
    objPtrRef = new Dog("newObjPtrRef"); // Modifies the original pointer passed
}

int main()
{
    int a = 0;
    int b = 0;
    Dog d0 = Dog("d0");
    Dog d1 = Dog("d1");
    Dog *d2 = new Dog("d2");
    Dog *d3 = new Dog("d3");
    cppMethod(a, b, d0, d1, d2, d3);
    // a is still set to 0
    // b is now set to 7
    // d0 still have name "d0"
    // d1 now has name "objRef"
    // d2 now has name "objPtr"
    // d3 now has name "newObjPtrRef"
}

In Java,

public static void javaMethod(int val, Dog objPtr)
{
   val = 7; // Modifies the copy
   objPtr.SetName("objPtr") // Modifies the original Dog pointed to 
                            // by the copy of the pointer passed.
   objPtr = new Dog("newObjPtr");  // Modifies the copy of the pointer, 
                                  // leaving the original object alone.
}

public static void main()
{
    int a = 0;
    Dog d0 = new Dog("d0");
    javaMethod(a, d0);
    // a is still set to 0
    // d0 now has name "objPtr"
}

Java only has the two types of passing: by value for built-in types, and by value of the pointer for object types.

Python: Differentiating between row and column vectors

row vectors are (1,0) tensor, vectors are (0, 1) tensor. if using v = np.array([[1,2,3]]), v become (0,2) tensor. Sorry, i am confused.

Correct way to detach from a container without stopping it

You can simply kill docker cli process by sending SEGKILL. If you started the container with

docker run -it some/container

You can get it's pid

ps -aux | grep docker

user   1234  0.3  0.6 1357948 54684 pts/2   Sl+  15:09   0:00 docker run -it some/container

let's say it's 1234, you can "detach" it with

kill -9 1234

It's somewhat of a hack but it works!

Difference between iCalendar (.ics) and the vCalendar (.vcs)

The newer iCalendar format, with more data attached, includes information about the person who created the event, so that when it is imported into Outlook (for example), changes to that event are communicated via email to the creator. This can be helpful when you need to inform others of any changes.

However, when I am just exporting an event from one of my calendars to another, I prefer to use vCalendar, since this does not require sending an email message to the creator (usually myself) if I make a change or delete something.

How to make gradient background in android

Use this code in drawable folder.

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="#3f5063" />
    <corners
        android:bottomLeftRadius="30dp"
        android:bottomRightRadius="0dp"
        android:topLeftRadius="30dp"
        android:topRightRadius="0dp" />
    <padding
        android:bottom="2dp"
        android:left="2dp"
        android:right="2dp"
        android:top="2dp" />
    <gradient
        android:angle="45"
        android:centerColor="#015664"
        android:endColor="#636969"
        android:startColor="#2ea4e7" />
    <stroke
        android:width="1dp"
        android:color="#000000" />
</shape>

Passing an Object from an Activity to a Fragment

This one worked for me:

In Activity:

User user;
public User getUser(){ return this.user;}

In Fragment's onCreateView method:

User user = ((MainActivity)getActivity()).getUser(); 

Replace the MainActivity with your Activity Name.

Detect all Firefox versions in JS

here it it

var ffversion = '18';
var is_firefox = navigator.userAgent.toLowerCase().indexOf('firefox/'+ffversion) > -1;
alert(is_firefox);

Add spaces between the characters of a string in Java?

I am creating a java method for this purpose with dynamic character

public String insertSpace(String myString,int indexno,char myChar){
    myString=myString.substring(0, indexno)+ myChar+myString.substring(indexno);
    System.out.println(myString);
    return myString;
}

Check if url contains string with JQuery

Use Window.location.href to take the url in javascript. it's a property that will tell you the current URL location of the browser. Setting the property to something different will redirect the page.

if (window.location.href.indexOf("?added-to-cart=555") > -1) {
    alert("found it");
}

Can you autoplay HTML5 videos on the iPad?

Let video muted first to ensure autoplay in ios, then unmute it if you want.

<video autoplay loop muted playsinline>
  <source src="video.mp4?123" type="video/mp4">
</video>

<script type="text/javascript">
$(function () {
  if (!navigator.userAgent.match(/(iPod|iPhone|iPad)/)) {
    $("video").prop('muted', false);
  }
});
</script>

Multi-threading in VBA

I am adding this answer since programmers coming to VBA from more modern languages and searching Stack Overflow for multithreading in VBA might be unaware of a couple of native VBA approaches which sometimes help to compensate for VBA's lack of true multithreading.

If the motivation of multithreading is to have a more responsive UI that doesn't hang when long-running code is executing, VBA does have a couple of low-tech solutions that often work in practice:

1) Userforms can be made to display modelessly - which allows the user to interact with Excel while the form is open. This can be specified at runtime by setting the Userform's ShowModal property to false or can be done dynamically as the from loads by putting the line

UserForm1.Show vbModeless

in the user form's initialize event.

2) The DoEvents statement. This causes VBA to cede control to the OS to execute any events in the events queue - including events generated by Excel. A typical use-case is updating a chart while code is executing. Without DoEvents the chart won't be repainted until after the macro is run, but with Doevents you can create animated charts. A variation of this idea is the common trick of creating a progress meter. In a loop which is to execute 10,000,000 times (and controlled by the loop index i ) you can have a section of code like:

If i Mod 10000 = 0 Then
    UpdateProgressBar(i) 'code to update progress bar display
    DoEvents
End If

None of this is multithreading -- but it might be an adequate kludge in some cases.

C non-blocking keyboard input

The curses library can be used for this purpose. Of course, select() and signal handlers can be used too to a certain extent.

Cancel split window in Vim

Press Control+w, then hit q to close each window at a time.

Update: Also consider eckes answer which may be more useful to you, involving :on (read below) if you don't want to do it one window at a time.

Pass Additional ViewData to a Strongly-Typed Partial View

I think this should work no?

ViewData["currentIndex"] = index;

How to play video with AVPlayerViewController (AVKit) in Swift

Swift 5

  @IBAction func buttonPressed(_ sender: Any) {
    let videoURL = course.introductionVideoURL
    let player = AVPlayer(url: videoURL)
    let playerViewController = AVPlayerViewController()
    playerViewController.player = player

    present(playerViewController, animated: true, completion: {

        playerViewController.player!.play()
    })

// here the course includes a model file, inside it I have given the url, so I am calling the function from model using course function.

// also introductionVideoUrl is a URL which I declared inside model .

 var introductionVideoURL: URL

Also alternatively you can use the below code instead of calling the function from model

Replace this code

  let videoURL = course.introductionVideoURL

with

  guard let videoURL = URL(string: "https://something.mp4) else {
        return

Accessing AppDelegate from framework?

If you're creating a framework the whole idea is to make it portable. Tying a framework to the app delegate defeats the purpose of building a framework. What is it you need the app delegate for?

macro - open all files in a folder

Try the below code:

Sub opendfiles()

Dim myfile As Variant
Dim counter As Integer
Dim path As String

myfolder = "D:\temp\"
ChDir myfolder
myfile = Application.GetOpenFilename(, , , , True)
counter = 1
If IsNumeric(myfile) = True Then
    MsgBox "No files selected"
End If
While counter <= UBound(myfile)
    path = myfile(counter)
    Workbooks.Open path
    counter = counter + 1
Wend

End Sub

Auto select file in Solution Explorer from its open tab

Another option is to bind 'View.TrackActivityInSolutionExplorer' to a keyboard short-cut, which is the same as 'Tools-->Options-->Projects and Solutions-->Track Active Item in Solution Explorer'

If you activate the short-cut twice the file is selected in the solution explorer, and the tracking is disabled again.

Visual Studio 2013+

There is now a feature built in to the VS2013 solution explorer called Sync with Active Document. The icon is two arrows in the solution explorer, and has the hotkey Ctrl + [, S to show the current document in the solution explorer. Does not enable the automatic setting mentioned above, and only happens once.

How do I read from parameters.yml in a controller in symfony2?

The Clean Way - 2018+, Symfony 3.4+

Since 2017 and Symfony 3.3 + 3.4 there is much cleaner way - easy to setup and use.

Instead of using container and service/parameter locator anti-pattern, you can pass parameters to class via it's constructor. Don't worry, it's not time-demanding work, but rather setup once & forget approach.

How to set it up in 2 steps?

1. app/config/services.yml

# config.yml

# config.yml
parameters:
    api_pass: 'secret_password'
    api_user: 'my_name'

services:
    _defaults:
        autowire: true
        bind:
            $apiPass: '%api_pass%'
            $apiUser: '%api_user%'

    App\:
        resource: ..

2. Any Controller

<?php declare(strict_types=1);

final class ApiController extends SymfonyController
{
    /**
     * @var string 
     */
    private $apiPass;

    /**
     * @var string
     */
    private $apiUser;

    public function __construct(string $apiPass, string $apiUser)
    {
        $this->apiPass = $apiPass;
        $this->apiUser = $apiUser;
    }

    public function registerAction(): void
    {
        var_dump($this->apiPass); // "secret_password"
        var_dump($this->apiUser); // "my_name"
    }
}

Instant Upgrade Ready!

In case you use older approach, you can automate it with Rector.

Read More

This is called constructor injection over services locator approach.

To read more about this, check my post How to Get Parameter in Symfony Controller the Clean Way.

(It's tested and I keep it updated for new Symfony major version (5, 6...)).

"make clean" results in "No rule to make target `clean'"

You have fallen victim to the most common of errors in Makefiles. You always need to put a Tab at the beginning of each command. You've put spaces before the $(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS) and @rm -f $(PROGRAMS) *.o core lines. If you replace them with a Tab, you'll be fine.

However, this error doesn't lead to a "No rule to make target ..." error. That probably means your issue lies beyond your Makefile. Have you checked this is the correct Makefile, as in the one you want to be specifying your commands? Try explicitly passing it as a parameter to make, make -f Makefile and let us know what happens.

Displaying Windows command prompt output and redirecting it to a file

Unfortunately there is no such thing.

Windows console applications only have a single output handle. (Well, there are two STDOUT, STDERR but it doesn't matter here) The > redirects the output normally written to the console handle to a file handle.

If you want to have some kind of multiplexing you have to use an external application which you can divert the output to. This application then can write to a file and to the console again.

Get a random item from a JavaScript array

Here's yet another way:

function rand(items) {
    // "~~" for a closest "int"
    return items[~~(items.length * Math.random())];
}

Or as recommended below by @1248177:

function rand(items) {
    // "|" for a kinda "int div"
    return items[items.length * Math.random() | 0];
}

how to display employee names starting with a and then b in sql

If you're asking about alphabetical order the syntax is:

SELECT * FROM table ORDER BY column

the best example I can give without knowing your table and field names:

SELECT * FROM employees ORDER BY name

Shell Script Syntax Error: Unexpected End of File

You've got an unclosed quote, brace, bracket, if, loop, or something.

If you can't see it just by looking (I'd recommend a syntax colouring editor and a neat indentation style), take a copy of the script, and delete half of it, cutting it of somewhere that ought to be valid. If the script runs, as far as it can, then the problem is in the other half. Repeat until you've narrowed down the problem.

What's the difference between xsd:include and xsd:import?

Direct quote from MSDN: <xsd:import> Element, Remarks section

The difference between the include element and the import element is that import element allows references to schema components from schema documents with different target namespaces and the include element adds the schema components from other schema documents that have the same target namespace (or no specified target namespace) to the containing schema. In short, the import element allows you to use schema components from any schema; the include element allows you to add all the components of an included schema to the containing schema.

How do I accomplish an if/else in mustache.js?

You can define a helper in the view. However, the conditional logic is somewhat limited. Moxy-Stencil (https://github.com/dcmox/moxyscript-stencil) seems to address this with "parameterized" helpers, eg:

{{isActive param}}

and in the view:

view.isActive = function (path: string){ return path === this.path ? "class='active'" : '' }

How to add dividers and spaces between items in RecyclerView?

Implement its own version of RecyclerView.ItemDecoration

public class SpacingItemDecoration extends RecyclerView.ItemDecoration {
    private int spacingPx;
    private boolean addStartSpacing;
    private boolean addEndSpacing;

    public SpacingItemDecoration(int spacingPx) {
        this(spacingPx, false, false);
    }

    public SpacingItemDecoration(int spacingPx, boolean addStartSpacing, boolean addEndSpacing) {
        this.spacingPx = spacingPx;
        this.addStartSpacing = addStartSpacing;
        this.addEndSpacing = addEndSpacing;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        super.getItemOffsets(outRect, view, parent, state);
        if (spacingPx <= 0) {
            return;
        }

        if (addStartSpacing && parent.getChildLayoutPosition(view) < 1 || parent.getChildLayoutPosition(view) >= 1) {
            if (getOrientation(parent) == LinearLayoutManager.VERTICAL) {
                outRect.top = spacingPx;
            } else {
                outRect.left = spacingPx;
            }
        }

        if (addEndSpacing && parent.getChildAdapterPosition(view) == getTotalItemCount(parent) - 1) {
            if (getOrientation(parent) == LinearLayoutManager.VERTICAL) {
                outRect.bottom = spacingPx;
            } else {
                outRect.right = spacingPx;
            }
        }
    }

    private int getTotalItemCount(RecyclerView parent) {
        return parent.getAdapter().getItemCount();
    }

    private int getOrientation(RecyclerView parent) {
        if (parent.getLayoutManager() instanceof LinearLayoutManager) {
            return ((LinearLayoutManager) parent.getLayoutManager()).getOrientation();
        } else {
            throw new IllegalStateException("SpacingItemDecoration can only be used with a LinearLayoutManager.");
        }
    }
}

How to unpack an .asar file?

From the asar documentation

(the use of npx here is to avoid to install the asar tool globally with npm install -g asar)

Extract the whole archive:

npx asar extract app.asar destfolder 

Extract a particular file:

npx asar extract-file app.asar main.js

How to convert a string from uppercase to lowercase in Bash?

If you define your variable using declare (old: typeset) then you can state the case of the value throughout the variable's use.

$ declare -u FOO=AbCxxx
$ echo $FOO
ABCXXX

"-l" does lc.

multiprocessing.Pool: When to use apply, apply_async or map?

Back in the old days of Python, to call a function with arbitrary arguments, you would use apply:

apply(f,args,kwargs)

apply still exists in Python2.7 though not in Python3, and is generally not used anymore. Nowadays,

f(*args,**kwargs)

is preferred. The multiprocessing.Pool modules tries to provide a similar interface.

Pool.apply is like Python apply, except that the function call is performed in a separate process. Pool.apply blocks until the function is completed.

Pool.apply_async is also like Python's built-in apply, except that the call returns immediately instead of waiting for the result. An AsyncResult object is returned. You call its get() method to retrieve the result of the function call. The get() method blocks until the function is completed. Thus, pool.apply(func, args, kwargs) is equivalent to pool.apply_async(func, args, kwargs).get().

In contrast to Pool.apply, the Pool.apply_async method also has a callback which, if supplied, is called when the function is complete. This can be used instead of calling get().

For example:

import multiprocessing as mp
import time

def foo_pool(x):
    time.sleep(2)
    return x*x

result_list = []
def log_result(result):
    # This is called whenever foo_pool(i) returns a result.
    # result_list is modified only by the main process, not the pool workers.
    result_list.append(result)

def apply_async_with_callback():
    pool = mp.Pool()
    for i in range(10):
        pool.apply_async(foo_pool, args = (i, ), callback = log_result)
    pool.close()
    pool.join()
    print(result_list)

if __name__ == '__main__':
    apply_async_with_callback()

may yield a result such as

[1, 0, 4, 9, 25, 16, 49, 36, 81, 64]

Notice, unlike pool.map, the order of the results may not correspond to the order in which the pool.apply_async calls were made.


So, if you need to run a function in a separate process, but want the current process to block until that function returns, use Pool.apply. Like Pool.apply, Pool.map blocks until the complete result is returned.

If you want the Pool of worker processes to perform many function calls asynchronously, use Pool.apply_async. The order of the results is not guaranteed to be the same as the order of the calls to Pool.apply_async.

Notice also that you could call a number of different functions with Pool.apply_async (not all calls need to use the same function).

In contrast, Pool.map applies the same function to many arguments. However, unlike Pool.apply_async, the results are returned in an order corresponding to the order of the arguments.

Could not find com.android.tools.build:gradle:3.0.0-alpha1 in circle ci

To synchronize all of the answers here and elsewhere:

buildscript {
  repositories {
    google() 
    jcenter()
  }
  dependencies {
    classpath 'com.android.tools.build:gradle:3.0.0'

  } }

Make your buildscript in build.gradle look like this. It finds all of them between google and jcenter. Only one of them will not find all of the dependencies as of this answer.

how do I give a div a responsive height

I don't think this is the BEST solution, but it does appear to work. Instead of using the background color, I'm going to just embed an image of the background, position it relatively and then wrap the text in a child element and position it absolute - in the centre.

How to sort an array of objects by multiple fields?

Just another option. Consider to use the following utility function:

/** Performs comparing of two items by specified properties
 * @param  {Array} props for sorting ['name'], ['value', 'city'], ['-date']
 * to set descending order on object property just add '-' at the begining of property
 */
export const compareBy = (...props) => (a, b) => {
  for (let i = 0; i < props.length; i++) {
    const ascValue = props[i].startsWith('-') ? -1 : 1;
    const prop = props[i].startsWith('-') ? props[i].substr(1) : props[i];
    if (a[prop] !== b[prop]) {
      return a[prop] > b[prop] ? ascValue : -ascValue;
    }
  }
  return 0;
};

Example of usage (in your case):

homes.sort(compareBy('city', '-price'));

It should be noted that this function can be even more generalized in order to be able to use nested properties like 'address.city' or 'style.size.width' etc.

DeprecationWarning: Buffer() is deprecated due to security and usability issues when I move my script to another server

var userPasswordString = new Buffer(baseAuth, 'base64').toString('ascii');

Change this line from your code to this -

var userPasswordString = Buffer.from(baseAuth, 'base64').toString('ascii');

or in my case, I gave the encoding in reverse order

var userPasswordString = Buffer.from(baseAuth, 'utf-8').toString('base64');

Angular2 Exception: Can't bind to 'routerLink' since it isn't a known native property

>=RC.5

import the RouterModule See also https://angular.io/guide/router

@NgModule({ 
  imports: [RouterModule],
  ...
})

>=RC.2

app.routes.ts

import { provideRouter, RouterConfig } from '@angular/router';

export const routes: RouterConfig = [
  ...
];

export const APP_ROUTER_PROVIDERS = [provideRouter(routes)];

main.ts

import { bootstrap } from '@angular/platform-browser-dynamic';
import { APP_ROUTER_PROVIDERS } from './app.routes';

bootstrap(AppComponent, [APP_ROUTER_PROVIDERS]);

<=RC.1

Your code is missing

  @Component({
    ...
    directives: [ROUTER_DIRECTIVES],
    ...)}

You can't use directives like routerLink or router-outlet without making them known to your component.

While directive names were changed to be case-sensitive in Angular2, elements still use - in the name like <router-outlet> to be compatible with the web-components spec which require a - in the name of custom elements.

register globally

To make ROUTER_DIRECTIVES globally available, add this provider to bootstrap(...):

provide(PLATFORM_DIRECTIVES, {useValue: [ROUTER_DIRECTIVES], multi: true})

then it's no longer necessary to add ROUTER_DIRECTIVES to each component.

Show current assembly instruction in GDB

You can do

display/i $pc

and every time GDB stops, it will display the disassembly of the next instruction.

GDB-7.0 also supports set disassemble-next-line on, which will disassemble the entire next line, and give you more of the disassembly context.

JPG vs. JPEG image formats

JPG and JPEG stand both for an image format proposed and supported by the Joint Photographic Experts Group. The two terms have the same meaning and are interchangeable.

To read on, check out Difference between JPG and JPEG.

  • The reason for the different file extensions dates back to the early versions of Windows. The original file extension for the Joint Photographic Expert Group File Format was ‘.jpeg’; however in Windows all files required a three letter file extension. So, the file extension was shortened to ‘.jpg’. However, Macintosh was not limited to three letter file extensions, so Mac users used ‘.jpeg’. Eventually, with upgrades Windows also began to accept ‘.jpeg’. However, many users were already used to ‘.jpg’, so both the three letter file extension and the four letter extension began to be commonly used, and still is.

  • Today, the most commonly accepted and used form is the ‘.jpg’, as many users were Windows users. Imaging applications, such as Adobe Photoshop, save all JPEG files with a ".jpg" extension on both Mac and Windows, in an attempt to avoid confusion. The Joint Photographic Expert Group File Format can also be saved with the upper-case ‘.JPEG’ and ‘.JPG’ file extensions, which are less common, but also accepted.

Correct way to create rounded corners in Twitter Bootstrap

As per bootstrap 3.0 documentation. there is no rounded corners class or id for div tag.

you can use circle behavior for image by using

<img class="img-circle"> 

or just use custom border-radius css3 property in css

for only bottom rounded coner use following

border-bottom-left-radius:25%; // i use percentage  u can use pix.
border-bottom-right-radius:25%;// i use percentage  u can use pix.

if you want responsive circular div then try this

referred from Responsive CSS Circles

Why am I getting string does not name a type Error?

You can overcome this error in two simple ways

First way

using namespace std;
include <string>
// then you can use string class the normal way

Second way

// after including the class string in your cpp file as follows
include <string>
/*Now when you are using a string class you have to put **std::** before you write 
string as follows*/
std::string name; // a string declaration

Is SQL syntax case sensitive?

My understanding is that the SQL standard calls for case-insensitivity. I don't believe any databases follow the standard completely, though.

MySQL has a configuration setting as part of its "strict mode" (a grab bag of several settings that make MySQL more standards-compliant) for case sensitive or insensitive table names. Regardless of this setting, column names are still case-insensitive, although I think it affects how the column-names are displayed. I believe this setting is instance-wide, across all databases within the RDBMS instance, although I'm researching today to confirm this (and hoping the answer is no).

I like how Oracle handles this far better. In straight SQL, identifiers like table and column names are case insensitive. However, if for some reason you really desire to get explicit casing, you can enclose the identifier in double-quotes (which are quite different in Oracle SQL from the single-quotes used to enclose string data). So:

SELECT fieldName
FROM tableName;

will query fieldname from tablename, but

SELECT "fieldName"
FROM "tableName";

will query fieldName from tableName.

I'm pretty sure you could even use this mechanism to insert spaces or other non-standard characters into an identifier.

In this situation if for some reason you found explicitly-cased table and column names desirable it was available to you, but it was still something I would highly caution against.

My convention when I used Oracle on a daily basis was that in code I would put all Oracle SQL keywords in uppercase and all identifiers in lowercase. In documentation I would put all table and column names in uppercase. It was very convenient and readable to be able to do this (although sometimes a pain to type so many capitals in code -- I'm sure I could've found an editor feature to help, here).

In my opinion MySQL is particularly bad for differing about this on different platforms. We need to be able to dump databases on Windows and load them into UNIX, and doing so is a disaster if the installer on Windows forgot to put the RDBMS into case-sensitive mode. (To be fair, part of the reason this is a disaster is our coders made the bad decision, long ago, to rely on the case-sensitivity of MySQL on UNIX.) The people who wrote the Windows MySQL installer made it really convenient and Windows-like, and it was great to move toward giving people a checkbox to say "Would you like to turn on strict mode and make MySQL more standards-compliant?" But it is very convenient for MySQL to differ so signficantly from the standard, and then make matters worse by turning around and differing from its own de facto standard on different platforms. I'm sure that on differing Linux distributions this may be further compounded, as packagers for different distros probably have at times incorporated their own preferred MySQL configuration settings.

Here's another SO question that gets into discussing if case-sensitivity is desirable in an RDBMS.

Install gitk on Mac

You can also get gitk with the git from MacPorts.

sudo port install git

How do I pass multiple attributes into an Angular.js attribute directive?

If you "require" 'exampleDirective' from another directive + your logic is in 'exampleDirective's' controller (let's say 'exampleCtrl'):

app.directive('exampleDirective', function () {
    return {
        restrict: 'A',
        scope: false,
        bindToController: {
            myCallback: '&exampleFunction'
        },
        controller: 'exampleCtrl',
        controllerAs: 'vm'
    };
});
app.controller('exampleCtrl', function () {
    var vm = this;
    vm.myCallback();
});

Efficient way to add spaces between characters in a string

s = "BINGO"
print(" ".join(s))

Should do it.

how to use json file in html code

<html>
<head>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"> </script>

<script>

    $(function() {


   var people = [];

   $.getJSON('people.json', function(data) {
       $.each(data.person, function(i, f) {
          var tblRow = "<tr>" + "<td>" + f.firstName + "</td>" +
           "<td>" + f.lastName + "</td>" + "<td>" + f.job + "</td>" + "<td>" + f.roll + "</td>" + "</tr>"
           $(tblRow).appendTo("#userdata tbody");
     });

   });

});
</script>
</head>

<body>

<div class="wrapper">
<div class="profile">
   <table id= "userdata" border="2">
  <thead>
            <th>First Name</th>
            <th>Last Name</th>
            <th>Email Address</th>
            <th>City</th>
        </thead>
      <tbody>

       </tbody>
   </table>

</div>
</div>

</body>
</html>

My JSON file:

{
   "person": [
       {
           "firstName": "Clark",
           "lastName": "Kent",
           "job": "Reporter",
           "roll": 20
       },
       {
           "firstName": "Bruce",
           "lastName": "Wayne",
           "job": "Playboy",
           "roll": 30
       },
       {
           "firstName": "Peter",
           "lastName": "Parker",
           "job": "Photographer",
           "roll": 40
       }
   ]
}

I succeeded in integrating a JSON file to HTML table after working a day on it!!!

How to POST JSON request using Apache HttpClient?

Apache HttpClient doesn't know anything about JSON, so you'll need to construct your JSON separately. To do so, I recommend checking out the simple JSON-java library from json.org. (If "JSON-java" doesn't suit you, json.org has a big list of libraries available in different languages.)

Once you've generated your JSON, you can use something like the code below to POST it

StringRequestEntity requestEntity = new StringRequestEntity(
    JSON_STRING,
    "application/json",
    "UTF-8");

PostMethod postMethod = new PostMethod("http://example.com/action");
postMethod.setRequestEntity(requestEntity);

int statusCode = httpClient.executeMethod(postMethod);

Edit

Note - The above answer, as asked for in the question, applies to Apache HttpClient 3.1. However, to help anyone looking for an implementation against the latest Apache client:

StringEntity requestEntity = new StringEntity(
    JSON_STRING,
    ContentType.APPLICATION_JSON);

HttpPost postMethod = new HttpPost("http://example.com/action");
postMethod.setEntity(requestEntity);

HttpResponse rawResponse = httpclient.execute(postMethod);

Git: How to commit a manually deleted file?

It says right there in the output of git status:

#   (use "git add/rm <file>..." to update what will be committed)

so just do:

git rm <filename>

Extracting time from POSIXct

Here's an update for those looking for a tidyverse method to extract hh:mm::ss.sssss from a POSIXct object. Note that time zone is not included in the output.

library(hms)
as_hms(times)

jQuery - find child with a specific class

Based on your comment, moddify this:

$( '.bgHeaderH2' ).html (); // will return whatever is inside the DIV

to:

$( '.bgHeaderH2', $( this ) ).html (); // will return whatever is inside the DIV

More about selectors: https://api.jquery.com/category/selectors/

How do I put an already-running process under nohup?

This worked for me on Ubuntu linux while in tcshell.

  1. CtrlZ to pause it

  2. bg to run in background

  3. jobs to get its job number

  4. nohup %n where n is the job number

How to find substring inside a string (or how to grep a variable)?

You can use "index" if you only want to find a single character, e.g.:

LIST="server1 server2 server3 server4 server5"
SOURCE="3"
if expr index "$LIST" "$SOURCE"; then
    echo "match"
    exit -1
else
    echo "no match"
fi

Output is:

23
match

Can Windows' built-in ZIP compression be scripted?

There are VBA methods to zip and unzip using the windows built in compression as well, which should give some insight as to how the system operates. You may be able to build these methods into a scripting language of your choice.

The basic principle is that within windows you can treat a zip file as a directory, and copy into and out of it. So to create a new zip file, you simply make a file with the extension .zip that has the right header for an empty zip file. Then you close it, and tell windows you want to copy files into it as though it were another directory.

Unzipping is easier - just treat it as a directory.

In case the web pages are lost again, here are a few of the relevant code snippets:

ZIP

Sub NewZip(sPath)
'Create empty Zip File
'Changed by keepITcool Dec-12-2005
    If Len(Dir(sPath)) > 0 Then Kill sPath
    Open sPath For Output As #1
    Print #1, Chr$(80) & Chr$(75) & Chr$(5) & Chr$(6) & String(18, 0)
    Close #1
End Sub


Function bIsBookOpen(ByRef szBookName As String) As Boolean
' Rob Bovey
    On Error Resume Next
    bIsBookOpen = Not (Application.Workbooks(szBookName) Is Nothing)
End Function


Function Split97(sStr As Variant, sdelim As String) As Variant
'Tom Ogilvy
    Split97 = Evaluate("{""" & _
                       Application.Substitute(sStr, sdelim, """,""") & """}")
End Function

Sub Zip_File_Or_Files()
    Dim strDate As String, DefPath As String, sFName As String
    Dim oApp As Object, iCtr As Long, I As Integer
    Dim FName, vArr, FileNameZip

    DefPath = Application.DefaultFilePath
    If Right(DefPath, 1) <> "\" Then
        DefPath = DefPath & "\"
    End If

    strDate = Format(Now, " dd-mmm-yy h-mm-ss")
    FileNameZip = DefPath & "MyFilesZip " & strDate & ".zip"

    'Browse to the file(s), use the Ctrl key to select more files
    FName = Application.GetOpenFilename(filefilter:="Excel Files (*.xl*), *.xl*", _
                    MultiSelect:=True, Title:="Select the files you want to zip")
    If IsArray(FName) = False Then
        'do nothing
    Else
        'Create empty Zip File
        NewZip (FileNameZip)
        Set oApp = CreateObject("Shell.Application")
        I = 0
        For iCtr = LBound(FName) To UBound(FName)
            vArr = Split97(FName(iCtr), "\")
            sFName = vArr(UBound(vArr))
            If bIsBookOpen(sFName) Then
                MsgBox "You can't zip a file that is open!" & vbLf & _
                       "Please close it and try again: " & FName(iCtr)
            Else
                'Copy the file to the compressed folder
                I = I + 1
                oApp.Namespace(FileNameZip).CopyHere FName(iCtr)

                'Keep script waiting until Compressing is done
                On Error Resume Next
                Do Until oApp.Namespace(FileNameZip).items.Count = I
                    Application.Wait (Now + TimeValue("0:00:01"))
                Loop
                On Error GoTo 0
            End If
        Next iCtr

        MsgBox "You find the zipfile here: " & FileNameZip
    End If
End Sub

UNZIP

Sub Unzip1()
    Dim FSO As Object
    Dim oApp As Object
    Dim Fname As Variant
    Dim FileNameFolder As Variant
    Dim DefPath As String
    Dim strDate As String

    Fname = Application.GetOpenFilename(filefilter:="Zip Files (*.zip), *.zip", _
                                        MultiSelect:=False)
    If Fname = False Then
        'Do nothing
    Else
        'Root folder for the new folder.
        'You can also use DefPath = "C:\Users\Ron\test\"
        DefPath = Application.DefaultFilePath
        If Right(DefPath, 1) <> "\" Then
            DefPath = DefPath & "\"
        End If

        'Create the folder name
        strDate = Format(Now, " dd-mm-yy h-mm-ss")
        FileNameFolder = DefPath & "MyUnzipFolder " & strDate & "\"

        'Make the normal folder in DefPath
        MkDir FileNameFolder

        'Extract the files into the newly created folder
        Set oApp = CreateObject("Shell.Application")

        oApp.Namespace(FileNameFolder).CopyHere oApp.Namespace(Fname).items

        'If you want to extract only one file you can use this:
        'oApp.Namespace(FileNameFolder).CopyHere _
         'oApp.Namespace(Fname).items.Item("test.txt")

        MsgBox "You find the files here: " & FileNameFolder

        On Error Resume Next
        Set FSO = CreateObject("scripting.filesystemobject")
        FSO.deletefolder Environ("Temp") & "\Temporary Directory*", True
    End If
End Sub

How to respond to clicks on a checkbox in an AngularJS directive?

Liviu's answer was extremely helpful for me. Hope this is not bad form but i made a fiddle that may help someone else out in the future.

Two important pieces that are needed are:

    $scope.entities = [{
    "title": "foo",
    "id": 1
}, {
    "title": "bar",
    "id": 2
}, {
    "title": "baz",
    "id": 3
}];
$scope.selected = [];

How to fill the whole canvas with specific color?

We don't need to access the canvas context.

Implementing hednek in pure JS you would get canvas.setAttribute('style', 'background-color:#00F8'). But my preferred method requires converting the kabab-case to camelCase.

canvas.style.backgroundColor = '#00F8'

How can I create basic timestamps or dates? (Python 3.4)

Ultimately you want to review the datetime documentation and become familiar with the formatting variables, but here are some examples to get you started:

import datetime

print('Timestamp: {:%Y-%m-%d %H:%M:%S}'.format(datetime.datetime.now()))
print('Timestamp: {:%Y-%b-%d %H:%M:%S}'.format(datetime.datetime.now()))
print('Date now: %s' % datetime.datetime.now())
print('Date today: %s' % datetime.date.today())

today = datetime.date.today()
print("Today's date is {:%b, %d %Y}".format(today))

schedule = '{:%b, %d %Y}'.format(today) + ' - 6 PM to 10 PM Pacific'
schedule2 = '{:%B, %d %Y}'.format(today) + ' - 1 PM to 6 PM Central'
print('Maintenance: %s' % schedule)
print('Maintenance: %s' % schedule2)

The output:

Timestamp: 2014-10-18 21:31:12

Timestamp: 2014-Oct-18 21:31:12

Date now: 2014-10-18 21:31:12.318340

Date today: 2014-10-18

Today's date is Oct, 18 2014

Maintenance: Oct, 18 2014 - 6 PM to 10 PM Pacific

Maintenance: October, 18 2014 - 1 PM to 6 PM Central

Reference link: https://docs.python.org/3.4/library/datetime.html#strftime-strptime-behavior

How to remove a Gitlab project?

  • 1.Gitlab Home Page
  • 2.Select your projects button under Projects Menus
  • 3.Click your desired project
  • 4.Select Settings (from left sidebar)
  • 5.Click Advanced settings Expand the Advanced settings this will be middle of the page
  • 6.Click Remove
  • 7.Project In the Modal write your project name

Hope you can Successfully remove your project. Happy Coding :)

Singleton in Android

You are copying singleton's customVar into a singletonVar variable and changing that variable does not affect the original value in singleton.

// This does not update singleton variable
// It just assigns value of your local variable
Log.d("Test",singletonVar);
singletonVar="World";
Log.d("Test",singletonVar);

// This actually assigns value of variable in singleton
Singleton.customVar = singletonVar;

SQL- Ignore case while searching for a string

See this similar question and answer to searching with case insensitivity - SQL server ignore case in a where expression

Try using something like:

SELECT DISTINCT COL_NAME 
FROM myTable 
WHERE COL_NAME COLLATE SQL_Latin1_General_CP1_CI_AS LIKE '%priceorder%'

Merging two arrayLists into a new arrayList, with no duplicates and in order, in Java

Firstly remove duplicates:

arrayList1.removeAll(arrayList2);

Then merge two arrayList:

arrayList1.addAll(arrayList2);

Lastly, sort your arrayList if you wish:

collections.sort(arrayList1);

In case you don't want to make any changes on the existing list, first create their backup lists:

arrayList1Backup = new ArrayList(arrayList1);

Extract time from moment js object

If you read the docs (http://momentjs.com/docs/#/displaying/) you can find this format:

moment("2015-01-16T12:00:00").format("hh:mm:ss a")

See JS Fiddle http://jsfiddle.net/Bjolja/6mn32xhu/

How to change the font color in the textbox in C#?

Assuming WinForms, the ForeColor property allows to change all the text in the TextBox (not just what you're about to add):

TextBox.ForeColor = Color.Red;

To only change the color of certain words, look at RichTextBox.

Java naming convention for static final variables

That's still a constant. See the JLS for more information regarding the naming convention for constants. But in reality, it's all a matter of preference.


The names of constants in interface types should be, and final variables of class types may conventionally be, a sequence of one or more words, acronyms, or abbreviations, all uppercase, with components separated by underscore "_" characters. Constant names should be descriptive and not unnecessarily abbreviated. Conventionally they may be any appropriate part of speech. Examples of names for constants include MIN_VALUE, MAX_VALUE, MIN_RADIX, and MAX_RADIX of the class Character.

A group of constants that represent alternative values of a set, or, less frequently, masking bits in an integer value, are sometimes usefully specified with a common acronym as a name prefix, as in:

interface ProcessStates {
  int PS_RUNNING = 0;
  int PS_SUSPENDED = 1;
}

Obscuring involving constant names is rare:

  • Constant names normally have no lowercase letters, so they will not normally obscure names of packages or types, nor will they normally shadow fields, whose names typically contain at least one lowercase letter.
  • Constant names cannot obscure method names, because they are distinguished syntactically.

How can I tell gcc not to inline a function?

GCC has a switch called

-fno-inline-small-functions

So use that when invoking gcc. But the side effect is that all other small functions are also non-inlined.

Generating a UUID in Postgres for Insert statement?

Without extensions (cheat)

SELECT uuid_in(md5(random()::text || clock_timestamp()::text)::cstring);

output>> c2d29867-3d0b-d497-9191-18a9d8ee7830

(works at least in 8.4)

  • Thanks to @Erwin Brandstetter for clock_timestamp() explanation.

If you need a valid v4 UUID

SELECT uuid_in(overlay(overlay(md5(random()::text || ':' || clock_timestamp()::text) placing '4' from 13) placing to_hex(floor(random()*(11-8+1) + 8)::int)::text from 17)::cstring);

enter image description here * Thanks to @Denis Stafichuk @Karsten and @autronix


Also, in modern Postgres, you can simply cast:

SELECT md5(random()::text || clock_timestamp()::text)::uuid

How to redirect back to form with input - Laravel 5

I handle validation exceptions in Laravel 5.3 like this. If you use Laravel Collective it will automatically display errors next to inputs and if you use laracasts/flash it will also show first validation error as a notice.


Handler.php render:

public function render($request, Exception $e)
{
    if ($e instanceof \Illuminate\Validation\ValidationException) {
        return $this->handleValidationException($request, $e);
    }

    (..)
}

And the function:

protected function handleValidationException($request, $e)
    {
        $errors = @$e->validator->errors()->toArray();
        $message = null;
        if (count($errors)) {
            $firstKey = array_keys($errors)[0];
            $message = @$e->validator->errors()->get($firstKey)[0];
            if (strlen($message) == 0) {
                $message = "An error has occurred when trying to register";
            }
        }

        if ($message == null) {
            $message = "An unknown error has occured";
        }

        \Flash::error($message);

        return \Illuminate\Support\Facades\Redirect::back()->withErrors($e->validator)->withInput();
    }

How can I tell which button was clicked in a PHP form submit?

Are you asking in php or javascript.

If it is in php, give the name of that and use the post or get method, after that you can use the option of isset or that particular button name is checked to that value.

If it is in js, use getElementById for that

How to use youtube-dl from a python program?

It's not difficult and actually documented:

import youtube_dl

ydl = youtube_dl.YoutubeDL({'outtmpl': '%(id)s.%(ext)s'})

with ydl:
    result = ydl.extract_info(
        'http://www.youtube.com/watch?v=BaW_jenozKc',
        download=False # We just want to extract the info
    )

if 'entries' in result:
    # Can be a playlist or a list of videos
    video = result['entries'][0]
else:
    # Just a video
    video = result

print(video)
video_url = video['url']
print(video_url)

Sending and receiving data over a network using TcpClient

First of all, TCP does not guarantee that everything that you send will be received with the same read at the other end. It only guarantees that all bytes that you send will arrive and in the correct order.

Therefore, you will need to keep building up a buffer when reading from the stream. You will also have to know how large each message is.

The simplest ever is to use a non-typeable ASCII character to mark the end of the packet and look for it in the received data.

How to add a new row to datagridview programmatically

yourDGV.Rows.Add(column1,column2...columnx); //add a row to a dataGridview
yourDGV.Rows[rowindex].Cells[Cell/Columnindex].value = yourvalue; //edit the value

you can also create a new row and then add it to the DataGridView like this:

DataGridViewRow row = new DataGridViewRow();
row.Cells[Cell/Columnindex].Value = yourvalue;
yourDGV.Rows.Add(row);

How to set .net Framework 4.5 version in IIS 7 application pool

Go to "Run" and execute this:

%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe -ir

NOTE: run as administrator.

How can I calculate the difference between two ArrayLists?

In Java 8 with streams, it's pretty simple actually. EDIT: Can be efficient without streams, see lower.

List<String> listA = Arrays.asList("2009-05-18","2009-05-19","2009-05-21");
List<String> listB = Arrays.asList("2009-05-18","2009-05-18","2009-05-19","2009-05-19",
                                   "2009-05-20","2009-05-21","2009-05-21","2009-05-22");

List<String> result = listB.stream()
                           .filter(not(new HashSet<>(listA)::contains))
                           .collect(Collectors.toList());

Note that the hash set is only created once: The method reference is tied to its contains method. Doing the same with lambda would require having the set in a variable. Making a variable is not a bad idea, especially if you find it unsightly or harder to understand.

You can't easily negate the predicate without something like this utility method (or explicit cast), as you can't call the negate method reference directly (type inference is needed first).

private static <T> Predicate<T> not(Predicate<T> predicate) {
    return predicate.negate();
}

If streams had a filterOut method or something, it would look nicer.


Also, @Holger gave me an idea. ArrayList has its removeAll method optimized for multiple removals, it only rearranges its elements once. However, it uses the contains method provided by given collection, so we need to optimize that part if listA is anything but tiny.

With listA and listB declared previously, this solution doesn't need Java 8 and it's very efficient.

List<String> result = new ArrayList(listB);
result.removeAll(new HashSet<>(listA));

Summing elements in a list

You can use map function and pythons inbuilt sum() function. It simplifies the solution. And reduces the complexity.
a=map(int,raw_input().split())
sum(a)
Done!

Why doesn't the height of a container element increase if it contains floated elements?

you can use overflow property to the container div if you don't have any div to show over the container eg:

<div class="cointainer">
    <div class="one">Content One</div>
    <div class="two">Content Two</div>
</div>

Here is the following css:

.container{
    width:100%;/* As per your requirment */
    height:auto;
    float:left;
    overflow:hidden;
}
.one{
    width:200px;/* As per your requirment */
    height:auto;
    float:left;
}

.two{
    width:200px;/* As per your requirment */
    height:auto;
    float:left;
}

-----------------------OR------------------------------

    <div class="cointainer">
        <div class="one">Content One</div>
        <div class="two">Content Two</div>
        <div class="clearfix"></div>
    </div>

Here is the following css:

    .container{
        width:100%;/* As per your requirment */
        height:auto;
        float:left;
        overflow:hidden;
    }
    .one{
        width:200px;/* As per your requirment */
        height:auto;
        float:left;
    }

    .two{
        width:200px;/* As per your requirment */
        height:auto;
        float:left;
    }
    .clearfix:before,
    .clearfix:after{
        display: table;
        content: " ";
    }
    .clearfix:after{
        clear: both;
    }

How to remove all non-alpha numeric characters from a string in MySQL?

So far, the only alternative approach less complicated than the other answers here is to determine the full set of special characters of the column, i.e. all the special characters that are in use in that column at the moment, and then do a sequential replace of all those characters, e.g.

update pages set slug = lower(replace(replace(replace(replace(name, ' ', ''), '-', ''), '.', ''), '&', '')); # replacing just space, -, ., & only

.

This is only advisable on a known set of data, otherwise it's trivial for some special characters to slip past with a blacklist approach instead of a whitelist approach.

Obviously, the simplest way is to pre-validate the data outside of sql due to the lack of robust built-in whitelisting (e.g. via a regex replace).

Java Could not reserve enough space for object heap error

this is what worked for me (yes I was having the same problem) were is says something like java -Xmx3G -Xms3G put java -Xmx1024M so the run.bat should look like java -Xmx1024M -jar craftbukkit.jar -o false PAUSE

@ViewChild in *ngIf

My goal was to avoid any hacky methods that assume something (e.g. setTimeout) and I ended up implementing the accepted solution with a bit of RxJS flavour on top:

  private ngUnsubscribe = new Subject();
  private tabSetInitialized = new Subject();
  public tabSet: TabsetComponent;
  @ViewChild('tabSet') set setTabSet(tabset: TabsetComponent) {
    if (!!tabSet) {
      this.tabSet = tabSet;
      this.tabSetInitialized.next();
    }
  }

  ngOnInit() {
    combineLatest(
      this.route.queryParams,
      this.tabSetInitialized
    ).pipe(
      takeUntil(this.ngUnsubscribe)
    ).subscribe(([queryParams, isTabSetInitialized]) => {
      let tab = [undefined, 'translate', 'versions'].indexOf(queryParams['view']);
      this.tabSet.tabs[tab > -1 ? tab : 0].active = true;
    });
  }

My scenario: I wanted to fire an action on a @ViewChild element depending on the router queryParams. Due to a wrapping *ngIf being false until the HTTP request returns the data, the initialization of the @ViewChild element happens with a delay.

How does it work: combineLatest emits a value for the first time only when each of the provided Observables emit the first value since the moment combineLatest was subscribed to. My Subject tabSetInitialized emits a value when the @ViewChild element is being set. Therewith, I delay the execution of the code under subscribe until the *ngIf turns positive and the @ViewChild gets initialized.

Of course don't forget to unsubscribe on ngOnDestroy, I do it using the ngUnsubscribe Subject:

  ngOnDestroy() {
    this.ngUnsubscribe.next();
    this.ngUnsubscribe.complete();
  }

oracle diff: how to compare two tables?

Try:

select distinct T1.id
  from TABLE1 T1
 where not exists (select distinct T2.id
                     from TABLE2 T2
                    where T2.id = T1.id)

With sql oracle 11g+

Insert multiple values using INSERT INTO (SQL Server 2005)

In SQL Server 2008,2012,2014 you can insert multiple rows using a single SQL INSERT statement.

 INSERT INTO TableName ( Column1, Column2 ) VALUES
    ( Value1, Value2 ), ( Value1, Value2 )

Another way

INSERT INTO TableName (Column1, Column2 )
SELECT Value1 ,Value2
UNION ALL
SELECT Value1 ,Value2
UNION ALL
SELECT Value1 ,Value2
UNION ALL
SELECT Value1 ,Value2
UNION ALL
SELECT Value1 ,Value2

Nginx upstream prematurely closed connection while reading response header from upstream, for large requests

I had the same error for quite a while, and here what fixed it for me.

I simply declared in service that i use what follows:

Description= Your node service description
After=network.target

[Service]
Type=forking
PIDFile=/tmp/node_pid_name.pid
Restart=on-failure
KillSignal=SIGQUIT
WorkingDirectory=/path/to/node/app/root/directory
ExecStart=/path/to/node /path/to/server.js

[Install]
WantedBy=multi-user.target

What should catch your attention here is "After=network.target". I spent days and days looking for fixes on nginx side, while the problem was just that. To be sure, stop running the node service you have, launch the ExecStart command directly and try to reproduce the bug. If it doesn't pop, it just means that your service has a problem. At least this is how i found my answer.

For everybody else, good luck!

Hour from DateTime? in 24 hours format

date.ToString("HH:mm:ss"); // for 24hr format
date.ToString("hh:mm:ss"); // for 12hr format, it shows AM/PM

Refer this link for other Formatters in DateTime.

What is the difference between absolute and relative xpaths? Which is preferred in Selenium automation testing?

Absolute Xpath: It uses Complete path from the Root Element to the desire element.

Relative Xpath: You can simply start by referencing the element you want and go from there.

Relative Xpaths are always preferred as they are not the complete paths from the root element. (//html//body). Because in future, if any webelement is added/removed, then the absolute Xpath changes. So Always use Relative Xpaths in your Automation.

Below are Some Links which you can Refer for more Information on them.

With ng-bind-html-unsafe removed, how do I inject HTML?

  1. You need to make sure that sanitize.js is loaded. For example, load it from https://ajax.googleapis.com/ajax/libs/angularjs/[LAST_VERSION]/angular-sanitize.min.js
  2. you need to include ngSanitize module on your app eg: var app = angular.module('myApp', ['ngSanitize']);
  3. you just need to bind with ng-bind-html the original html content. No need to do anything else in your controller. The parsing and conversion is automatically done by the ngBindHtml directive. (Read the How does it work section on this: $sce). So, in your case <div ng-bind-html="preview_data.preview.embed.html"></div> would do the work.

Remove last character from string. Swift language

Use the function removeAtIndex(i: String.Index) -> Character:

var s = "abc"    
s.removeAtIndex(s.endIndex.predecessor())  // "ab"

How to change checkbox's border style in CSS?

Here is a pure CSS (no images) cross-browser solution based on Martin's Custom Checkboxes and Radio Buttons with CSS3 LINK: http://martinivanov.net/2012/12/21/imageless-custom-checkboxes-and-radio-buttons-with-css3-revisited/

Here is a jsFiddle: http://jsfiddle.net/DJRavine/od26wL6n/

I have tested this on the following browsers:

  • FireFox (41.0.2) (42)
  • Google Chrome (46.0.2490.80 m)
  • Opera (33.0.1990.43)
  • Internet Explorer (11.0.10240.16431 [Update Versions: 11.0.22])
  • Microsoft Edge (20.10240.16384.0)
  • Safari Mobile iPhone iOS9 (601.1.46)

_x000D_
_x000D_
label,_x000D_
input[type="radio"] + span,_x000D_
input[type="radio"] + span::before,_x000D_
label,_x000D_
input[type="checkbox"] + span,_x000D_
input[type="checkbox"] + span::before_x000D_
{_x000D_
    display: inline-block;_x000D_
    vertical-align: middle;_x000D_
}_x000D_
 _x000D_
label *,_x000D_
label *_x000D_
{_x000D_
    cursor: pointer;_x000D_
}_x000D_
 _x000D_
input[type="radio"],_x000D_
input[type="checkbox"]_x000D_
{_x000D_
    opacity: 0;_x000D_
    position: absolute;_x000D_
}_x000D_
 _x000D_
input[type="radio"] + span,_x000D_
input[type="checkbox"] + span_x000D_
{_x000D_
    font: normal 11px/14px Arial, Sans-serif;_x000D_
    color: #333;_x000D_
}_x000D_
 _x000D_
label:hover span::before,_x000D_
label:hover span::before_x000D_
{_x000D_
    -moz-box-shadow: 0 0 2px #ccc;_x000D_
    -webkit-box-shadow: 0 0 2px #ccc;_x000D_
    box-shadow: 0 0 2px #ccc;_x000D_
}_x000D_
 _x000D_
label:hover span,_x000D_
label:hover span_x000D_
{_x000D_
    color: #000;_x000D_
}_x000D_
 _x000D_
input[type="radio"] + span::before,_x000D_
input[type="checkbox"] + span::before_x000D_
{_x000D_
    content: "";_x000D_
    width: 12px;_x000D_
    height: 12px;_x000D_
    margin: 0 4px 0 0;_x000D_
    border: solid 1px #a8a8a8;_x000D_
    line-height: 14px;_x000D_
    text-align: center;_x000D_
     _x000D_
    -moz-border-radius: 100%;_x000D_
    -webkit-border-radius: 100%;_x000D_
    border-radius: 100%;_x000D_
     _x000D_
    background: #f6f6f6;_x000D_
    background: -moz-radial-gradient(#f6f6f6, #dfdfdf);_x000D_
    background: -webkit-radial-gradient(#f6f6f6, #dfdfdf);_x000D_
    background: -ms-radial-gradient(#f6f6f6, #dfdfdf);_x000D_
    background: -o-radial-gradient(#f6f6f6, #dfdfdf);_x000D_
    background: radial-gradient(#f6f6f6, #dfdfdf);_x000D_
}_x000D_
 _x000D_
input[type="radio"]:checked + span::before,_x000D_
input[type="checkbox"]:checked + span::before_x000D_
{_x000D_
    color: #666;_x000D_
}_x000D_
 _x000D_
input[type="radio"]:disabled + span,_x000D_
input[type="checkbox"]:disabled + span_x000D_
{_x000D_
    cursor: default;_x000D_
     _x000D_
    -moz-opacity: .4;_x000D_
    -webkit-opacity: .4;_x000D_
    opacity: .4;_x000D_
}_x000D_
 _x000D_
input[type="checkbox"] + span::before_x000D_
{_x000D_
    -moz-border-radius: 2px;_x000D_
    -webkit-border-radius: 2px;_x000D_
    border-radius: 2px;_x000D_
}_x000D_
 _x000D_
input[type="radio"]:checked + span::before_x000D_
{_x000D_
    content: "\2022";_x000D_
    font-size: 30px;_x000D_
    margin-top: -1px;_x000D_
}_x000D_
 _x000D_
input[type="checkbox"]:checked + span::before_x000D_
{_x000D_
    content: "\2714";_x000D_
    font-size: 12px;_x000D_
}_x000D_
_x000D_
_x000D_
_x000D_
input[class="blue"] + span::before_x000D_
{_x000D_
    border: solid 1px blue;_x000D_
    background: #B2DBFF;_x000D_
    background: -moz-radial-gradient(#B2DBFF, #dfdfdf);_x000D_
    background: -webkit-radial-gradient(#B2DBFF, #dfdfdf);_x000D_
    background: -ms-radial-gradient(#B2DBFF, #dfdfdf);_x000D_
    background: -o-radial-gradient(#B2DBFF, #dfdfdf);_x000D_
    background: radial-gradient(#B2DBFF, #dfdfdf);_x000D_
}_x000D_
input[class="blue"]:checked + span::before_x000D_
{_x000D_
    color: darkblue;_x000D_
}_x000D_
_x000D_
_x000D_
_x000D_
input[class="red"] + span::before_x000D_
{_x000D_
    border: solid 1px red;_x000D_
    background: #FF9593;_x000D_
    background: -moz-radial-gradient(#FF9593, #dfdfdf);_x000D_
    background: -webkit-radial-gradient(#FF9593, #dfdfdf);_x000D_
    background: -ms-radial-gradient(#FF9593, #dfdfdf);_x000D_
    background: -o-radial-gradient(#FF9593, #dfdfdf);_x000D_
    background: radial-gradient(#FF9593, #dfdfdf);_x000D_
}_x000D_
input[class="red"]:checked + span::before_x000D_
{_x000D_
    color: darkred;_x000D_
}
_x000D_
 <label><input type="radio" checked="checked" name="radios-01" /><span>checked radio button</span></label>_x000D_
 <label><input type="radio" name="radios-01" /><span>unchecked radio button</span></label>_x000D_
 <label><input type="radio" name="radios-01" disabled="disabled" /><span>disabled radio button</span></label>_x000D_
_x000D_
<br/>_x000D_
_x000D_
 <label><input type="radio" checked="checked" name="radios-02"  class="blue" /><span>checked radio button</span></label>_x000D_
 <label><input type="radio" name="radios-02" class="blue" /><span>unchecked radio button</span></label>_x000D_
 <label><input type="radio" name="radios-02" disabled="disabled" class="blue" /><span>disabled radio button</span></label>_x000D_
_x000D_
<br/>_x000D_
_x000D_
 <label><input type="radio" checked="checked" name="radios-03"  class="red" /><span>checked radio button</span></label>_x000D_
 <label><input type="radio" name="radios-03" class="red" /><span>unchecked radio button</span></label>_x000D_
 <label><input type="radio" name="radios-03" disabled="disabled" class="red" /><span>disabled radio button</span></label>_x000D_
_x000D_
<br/>_x000D_
 _x000D_
<label><input type="checkbox" checked="checked" name="checkbox-01" /><span>selected checkbox</span></label>_x000D_
<label><input type="checkbox" name="checkbox-02" /><span>unselected checkbox</span></label>_x000D_
<label><input type="checkbox" name="checkbox-03" disabled="disabled" /><span>disabled checkbox</span></label>_x000D_
_x000D_
<br/>_x000D_
 _x000D_
<label><input type="checkbox" checked="checked" name="checkbox-01" class="blue" /><span>selected checkbox</span></label>_x000D_
<label><input type="checkbox" name="checkbox-02" class="blue" /><span>unselected checkbox</span></label>_x000D_
<label><input type="checkbox" name="checkbox-03" disabled="disabled" class="blue" /><span>disabled checkbox</span></label>_x000D_
_x000D_
<br/>_x000D_
 _x000D_
<label><input type="checkbox" checked="checked" name="checkbox-01" class="red" /><span>selected checkbox</span></label>_x000D_
<label><input type="checkbox" name="checkbox-02" class="red" /><span>unselected checkbox</span></label>_x000D_
<label><input type="checkbox" name="checkbox-03" disabled="disabled" class="red" /><span>disabled checkbox</span></label>
_x000D_
_x000D_
_x000D_

How do you round a floating point number in Perl?

You can either use a module like Math::Round:

use Math::Round;
my $rounded = round( $float );

Or you can do it the crude way:

my $rounded = sprintf "%.0f", $float;

How to execute a query in ms-access in VBA code?

How about something like this...

Dim rs As RecordSet
Set rs = Currentdb.OpenRecordSet("SELECT PictureLocation, ID FROM MyAccessTable;")

Do While Not rs.EOF
   Debug.Print rs("PictureLocation") & " - " & rs("ID")
   rs.MoveNext
Loop

Numpy: Creating a complex array from 2 real ones?

I am python novice so this may not be the most efficient method but, if I understand the intent of the question correctly, steps listed below worked for me.

>>> import numpy as np
>>> Data = np.random.random((100, 100, 1000, 2))
>>> result = np.empty(Data.shape[:-1], dtype=complex)
>>> result.real = Data[...,0]; result.imag = Data[...,1]
>>> print Data[0,0,0,0], Data[0,0,0,1], result[0,0,0]
0.0782889873474 0.156087854837 (0.0782889873474+0.156087854837j)

How to play an android notification sound

If anyone's still looking for a solution to this, I found an answer at How to play ringtone/alarm sound in Android

try {
    Uri notification = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    Ringtone r = RingtoneManager.getRingtone(getApplicationContext(), notification);
    r.play();
} catch (Exception e) {
    e.printStackTrace();
}

You can change TYPE_NOTIFICATION to TYPE_ALARM, but you'll want to keep track of your Ringtone r in order to stop playing it... say, when the user clicks a button or something.

WPF - add static items to a combo box

You can also add items in code:

cboWhatever.Items.Add("SomeItem");

Also, to add something where you control display/value, (almost categorically needed in my experience) you can do so. I found a good stackoverflow reference here:

Key Value Pair Combobox in WPF

Sum-up code would be something like this:

ComboBox cboSomething = new ComboBox();
cboSomething.DisplayMemberPath = "Key";
cboSomething.SelectedValuePath = "Value";
cboSomething.Items.Add(new KeyValuePair<string, string>("Something", "WhyNot"));
cboSomething.Items.Add(new KeyValuePair<string, string>("Deus", "Why"));
cboSomething.Items.Add(new KeyValuePair<string, string>("Flirptidee", "Stuff"));
cboSomething.Items.Add(new KeyValuePair<string, string>("Fernum", "Blictor"));

Tomcat 7 "SEVERE: A child container failed during start"

I solved a similar problem by updating the web.xml declaration to Servlet 4.0 specification as follows (I use Tomcat 9) :

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                          http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
      version="4.0"
      metadata-complete="true">
      <!-- ... (your content here) ... -->
</web-app>

You can check which servlet version Tomcat supports by refering to the chart on Tomcat's which version page.

How to deploy a React App on Apache web server

As well described in React's official docs, If you use routers that use the HTML5 pushState history API under the hood, you just need to below content to .htaccess file in public directory of your react-app.

Options -MultiViews
    RewriteEngine On
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ index.html [QSA,L]

And if using relative path update the package.json like this:

"homepage": ".",

Note: If you are using react-router@^4, you can root <Link> using the basename prop on any <Router>.

import React from 'react';
import BrowserRouter as Router from 'react-router-dom';
...
<Router basename="/calendar"/>
<Link to="/today"/>

Can you "compile" PHP code and upload a binary-ish file, which will just be run by the byte code interpreter?

The short answer is "no".

The current implementation of PHP is that of an interpreted language. You can argue the theoretical aspects of the fact that any language can technically be interpreted or compiled, but as it stands, the current implementations are such that PHP code requires an interpreter to run, and the interpreter manages the executing environment.

To answer your question about uploading pre-compiled PHP bytecode, it's probably possible, but you'd have to implement a way for the PHP interpreter to read in such a file and work with it. With existing opcode caches out there already, it doesn't seem like a task that would reap much reward.

Set Focus After Last Character in Text Box

You should code like this.

var num = $('#Number').val();        
$('#Number').focus().val('').val(num);    

How can I find out the current route in Rails?

To find out URI:

current_uri = request.env['PATH_INFO']
# If you are browsing http://example.com/my/test/path, 
# then above line will yield current_uri as "/my/test/path"

To find out the route i.e. controller, action and params:

path = ActionController::Routing::Routes.recognize_path "/your/path/here/"

# ...or newer Rails versions:
#
path = Rails.application.routes.recognize_path('/your/path/here')

controller = path[:controller]
action = path[:action]
# You will most certainly know that params are available in 'params' hash

How to Clone Objects

a and b are just two references to the same Person object. They both essentially hold the address of the Person.

There is a ICloneable interface, though relatively few classes support it. With this, you would write:

Person b = a.Clone();

Then, b would be an entirely separate Person.

You could also implement a copy constructor:

public Person(Person src)
{
  // ... 
}

There is no built-in way to copy all the fields. You can do it through reflection, but there would be a performance penalty.

Combining two sorted lists in Python

import random

    n=int(input("Enter size of table 1")); #size of list 1
    m=int(input("Enter size of table 2")); # size of list 2
    tb1=[random.randrange(1,101,1) for _ in range(n)] # filling the list with random
    tb2=[random.randrange(1,101,1) for _ in range(m)] # numbers between 1 and 100
    tb1.sort(); #sort the list 1 
    tb2.sort(); # sort the list 2
    fus=[]; # creat an empty list
    print(tb1); # print the list 1
    print('------------------------------------');
    print(tb2); # print the list 2
    print('------------------------------------');
    i=0;j=0;  # varialbles to cross the list
    while(i<n and j<m):
        if(tb1[i]<tb2[j]):
            fus.append(tb1[i]); 
            i+=1;
        else:
            fus.append(tb2[j]);
            j+=1;

    if(i<n):
        fus+=tb1[i:n];
    if(j<m):
        fus+=tb2[j:m];

    print(fus);

  # this code is used to merge two sorted lists in one sorted list (FUS) without
  #sorting the (FUS)

Counter exit code 139 when running, but gdb make it through

this error is also caused by null pointer reference. if you are using a pointer who is not initialized then it causes this error.

to check either a pointer is initialized or not you can try something like

Class *pointer = new Class();
if(pointer!=nullptr){
    pointer->myFunction();
}

Best data type for storing currency values in a MySQL database

Something like Decimal(19,4) usually works pretty well in most cases. You can adjust the scale and precision to fit the needs of the numbers you need to store. Even in SQL Server, I tend not to use "money" as it's non-standard.

How do I use Ruby for shell scripting?

When you want to write more complex ruby scripts, these tools may help:

For example:

  • thor(a scripting framework)

  • gli(git like interface)

  • methadone(for creating simple tools)

They give you a quick start to write your own scripts, especially 'command line app'.

Callback when DOM is loaded in react.js

You can watch your container element using the useRef hook. Note that you need to watch the ref's current value specifically, otherwise it won't work.

Example:

  const containerRef = useRef();
  const { current } = containerRef;

  useEffect(setLinksData, [current]);

return (
    <div ref={containerRef}>
      // your child elements...
    </div>
)

Meaning of Choreographer messages in Logcat

In my case I have these messages when I show the sherlock action bar inderterminate progressbar. Since its not my library, I decided to hide the Choreographer outputs.

You can hide the Choreographer outputs onto the Logcat view, using this filter expression :

tag:^((?!Choreographer).*)$

I used a regex explained elsewhere : Regular expression to match a line that doesn't contain a word?

iOS 6 apps - how to deal with iPhone 5 screen size?

No.

if ([[UIScreen mainScreen] bounds].size.height > 960)

on iPhone 5 is wrong

if ([[UIScreen mainScreen] bounds].size.height == 568)

Can I change the Android startActivity() transition animation?

See themes on android: http://developer.android.com/guide/topics/ui/themes.html.

Under themes.xml there should be android:windowAnimationStyle where you can see the declaration of the style in styles.xml.

Example implementation:

<style name="AppTheme" parent="...">

    ...

    <item name="android:windowAnimationStyle">@style/WindowAnimationStyle</item>

</style>

<style name="WindowAnimationStyle">
    <item name="android:windowEnterAnimation">@android:anim/fade_in</item>
    <item name="android:windowExitAnimation">@android:anim/fade_out</item>
</style>

What is Python used for?

Python is a dynamic, strongly typed, object oriented, multipurpose programming language, designed to be quick (to learn, to use, and to understand), and to enforce a clean and uniform syntax.

  1. Python is dynamically typed: it means that you don't declare a type (e.g. 'integer') for a variable name, and then assign something of that type (and only that type). Instead, you have variable names, and you bind them to entities whose type stays with the entity itself. a = 5 makes the variable name a to refer to the integer 5. Later, a = "hello" makes the variable name a to refer to a string containing "hello". Static typed languages would have you declare int a and then a = 5, but assigning a = "hello" would have been a compile time error. On one hand, this makes everything more unpredictable (you don't know what a refers to). On the other hand, it makes very easy to achieve some results a static typed languages makes very difficult.
  2. Python is strongly typed. It means that if a = "5" (the string whose value is '5') will remain a string, and never coerced to a number if the context requires so. Every type conversion in python must be done explicitly. This is different from, for example, Perl or Javascript, where you have weak typing, and can write things like "hello" + 5 to get "hello5".
  3. Python is object oriented, with class-based inheritance. Everything is an object (including classes, functions, modules, etc), in the sense that they can be passed around as arguments, have methods and attributes, and so on.
  4. Python is multipurpose: it is not specialised to a specific target of users (like R for statistics, or PHP for web programming). It is extended through modules and libraries, that hook very easily into the C programming language.
  5. Python enforces correct indentation of the code by making the indentation part of the syntax. There are no control braces in Python. Blocks of code are identified by the level of indentation. Although a big turn off for many programmers not used to this, it is precious as it gives a very uniform style and results in code that is visually pleasant to read.
  6. The code is compiled into byte code and then executed in a virtual machine. This means that precompiled code is portable between platforms.

Python can be used for any programming task, from GUI programming to web programming with everything else in between. It's quite efficient, as much of its activity is done at the C level. Python is just a layer on top of C. There are libraries for everything you can think of: game programming and openGL, GUI interfaces, web frameworks, semantic web, scientific computing...

Nested rows with bootstrap grid system?

Adding to what @KyleMit said, consider using:

  • col-md-* classes for the larger outer columns
  • col-xs-* classes for the smaller inner columns

This will be useful when you view the page on different screen sizes.

On a small screen, the wrapping of larger outer columns will then happen while maintaining the smaller inner columns, if possible

What are unit tests, integration tests, smoke tests, and regression tests?

REGRESSION TESTING-

"A regression test re-runs previous tests against the changed software to ensure that the changes made in the current software do not affect the functionality of the existing software."

How do I set default terminal to terminator?

Copy-paste the following into your current terminal:

gsettings set org.gnome.desktop.default-applications.terminal exec /usr/bin/terminator
gsettings set org.gnome.desktop.default-applications.terminal exec-arg "-x"

This modifies the dconf to make terminator the default program. You could also use dconf-editor (a GUI-based tool) to make changes to the dconf, as another answer has suggested. If you would like to learn and understand more about this topic, this may help you.

How to transfer paid android apps from one google account to another google account

You will not be able to do that. You can download apps again to the same userid account on different devices, but you cannot transfer those licenses to other userids.

There is no way to do this programatically - I don't think you can do that practically (except for trying to call customer support at the Play Store).

Tensorflow: how to save/restore a model?

In most cases, saving and restoring from disk using a tf.train.Saver is your best option:

... # build your model
saver = tf.train.Saver()

with tf.Session() as sess:
    ... # train the model
    saver.save(sess, "/tmp/my_great_model")

with tf.Session() as sess:
    saver.restore(sess, "/tmp/my_great_model")
    ... # use the model

You can also save/restore the graph structure itself (see the MetaGraph documentation for details). By default, the Saver saves the graph structure into a .meta file. You can call import_meta_graph() to restore it. It restores the graph structure and returns a Saver that you can use to restore the model's state:

saver = tf.train.import_meta_graph("/tmp/my_great_model.meta")

with tf.Session() as sess:
    saver.restore(sess, "/tmp/my_great_model")
    ... # use the model

However, there are cases where you need something much faster. For example, if you implement early stopping, you want to save checkpoints every time the model improves during training (as measured on the validation set), then if there is no progress for some time, you want to roll back to the best model. If you save the model to disk every time it improves, it will tremendously slow down training. The trick is to save the variable states to memory, then just restore them later:

... # build your model

# get a handle on the graph nodes we need to save/restore the model
graph = tf.get_default_graph()
gvars = graph.get_collection(tf.GraphKeys.GLOBAL_VARIABLES)
assign_ops = [graph.get_operation_by_name(v.op.name + "/Assign") for v in gvars]
init_values = [assign_op.inputs[1] for assign_op in assign_ops]

with tf.Session() as sess:
    ... # train the model

    # when needed, save the model state to memory
    gvars_state = sess.run(gvars)

    # when needed, restore the model state
    feed_dict = {init_value: val
                 for init_value, val in zip(init_values, gvars_state)}
    sess.run(assign_ops, feed_dict=feed_dict)

A quick explanation: when you create a variable X, TensorFlow automatically creates an assignment operation X/Assign to set the variable's initial value. Instead of creating placeholders and extra assignment ops (which would just make the graph messy), we just use these existing assignment ops. The first input of each assignment op is a reference to the variable it is supposed to initialize, and the second input (assign_op.inputs[1]) is the initial value. So in order to set any value we want (instead of the initial value), we need to use a feed_dict and replace the initial value. Yes, TensorFlow lets you feed a value for any op, not just for placeholders, so this works fine.

In Python, how to check if a string only contains certain characters?

This has already been answered satisfactorily, but for people coming across this after the fact, I have done some profiling of several different methods of accomplishing this. In my case I wanted uppercase hex digits, so modify as necessary to suit your needs.

Here are my test implementations:

import re

hex_digits = set("ABCDEF1234567890")
hex_match = re.compile(r'^[A-F0-9]+\Z')
hex_search = re.compile(r'[^A-F0-9]')

def test_set(input):
    return set(input) <= hex_digits

def test_not_any(input):
    return not any(c not in hex_digits for c in input)

def test_re_match1(input):
    return bool(re.compile(r'^[A-F0-9]+\Z').match(input))

def test_re_match2(input):
    return bool(hex_match.match(input))

def test_re_match3(input):
    return bool(re.match(r'^[A-F0-9]+\Z', input))

def test_re_search1(input):
    return not bool(re.compile(r'[^A-F0-9]').search(input))

def test_re_search2(input):
    return not bool(hex_search.search(input))

def test_re_search3(input):
    return not bool(re.match(r'[^A-F0-9]', input))

And the tests, in Python 3.4.0 on Mac OS X:

import cProfile
import pstats
import random

# generate a list of 10000 random hex strings between 10 and 10009 characters long
# this takes a little time; be patient
tests = [ ''.join(random.choice("ABCDEF1234567890") for _ in range(l)) for l in range(10, 10010) ]

# set up profiling, then start collecting stats
test_pr = cProfile.Profile(timeunit=0.000001)
test_pr.enable()

# run the test functions against each item in tests. 
# this takes a little time; be patient
for t in tests:
    for tf in [test_set, test_not_any, 
               test_re_match1, test_re_match2, test_re_match3,
               test_re_search1, test_re_search2, test_re_search3]:
        _ = tf(t)

# stop collecting stats
test_pr.disable()

# we create our own pstats.Stats object to filter 
# out some stuff we don't care about seeing
test_stats = pstats.Stats(test_pr)

# normally, stats are printed with the format %8.3f, 
# but I want more significant digits
# so this monkey patch handles that
def _f8(x):
    return "%11.6f" % x

def _print_title(self):
    print('   ncalls     tottime     percall     cumtime     percall', end=' ', file=self.stream)
    print('filename:lineno(function)', file=self.stream)

pstats.f8 = _f8
pstats.Stats.print_title = _print_title

# sort by cumulative time (then secondary sort by name), ascending
# then print only our test implementation function calls:
test_stats.sort_stats('cumtime', 'name').reverse_order().print_stats("test_*")

which gave the following results:

         50335004 function calls in 13.428 seconds

   Ordered by: cumulative time, function name
   List reduced from 20 to 8 due to restriction 

   ncalls     tottime     percall     cumtime     percall filename:lineno(function)
    10000    0.005233    0.000001    0.367360    0.000037 :1(test_re_match2)
    10000    0.006248    0.000001    0.378853    0.000038 :1(test_re_match3)
    10000    0.010710    0.000001    0.395770    0.000040 :1(test_re_match1)
    10000    0.004578    0.000000    0.467386    0.000047 :1(test_re_search2)
    10000    0.005994    0.000001    0.475329    0.000048 :1(test_re_search3)
    10000    0.008100    0.000001    0.482209    0.000048 :1(test_re_search1)
    10000    0.863139    0.000086    0.863139    0.000086 :1(test_set)
    10000    0.007414    0.000001    9.962580    0.000996 :1(test_not_any)

where:

ncalls
The number of times that function was called
tottime
the total time spent in the given function, excluding time made to sub-functions
percall
the quotient of tottime divided by ncalls
cumtime
the cumulative time spent in this and all subfunctions
percall
the quotient of cumtime divided by primitive calls

The columns we actually care about are cumtime and percall, as that shows us the actual time taken from function entry to exit. As we can see, regex match and search are not massively different.

It is faster not to bother compiling the regex if you would have compiled it every time. It is about 7.5% faster to compile once than every time, but only 2.5% faster to compile than to not compile.

test_set was twice as slow as re_search and thrice as slow as re_match

test_not_any was a full order of magnitude slower than test_set

TL;DR: Use re.match or re.search

Visual Studio debugging/loading very slow

Your "My Documents" folder mapped to a network share?

Startup of IIS Express can take minutes instead of seconds if this is the case even if your solution is local instead of on the network share. In regedit.exe, verify that HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User ShellFolders\Personal is pointing to %USERPROFILE%\My Documents.

If it's not, change it or ask your network admin to make an exception to your policy.

What's the best way to join on the same table twice?

My problem was to display the record even if no or only one phone number exists (full address book). Therefore I used a LEFT JOIN which takes all records from the left, even if no corresponding exists on the right. For me this works in Microsoft Access SQL (they require the parenthesis!)

SELECT t.PhoneNumber1, t.PhoneNumber2, t.PhoneNumber3
   t1.SomeOtherFieldForPhone1, t2.someOtherFieldForPhone2, t3.someOtherFieldForPhone3
FROM 
(
 (
  Table1 AS t LEFT JOIN Table2 AS t3 ON t.PhoneNumber3 = t3.PhoneNumber
 )
 LEFT JOIN Table2 AS t2 ON t.PhoneNumber2 = t2.PhoneNumber
)
LEFT JOIN Table2 AS t1 ON t.PhoneNumber1 = t1.PhoneNumber;

Owl Carousel, making custom navigation

Complete tutorial here

Demo link

enter image description here

JavaScript

$('.owl-carousel').owlCarousel({
    margin: 10,
    nav: true,
    navText:["<div class='nav-btn prev-slide'></div>","<div class='nav-btn next-slide'></div>"],
    responsive: {
        0: {
            items: 1
        },
        600: {
            items: 3
        },
        1000: {
            items: 5
        }
    }
});

CSS Style for navigation

.owl-carousel .nav-btn{
  height: 47px;
  position: absolute;
  width: 26px;
  cursor: pointer;
  top: 100px !important;
}

.owl-carousel .owl-prev.disabled,
.owl-carousel .owl-next.disabled{
pointer-events: none;
opacity: 0.2;
}

.owl-carousel .prev-slide{
  background: url(nav-icon.png) no-repeat scroll 0 0;
  left: -33px;
}
.owl-carousel .next-slide{
  background: url(nav-icon.png) no-repeat scroll -24px 0px;
  right: -33px;
}
.owl-carousel .prev-slide:hover{
 background-position: 0px -53px;
}
.owl-carousel .next-slide:hover{
background-position: -24px -53px;
}   

How to print to the console in Android Studio?

Be careful when using Logcat, it will truncate your message after ~4,076 bytes which can cause a lot of headache if you're printing out large amounts of data.

To get around this you have to write a function that will break it up into multiple parts like so.

How do I add an integer value with javascript (jquery) to a value that's returning a string?

to increment by one you can do something like

  var newValue = currentValue ++;

Printing Python version in output

import sys  

expanded version

sys.version_info  
sys.version_info(major=3, minor=2, micro=2, releaselevel='final', serial=0)

specific

maj_ver = sys.version_info.major  
repr(maj_ver) 
'3'  

or

print(sys.version_info.major)
'3'

or

version = ".".join(map(str, sys.version_info[:3]))
print(version)
'3.2.2'

SFTP in Python? (platform independent)

You should check out pysftp https://pypi.python.org/pypi/pysftp it depends on paramiko, but wraps most common use cases to just a few lines of code.

import pysftp
import sys

path = './THETARGETDIRECTORY/' + sys.argv[1]    #hard-coded
localpath = sys.argv[1]

host = "THEHOST.com"                    #hard-coded
password = "THEPASSWORD"                #hard-coded
username = "THEUSERNAME"                #hard-coded

with pysftp.Connection(host, username=username, password=password) as sftp:
    sftp.put(localpath, path)

print 'Upload done.'

How to thoroughly purge and reinstall postgresql on ubuntu?

I was facing same problem in my ubuntu 16.04

but i fixed that problem and it's very simple just follow these step and you will be able to install postgresql 10 in your system :

Add this to your sources.list:

sudo vim /etc/apt/sources.list

deb http://ftp.de.debian.org/debian/ wheezy main non-free contrib

deb-src http://ftp.de.debian.org/debian/ wheezy main non-free contrib

after that add these link to your pgdg.list file if it's not there you have to create && add link && save it.

sudo vim /etc/apt/sources.list.d/pgdg.list

deb http://apt.postgresql.org/pub/repos/apt/ xenial-pgdg main

deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main

then update your system

sudo apt-get update

sudo apt-get upgrade

and install that unmet dependencies :

apt-get install ssl-cert

that's it. now Install postgresql using these command

sudo apt-get install postgresql-10

How to align title at center of ActionBar in default theme(Theme.Holo.Light)

This actually works:

 getActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
 getActionBar().setCustomView(R.layout.custom_actionbar);
  ActionBar.LayoutParams p = new ActionBar.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
        p.gravity = Gravity.CENTER;

You have to define custom_actionbar.xml layout which is as per your requirement e.g. :

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:background="#2e2e2e"
    android:orientation="vertical"
    android:gravity="center"
    android:layout_gravity="center">

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/top_banner"
        android:layout_gravity="center"
        />
</LinearLayout>

Html helper for <input type="file" />

Improved version of Paulius Zaliaduonis' answer:

In order to make the validation work properly I had to change the Model to:

public class ViewModel
{
      public HttpPostedFileBase File { get; set; }

        [Required(ErrorMessage="A header image is required"), FileExtensions(ErrorMessage = "Please upload an image file.")]
        public string FileName
        {
            get
            {
                if (File != null)
                    return File.FileName;
                else
                    return String.Empty;
            }
        }
}

and the view to:

@using (Html.BeginForm("Action", "Controller", FormMethod.Post, new 
                                       { enctype = "multipart/form-data" }))
{
    @Html.TextBoxFor(m => m.File, new { type = "file" })
    @Html.ValidationMessageFor(m => m.FileName)
}

This is required because what @Serj Sagan wrote about FileExtension attribute working only with strings.

Notepad++ incrementally replace

Not sure about regex, but there is a way for you to do this in Notepad++, although it isn't very flexible.

In the example that you gave, hold Alt and select the column of numbers that you wish to change. Then go to Edit->Column Editor and select the Number to Insert radio button in the window that appears. Then specify your initial number and increment, and hit OK. It should write out the incremented numbers.

Note: this also works with the Multi-editing feature (selecting several locations while maintaining Ctrl key pressed).

This is, however, not anywhere near the flexibility that most people would find useful. Notepad++ is great, but if you want a truly powerful editor that can do things like this with ease, I'd say use Vim.

Paste MS Excel data to SQL Server

why not just use export/import wizard in SSMS?

How to run the Python program forever?

How about this one?

import signal
signal.pause()

This will let your program sleep until it receives a signal from some other process (or itself, in another thread), letting it know it is time to do something.

Add column to dataframe with constant value

You can use insert to specify where you want to new column to be. In this case, I use 0 to place the new column at the left.

df.insert(0, 'Name', 'abc')

  Name        Date  Open  High  Low  Close
0  abc  01-01-2015   565   600  400    450

What is the difference between for and foreach?

Many answers are already there, I just need to identify one difference which is not there.

for loop is fail-safe while foreach loop is fail-fast.

Fail-fast iteration throws ConcurrentModificationException if iteration and modification are done at the same time in object.

However, fail-safe iteration keeps the operation safe from failing even if the iteration goes in infinite loop.

public class ConcurrentModification {
    public static void main(String[] args) {
        List<String> str = new ArrayList<>();

        for(int i=0; i<1000; i++){
            str.add(String.valueOf(i));
        }

        /**
         * this for loop is fail-safe. It goes into infinite loop but does not fail. 
         */
        for(int i=0; i<str.size(); i++){
            System.out.println(str.get(i));
            str.add(i+ "  " + "10");
        }

        /**
         * throws ConcurrentModificationexception 
        for(String st: str){
            System.out.println(st);
            str.add("10");
        }
        */

        /* throws ConcurrentModificationException 
         Iterator<String> itr = str.iterator();
        while(itr.hasNext()) {
            System.out.println(itr.next());
            str.add("10");
        }*/
    }
} 

Hope this helps to understand the difference between for and foreach loop through different angle.

I found a good blog to go through the differences between fail-safe and fail-fast, if anyone interested:

In javascript, how do you search an array for a substring match

ref: In javascript, how do you search an array for a substring match

The solution given here is generic unlike the solution 4556343#4556343, which requires a previous parse to identify a string with which to join(), that is not a component of any of the array strings.
Also, in that code /!id-[^!]*/ is more correctly, /![^!]*id-[^!]*/ to suit the question parameters:

  1. "search an array ..." (of strings or numbers and not functions, arrays, objects, etc.)
  2. "for only part of the string to match " (match can be anywhere)
  3. "return the ... matched ... element" (singular, not ALL, as in "... the ... elementS")
  4. "with the full string" (include the quotes)

... NetScape / FireFox solutions (see below for a JSON solution):

javascript:         /* "one-liner" statement solution */
   alert(
      ["x'!x'\"id-2",'\' "id-1 "',   "item","thing","id-3-text","class" ] .
         toSource() . match( new RegExp( 
            '[^\\\\]("([^"]|\\\\")*' + 'id-' + '([^"]|\\\\")*[^\\\\]")' ) ) [1]
   );

or

javascript:
   ID = 'id-' ;
   QS = '([^"]|\\\\")*' ;           /* only strings with escaped double quotes */
   RE = '[^\\\\]("' +QS+ ID +QS+ '[^\\\\]")' ;/* escaper of escaper of escaper */
   RE = new RegExp( RE ) ;
   RA = ["x'!x'\"id-2",'\' "id-1 "',   "item","thing","id-3-text","class" ] ;
   alert(RA.toSource().match(RE)[1]) ;

displays "x'!x'\"id-2".
Perhaps raiding the array to find ALL matches is 'cleaner'.

/* literally (? backslash star escape quotes it!) not true, it has this one v  */
javascript:                            /* purely functional - it has no ... =! */
   RA = ["x'!x'\"id-2",'\' "id-1 "',   "item","thing","id-3-text","class" ] ;
   function findInRA(ra,id){
      ra.unshift(void 0) ;                                     /* cheat the [" */
      return ra . toSource() . match( new RegExp(
             '[^\\\\]"' + '([^"]|\\\\")*' + id + '([^"]|\\\\")*' + '[^\\\\]"' ,
             'g' ) ) ;
   }
   alert( findInRA( RA, 'id-' ) . join('\n\n') ) ;

displays:

     "x'!x'\"id-2"

     "' \"id-1 \""

     "id-3-text"

Using, JSON.stringify():

javascript:                             /* needs prefix cleaning */
   RA = ["x'!x'\"id-2",'\' "id-1 "',   "item","thing","id-3-text","class" ] ;
   function findInRA(ra,id){
      return JSON.stringify( ra ) . match( new RegExp(
             '[^\\\\]"([^"]|\\\\")*' + id + '([^"]|\\\\")*[^\\\\]"' ,
             'g' ) ) ;
   }
   alert( findInRA( RA, 'id-' ) . join('\n\n') ) ;

displays:

    ["x'!x'\"id-2"

    ,"' \"id-1 \""

    ,"id-3-text"

wrinkles:

  • The "unescaped" global RegExp is /[^\]"([^"]|\")*id-([^"]|\")*[^\]"/g with the \ to be found literally. In order for ([^"]|\")* to match strings with all "'s escaped as \", the \ itself must be escaped as ([^"]|\\")*. When this is referenced as a string to be concatenated with id-, each \ must again be escaped, hence ([^"]|\\\\")*!
  • A search ID that has a \, *, ", ..., must also be escaped via .toSource() or JSON or ... .
  • null search results should return '' (or "" as in an EMPTY string which contains NO "!) or [] (for all search).
  • If the search results are to be incorporated into the program code for further processing, then eval() is necessary, like eval('['+findInRA(RA,ID).join(',')+']').

--------------------------------------------------------------------------------

Digression:
Raids and escapes? Is this code conflicted?
The semiotics, syntax and semantics of /* it has no ... =! */ emphatically elucidates the escaping of quoted literals conflict.

Does "no =" mean:

  • "no '=' sign" as in javascript:alert('\x3D') (Not! Run it and see that there is!),
  • "no javascript statement with the assignment operator",
  • "no equal" as in "nothing identical in any other code" (previous code solutions demonstrate there are functional equivalents),
  • ...

Quoting on another level can also be done with the immediate mode javascript protocol URI's below. (// commentaries end on a new line (aka nl, ctrl-J, LineFeed, ASCII decimal 10, octal 12, hex A) which requires quoting since inserting a nl, by pressing the Return key, invokes the URI.)

javascript:/* a comment */  alert('visible')                                ;
javascript:// a comment ;   alert(  'not'  ) this is all comment             %0A;
javascript:// a comment %0A alert('visible but  %\0A  is wrong ')   // X     %0A
javascript:// a comment %0A alert('visible but %'+'0A is a pain to type')   ;

Note: Cut and paste any of the javascript: lines as an immediate mode URI (at least, at most?, in FireFox) to use first javascript: as a URI scheme or protocol and the rest as JS labels.

Concatenating strings in Razor

You can use:

@foreach (var item in Model)
{
  ...
  @Html.DisplayFor(modelItem => item.address + " " + item.city) 
  ...

How to add headers to a multicolumn listbox in an Excel userform using VBA

Here's one approach which automates creating labels above each column of a listbox (on a worksheet).

It will work (though not super-pretty!) as long as there's no horizontal scrollbar on your listbox.

Sub Tester()
Dim i As Long

With Me.lbTest
    .Clear
    .ColumnCount = 5
    'must do this next step!
    .ColumnWidths = "70;60;100;60;60"
    .ListStyle = fmListStylePlain
    Debug.Print .ColumnWidths
    For i = 0 To 10
        .AddItem
        .List(i, 0) = "blah" & i
        .List(i, 1) = "blah"
        .List(i, 2) = "blah"
        .List(i, 3) = "blah"
        .List(i, 4) = "blah"
    Next i

End With

LabelHeaders Me.lbTest, Array("Header1", "Header2", _
                     "Header3", "Header4", "Header5")

End Sub

Sub LabelHeaders(lb, arrHeaders)

    Const LBL_HT As Long = 15
    Dim T, L, shp As Shape, cw As String, arr
    Dim i As Long, w

    'delete any previous headers for this listbox
    For i = lb.Parent.Shapes.Count To 1 Step -1
        If lb.Parent.Shapes(i).Name Like lb.Name & "_*" Then
            lb.Parent.Shapes(i).Delete
        End If
    Next i

    'get an array of column widths
    cw = lb.ColumnWidths
    If Len(cw) = 0 Then Exit Sub
    cw = Replace(cw, " pt", "")
    arr = Split(cw, ";")

    'start points for labels
    T = lb.Top - LBL_HT
    L = lb.Left

    For i = LBound(arr) To UBound(arr)
        w = CLng(arr(i))
        If i = UBound(arr) And (L + w) < lb.Width Then w = lb.Width - L
        Set shp = ActiveSheet.Shapes.AddShape(msoShapeRectangle, _
                                         L, T, w, LBL_HT)
        With shp
            .Name = lb.Name & "_" & i
            'do some formatting
            .Line.ForeColor.RGB = vbBlack
            .Line.Weight = 1
            .Fill.ForeColor.RGB = RGB(220, 220, 220)
            .TextFrame2.TextRange.Characters.Text = arrHeaders(i)
            .TextFrame2.TextRange.Font.Size = 9
            .TextFrame2.TextRange.Font.Fill.ForeColor.RGB = vbBlack
        End With
        L = L + w
    Next i
End Sub

Python - Dimension of Data Frame

df.shape, where df is your DataFrame.

Set Focus on EditText

My answer here

As I read on the official document, I think this is the best answer, just pass the View to parameter such as your EditText, but showSoftKeyboard seems like not working on landscape

private fun showSoftKeyboard(view: View) {
    if (view.requestFocus()) {
        val imm = getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        imm.showSoftInput(view, InputMethodManager.SHOW_IMPLICIT)
    }
}

private fun closeSoftKeyboard(view: View) {
    if (view.requestFocus()) {
        val imm = getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        imm.hideSoftInputFromWindow(view.windowToken, InputMethodManager.HIDE_NOT_ALWAYS)
    }
}

How do I print out the value of this boolean? (Java)

There are several problems.

One is of style; always capitalize class names. This is a universally observed Java convention. Failing to do so confuses other programmers.

Secondly, the line

System.out.println(boolean isLeapYear);

is a syntax error. Delete it.

Thirdly.

You never call the function from your main routine. That is why you never see any reply to the input.

JavaScript alert not working in Android WebView

You can try with this, it worked for me

WebView wb_previewSurvey=new WebView(this); 


       wb_previewSurvey.setWebChromeClient(new WebChromeClient() {
        @Override
        public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
            //Required functionality here
            return super.onJsAlert(view, url, message, result);
        }

    });

How schedule build in Jenkins?

To build once a day between say 4PM to 6PM you can use

H H(15-17) * * *

Pass props to parent component in React.js

Edit: see the end examples for ES6 updated examples.

This answer simply handle the case of direct parent-child relationship. When parent and child have potentially a lot of intermediaries, check this answer.

Other solutions are missing the point

While they still work fine, other answers are missing something very important.

Is there not a simple way to pass a child's props to its parent using events, in React.js?

The parent already has that child prop!: if the child has a prop, then it is because its parent provided that prop to the child! Why do you want the child to pass back the prop to the parent, while the parent obviously already has that prop?

Better implementation

Child: it really does not have to be more complicated than that.

var Child = React.createClass({
  render: function () {
    return <button onClick={this.props.onClick}>{this.props.text}</button>;
  },
});

Parent with single child: using the value it passes to the child

var Parent = React.createClass({
  getInitialState: function() {
     return {childText: "Click me! (parent prop)"};
  },
  render: function () {
    return (
      <Child onClick={this.handleChildClick} text={this.state.childText}/>
    );
  },
  handleChildClick: function(event) {
     // You can access the prop you pass to the children 
     // because you already have it! 
     // Here you have it in state but it could also be
     //  in props, coming from another parent.
     alert("The Child button text is: " + this.state.childText);
     // You can also access the target of the click here 
     // if you want to do some magic stuff
     alert("The Child HTML is: " + event.target.outerHTML);
  }
});

JsFiddle

Parent with list of children: you still have everything you need on the parent and don't need to make the child more complicated.

var Parent = React.createClass({
  getInitialState: function() {
     return {childrenData: [
         {childText: "Click me 1!", childNumber: 1},
         {childText: "Click me 2!", childNumber: 2}
     ]};
  },
  render: function () {
    var children = this.state.childrenData.map(function(childData,childIndex) {
        return <Child onClick={this.handleChildClick.bind(null,childData)} text={childData.childText}/>;
    }.bind(this));
    return <div>{children}</div>;
  },

  handleChildClick: function(childData,event) {
     alert("The Child button data is: " + childData.childText + " - " + childData.childNumber);
     alert("The Child HTML is: " + event.target.outerHTML);
  }
});

JsFiddle

It is also possible to use this.handleChildClick.bind(null,childIndex) and then use this.state.childrenData[childIndex]

Note we are binding with a null context because otherwise React issues a warning related to its autobinding system. Using null means you don't want to change the function context. See also.

About encapsulation and coupling in other answers

This is for me a bad idea in term of coupling and encapsulation:

var Parent = React.createClass({
  handleClick: function(childComponent) {
     // using childComponent.props
     // using childComponent.refs.button
     // or anything else using childComponent
  },
  render: function() {
    <Child onClick={this.handleClick} />
  }
});

Using props: As I explained above, you already have the props in the parent so it's useless to pass the whole child component to access props.

Using refs: You already have the click target in the event, and in most case this is enough. Additionnally, you could have used a ref directly on the child:

<Child ref="theChild" .../>

And access the DOM node in the parent with

React.findDOMNode(this.refs.theChild)

For more advanced cases where you want to access multiple refs of the child in the parent, the child could pass all the dom nodes directly in the callback.

The component has an interface (props) and the parent should not assume anything about the inner working of the child, including its inner DOM structure or which DOM nodes it declares refs for. A parent using a ref of a child means that you tightly couple the 2 components.

To illustrate the issue, I'll take this quote about the Shadow DOM, that is used inside browsers to render things like sliders, scrollbars, video players...:

They created a boundary between what you, the Web developer can reach and what’s considered implementation details, thus inaccessible to you. The browser however, can traipse across this boundary at will. With this boundary in place, they were able to build all HTML elements using the same good-old Web technologies, out of the divs and spans just like you would.

The problem is that if you let the child implementation details leak into the parent, you make it very hard to refactor the child without affecting the parent. This means as a library author (or as a browser editor with Shadow DOM) this is very dangerous because you let the client access too much, making it very hard to upgrade code without breaking retrocompatibility.

If Chrome had implemented its scrollbar letting the client access the inner dom nodes of that scrollbar, this means that the client may have the possibility to simply break that scrollbar, and that apps would break more easily when Chrome perform its auto-update after refactoring the scrollbar... Instead, they only give access to some safe things like customizing some parts of the scrollbar with CSS.

About using anything else

Passing the whole component in the callback is dangerous and may lead novice developers to do very weird things like calling childComponent.setState(...) or childComponent.forceUpdate(), or assigning it new variables, inside the parent, making the whole app much harder to reason about.


Edit: ES6 examples

As many people now use ES6, here are the same examples for ES6 syntax

The child can be very simple:

const Child = ({
  onClick, 
  text
}) => (
  <button onClick={onClick}>
    {text}
  </button>
)

The parent can be either a class (and it can eventually manage the state itself, but I'm passing it as props here:

class Parent1 extends React.Component {
  handleChildClick(childData,event) {
     alert("The Child button data is: " + childData.childText + " - " + childData.childNumber);
     alert("The Child HTML is: " + event.target.outerHTML);
  }
  render() {
    return (
      <div>
        {this.props.childrenData.map(child => (
          <Child
            key={child.childNumber}
            text={child.childText} 
            onClick={e => this.handleChildClick(child,e)}
          />
        ))}
      </div>
    );
  }
}

But it can also be simplified if it does not need to manage state:

const Parent2 = ({childrenData}) => (
  <div>
     {childrenData.map(child => (
       <Child
         key={child.childNumber}
         text={child.childText} 
         onClick={e => {
            alert("The Child button data is: " + child.childText + " - " + child.childNumber);
                    alert("The Child HTML is: " + e.target.outerHTML);
         }}
       />
     ))}
  </div>
)

JsFiddle


PERF WARNING (apply to ES5/ES6): if you are using PureComponent or shouldComponentUpdate, the above implementations will not be optimized by default because using onClick={e => doSomething()}, or binding directly during the render phase, because it will create a new function everytime the parent renders. If this is a perf bottleneck in your app, you can pass the data to the children, and reinject it inside "stable" callback (set on the parent class, and binded to this in class constructor) so that PureComponent optimization can kick in, or you can implement your own shouldComponentUpdate and ignore the callback in the props comparison check.

You can also use Recompose library, which provide higher order components to achieve fine-tuned optimisations:

// A component that is expensive to render
const ExpensiveComponent = ({ propA, propB }) => {...}

// Optimized version of same component, using shallow comparison of props
// Same effect as React's PureRenderMixin
const OptimizedComponent = pure(ExpensiveComponent)

// Even more optimized: only updates if specific prop keys have changed
const HyperOptimizedComponent = onlyUpdateForKeys(['propA', 'propB'])(ExpensiveComponent)

In this case you could optimize the Child component by using:

const OptimizedChild = onlyUpdateForKeys(['text'])(Child)

How to pass anonymous types as parameters?

I would use IEnumerable<object> as type for the argument. However not a great gain for the unavoidable explicit cast. Cheers

fatal error LNK1104: cannot open file 'kernel32.lib'

Check the VC++ directories, in VS 2010 these can be found in your project properties. Check whether $(WindowsSdkDir)\lib is included in the directories list, if not, manually add it. If you're building for X64 platform, you should select X64 from the “Platform” ComboBox, and make sure that $(WindowsSdkDir)\lib\x64 is included in the directories list.

What is Mocking?

If your mock involves a network request, another alternative is to have a real test server to hit. You can use a service to generate a request and response for your testing.

Does Notepad++ show all hidden characters?

Yes, and unfortunately you cannot turn them off, or any other special characters. The options under \View\Show Symbols only turns on or off things like tabs, spaces, EOL, etc. So if you want to read some obscure coding with text in it - you actually need to look elsewhere. I also looked at changing the coding, ASCII is not listed, and that would not make the mess invisible anyway.

SQL MERGE statement to update data

UPDATE ed
SET ed.kWh = ted.kWh
FROM energydata ed
INNER JOIN temp_energydata ted ON ted.webmeterID = ed.webmeterID

How to get the squared symbol (²) to display in a string

Not sure what kind of text box you are refering to. However, I'm not sure if you can do this in a text box on a user form.

A text box on a sheet you can though.

Sheets("Sheet1").Shapes("TextBox 1").TextFrame2.TextRange.Text = "R2=" & variable
Sheets("Sheet1").Shapes("TextBox 1").TextFrame2.TextRange.Characters(2, 1).Font.Superscript = msoTrue

And same thing for an excel cell

Sheets("Sheet1").Range("A1").Characters(2, 1).Font.Superscript = True

If this isn't what you're after you will need to provide more information in your question.

EDIT: posted this after the comment sorry

System.BadImageFormatException: Could not load file or assembly

It seems that you are using the 64-bit version of the tool to install a 32-bit/x86 architecture application. Look for the 32-bit version of the tool here:

C:\Windows\Microsoft.NET\Framework\v4.0.30319

and it should install your 32-bit application just fine.

Efficient SQL test query or validation query that will work across all (or most) databases

For Oracle the high performing query will be

select 'X' from <your_small_table> where <primay_key_coulmn> = <some_value>

This is from a performance perspective.

How to deploy correctly when using Composer's develop / production switch?

On production servers I rename vendor to vendor-<datetime>, and during deployment will have two vendor dirs.

A HTTP cookie causes my system to choose the new vendor autoload.php, and after testing I do a fully atomic/instant switch between them to disable the old vendor dir for all future requests, then I delete the previous dir a few days later.

This avoids any problem caused by filesystem caches I'm using in apache/php, and also allows any active PHP code to continue using the previous vendor dir.


Despite other answers recommending against it, I personally run composer install on the server, since this is faster than rsync from my staging area (a VM on my laptop).

I use --no-dev --no-scripts --optimize-autoloader. You should read the docs for each one to check if this is appropriate on your environment.

ExecuteReader: Connection property has not been initialized

You can also write this:

SqlCommand cmd=new SqlCommand ("insert into time(project,iteration) values (@project, @iteration)", conn);
cmd.Parameters.AddWithValue("@project",name1.SelectedValue);
cmd.Parameters.AddWithValue("@iteration",iteration.SelectedValue);

How to respond with HTTP 400 error in a Spring MVC @ResponseBody method returning String?

I think this thread actually has the easiest, cleanest solution, that does not sacrifice the JSON martialing tools that Spring provides:

https://stackoverflow.com/a/16986372/1278921

Javascript How to define multiple variables on a single line?

Using Javascript's es6 or node, you can do the following:

var [a,b,c,d] = [0,1,2,3]

And if you want to easily print multiple variables in a single line, just do this:

console.log(a, b, c, d)

0 1 2 3

This is similar to @alex gray 's answer here, but this example is in Javascript instead of CoffeeScript.

Note that this uses Javascript's array destructuring assignment

jQuery Form Validation before Ajax submit

I think that i first validate form and if validation will pass, than i would make ajax post. Dont forget to add "return false" at the end of the script.

Is there a way to remove unused imports and declarations from Angular 2+?

As of Visual Studio Code Release 1.22 this comes free without the need of an extension.

Shift+Alt+O will take care of you.

How to install 2 Anacondas (Python 2 and 3) on Mac OS

There is no need to install Anaconda again. Conda, the package manager for Anaconda, fully supports separated environments. The easiest way to create an environment for Python 2.7 is to do

conda create -n python2 python=2.7 anaconda

This will create an environment named python2 that contains the Python 2.7 version of Anaconda. You can activate this environment with

source activate python2

This will put that environment (typically ~/anaconda/envs/python2) in front in your PATH, so that when you type python at the terminal it will load the Python from that environment.

If you don't want all of Anaconda, you can replace anaconda in the command above with whatever packages you want. You can use conda to install packages in that environment later, either by using the -n python2 flag to conda, or by activating the environment.

How to pass an array to a function in VBA?

Your function worked for me after changing its declaration to this ...

Function processArr(Arr As Variant) As String

You could also consider a ParamArray like this ...

Function processArr(ParamArray Arr() As Variant) As String
    'Dim N As Variant
    Dim N As Long
    Dim finalStr As String
    For N = LBound(Arr) To UBound(Arr)
        finalStr = finalStr & Arr(N)
    Next N
    processArr = finalStr
End Function

And then call the function like this ...

processArr("foo", "bar")

GDB: Listing all mapped memory regions for a crashed process

In GDB 7.2:

(gdb) help info proc
Show /proc process information about any running process.
Specify any process id, or use the program being debugged by default.
Specify any of the following keywords for detailed info:
  mappings -- list of mapped memory regions.
  stat     -- list a bunch of random process info.
  status   -- list a different bunch of random process info.
  all      -- list all available /proc info.

You want info proc mappings, except it doesn't work when there is no /proc (such as during pos-mortem debugging).

Try maintenance info sections instead.

Loop through childNodes

I'm very late to the party, but since element.lastChild.nextSibling === null, the following seems like the most straightforward option to me:

for(var child=element.firstChild; child!==null; child=child.nextSibling) {
    console.log(child);
}

How to convert (transliterate) a string from utf8 to ASCII (single byte) in c#?

This was in response to your other question, that looks like it's been deleted....the point still stands.

Looks like a classic Unicode to ASCII issue. The trick would be to find where it's happening.

.NET works fine with Unicode, assuming it's told it's Unicode to begin with (or left at the default).

My guess is that your receiving app can't handle it. So, I'd probably use the ASCIIEncoder with an EncoderReplacementFallback with String.Empty:

using System.Text;

string inputString = GetInput();
var encoder = ASCIIEncoding.GetEncoder();
encoder.Fallback = new EncoderReplacementFallback(string.Empty);

byte[] bAsciiString = encoder.GetBytes(inputString);

// Do something with bytes...
// can write to a file as is
File.WriteAllBytes(FILE_NAME, bAsciiString);
// or turn back into a "clean" string
string cleanString = ASCIIEncoding.GetString(bAsciiString); 
// since the offending bytes have been removed, can use default encoding as well
Assert.AreEqual(cleanString, Default.GetString(bAsciiString));

Of course, in the old days, we'd just loop though and remove any chars greater than 127...well, those of us in the US at least. ;)

Copy Paste in Bash on Ubuntu on Windows

Ok, it's developed finally and now you are able to use Ctrl+Shift+C/V to Copy/Paste as of Windows 10 Insider build #17643.

You'll need to enable the "Use Ctrl+Shift+C/V as Copy/Paste" option in the Console "Options" properties page:

enter image description here

referenced in blogs.msdn.microsoft.com/

Python - A keyboard command to stop infinite loop?

Ctrl+C is what you need. If it didn't work, hit it harder. :-) Of course, you can also just close the shell window.

Edit: You didn't mention the circumstances. As a last resort, you could write a batch file that contains taskkill /im python.exe, and put it on your desktop, Start menu, etc. and run it when you need to kill a runaway script. Of course, it will kill all Python processes, so be careful.

button image as form input submit button?

You can also use a second image to give the effect of a button being pressed. Just add the "pressed" button image in the HTML before the input image:

<img src="http://integritycontractingofva.com/images/go2.jpg" id="pressed"/>
<input id="unpressed" type="submit" value=" " style="background:url(http://integritycontractingofva.com/images/go1.jpg) no-repeat;border:none;"/>

And use CSS to change the opacity of the "unpressed" image on hover:

#pressed, #unpressed{position:absolute; left:0px;}
#unpressed{opacity: 1; cursor: pointer;}
#unpressed:hover{opacity: 0;}

I use it for the blue "GO" button on this page

How to pass multiple arguments in processStartInfo?

startInfo.Arguments = "/c \"netsh http add sslcert ipport=127.0.0.1:8085 certhash=0000000000003ed9cd0c315bbb6dc1c08da5e6 appid={00112233-4455-6677-8899-AABBCCDDEEFF} clientcertnegotiation=enable\"";

and...

startInfo.Arguments = "/c \"makecert -sk server -sky exchange -pe -n CN=localhost -ir LocalMachine -is Root -ic MyCA.cer -sr LocalMachine -ss My MyAdHocTestCert.cer\"";

The /c tells cmd to quit once the command has completed. Everything after /c is the command you want to run (within cmd), including all of the arguments.

What is the difference between logical data model and conceptual data model?

In this table you can see the difference between each model: Difference between data models

See http://www.1keydata.com/datawarehousing/data-modeling-levels.html for more information and some data model examples.

How do I concatenate const/literal strings in C?

Avoid using strcat in C code. The cleanest and, most importantly, the safest way is to use snprintf:

char buf[256];
snprintf(buf, sizeof buf, "%s%s%s%s", str1, str2, str3, str4);

Some commenters raised an issue that the number of arguments may not match the format string and the code will still compile, but most compilers already issue a warning if this is the case.

Class is not abstract and does not override abstract method

Both classes Rectangle and Ellipse need to override both of the abstract methods.

To work around this, you have 3 options:

  • Add the two methods
  • Make each class that extends Shape abstract
  • Have a single method that does the function of the classes that will extend Shape, and override that method in Rectangle and Ellipse, for example:

    abstract class Shape {
        // ...
        void draw(Graphics g);
    }
    

And

    class Rectangle extends Shape {
        void draw(Graphics g) {
            // ...
        }
    }

Finally

    class Ellipse extends Shape {
        void draw(Graphics g) {
            // ...
        }
    }

And you can switch in between them, like so:

    Shape shape = new Ellipse();
    shape.draw(/* ... */);

    shape = new Rectangle();
    shape.draw(/* ... */);

Again, just an example.

How to add minutes to my Date

The issue for you is that you are using mm. You should use MM. MM is for month and mm is for minutes. Try with yyyy-MM-dd HH:mm

Other approach:

It can be as simple as this (other option is to use joda-time)

static final long ONE_MINUTE_IN_MILLIS=60000;//millisecs

Calendar date = Calendar.getInstance();
long t= date.getTimeInMillis();
Date afterAddingTenMins=new Date(t + (10 * ONE_MINUTE_IN_MILLIS));

How do I execute a command and get the output of the command within C++ using POSIX?

For Windows, popen also works, but it opens up a console window - which quickly flashes over your UI application. If you want to be a professional, it's better to disable this "flashing" (especially if the end-user can cancel it).

So here is my own version for Windows:

(This code is partially recombined from ideas written in The Code Project and MSDN samples.)

#include <windows.h>
#include <atlstr.h>
//
// Execute a command and get the results. (Only standard output)
//
CStringA ExecCmd(
    const wchar_t* cmd              // [in] command to execute
)
{
    CStringA strResult;
    HANDLE hPipeRead, hPipeWrite;

    SECURITY_ATTRIBUTES saAttr = {sizeof(SECURITY_ATTRIBUTES)};
    saAttr.bInheritHandle = TRUE; // Pipe handles are inherited by child process.
    saAttr.lpSecurityDescriptor = NULL;

    // Create a pipe to get results from child's stdout.
    if (!CreatePipe(&hPipeRead, &hPipeWrite, &saAttr, 0))
        return strResult;

    STARTUPINFOW si = {sizeof(STARTUPINFOW)};
    si.dwFlags     = STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES;
    si.hStdOutput  = hPipeWrite;
    si.hStdError   = hPipeWrite;
    si.wShowWindow = SW_HIDE; // Prevents cmd window from flashing.
                              // Requires STARTF_USESHOWWINDOW in dwFlags.

    PROCESS_INFORMATION pi = { 0 };

    BOOL fSuccess = CreateProcessW(NULL, (LPWSTR)cmd, NULL, NULL, TRUE, CREATE_NEW_CONSOLE, NULL, NULL, &si, &pi);
    if (! fSuccess)
    {
        CloseHandle(hPipeWrite);
        CloseHandle(hPipeRead);
        return strResult;
    }

    bool bProcessEnded = false;
    for (; !bProcessEnded ;)
    {
        // Give some timeslice (50 ms), so we won't waste 100% CPU.
        bProcessEnded = WaitForSingleObject( pi.hProcess, 50) == WAIT_OBJECT_0;

        // Even if process exited - we continue reading, if
        // there is some data available over pipe.
        for (;;)
        {
            char buf[1024];
            DWORD dwRead = 0;
            DWORD dwAvail = 0;

            if (!::PeekNamedPipe(hPipeRead, NULL, 0, NULL, &dwAvail, NULL))
                break;

            if (!dwAvail) // No data available, return
                break;

            if (!::ReadFile(hPipeRead, buf, min(sizeof(buf) - 1, dwAvail), &dwRead, NULL) || !dwRead)
                // Error, the child process might ended
                break;

            buf[dwRead] = 0;
            strResult += buf;
        }
    } //for

    CloseHandle(hPipeWrite);
    CloseHandle(hPipeRead);
    CloseHandle(pi.hProcess);
    CloseHandle(pi.hThread);
    return strResult;
} //ExecCmd

AutoComplete TextBox in WPF

Nimgoble's is the version I used in 2015. Thought I'd put it here as this question was top of the list in google for "wpf autocomplete textbox"

  1. Install nuget package for project in Visual Studio

  2. Add a reference to the library in the xaml:
    xmlns:behaviors="clr-namespace:WPFTextBoxAutoComplete;assembly=WPFTextBoxAutoComplete"

  3. Create a textbox and bind the AutoCompleteBehaviour to List<String> (TestItems):
    <TextBox Text="{Binding TestText, UpdateSourceTrigger=PropertyChanged}" behaviors:AutoCompleteBehavior.AutoCompleteItemsSource="{Binding TestItems}" />

IMHO this is much easier to get started and manage than the other options listed above.

iOS: present view controller programmatically

If you are using Storyboard and your "add" viewController is in storyboard then set an identifier for your "add" viewcontroller in settings so you can do something like this:

UIStoryboard* storyboard = [UIStoryboard storyboardWithName:@"NameOfYourStoryBoard" 
                                                     bundle:nil];
AddTaskViewController *add = 
           [storyboard instantiateViewControllerWithIdentifier:@"viewControllerIdentifier"];

[self presentViewController:add 
                   animated:YES 
                 completion:nil];

if you do not have your "add" viewController in storyboard or a nib file and want to create the whole thing programmaticaly then appDocs says:

If you cannot define your views in a storyboard or a nib file, override the loadView method to manually instantiate a view hierarchy and assign it to the view property.

Don't reload application when orientation changes

As Pacerier mentioned,

android:configChanges="orientation|screenSize"

Simple working Example of json.net in VB.net

In Place of using this

MsgBox(json.SelectToken("Venue").SelectToken("ID"))

You can also use

MsgBox(json.SelectToken("Venue.ID"))

What does "select count(1) from table_name" on any database tables mean?

Depending on who you ask, some people report that executing select count(1) from random_table; runs faster than select count(*) from random_table. Others claim they are exactly the same.

This link claims that the speed difference between the 2 is due to a FULL TABLE SCAN vs FAST FULL SCAN.

How to run specific test cases in GoogleTest

Finally I got some answer, ::test::GTEST_FLAG(list_tests) = true; //From your program, not w.r.t console.

If you would like to use --gtest_filter =*; /* =*, =xyz*... etc*/ // You need to use them in Console.

So, my requirement is to use them from the program not from the console.

Updated:-

Finally I got the answer for updating the same in from the program.

 ::testing::GTEST_FLAG(filter) = "*Counter*:*IsPrime*:*ListenersTest.DoesNotLeak*";//":-:*Counter*";
      InitGoogleTest(&argc, argv);
RUN_ALL_TEST();

So, Thanks for all the answers.

You people are great.

How to create loading dialogs in Android?

Today things have changed a little.

Now we avoid use ProgressDialog to show spinning progress:

enter image description here

If you want to put in your app a spinning progress you should use an Activity indicators:

http://developer.android.com/design/building-blocks/progress.html#activity

What's the difference between Visual Studio Community and other, paid versions?

There are 2 major differences.

  1. Technical
  2. Licensing

Technical, there are 3 major differences:

First and foremost, Community doesn't have TFS support.
You'll just have to use git (arguable whether this constitutes a disadvantage or whether this actually is a good thing).
Note: This is what MS wrote. Actually, you can check-in&out with TFS as normal, if you have a TFS server in the network. You just cannot use Visual Studio as TFS SERVER.

Second, VS Community is severely limited in its testing capability.
Only unit tests. No Performance tests, no load tests, no performance profiling.

Third, VS Community's ability to create Virtual Environments has been severely cut.

On the other hand, syntax highlighting, IntelliSense, Step-Through debugging, GoTo-Definition, Git-Integration and Build/Publish are really all the features I need, and I guess that applies to a lot of developers.

For all other things, there are tools that do the same job faster, better and cheaper.

If you, like me, anyway use git, do unit testing with NUnit, and use Java-Tools to do Load-Testing on Linux plus TeamCity for CI, VS Community is more than sufficient, technically speaking.

Licensing:

A) If you're an individual developer (no enterprise, no organization), no difference (AFAIK), you can use CommunityEdition like you'd use the paid edition (as long as you don't do subcontracting)
B) You can use CommunityEdition freely for OpenSource (OSI) projects
C) If you're an educational insitution, you can use CommunityEdition freely (for education/classroom use)
D) If you're an enterprise with 250 PCs or users or more than one million US dollars in revenue (including subsidiaries), you are NOT ALLOWED to use CommunityEdition.
E) If you're not an enterprise as defined above, and don't do OSI or education, but are an "enterprise"/organization, with 5 or less concurrent (VS) developers, you can use VS Community freely (but only if you're the owner of the software and sell it, not if you're a subcontractor creating software for a larger enterprise, software which in the end the enterprise will own), otherwise you need a paid edition.

The above does not consitute legal advise.
See also:
https://softwareengineering.stackexchange.com/questions/262916/understanding-visual-studio-community-edition-license

Python: Append item to list N times

l = []
x = 0
l.extend([x]*100)

How might I find the largest number contained in a JavaScript array?

You can also use forEach:

_x000D_
_x000D_
var maximum = Number.MIN_SAFE_INTEGER;_x000D_
_x000D_
var array = [-3, -2, 217, 9, -8, 46];_x000D_
array.forEach(function(value){_x000D_
  if(value > maximum) {_x000D_
    maximum = value;_x000D_
  }_x000D_
});_x000D_
_x000D_
console.log(maximum); // 217
_x000D_
_x000D_
_x000D_

How to rotate portrait/landscape Android emulator?

See the Android documentation on controlling the emulator; it's Ctrl + F11 / Ctrl + F12.

On ThinkPad running Ubuntu, you may try CTRL + Left Arrow Key or Right Arrow Key

Git on Bitbucket: Always asked for password, even after uploading my public SSH key

The following assumes command-line access via iTerm / Terminal to bitbucket.

For MacOS Sierra 10.12.5, my system manifested an equivalent problem - asking for my SSH passphrase on each connection to bitbucket.

The issue has to do with OpenSSH updates in macOS 10.12.2, which are described here in Technical Note TN2449.

You very well might want to tailor your solution, but the following will work when added to your ~/.ssh/config file:

Host *
    UseKeychain yes

For more information on ssh configs, take a look at the man pages for ssh_config:

% man ssh_config

One other thing: there is a good write-up on superuser here that discusses this problem and various solutions depending on your needs and setup.

How can I enable the Windows Server Task Scheduler History recording?

The adjustment in the Task Scheduler app actually just controls the enabled state of a certain event log, so you can equivalently adjust the Task Scheduler "history" mode via the Windows command line:

wevtutil set-log Microsoft-Windows-TaskScheduler/Operational /enabled:true

To check the current state:

wevtutil get-log Microsoft-Windows-TaskScheduler/Operational

For the keystroke-averse, here are the slightly abbreviated versions of the above:

wevtutil sl Microsoft-Windows-TaskScheduler/Operational /e:true
wevtutil gl Microsoft-Windows-TaskScheduler/Operational

How to compare character ignoring case in primitive types

This is how the JDK does it (adapted from OpenJDK 8, String.java/regionMatches):

static boolean charactersEqualIgnoringCase(char c1, char c2) {
  if (c1 == c2) return true;

  // If characters don't match but case may be ignored,
  // try converting both characters to uppercase.
  char u1 = Character.toUpperCase(c1);
  char u2 = Character.toUpperCase(c2);
  if (u1 == u2) return true;

  // Unfortunately, conversion to uppercase does not work properly
  // for the Georgian alphabet, which has strange rules about case
  // conversion.  So we need to make one last check before
  // exiting.
  return Character.toLowerCase(u1) == Character.toLowerCase(u2);
}

I suppose that works for Turkish too.

Multiple Updates in MySQL

Yes ..it is possible using INSERT ON DUPLICATE KEY UPDATE sql statement.. syntax: INSERT INTO table_name (a,b,c) VALUES (1,2,3),(4,5,6) ON DUPLICATE KEY UPDATE a=VALUES(a),b=VALUES(b),c=VALUES(c)

Angular 4/5/6 Global Variables

You can use the Window object and access it everwhere. example window.defaultTitle = "my title"; then you can access window.defaultTitle without importing anything.

Error: Tablespace for table xxx exists. Please DISCARD the tablespace before IMPORT

Please DISCARD the tablespace before IMPORT

I got same issue solution is below

  1. First you have to drop your database name. if your database is not deleting you have flow me. For Windows system your directory will be C:/xampp/mysql/data/yourdabasefolder remove "yourdabasefolder"

  2. Again you have to create new database and import your old sql file. It will be work

Thanks

Postgres manually alter sequence

this worked for me:

SELECT pg_catalog.setval('public.hibernate_sequence', 3, true);

How to add a second css class with a conditional value in razor MVC 4

You can use String.Format function to add second class based on condition:

<div class="@String.Format("details {0}", Details.Count > 0 ? "show" : "hide")">

Best way to simulate "group by" from bash?

I'd have done it like this:

perl -e 'while (<>) {chop; $h{$_}++;} for $k (keys %h) {print "$k $h{$k}\n";}' ip_addresses

but uniq might work for you.

Tomcat 7.0.43 "INFO: Error parsing HTTP request header"

I tried all of the above, nothing worked for me. Then I changed tomcat port numbers both HTTP/1.1 and Tomcat admin port and it got solved.

I see other solutions above worked for the people but it is worth to try this one if any of the above doesn't work.

Thanks everyone!

jQuery DatePicker with today as maxDate

$(".datepicker").datepicker({maxDate: '0'});

This will set the maxDate to +0 days from the current date (i.e. today). See:

http://api.jqueryui.com/datepicker/#option-maxDate

How to repeat a string a variable number of times in C++?

Use one of the forms of string::insert:

std::string str("lolcat");
str.insert(0, 5, '.');

This will insert "....." (five dots) at the start of the string (position 0).

How to programmatically set the Image source

{yourImageName.Source = new BitmapImage(new Uri("ms-appx:///Assets/LOGO.png"));}

LOGO refers to your image

Hoping to help anyone. :)

When should the xlsm or xlsb formats be used?

One could think that xlsb has only advantages over xlsm. The fact that xlsm is XML-based and xlsb is binary is that when workbook corruption occurs, you have better chances to repair a xlsm than a xlsb.

Open a Web Page in a Windows Batch FIle

You can use the start command to do much the same thing as ShellExecute. For example

 start "" http://www.stackoverflow.com

This will launch whatever browser is the default browser, so won't necessarily launch Internet Explorer.

Git: How configure KDiff3 as merge tool and diff tool

I needed to add the command line parameters or KDiff3 would only open without files and prompt me for base, local and remote. I used the version supplied with TortoiseHg.

Additionally, I needed to resort to the good old DOS 8.3 file names.

[merge]
    tool = kdiff3

[mergetool "kdiff3"]
    cmd = /c/Progra~1/TortoiseHg/lib/kdiff3.exe $BASE $LOCAL $REMOTE -o $MERGED

However, it works correctly now.

Is there a reason for C#'s reuse of the variable in a foreach?

Having been bitten by this, I have a habit of including locally defined variables in the innermost scope which I use to transfer to any closure. In your example:

foreach (var s in strings)
    query = query.Where(i => i.Prop == s); // access to modified closure

I do:

foreach (var s in strings)
{
    string search = s;
    query = query.Where(i => i.Prop == search); // New definition ensures unique per iteration.
}        

Once you have that habit, you can avoid it in the very rare case you actually intended to bind to the outer scopes. To be honest, I don't think I have ever done so.

How to import Swagger APIs into Postman?

I work on PHP and have used Swagger 2.0 to document the APIs. The Swagger Document is created on the fly (at least that is what I use in PHP). The document is generated in the JSON format.

Sample document

{
    "swagger": "2.0",
    "info": {
    "title": "Company Admin Panel",
        "description": "Converting the Magento code into core PHP and RESTful APIs for increasing the performance of the website.",
        "contact": {
        "email": "[email protected]"
        },
        "version": "1.0.0"
    },
    "host": "localhost/cv_admin/api",
    "schemes": [
    "http"
],
    "paths": {
    "/getCustomerByEmail.php": {
        "post": {
            "summary": "List the details of customer by the email.",
                "consumes": [
                "string",
                "application/json",
                "application/x-www-form-urlencoded"
            ],
                "produces": [
                "application/json"
            ],
                "parameters": [
                    {
                        "name": "email",
                        "in": "body",
                        "description": "Customer email to ge the data",
                        "required": true,
                        "schema": {
                        "properties": {
                            "id": {
                                "properties": {
                                    "abc": {
                                        "properties": {
                                            "inner_abc": {
                                                "type": "number",
                                                    "default": 1,
                                                    "example": 123
                                                }
                                            },
                                            "type": "object"
                                        },
                                        "xyz": {
                                        "type": "string",
                                            "default": "xyz default value",
                                            "example": "xyz example value"
                                        }
                                    },
                                    "type": "object"
                                }
                            }
                        }
                    }
                ],
                "responses": {
                "200": {
                    "description": "Details of the customer"
                    },
                    "400": {
                    "description": "Email required"
                    },
                    "404": {
                    "description": "Customer does not exist"
                    },
                    "default": {
                    "description": "an \"unexpected\" error"
                    }
                }
            }
        },
        "/getCustomerById.php": {
        "get": {
            "summary": "List the details of customer by the ID",
                "parameters": [
                    {
                        "name": "id",
                        "in": "query",
                        "description": "Customer ID to get the data",
                        "required": true,
                        "type": "integer"
                    }
                ],
                "responses": {
                "200": {
                    "description": "Details of the customer"
                    },
                    "400": {
                    "description": "ID required"
                    },
                    "404": {
                    "description": "Customer does not exist"
                    },
                    "default": {
                    "description": "an \"unexpected\" error"
                    }
                }
            }
        },
        "/getShipmentById.php": {
        "get": {
            "summary": "List the details of shipment by the ID",
                "parameters": [
                    {
                        "name": "id",
                        "in": "query",
                        "description": "Shipment ID to get the data",
                        "required": true,
                        "type": "integer"
                    }
                ],
                "responses": {
                "200": {
                    "description": "Details of the shipment"
                    },
                    "404": {
                    "description": "Shipment does not exist"
                    },
                    "400": {
                    "description": "ID required"
                    },
                    "default": {
                    "description": "an \"unexpected\" error"
                    }
                }
            }
        }
    },
    "definitions": {

    }
}

This can be imported into Postman as follow.

  1. Click on the 'Import' button in the top left corner of Postman UI.
  2. You will see multiple options to import the API doc. Click on the 'Paste Raw Text'.
  3. Paste the JSON format in the text area and click import.
  4. You will see all your APIs as 'Postman Collection' and can use it from the Postman.

Importing the JSON into Postman

Imported APIs

You can also use 'Import From Link'. Here paste the URL which generates the JSON format of the APIs from the Swagger or any other API Document tool.

This is my Document (JSON) generation file. It's in PHP. I have no idea of JAVA along with Swagger.

<?php
require("vendor/autoload.php");
$swagger = \Swagger\scan('path_of_the_directory_to_scan');
header('Content-Type: application/json');
echo $swagger;

awk without printing newline

If Perl is an option, here is a solution using fedorqui's example:

seq 5 | perl -ne 'chomp; print "$_ "; END{print "\n"}'

Explanation:
chomp removes the newline
print "$_ " prints each line, appending a space
the END{} block is used to print a newline

output: 1 2 3 4 5

Fixing slow initial load for IIS

A good option to ping the site on a schedule is to use Microsoft Flow, which is free for up to 750 "runs" per month. It is very easy to create a Flow that hits your site every hour to keep it warm. You can even work around their limit of 750 by creating a single flow with delays separating multiple hits of your site.

https://flow.microsoft.com

how to get current location in google map android

package com.example.sandeep.googlemapsample;

import android.content.pm.PackageManager;
import android.location.Location;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback,
        GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener,
        GoogleMap.OnMarkerDragListener,
        GoogleMap.OnMapLongClickListener,
        GoogleMap.OnMarkerClickListener,
        View.OnClickListener {

    private static final String TAG = "MapsActivity";
    private GoogleMap mMap;
    private double longitude;
    private double latitude;
    private GoogleApiClient googleApiClient;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);

        // Obtain the SupportMapFragment and get notified when the map is ready to be used.
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);

        //Initializing googleApiClient
        googleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }


    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
       // googleMapOptions.mapType(googleMap.MAP_TYPE_HYBRID)
                    //    .compassEnabled(true);

        // Add a marker in Sydney and move the camera
        LatLng india = new LatLng(-34, 151);
        mMap.addMarker(new MarkerOptions().position(india).title("Marker in India"));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(india));
        mMap.setOnMarkerDragListener(this);
        mMap.setOnMapLongClickListener(this);
    }

    //Getting current location
    private void getCurrentLocation() {
        mMap.clear();
        if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            // TODO: Consider calling
            //    ActivityCompat#requestPermissions
            // here to request the missing permissions, and then overriding
            //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
            //                                          int[] grantResults)
            // to handle the case where the user grants the permission. See the documentation
            // for ActivityCompat#requestPermissions for more details.
            return;
        }
        Location location = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);
        if (location != null) {
            //Getting longitude and latitude
            longitude = location.getLongitude();
            latitude = location.getLatitude();

            //moving the map to location
            moveMap();
        }
    }

    private void moveMap() {
        /**
         * Creating the latlng object to store lat, long coordinates
         * adding marker to map
         * move the camera with animation
         */
        LatLng latLng = new LatLng(latitude, longitude);
        mMap.addMarker(new MarkerOptions()
                .position(latLng)
                .draggable(true)
                .title("Marker in India"));

        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
        mMap.animateCamera(CameraUpdateFactory.zoomTo(15));
        mMap.getUiSettings().setZoomControlsEnabled(true);


    }

    @Override
    public void onClick(View view) {
        Log.v(TAG,"view click event");
    }

    @Override
    public void onConnected(@Nullable Bundle bundle) {
        getCurrentLocation();
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

    }

    @Override
    public void onMapLongClick(LatLng latLng) {
        // mMap.clear();
        mMap.addMarker(new MarkerOptions().position(latLng).draggable(true));
    }

    @Override
    public void onMarkerDragStart(Marker marker) {
        Toast.makeText(MapsActivity.this, "onMarkerDragStart", Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onMarkerDrag(Marker marker) {
        Toast.makeText(MapsActivity.this, "onMarkerDrag", Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onMarkerDragEnd(Marker marker) {
        // getting the Co-ordinates
        latitude = marker.getPosition().latitude;
        longitude = marker.getPosition().longitude;

        //move to current position
        moveMap();
    }

    @Override
    protected void onStart() {
        googleApiClient.connect();
        super.onStart();
    }

    @Override
    protected void onStop() {
        googleApiClient.disconnect();
        super.onStop();
    }


    @Override
    public boolean onMarkerClick(Marker marker) {
        Toast.makeText(MapsActivity.this, "onMarkerClick", Toast.LENGTH_SHORT).show();
        return true;
    }

}

What is content-type and datatype in an AJAX request?

See http://api.jquery.com/jQuery.ajax/, there's mention of datatype and contentType there.

They are both used in the request to the server so the server knows what kind of data to receive/send.

Javascript get the text value of a column from a particular row of an html table

in case if your table has tbody

let tbl = document.getElementById("tbl").getElementsByTagName('tbody')[0];
console.log(tbl.rows[0].cells[0].innerHTML)

Is null check needed before calling instanceof?

No, it's not. instanceof would return false if its first operand is null.

Extracting Ajax return data in jQuery

You can use .filter on a jQuery object that was created from the response:

success: function(data){
    //Create jQuery object from the response HTML.
    var $response=$(data);

    //Query the jQuery object for the values
    var oneval = $response.filter('#one').text();
    var subval = $response.filter('#sub').text();
}

json.decoder.JSONDecodeError: Extra data: line 2 column 1 (char 190)

You have two records in your json file, and json.loads() is not able to decode more than one. You need to do it record by record.

See Python json.loads shows ValueError: Extra data

OR you need to reformat your json to contain an array:

{
    "foo" : [
       {"name": "XYZ", "address": "54.7168,94.0215", "country_of_residence": "PQR", "countries": "LMN;PQRST", "date": "28-AUG-2008", "type": null},
       {"name": "OLMS", "address": null, "country_of_residence": null, "countries": "Not identified;No", "date": "23-FEB-2017", "type": null}
    ]
}

would be acceptable again. But there cannot be several top level objects.