Programs & Examples On #Nodename

Kubernetes Pod fails with CrashLoopBackOff

I faced similar issue "CrashLoopBackOff" when I debugged getting pods and logs of pod. Found out that my command arguments are wrong

get original element from ng-click

You need $event.currentTarget instead of $event.target.

How to fix getImageData() error The canvas has been tainted by cross-origin data?

As matt burns says in his answer, you may need to enable CORS on the server where the problem images are hosted.

If the server is Apache, this can be done by adding the following snippet (from here) to either your VirtualHost config or an .htaccess file:

<IfModule mod_setenvif.c>
    <IfModule mod_headers.c>
        <FilesMatch "\.(cur|gif|ico|jpe?g|png|svgz?|webp)$">
            SetEnvIf Origin ":" IS_CORS
            Header set Access-Control-Allow-Origin "*" env=IS_CORS
        </FilesMatch>
    </IfModule>
</IfModule>

...if adding it to a VirtualHost, you'll probably need to reload Apache's config too (eg. sudo service apache2 reload if Apache's running on a Linux server)

ssh: Could not resolve hostname [hostname]: nodename nor servname provided, or not known

I had the same issue, which I was able to resolve by adding a .local to the host name, ala ssh [email protected]

Console.log not working at all

I just had a same issue of none of my console message showing. It was simply because I was using the new Edge (Chromium based) browser on Windows 10. It does not show my console messages whereas Chrome does. I guessed it was an issue with Edge because I had another odd issue with Edge because it treated strings with single quotes and double quotes differently.

IntelliJ, can't start simple web application: Unable to ping server at localhost:1099

Setting project's SDK in IntelliJ (File > Project Structure > Project:Project SDK) worked for me

Using curl POST with variables defined in bash script functions

You don't need to pass the quotes enclosing the custom headers to curl. Also, your variables in the middle of the data argument should be quoted.

First, write a function that generates the post data of your script. This saves you from all sort of headaches concerning shell quoting and makes it easier to read an maintain the script than feeding the post data on curl's invocation line as in your attempt:

generate_post_data()
{
  cat <<EOF
{
  "account": {
    "email": "$email",
    "screenName": "$screenName",
    "type": "$theType",
    "passwordSettings": {
      "password": "$password",
      "passwordConfirm": "$password"
    }
  },
  "firstName": "$firstName",
  "lastName": "$lastName",
  "middleName": "$middleName",
  "locale": "$locale",
  "registrationSiteId": "$registrationSiteId",
  "receiveEmail": "$receiveEmail",
  "dateOfBirth": "$dob",
  "mobileNumber": "$mobileNumber",
  "gender": "$gender",
  "fuelActivationDate": "$fuelActivationDate",
  "postalCode": "$postalCode",
  "country": "$country",
  "city": "$city",
  "state": "$state",
  "bio": "$bio",
  "jpFirstNameKana": "$jpFirstNameKana",
  "jpLastNameKana": "$jpLastNameKana",
  "height": "$height",
  "weight": "$weight",
  "distanceUnit": "MILES",
  "weightUnit": "POUNDS",
  "heightUnit": "FT/INCHES"
}
EOF
}

It is then easy to use that function in the invocation of curl:

curl -i \
-H "Accept: application/json" \
-H "Content-Type:application/json" \
-X POST --data "$(generate_post_data)" "https://xxx:[email protected]/xxxxx/xxxx/xxxx"

This said, here are a few clarifications about shell quoting rules:

The double quotes in the -H arguments (as in -H "foo bar") tell bash to keep what's inside as a single argument (even if it contains spaces).

The single quotes in the --data argument (as in --data 'foo bar') do the same, except they pass all text verbatim (including double quote characters and the dollar sign).

To insert a variable in the middle of a single quoted text, you have to end the single quote, then concatenate with the double quoted variable, and re-open the single quote to continue the text: 'foo bar'"$variable"'more foo'.

Loop through all elements in XML using NodeList

Here is another way to loop through XML elements using JDOM.

        List<Element> nodeNodes = inputNode.getChildren();
        if (nodeNodes != null) {
            for (Element nodeNode : nodeNodes) {
                List<Element> elements = nodeNode.getChildren(elementName);
                if (elements != null) {
                    elements.size();
                    nodeNodes.removeAll(elements);
                }
            }

jQuery validate Uncaught TypeError: Cannot read property 'nodeName' of null

I found this answer when I was getting a similar error for nodeName after upgrading to Bootstrap 4. The issue was that the tabs didn't have the nav and nav-tab classes; adding those to the <ul> element fixed the issue.

How to create table using select query in SQL Server?

An example statement that uses a sub-select :

select * into MyNewTable
from
(
select 
  * 
from 
[SomeOtherTablename]
where 
  EventStartDatetime >= '01/JAN/2018' 
)
) mysourcedata
;

note that the sub query must be given a name .. any name .. e.g. above example gives the subquery a name of mysourcedata. Without this a syntax error is issued in SQL*server 2012.

The database should reply with a message like: (9999 row(s) affected)

What properties can I use with event.target?

event.target returns the node that was targeted by the function. This means you can do anything you would do with any other node like one you'd get from document.getElementById

How to inspect Javascript Objects

var str = "";
for(var k in obj)
    if (obj.hasOwnProperty(k)) //omit this test if you want to see built-in properties
        str += k + " = " + obj[k] + "\n";
alert(str);

Get list of data-* attributes using javascript / jQuery

Have a look here:

If the browser also supports the HTML5 JavaScript API, you should be able to get the data with:

var attributes = element.dataset

or

var cat = element.dataset.cat

Oh, but I also read:

Unfortunately, the new dataset property has not yet been implemented in any browser, so in the meantime it’s best to use getAttribute and setAttribute as demonstrated earlier.

It is from May 2010.


If you use jQuery anyway, you might want to have a look at the customdata plugin. I have no experience with it though.

getaddrinfo: nodename nor servname provided, or not known

The error occurs when the DNS resolution fails. Check if you can wget (or curl) the api url from the command line. Changing the DNS server and testing it might help.

How to call a MySQL stored procedure from within PHP code?

This is my solution with prepared statements and stored procedure is returning several rows not only one value.

<?php

require 'config.php';
header('Content-type:application/json');
$connection->set_charset('utf8');

$mIds = $_GET['ids'];

$stmt = $connection->prepare("CALL sp_takes_string_returns_table(?)");
$stmt->bind_param("s", $mIds);

$stmt->execute();

$result = $stmt->get_result();
$response = $result->fetch_all(MYSQLI_ASSOC);
echo json_encode($response);

$stmt->close();
$connection->close();

Executing <script> elements inserted with .innerHTML

@phidah... Here is a very interesting solution to your problem: http://24ways.org/2005/have-your-dom-and-script-it-too

So it would look like this instead:

<img src="empty.gif" onload="alert('test');this.parentNode.removeChild(this);" />

Getting XML Node text value with Java DOM

I use a very old java. Jdk 1.4.08 and I had the same issue. The Node class for me did not had the getTextContent() method. I had to use Node.getFirstChild().getNodeValue() instead of Node.getNodeValue() to get the value of the node. This fixed for me.

SQL select max(date) and corresponding value

Each MAX function is evaluated individually. So MAX(CompletedDate) will return the value of the latest CompletedDate column and MAX(Notes) will return the maximum (i.e. alphabeticaly highest) value.

You need to structure your query differently to get what you want. This question had actually already been asked and answered several times, so I won't repeat it:

How to find the record in a table that contains the maximum value?

Finding the record with maximum value in SQL

How can I send an email through the UNIX mailx command?

From the man page:

Sending mail

To send a message to one or more people, mailx can be invoked with arguments which are the names of people to whom the mail will be sent. The user is then expected to type in his message, followed by an ‘control-D’ at the beginning of a line.

In other words, mailx reads the content to send from standard input and can be redirected to like normal. E.g.:

ls -l $HOME | mailx -s "The content of my home directory" [email protected]

How to run Visual Studio post-build events for debug build only

You can pass the configuration name to the post-build script and check it in there to see if it should run.

Pass the configuration name with $(ConfigurationName).

Checking it is based on how you are implementing the post-build step -- it will be a command-line argument.

Printing out a number in assembly language?

Call WinAPI function (if u are developing win-application)

increase the java heap size permanently?

For Windows users, you can add a system environment variable named _JAVA_OPTIONS, and set the heap size values there. The JVM should be able to grab the virtual machine options from _JAVA_OPTIONS.

Archive the artifacts in Jenkins

Your understanding is correct, an artifact in the Jenkins sense is the result of a build - the intended output of the build process.

A common convention is to put the result of a build into a build, target or bin directory.

The Jenkins archiver can use globs (target/*.jar) to easily pick up the right file even if you have a unique name per build.

Laravel - Session store not set on request

in my case it was just to put return ; at the end of function where i have set session

Can I change the name of `nohup.out`?

As the file handlers points to i-nodes (which are stored independently from file names) on Linux/Unix systems You can rename the default nohup.out to any other filename any time after starting nohup something&. So also one could do the following:

$ nohup something&
$ mv nohup.out nohup2.out
$ nohup something2&

Now something adds lines to nohup2.out and something2 to nohup.out.

OpenCV - Saving images to a particular folder of choice

The solution provided by ebeneditos works perfectly.

But if you have cv2.imwrite() in several sections of a large code snippet and you want to change the path where the images get saved, you will have to change the path at every occurrence of cv2.imwrite() individually.

As Soltius stated, here is a better way. Declare a path and pass it as a string into cv2.imwrite()

import cv2
import os
img = cv2.imread('1.jpg', 1)
path = 'D:/OpenCV/Scripts/Images'
cv2.imwrite(os.path.join(path , 'waka.jpg'), img)
cv2.waitKey(0)

Now if you want to modify the path, you just have to change the path variable.

Edited based on solution provided by Kallz

@font-face src: local - How to use the local font if the user already has it?

I haven’t actually done anything with font-face, so take this with a pinch of salt, but I don’t think there’s any way for the browser to definitively tell if a given web font installed on a user’s machine or not.

The user could, for example, have a different font with the same name installed on their machine. The only way to definitively tell would be to compare the font files to see if they’re identical. And the browser couldn’t do that without downloading your web font first.

Does Firefox download the font when you actually use it in a font declaration? (e.g. h1 { font: 'DejaVu Serif';)?

Onclick event to remove default value in a text input field

In addition to placeholder="your text" you could also do onclick="this.value='';

So it would look something like:

<input name="Name" value="Enter Your Name" onclick="this.value='';>

Explode string by one or more spaces or tabs

@OP it doesn't matter, you can just split on a space with explode. Until you want to use those values, iterate over the exploded values and discard blanks.

$str = "A      B      C      D";
$s = explode(" ",$str);
foreach ($s as $a=>$b){    
    if ( trim($b) ) {
     print "using $b\n";
    }
}

MySQL "between" clause not inclusive?

The problem is that 2011-01-31 really is 2011-01-31 00:00:00. That is the beginning of the day. Everything during the day is not included.

PowerShell: Comparing dates

As Get-Date returns a DateTime object you are able to compare them directly. An example:

(get-date 2010-01-02) -lt (get-date 2010-01-01)

will return false.

R: invalid multibyte string

I figured out Leafpad to be an adequate and simple text-editor to view and save/convert in certain character sets - at least in the linux-world.

I used this to save the Latin-15 to UTF-8 and it worked.

What are pipe and tap methods in Angular tutorial?

You are right, the documentation lacks of those methods. However when I dug into rxjs repository, I found nice comments about tap (too long to paste here) and pipe operators:

  /**
   * Used to stitch together functional operators into a chain.
   * @method pipe
   * @return {Observable} the Observable result of all of the operators having
   * been called in the order they were passed in.
   *
   * @example
   *
   * import { map, filter, scan } from 'rxjs/operators';
   *
   * Rx.Observable.interval(1000)
   *   .pipe(
   *     filter(x => x % 2 === 0),
   *     map(x => x + x),
   *     scan((acc, x) => acc + x)
   *   )
   *   .subscribe(x => console.log(x))
   */

In brief:

Pipe: Used to stitch together functional operators into a chain. Before we could just do observable.filter().map().scan(), but since every RxJS operator is a standalone function rather than an Observable's method, we need pipe() to make a chain of those operators (see example above).

Tap: Can perform side effects with observed data but does not modify the stream in any way. Formerly called do(). You can think of it as if observable was an array over time, then tap() would be an equivalent to Array.forEach().

Where do I put image files, css, js, etc. in Codeigniter?

No, inside the views folder is not good.

Look: You must have 3 basic folders on your project:

system // This is CI framework there are not much reasons to touch this files

application //this is where your logic goes, the files that makes the application,

public // this must be your documentroot

For security reasons its better to keep your framework and the application outside your documentroot,(public_html, htdocs, public, www... etc)

Inside your public folder, you should put your public info, what the browsers can see, its common to find the folders: images, js, css; so your structure will be:

|- system/
|- application/
|---- models/
|---- views/
|---- controllers/
|- public/
|---- images/
|---- js/
|---- css/
|---- index.php
|---- .htaccess

PHP - warning - Undefined property: stdClass - fix?

Depending on whether you're looking for a member or method, you can use either of these two functions to see if a member/method exists in a particular object:

http://php.net/manual/en/function.method-exists.php

http://php.net/manual/en/function.property-exists.php

More generally if you want all of them:

http://php.net/manual/en/function.get-object-vars.php

How to get input text value on click in ReactJS

There are two ways to go about doing this.

  1. Create a state in the constructor that contains the text input. Attach an onChange event to the input box that updates state each time. Then onClick you could just alert the state object.

  2. handleClick: function() { alert(this.refs.myInput.value); },

A html space is showing as %2520 instead of %20

A bit of explaining as to what that %2520 is :

The common space character is encoded as %20 as you noted yourself. The % character is encoded as %25.

The way you get %2520 is when your url already has a %20 in it, and gets urlencoded again, which transforms the %20 to %2520.

Are you (or any framework you might be using) double encoding characters?

Edit: Expanding a bit on this, especially for LOCAL links. Assuming you want to link to the resource C:\my path\my file.html:

  • if you provide a local file path only, the browser is expected to encode and protect all characters given (in the above, you should give it with spaces as shown, since % is a valid filename character and as such it will be encoded) when converting to a proper URL (see next point).
  • if you provide a URL with the file:// protocol, you are basically stating that you have taken all precautions and encoded what needs encoding, the rest should be treated as special characters. In the above example, you should thus provide file:///c:/my%20path/my%20file.html. Aside from fixing slashes, clients should not encode characters here.

NOTES:

  • Slash direction - forward slashes / are used in URLs, reverse slashes \ in Windows paths, but most clients will work with both by converting them to the proper forward slash.
  • In addition, there are 3 slashes after the protocol name, since you are silently referring to the current machine instead of a remote host ( the full unabbreviated path would be file://localhost/c:/my%20path/my%file.html ), but again most clients will work without the host part (ie two slashes only) by assuming you mean the local machine and adding the third slash.

How to use Angular4 to set focus by element id

One of the answers in the question referred to by @Z.Bagley gave me the answer. I had to import Renderer2 from @angular/core into my component. Then:

const element = this.renderer.selectRootElement('#input1');

// setTimeout(() => element.focus, 0);
setTimeout(() => element.focus(), 0);

Thank you @MrBlaise for the solution!

Explain ggplot2 warning: "Removed k rows containing missing values"

I ran into this as well, but in the case where I wanted to avoid the extra error messages while keeping the range provided. An option is also to subset the data prior to setting the range, so that the range can be kept however you like without triggering warnings.

library(ggplot2)

range(mtcars$hp)
#> [1]  52 335

# Setting limits with scale_y_continous (or ylim) and subsetting accordingly
## avoid warning messages about removing data
ggplot(data= subset(mtcars, hp<=300 & hp >= 100), aes(mpg, hp)) + 
  geom_point() +
  scale_y_continuous(limits=c(100,300))

How can I change the Java Runtime Version on Windows (7)?

Once I updated my Java version to 8 as suggested by browser. However I had selected to uninstall previous Java 6 version I have been used for coding my projects. When I enter the command in "java -version" in cmd it showed 1.8 and I could not start eclipse IDE run on Java 1.6.

When I installed Java 8 update for the browser it had changed the "PATH" System variable appending "C:\ProgramData\Oracle\Java\javapath" to the beginning. Newly added path pointed to Java vesion 8. So I removed that path from "PATH" System variable and everything worked fine. :)

Cannot edit in read-only editor VS Code

The easiest way to fix this was to press (CTRL) and (,) in VS Code to open Settings.

After that, on the search bar search for code runner, then scroll down and search for Run In Terminal and check that box as highlighted in the below image:

Why avoid increment ("++") and decrement ("--") operators in JavaScript?

Is Fortran a C-like language? It has neither ++ nor --. Here is how you write a loop:

     integer i, n, sum

      sum = 0
      do 10 i = 1, n
         sum = sum + i
         write(*,*) 'i =', i
         write(*,*) 'sum =', sum
  10  continue

The index element i is incremented by the language rules each time through the loop. If you want to increment by something other than 1, count backwards by two for instance, the syntax is ...

      integer i

      do 20 i = 10, 1, -2
         write(*,*) 'i =', i
  20  continue

Is Python C-like? It uses range and list comprehensions and other syntaxes to bypass the need for incrementing an index:

print range(10,1,-2) # prints [10,8.6.4.2]
[x*x for x in range(1,10)] # returns [1,4,9,16 ... ]

So based on this rudimentary exploration of exactly two alternatives, language designers may avoid ++ and -- by anticipating use cases and providing an alternate syntax.

Are Fortran and Python notably less of a bug magnet than procedural languages which have ++ and --? I have no evidence.

I claim that Fortran and Python are C-like because I have never met someone fluent in C who could not with 90% accuracy guess correctly the intent of non-obfuscated Fortran or Python.

Trouble setting up git with my GitHub Account error: could not lock config file

A bit like in "Trouble setting up Tower with my GitHub Account - error: could not lock config file", check how that ~/.gitconfig file has been created.
Ie: with which rights associated to it?

Make also sure your $HOME variable is correctly set when you are executing the git config --global command.

PHP get dropdown value and text

Is there a reason you didn't just use this?

<select id="animal" name="animal">                      
  <option value="0">--Select Animal--</option>
  <option value="Cat">Cat</option>
  <option value="Dog">Dog</option>
  <option value="Cow">Cow</option>
</select>

if($_POST['submit'] && $_POST['submit'] != 0)
{
   $animal=$_POST['animal'];
}

How to create streams from string in Node.Js?

Heres a tidy solution in TypeScript:

import { Readable } from 'stream'

class ReadableString extends Readable {
    private sent = false

    constructor(
        private str: string
    ) {
        super();
    }

    _read() {
        if (!this.sent) {
            this.push(Buffer.from(this.str));
            this.sent = true
        }
        else {
            this.push(null)
        }
    }
}

const stringStream = new ReadableString('string to be streamed...')

TypeError: document.getElementbyId is not a function

JavaScript is case-sensitive. The b in getElementbyId should be capitalized.

var content = document.getElementById("edit").innerHTML;

Compiling a java program into an executable

I usually use a bat script for that. Here's what I typically use:

@echo off
set d=%~dp0
java -Xmx400m -cp "%d%myapp.jar;%d%libs/mylib.jar" my.main.Class %*

The %~dp0 extract the directory where the .bat is located. This allows the bat to find the locations of the jars without requiring any special environment variables nor the setting of the PATH variable.

EDIT: Added quotes to the classpath. Otherwise, as Joey said, "fun things can happen with spaces"

Eclipse can't find / load main class

I had the same problem, this is my solution:

  1. I manually deleted the bin folder of the project
  2. Then I refreshed the project which recompiled the whole project and created a new bin with all .class files

I did it because when I performed Clean(project->clean) my .class files were not getting deleted. the above solution works for me hope its useful to others.

Vue.js data-bind style backgroundImage not working

I tried @david answer, and it didn't fix my issue. after a lot of hassle, I made a method and return the image with style string.

HTML Code

<div v-for="slide in loadSliderImages" :key="slide.id">
    <div v-else :style="bannerBgImage(slide.banner)"></div>
</div>

Method

bannerBgImage(image){
    return 'background-image: url("' + image + '")';
},

Export MySQL data to Excel in PHP

Try this code. It's definitly working.

<?php
// Connection 

$conn=mysql_connect('localhost','root','');
$db=mysql_select_db('excel',$conn);

$filename = "Webinfopen.xls"; // File Name
// Download file
header("Content-Disposition: attachment; filename=\"$filename\"");
header("Content-Type: application/vnd.ms-excel");
$user_query = mysql_query('select name,work from info');
// Write data to file
$flag = false;
while ($row = mysql_fetch_assoc($user_query)) {
    if (!$flag) {
        // display field/column names as first row
        echo implode("\t", array_keys($row)) . "\r\n";
        $flag = true;
    }
    echo implode("\t", array_values($row)) . "\r\n";
}
?>

How to get the name of a class without the package?

Class.getSimpleName()

Returns the simple name of the underlying class as given in the source code. Returns an empty string if the underlying class is anonymous.

The simple name of an array is the simple name of the component type with "[]" appended. In particular the simple name of an array whose component type is anonymous is "[]".

It is actually stripping the package information from the name, but this is hidden from you.

How to order a data frame by one descending and one ascending column?

I use rank:

rum <- read.table(textConnection("P1  P2  P3  T1  T2  T3  I1  I2
2   3   5   52  43  61  6   b
6   4   3   72  NA  59  1   a
1   5   6   55  48  60  6   f
2   4   4   65  64  58  2   b
1   5   6   55  48  60  6   c"), header = TRUE)

> rum[order(rum$I1, -rank(rum$I2), decreasing = TRUE), ]
  P1 P2 P3 T1 T2 T3 I1 I2
1  2  3  5 52 43 61  6  b
5  1  5  6 55 48 60  6  c
3  1  5  6 55 48 60  6  f
4  2  4  4 65 64 58  2  b
2  6  4  3 72 NA 59  1  a

Now() function with time trim

Dates in VBA are just floating point numbers, where the integer part represents the date and the fraction part represents the time. So in addition to using the Date function as tlayton says (to get the current date) you can also cast a date value to a integer to get the date-part from an arbitrary date: Int(myDateValue).

How to install OpenJDK 11 on Windows?

AdoptOpenJDK is a new website hosted by the java community. You can find .msi installers for OpenJDK 8 through 14 there, which will perform all the things listed in the question (Unpacking, registry keys, PATH variable updating (and JAVA_HOME), uninstaller...).

SignalR - Sending a message to a specific user using (IUserIdProvider) *NEW 2.0.0*

SignalR provides ConnectionId for each connection. To find which connection belongs to whom (the user), we need to create a mapping between the connection and the user. This depends on how you identify a user in your application.

In SignalR 2.0, this is done by using the inbuilt IPrincipal.Identity.Name, which is the logged in user identifier as set during the ASP.NET authentication.

However, you may need to map the connection with the user using a different identifier instead of using the Identity.Name. For this purpose this new provider can be used with your custom implementation for mapping user with the connection.

Example of Mapping SignalR Users to Connections using IUserIdProvider

Lets assume our application uses a userId to identify each user. Now, we need to send message to a specific user. We have userId and message, but SignalR must also know the mapping between our userId and the connection.

To achieve this, first we need to create a new class which implements IUserIdProvider:

public class CustomUserIdProvider : IUserIdProvider
{
     public string GetUserId(IRequest request)
    {
        // your logic to fetch a user identifier goes here.

        // for example:

        var userId = MyCustomUserClass.FindUserId(request.User.Identity.Name);
        return userId.ToString();
    }
}

The second step is to tell SignalR to use our CustomUserIdProvider instead of the default implementation. This can be done in the Startup.cs while initializing the hub configuration:

public class Startup
{
    public void Configuration(IAppBuilder app)
    {
        var idProvider = new CustomUserIdProvider();

        GlobalHost.DependencyResolver.Register(typeof(IUserIdProvider), () => idProvider);          

        // Any connection or hub wire up and configuration should go here
        app.MapSignalR();
    }
}

Now, you can send message to a specific user using his userId as mentioned in the documentation, like:

public class MyHub : Hub
{
   public void Send(string userId, string message)
   {
      Clients.User(userId).send(message);
   }
}

Hope this helps.

Best way to move files between S3 buckets?

Update

As pointed out by alberge (+1), nowadays the excellent AWS Command Line Interface provides the most versatile approach for interacting with (almost) all things AWS - it meanwhile covers most services' APIs and also features higher level S3 commands for dealing with your use case specifically, see the AWS CLI reference for S3:

  • sync - Syncs directories and S3 prefixes. Your use case is covered by Example 2 (more fine grained usage with --exclude, --include and prefix handling etc. is also available):

    The following sync command syncs objects under a specified prefix and bucket to objects under another specified prefix and bucket by copying s3 objects. [...]

    aws s3 sync s3://from_my_bucket s3://to_my_other_bucket
    

For completeness, I'll mention that the lower level S3 commands are also still available via the s3api sub command, which would allow to directly translate any SDK based solution to the AWS CLI before adopting its higher level functionality eventually.


Initial Answer

Moving files between S3 buckets can be achieved by means of the PUT Object - Copy API (followed by DELETE Object):

This implementation of the PUT operation creates a copy of an object that is already stored in Amazon S3. A PUT copy operation is the same as performing a GET and then a PUT. Adding the request header, x-amz-copy-source, makes the PUT operation copy the source object into the destination bucket. Source

There are respective samples for all existing AWS SDKs available, see Copying Objects in a Single Operation. Naturally, a scripting based solution would be the obvious first choice here, so Copy an Object Using the AWS SDK for Ruby might be a good starting point; if you prefer Python instead, the same can be achieved via boto as well of course, see method copy_key() within boto's S3 API documentation.

PUT Object only copies files, so you'll need to explicitly delete a file via DELETE Object still after a successful copy operation, but that will be just another few lines once the overall script handling the bucket and file names is in place (there are respective examples as well, see e.g. Deleting One Object Per Request).

Counting DISTINCT over multiple columns

It works for me. In oracle:

SELECT SUM(DECODE(COUNT(*),1,1,1))
FROM DocumentOutputItems GROUP BY DocumentId, DocumentSessionId;

In jpql:

SELECT SUM(CASE WHEN COUNT(i)=1 THEN 1 ELSE 1 END)
FROM DocumentOutputItems i GROUP BY i.DocumentId, i.DocumentSessionId;

How to check for an undefined or null variable in JavaScript?

Testing nullity (if (value == null)) or non-nullity (if (value != null)) is less verbose than testing the definition status of a variable.

Moreover, testing if (value) (or if( obj.property)) to ensure the existence of your variable (or object property) fails if it is defined with a boolean false value. Caveat emptor :)

php check if array contains all array values from another array

How about this:

function array_keys_exist($searchForKeys = array(), $searchableArray) {
    $searchableArrayKeys = array_keys($searchableArray);

    return count(array_intersect($searchForKeys, $searchableArrayKeys)) == count($searchForKeys); 
}

Comparing two hashmaps for equal values and same key sets?

Simply use :

mapA.equals(mapB);

Compares the specified object with this map for equality. Returns true if the given object is also a map and the two maps represent the same mappings

How to change 1 char in the string?

Strings are immutable, meaning you can't change a character. Instead, you create new strings.

What you are asking can be done several ways. The most appropriate solution will vary depending on the nature of the changes you are making to the original string. Are you changing only one character? Do you need to insert/delete/append?

Here are a couple ways to create a new string from an existing string, but having a different first character:

str = 'M' + str.Remove(0, 1);

str = 'M' + str.Substring(1);

Above, the new string is assigned to the original variable, str.

I'd like to add that the answers from others demonstrating StringBuilder are also very appropriate. I wouldn't instantiate a StringBuilder to change one character, but if many changes are needed StringBuilder is a better solution than my examples which create a temporary new string in the process. StringBuilder provides a mutable object that allows many changes and/or append operations. Once you are done making changes, an immutable string is created from the StringBuilder with the .ToString() method. You can continue to make changes on the StringBuilder object and create more new strings, as needed, using .ToString().

What are .a and .so files?

.a files are usually libraries which get statically linked (or more accurately archives), and
.so are dynamically linked libraries.

To do a port you will need the source code that was compiled to make them, or equivalent files on your AIX machine.

Execute PHP function with onclick

In javascript, make an ajax function,

function myAjax() {
      $.ajax({
           type: "POST",
           url: 'your_url/ajax.php',
           data:{action:'call_this'},
           success:function(html) {
             alert(html);
           }

      });
 }

Then call from html,

<a href="" onclick="myAjax()" class="deletebtn">Delete</a>

And in your ajax.php,

if($_POST['action'] == 'call_this') {
  // call removeday() here
}

assigning column names to a pandas series

You can create a dict and pass this as the data param to the dataframe constructor:

In [235]:

df = pd.DataFrame({'Gene':s.index, 'count':s.values})
df
Out[235]:
   Gene  count
0  Ezh2      2
1  Hmgb      7
2  Irf1      1

Alternatively you can create a df from the series, you need to call reset_index as the index will be used and then rename the columns:

In [237]:

df = pd.DataFrame(s).reset_index()
df.columns = ['Gene', 'count']
df
Out[237]:
   Gene  count
0  Ezh2      2
1  Hmgb      7
2  Irf1      1

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.

What is Parse/parsing?

Parsing is just process of analyse the string of character and find the tokens from that string and parser is a component of interpreter and compiler.It uses lexical analysis and then syntactic analysis.It parse it and then compile this code after this whole process of compilation.

ImportError: No module named BeautifulSoup

Try This, Mine worked this way. To get any data of tag just replace the "a" with the tag you want.

from bs4 import BeautifulSoup as bs
import urllib

url="http://currentaffairs.gktoday.in/month/current-affairs-january-2015"

soup = bs(urllib.urlopen(url))
for link in soup.findAll('a'):
        print link.string

Verify External Script Is Loaded

Another way to check an external script is loaded or not, you can use data function of jquery and store a validation flag. Example as :

if(!$("body").data("google-map"))
    {
        console.log("no js");

        $.getScript("https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false&callback=initilize",function(){
            $("body").data("google-map",true);

            },function(){
                alert("error while loading script");
            });
        }
    }
    else
    {
        console.log("js already loaded");
    }

add image to uitableview cell

cell.imageView.image = [UIImage imageNamed:@"image.png"];

UPDATE: Like Steven Fisher said, this should only work for cells with style UITableViewCellStyleDefault which is the default style. For other styles, you'd need to add a UIImageView to the cell's contentView.

How to find the size of integer array

If the array is a global, static, or automatic variable (int array[10];), then sizeof(array)/sizeof(array[0]) works.

If it is a dynamically allocated array (int* array = malloc(sizeof(int)*10);) or passed as a function argument (void f(int array[])), then you cannot find its size at run-time. You will have to store the size somewhere.
Note that sizeof(array)/sizeof(array[0]) compiles just fine even for the second case, but it will silently produce the wrong result.

How to read data from java properties file using Spring Boot

We can read properties file in spring boot using 3 way

1. Read value from application.properties Using @Value

map key as

public class EmailService {

 @Value("${email.username}")
 private String username;

}

2. Read value from application.properties Using @ConfigurationProperties

In this we will map prefix of key using ConfigurationProperties and key name is same as field of class

  @Component
   @ConfigurationProperties("email")
    public class EmailConfig {

        private String   username;
    }

3. Read application.properties Using using Environment object

public class EmailController {

@Autowired
private Environment env;

@GetMapping("/sendmail")
public void sendMail(){     
    System.out.println("reading value from application properties file  using Environment ");
    System.out.println("username ="+ env.getProperty("email.username"));
    System.out.println("pwd ="+ env.getProperty("email.pwd"));
}

Reference : how to read value from application.properties in spring boot

Could not find module "@angular-devkit/build-angular"

Node Package Manager does not install devDependencies, whenever you run npm install. Rather what it does is that it installs all the dependencies. So you just have to copy the contents of DevDependencies to Dependencies in package.json, which will force the manager to install those libraries. After copying all the DevDependencies to Dependencies, just run the command npm install, then proceed with ng serve and BOOM its up and running!!! I hope it helps. Thank you

require is not defined? Node.js

This can now also happen in Node.js as of version 14.

It happens when you declare your package type as module in your package.json. If you do this, certain CommonJS variables can't be used, including require.

To fix this, remove "type": "module" from your package.json and make sure you don't have any files ending with .mjs.

jQuery changing css class to div

Yep, easily.

$("#mydiv").attr("class", "second");

Inserting a tab character into text using C#

Hazar is right with his \t. Here's the full list of escape characters for C#:

\' for a single quote.

\" for a double quote.

\\ for a backslash.

\0 for a null character.

\a for an alert character.

\b for a backspace.

\f for a form feed.

\n for a new line.

\r for a carriage return.

\t for a horizontal tab.

\v for a vertical tab.

\uxxxx for a unicode character hex value (e.g. \u0020).

\x is the same as \u, but you don't need leading zeroes (e.g. \x20).

\Uxxxxxxxx for a unicode character hex value (longer form needed for generating surrogates).

Multiple separate IF conditions in SQL Server

IF you are checking one variable against multiple condition then you would use something like this Here the block of code where the condition is true will be executed and other blocks will be ignored.

IF(@Var1 Condition1)
     BEGIN
      /*Your Code Goes here*/
     END

ELSE IF(@Var1 Condition2)
      BEGIN
        /*Your Code Goes here*/ 
      END 

    ELSE      --<--- Default Task if none of the above is true
     BEGIN
       /*Your Code Goes here*/
     END

If you are checking conditions against multiple variables then you would have to go for multiple IF Statements, Each block of code will be executed independently from other blocks.

IF(@Var1 Condition1)
 BEGIN
   /*Your Code Goes here*/
 END


IF(@Var2 Condition1)
 BEGIN
   /*Your Code Goes here*/
 END


IF(@Var3 Condition1)
 BEGIN
   /*Your Code Goes here*/
 END

After every IF statement if there are more than one statement being executed you MUST put them in BEGIN..END Block. Anyway it is always best practice to use BEGIN..END blocks

Update

Found something in your code some BEGIN END you are missing

ELSE IF(@ID IS NOT NULL AND @ID in (SELECT ID FROM Places))   -- Outer Most Block ELSE IF
BEGIN   
     SELECT @MyName = Name ...  
    ...Some stuff....                       
    IF(SOMETHNG_1)         -- IF
                 --BEGIN
        BEGIN TRY               
            UPDATE ....                                                                 
        END TRY

        BEGIN CATCH
            SELECT ERROR_MESSAGE() AS 'Message' 
            RETURN -1
        END CATCH
                -- END
    ELSE IF(SOMETHNG_2)    -- ELSE IF
                 -- BEGIN
        BEGIN TRY
            UPDATE ...                                                      
        END TRY
        BEGIN CATCH
            SELECT ERROR_MESSAGE() AS 'Message' 
            RETURN -1
        END CATCH   
               -- END
    ELSE                  -- ELSE
        BEGIN
            BEGIN TRY
                UPDATE ...                                                              
            END TRY
            BEGIN CATCH
                SELECT ERROR_MESSAGE() AS 'Message' 
                RETURN -1
            END CATCH   
         END             
      --The above works I then insert this below and these if statement become nested----
          IF(@A!= @SA)
            BEGIN
             exec Store procedure 
                    @FIELD = 15,
                    ... more params...
            END                 
        IF(@S!= @SS)
          BEGIN
             exec Store procedure 
                    @FIELD = 10,
                    ... more params...

How do I get information about an index and table owner in Oracle?

The following helped me as I didn't have DBA access and also wanted the column names.

See: https://dataedo.com/kb/query/oracle/list-table-indexes

select ind.table_owner || '.' || ind.table_name as "TABLE",
       ind.index_name,
       LISTAGG(ind_col.column_name, ',')
            WITHIN GROUP(order by ind_col.column_position) as columns,
       ind.index_type,
       ind.uniqueness
from sys.all_indexes ind
join sys.all_ind_columns ind_col
           on ind.owner = ind_col.index_owner
           and ind.index_name = ind_col.index_name
where ind.table_owner not in ('ANONYMOUS','CTXSYS','DBSNMP','EXFSYS',
       'MDSYS', 'MGMT_VIEW','OLAPSYS','OWBSYS','ORDPLUGINS', 'ORDSYS',
       'SI_INFORMTN_SCHEMA','SYS','SYSMAN','SYSTEM', 'TSMSYS','WK_TEST',
       'WKPROXY','WMSYS','XDB','APEX_040000','APEX_040200',
       'DIP', 'FLOWS_30000','FLOWS_FILES','MDDATA', 'ORACLE_OCM', 'XS$NULL',
       'SPATIAL_CSW_ADMIN_USR', 'SPATIAL_WFS_ADMIN_USR', 'PUBLIC',
       'LBACSYS', 'OUTLN', 'WKSYS', 'APEX_PUBLIC_USER')
    -- AND ind.table_name='TableNameGoesHereIfYouWantASpecificTable'
group by ind.table_owner,
         ind.table_name,
         ind.index_name,
         ind.index_type,
         ind.uniqueness 
order by ind.table_owner,
         ind.table_name;

Iterate over array of objects in Typescript

You can use the built-in forEach function for arrays.

Like this:

//this sets all product descriptions to a max length of 10 characters
data.products.forEach( (element) => {
    element.product_desc = element.product_desc.substring(0,10);
});

Your version wasn't wrong though. It should look more like this:

for(let i=0; i<data.products.length; i++){
    console.log(data.products[i].product_desc); //use i instead of 0
}

Add padding on view programmatically

Write Following Code to set padding, it may help you.

TextView ApplyPaddingTextView = (TextView)findViewById(R.id.textView1);
final LayoutParams layoutparams = (RelativeLayout.LayoutParams) ApplyPaddingTextView.getLayoutParams();

layoutparams.setPadding(50,50,50,50);

ApplyPaddingTextView.setLayoutParams(layoutparams);

Use LinearLayout.LayoutParams or RelativeLayout.LayoutParams according to parent layout of the child view

android get all contacts

public class MyActivity extends Activity 
                        implements LoaderManager.LoaderCallbacks<Cursor> {

    private static final int CONTACTS_LOADER_ID = 1;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // Prepare the loader.  Either re-connect with an existing one,
        // or start a new one.
        getLoaderManager().initLoader(CONTACTS_LOADER_ID,
                                      null,
                                      this);
    }

    @Override
    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        // This is called when a new Loader needs to be created.

        if (id == CONTACTS_LOADER_ID) {
            return contactsLoader();
        }
        return null;
    }

    @Override
    public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
        //The framework will take care of closing the
        // old cursor once we return.
        List<String> contacts = contactsFromCursor(cursor);
    }

    @Override
    public void onLoaderReset(Loader<Cursor> loader) {
        // This is called when the last Cursor provided to onLoadFinished()
        // above is about to be closed.  We need to make sure we are no
        // longer using it.
    }

    private  Loader<Cursor> contactsLoader() {
        Uri contactsUri = ContactsContract.Contacts.CONTENT_URI; // The content URI of the phone contacts

        String[] projection = {                                  // The columns to return for each row
                ContactsContract.Contacts.DISPLAY_NAME
        } ;

        String selection = null;                                 //Selection criteria
        String[] selectionArgs = {};                             //Selection criteria
        String sortOrder = null;                                 //The sort order for the returned rows

        return new CursorLoader(
                getApplicationContext(),
                contactsUri,
                projection,
                selection,
                selectionArgs,
                sortOrder);
    }

    private List<String> contactsFromCursor(Cursor cursor) {
        List<String> contacts = new ArrayList<String>();

        if (cursor.getCount() > 0) {
            cursor.moveToFirst();

            do {
                String name = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
                contacts.add(name);
            } while (cursor.moveToNext());
        }

        return contacts;
    }

}

and do not forget

<uses-permission android:name="android.permission.READ_CONTACTS" />

How can I get the client's IP address in ASP.NET MVC?

In a class you might call it like this:

public static string GetIPAddress(HttpRequestBase request) 
{
    string ip;
    try
    {
        ip = request.ServerVariables["HTTP_X_FORWARDED_FOR"];
        if (!string.IsNullOrEmpty(ip))
        {
            if (ip.IndexOf(",") > 0)
            {
                string[] ipRange = ip.Split(',');
                int le = ipRange.Length - 1;
                ip = ipRange[le];
            }
        } else
        {
            ip = request.UserHostAddress;
        }
    } catch { ip = null; }

    return ip; 
}

I used this in a razor app with great results.

Oracle PL/SQL - Raise User-Defined Exception With Custom SQLERRM

create or replace PROCEDURE PROC_USER_EXP 
AS
duplicate_exp EXCEPTION;
PRAGMA EXCEPTION_INIT( duplicate_exp, -20001 );
LVCOUNT NUMBER;
BEGIN
  SELECT COUNT(*) INTO LVCOUNT FROM JOBS WHERE JOB_TITLE='President';
  IF LVCOUNT >1 THEN 
   raise_application_error( -20001, 'Duplicate president customer excetpion' );
  END IF;

  EXCEPTION 
  WHEN duplicate_exp THEN 
  DBMS_OUTPUT.PUT_LINE(sqlerrm);
END PROC_USER_EXP;

ORACLE 11g output will be like this:

Connecting to the database HR. 
ORA-20001: Duplicate president customer excetpion 
Process exited. 
Disconnecting from the database HR

How to add white spaces in HTML paragraph

You can try it by adding &nbsp;

How do I set response headers in Flask?

You can do this pretty easily:

@app.route("/")
def home():
    resp = flask.Response("Foo bar baz")
    resp.headers['Access-Control-Allow-Origin'] = '*'
    return resp

Look at flask.Response and flask.make_response()

But something tells me you have another problem, because the after_request should have handled it correctly too.

EDIT
I just noticed you are already using make_response which is one of the ways to do it. Like I said before, after_request should have worked as well. Try hitting the endpoint via curl and see what the headers are:

curl -i http://127.0.0.1:5000/your/endpoint

You should see

> curl -i 'http://127.0.0.1:5000/'
HTTP/1.0 200 OK
Content-Type: text/html; charset=utf-8
Content-Length: 11
Access-Control-Allow-Origin: *
Server: Werkzeug/0.8.3 Python/2.7.5
Date: Tue, 16 Sep 2014 03:47:13 GMT

Noting the Access-Control-Allow-Origin header.

EDIT 2
As I suspected, you are getting a 500 so you are not setting the header like you thought. Try adding app.debug = True before you start the app and try again. You should get some output showing you the root cause of the problem.

For example:

@app.route("/")
def home():
    resp = flask.Response("Foo bar baz")
    user.weapon = boomerang
    resp.headers['Access-Control-Allow-Origin'] = '*'
    return resp

Gives a nicely formatted html error page, with this at the bottom (helpful for curl command)

Traceback (most recent call last):
...
  File "/private/tmp/min.py", line 8, in home
    user.weapon = boomerang
NameError: global name 'boomerang' is not defined

Error: No default engine was specified and no extension was provided

If you wish to render a html file, use:

response.sendfile('index.html');

Then you remove:

app.set('view engine', 'html');

Put your *.html in the views directory, or serve a public directory as static dir and put the index.html in the public dir.

Set focus and cursor to end of text input field / string w. Jquery

You can do this using Input.setSelectionRange, part of the Range API for interacting with text selections and the text cursor:

var searchInput = $('#Search');

// Multiply by 2 to ensure the cursor always ends up at the end;
// Opera sometimes sees a carriage return as 2 characters.
var strLength = searchInput.val().length * 2;

searchInput.focus();
searchInput[0].setSelectionRange(strLength, strLength);

Demo: Fiddle

Strip HTML from Text JavaScript

function stripHTML(my_string){
    var charArr   = my_string.split(''),
        resultArr = [],
        htmlZone  = 0,
        quoteZone = 0;
    for( x=0; x < charArr.length; x++ ){
     switch( charArr[x] + htmlZone + quoteZone ){
       case "<00" : htmlZone  = 1;break;
       case ">10" : htmlZone  = 0;resultArr.push(' ');break;
       case '"10' : quoteZone = 1;break;
       case "'10" : quoteZone = 2;break;
       case '"11' : 
       case "'12" : quoteZone = 0;break;
       default    : if(!htmlZone){ resultArr.push(charArr[x]); }
     }
    }
    return resultArr.join('');
}

Accounts for > inside attributes and <img onerror="javascript"> in newly created dom elements.

usage:

clean_string = stripHTML("string with <html> in it")

demo:

https://jsfiddle.net/gaby_de_wilde/pqayphzd/

demo of top answer doing the terrible things:

https://jsfiddle.net/gaby_de_wilde/6f0jymL6/1/

Loading inline content using FancyBox

The way I figured this out was going through the example index.html/style.css that comes packaged with the Fancybox installation.

If you view the code that is used for the demo website and basically copy/paste, you'll be fine.

To get an inline Fancybox working, you will need to have this code present in your index.html file:

  <head>
    <link href="./fancybox/jquery.fancybox-1.3.4.css" rel="stylesheet" type="text/css" media="screen" />
    <script>!window.jQuery && document.write('<script src="jquery-1.4.3.min.js"><\/script>');</script>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"></script>
    <script type="text/javascript" src="./fancybox/jquery.fancybox-1.3.4.pack.js"></script>
    <script type="text/javascript">
    $(document).ready(function() {

    $("#various1").fancybox({
            'titlePosition'     : 'inside',
            'transitionIn'      : 'none',
            'transitionOut'     : 'none'
        });
    });
    </script>
  </head>

 <body>

    <a id="various1" href="#inline1" title="Put a title here">Name of Link Here</a>
    <div style="display: none;">
        <div id="inline1" style="width:400px;height:100px;overflow:auto;">
                   Write whatever text you want right here!!
        </div>
    </div> 

</body>

Remember to be precise about what folders your script files are placed in and where you are pointing to in the Head tag; they must correspond.

How to take the first N items from a generator or list?

@Shaikovsky's answer is excellent (…and heavily edited since I posted this answer), but I wanted to clarify a couple of points.

[next(generator) for _ in range(n)]

This is the most simple approach, but throws StopIteration if the generator is prematurely exhausted.


On the other hand, the following approaches return up to n items which is preferable in many circumstances:

List: [x for _, x in zip(range(n), records)]

Generator: (x for _, x in zip(range(n), records))

HTTP 401 - what's an appropriate WWW-Authenticate header value?

When indicating HTTP Basic Authentication we return something like:

WWW-Authenticate: Basic realm="myRealm"

Whereas Basic is the scheme and the remainder is very much dependent on that scheme. In this case realm just provides the browser a literal that can be displayed to the user when prompting for the user id and password.

You're obviously not using Basic however since there is no point having session expiry when Basic Auth is used. I assume you're using some form of Forms based authentication.

From recollection, Windows Challenge Response uses a different scheme and different arguments.

The trick is that it's up to the browser to determine what schemes it supports and how it responds to them.

My gut feel if you are using forms based authentication is to stay with the 200 + relogin page but add a custom header that the browser will ignore but your AJAX can identify.

For a really good User + AJAX experience, get the script to hang on to the AJAX request that found the session expired, fire off a relogin request via a popup, and on success, resubmit the original AJAX request and carry on as normal.

Avoid the cheat that just gets the script to hit the site every 5 mins to keep the session alive cause that just defeats the point of session expiry.

The other alternative is burn the AJAX request but that's a poor user experience.

flutter corner radius with transparent background

It's an old question. But for those who come across this question...

The white background behind the rounded corners is not actually the container. That is the canvas color of the app.

TO FIX: Change the canvas color of your app to Colors.transparent

Example:

return new MaterialApp(
  title: 'My App',
  theme: new ThemeData(
    primarySwatch: Colors.green,
    canvasColor: Colors.transparent, //----Change to this------------
    accentColor: Colors.blue,
  ),
  home: new HomeScreen(),
);

How can I disable a tab inside a TabControl?

The only way is to catch the Selecting event and prevent a tab from being activated.

Purge Kafka Topic

Another, rather manual, approach for purging a topic is:

in the brokers:

  1. stop kafka broker
    sudo service kafka stop
  2. delete all partition log files (should be done on all brokers)
    sudo rm -R /kafka-storage/kafka-logs/<some_topic_name>-*

in zookeeper:

  1. run zookeeper command line interface
    sudo /usr/lib/zookeeper/bin/zkCli.sh
  2. use zkCli to remove the topic metadata
    rmr /brokers/topic/<some_topic_name>

in the brokers again:

  1. restart broker service
    sudo service kafka start

How to iterate object in JavaScript?

Using a generator function you could iterate over deep key-values.

_x000D_
_x000D_
function * deepEntries(obj) { _x000D_
    for(let [key, value] of Object.entries(obj)) {_x000D_
        if (typeof value !== 'object') _x000D_
            yield [key, value]_x000D_
        else _x000D_
            for(let entries of deepEntries(value))_x000D_
                yield [key, ...entries]_x000D_
    }_x000D_
}_x000D_
_x000D_
const dictionary = {_x000D_
    "data": [_x000D_
        {"id":"0","name":"ABC"},_x000D_
        {"id":"1","name":"DEF"}_x000D_
    ],_x000D_
    "images": [_x000D_
        {"id":"0","name":"PQR"},_x000D_
        {"id":"1","name":"xyz"}_x000D_
    ]_x000D_
}_x000D_
_x000D_
for(let entries of deepEntries(dictionary)) {_x000D_
    const key = entries.slice(0, -1).join('.')_x000D_
    const value = entries[entries.length-1]_x000D_
    console.log(key, value)_x000D_
}
_x000D_
_x000D_
_x000D_

Background color in input and text fields

The best solution is the attribute selector in CSS (input[type="text"]) as the others suggested.

But if you have to support Internet Explorer 6, you cannot use it (QuirksMode). Well, only if you have to and also are willing to support it.

In this case your only option seems to be to define classes on input elements.

<input type="text" class="input-box" ... />
<input type="submit" class="button" ... />
...

and target them with a class selector:

input.input-box, textarea { background: cyan; }

using mailto to send email with an attachment

Nope, this is not possible at all. There is no provision for it in the mailto: protocol, and it would be a gaping security hole if it were possible.

The best idea to send a file, but have the client send the E-Mail that I can think of is:

  • Have the user choose a file
  • Upload the file to a server
  • Have the server return a random file name after upload
  • Build a mailto: link that contains the URL to the uploaded file in the message body

What is the keyguard in Android?

Yes, I also found it here: http://developer.android.com/tools/testing/activity_testing.html It's seems a key-input protection mechanism which includes the screen-lock, but not only includes it. According to this webpage, it also defines some key-input restriction for auto-test framework in Android.

Make an existing Git branch track a remote branch?

or simply by :

switch to the branch if you are not in it already:

[za]$ git checkout branch_name

run

[za]$ git branch --set-upstream origin branch_name
Branch origin set up to track local branch brnach_name by rebasing.

and you ready to :

 [za]$ git push origin branch_name

You can alawys take a look at the config file to see what is tracking what by running:

 [za]$ git config -e

It's also nice to know this, it shows which branches are tracked and which ones are not. :

  [za]$ git remote show origin 

Repeat string to certain length

Another FP aproach:

def repeat_string(string_to_repeat, repetitions):
    return ''.join([ string_to_repeat for n in range(repetitions)])

How to make rectangular image appear circular with CSS

I've been researching this very same problem and couldn't find a decent solution other than having the div with the image as background and the img tag inside of it with visibility none or something like this.

One thing I might add is that you should add a background-size: cover to the div, so that your image fills the background by clipping it's excess.

Cross-Origin Request Headers(CORS) with PHP headers

Many description internet-wide don't mention that specifying Access-Control-Allow-Origin is not enough. Here is a complete example that works for me:

<?php
    if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
        header('Access-Control-Allow-Origin: *');
        header('Access-Control-Allow-Methods: POST, GET, DELETE, PUT, PATCH, OPTIONS');
        header('Access-Control-Allow-Headers: token, Content-Type');
        header('Access-Control-Max-Age: 1728000');
        header('Content-Length: 0');
        header('Content-Type: text/plain');
        die();
    }

    header('Access-Control-Allow-Origin: *');
    header('Content-Type: application/json');

    $ret = [
        'result' => 'OK',
    ];
    print json_encode($ret);

Change border color on <select> HTML form

No, the <select> control is a system-level control, not a client-level control in IE. A few versions back it didn't even play nicely-with z-index, putting itself on top of virtually everything.

To do anything fancy you'll have to emulate the functionality using CSS and your own elements.

jQuery .each() index?

jQuery takes care of this for you. The first argument to your .each() callback function is the index of the current iteration of the loop. The second being the current matched DOM element So:

$('#list option').each(function(index, element){
  alert("Iteration: " + index)
});

@Autowired and static method

Use AppContext. Make sure you create a bean in your context file.

private final static Foo foo = AppContext.getApplicationContext().getBean(Foo.class);

public static void randomMethod() {
     foo.doStuff();
}

How to drop columns by name in a data frame

I tried to delete a column while using the package data.table and got an unexpected result. I kind of think the following might be worth posting. Just a little cautionary note.

[ Edited by Matthew ... ]

DF = read.table(text = "
     fruit state grade y1980 y1990 y2000
     apples Ohio   aa    500   100   55
     apples Ohio   bb      0     0   44
     apples Ohio   cc    700     0   33
     apples Ohio   dd    300    50   66
", sep = "", header = TRUE, stringsAsFactors = FALSE)

DF[ , !names(DF) %in% c("grade")]   # all columns other than 'grade'
   fruit state y1980 y1990 y2000
1 apples  Ohio   500   100    55
2 apples  Ohio     0     0    44
3 apples  Ohio   700     0    33
4 apples  Ohio   300    50    66

library('data.table')
DT = as.data.table(DF)

DT[ , !names(dat4) %in% c("grade")]    # not expected !! not the same as DF !!
[1]  TRUE  TRUE FALSE  TRUE  TRUE  TRUE

DT[ , !names(DT) %in% c("grade"), with=FALSE]    # that's better
    fruit state y1980 y1990 y2000
1: apples  Ohio   500   100    55
2: apples  Ohio     0     0    44
3: apples  Ohio   700     0    33
4: apples  Ohio   300    50    66

Basically, the syntax for data.table is NOT exactly the same as data.frame. There are in fact lots of differences, see FAQ 1.1 and FAQ 2.17. You have been warned!

Generate a UUID on iOS from Swift

Each time the same will be generated:

if let uuid = UIDevice.current.identifierForVendor?.uuidString {
    print(uuid)
}

Each time a new one will be generated:

let uuid = UUID().uuidString
print(uuid)

How to exclude particular class name in CSS selector?

One way is to use the multiple class selector (no space as that is the descendant selector):

_x000D_
_x000D_
.reMode_hover:not(.reMode_selected):hover _x000D_
{_x000D_
   background-color: #f0ac00;_x000D_
}
_x000D_
<a href="" title="Design" class="reMode_design  reMode_hover">_x000D_
    <span>Design</span>_x000D_
</a>_x000D_
_x000D_
<a href="" title="Design" _x000D_
 class="reMode_design  reMode_hover reMode_selected">_x000D_
    <span>Design</span>_x000D_
</a>
_x000D_
_x000D_
_x000D_

Capture close event on Bootstrap Modal

I was having this same problem in a web app using Microsoft Visual Studio 2019, Asp.Net 3.1 and Bootstrap 4.5. I had a modal form open to add a new staff person (only a few input fields) and the Add Staff button would invoke an ajax call to create the staff records in the database. Upon successful return the code would refresh the partial razor page of staff (so the new staff person would appear in the list).

Just before the refresh I would close the Add Staff modal and display a Please Wait modal which only had a bootstrap spinner button on it. What happened is that the Please Wait modal would stay displayed and not close after the staff refresh and the modal('hide') function on this modal was called. Some times the modal would disappear but the modal backdrop would remain effectively locking the Staff List form.

Since Bootstrap has issues with multiple modals open at once, I thought maybe the Add Staff modal was still open when the Please Wait modal was displayed and this was causing problems. I made a function to display the Please Wait modal and do the refresh, and called it using the Javascript function setTimeout() to wait 1/2 second after closing/hiding the Add Staff modal:

//hide the modal form
$("#addNewStaffModal").modal('hide');
setTimeout(RefreshStaffListAfterAddingStaff, 500); //wait for 1/2 second

Here is the code for the refresh function:

function RefreshStaffListAfterAddingStaff() {
    // refresh the staff list in our partial view

    //show the please wait message
    $('#PleaseWaitModal').modal('show');

    //refresh the partial view
    $('#StaffAccountsPartialView').load('StaffAccounts?handler=StaffAccountsPartial',
        function (data, status, jqXGR) {

            //hide the wait modal
            $('#PleaseWaitModal').modal('hide');
            // enable all the fields on our form
            $("#StaffAccountsForm :input").prop("disabled", false);

            //scroll to the top of the staff list window
            window.scroll({
                top: 0,
                left: 0,
                behavior: 'smooth'
            });

        });
}

This seems to have totally solved my problem!

Unable to run Java code with Intellij IDEA

-First Move Your Code Files in side the "src" Folder

-Make sure your Main method is declared like the following

   public class Main {
         public static void main(String []args){


       }
    }

then:

  • Go to Project configurations
  • select Java application,
  • check allow parallel run
  • and select your main class

and it should work

Add Keypair to existing EC2 instance

I didn't find an easy way to add a new key pair via the console, but you can do it manually.

Just ssh into your EC2 box with the existing key pair. Then edit the ~/.ssh/authorized_keys and add the new key on a new line. Exit and ssh via the new machine. Success!

Java SimpleDateFormat for time zone with a colon separator?

If date string is like 2018-07-20T12:18:29.802Z Use this

SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");

Select All as default value for Multivalue parameter

It works better

CREATE TABLE [dbo].[T_Status](
   [Status] [nvarchar](20) NULL
) ON [PRIMARY]

GO
INSERT [dbo].[T_Status] ([Status]) VALUES (N'Active')
GO
INSERT [dbo].[T_Status] ([Status]) VALUES (N'notActive')
GO
INSERT [dbo].[T_Status] ([Status]) VALUES (N'Active')
GO

DECLARE @GetStatus nvarchar(20) = null
--DECLARE @GetStatus nvarchar(20) = 'Active'
SELECT [Status]
FROM [T_Status]
WHERE  [Status] = CASE WHEN (isnull(@GetStatus, '')='') THEN [Status]
ELSE @GetStatus END

In C/C++ what's the simplest way to reverse the order of bits in a byte?

This one is based on the one BobStein-VisiBone provided

#define reverse_1byte(b)    ( ((uint8_t)b & 0b00000001) ? 0b10000000 : 0 ) | \
                            ( ((uint8_t)b & 0b00000010) ? 0b01000000 : 0 ) | \
                            ( ((uint8_t)b & 0b00000100) ? 0b00100000 : 0 ) | \
                            ( ((uint8_t)b & 0b00001000) ? 0b00010000 : 0 ) | \
                            ( ((uint8_t)b & 0b00010000) ? 0b00001000 : 0 ) | \
                            ( ((uint8_t)b & 0b00100000) ? 0b00000100 : 0 ) | \
                            ( ((uint8_t)b & 0b01000000) ? 0b00000010 : 0 ) | \
                            ( ((uint8_t)b & 0b10000000) ? 0b00000001 : 0 ) 

I really like this one a lot because the compiler automatically handle the work for you, thus require no further resources.

this can also be extended to 16-Bits...

#define reverse_2byte(b)    ( ((uint16_t)b & 0b0000000000000001) ? 0b1000000000000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000000000010) ? 0b0100000000000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000000000100) ? 0b0010000000000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000000001000) ? 0b0001000000000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000000010000) ? 0b0000100000000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000000100000) ? 0b0000010000000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000001000000) ? 0b0000001000000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000010000000) ? 0b0000000100000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000000100000000) ? 0b0000000010000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000001000000000) ? 0b0000000001000000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000010000000000) ? 0b0000000000100000 : 0 ) | \
                            ( ((uint16_t)b & 0b0000100000000000) ? 0b0000000000010000 : 0 ) | \
                            ( ((uint16_t)b & 0b0001000000000000) ? 0b0000000000001000 : 0 ) | \
                            ( ((uint16_t)b & 0b0010000000000000) ? 0b0000000000000100 : 0 ) | \
                            ( ((uint16_t)b & 0b0100000000000000) ? 0b0000000000000010 : 0 ) | \
                            ( ((uint16_t)b & 0b1000000000000000) ? 0b0000000000000001 : 0 ) 

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>

python xlrd unsupported format, or corrupt file.

Try to open it with pandas:

import pandas as pd
data = pd.read_html('filename.xls')

Or try any other html python parser.

That's not a proper excel file, but an html readable with excel.

How to run stored procedures in Entity Framework Core?

Support for stored procedures in EF Core 1.0 is resolved now, this also supports the mapping of multiple result-sets.

Check here for the fix details

And you can call it like this in c#

var userType = dbContext.Set().FromSql("dbo.SomeSproc @Id = {0}, @Name = {1}", 45, "Ada");

'any' vs 'Object'

Object appears to be a more specific declaration than any. From the TypeScript spec (section 3):

All types in TypeScript are subtypes of a single top type called the Any type. The any keyword references this type. The Any type is the one type that can represent any JavaScript value with no constraints. All other types are categorized as primitive types, object types, or type parameters. These types introduce various static constraints on their values.

Also:

The Any type is used to represent any JavaScript value. A value of the Any type supports the same operations as a value in JavaScript and minimal static type checking is performed for operations on Any values. Specifically, properties of any name can be accessed through an Any value and Any values can be called as functions or constructors with any argument list.

Objects do not allow the same flexibility.

For example:

var myAny : any;

myAny.Something(); // no problemo

var myObject : Object;

myObject.Something(); // Error: The property 'Something' does not exist on value of type 'Object'.

Proper usage of Java -D command-line parameters

That should be:

java -Dtest="true" -jar myApplication.jar

Then the following will return the value:

System.getProperty("test");

The value could be null, though, so guard against an exception using a Boolean:

boolean b = Boolean.parseBoolean( System.getProperty( "test" ) );

Note that the getBoolean method delegates the system property value, simplifying the code to:

if( Boolean.getBoolean( "test" ) ) {
   // ...
}

How to convert DateTime to VarChar

Write a function

CREATE FUNCTION dbo.TO_SAP_DATETIME(@input datetime)
RETURNS VARCHAR(14)
AS BEGIN
    DECLARE @ret VARCHAR(14)
    SET @ret = COALESCE(SUBSTRING(REPLACE(REPLACE(REPLACE(CONVERT(VARCHAR(26), @input, 25),'-',''),' ',''),':',''),1,14),'00000000000000');
    RETURN @ret
END

Pointer arithmetic for void pointer in C

The C standard does not allow void pointer arithmetic. However, GNU C is allowed by considering the size of void is 1.

C11 standard §6.2.5

Paragraph - 19

The void type comprises an empty set of values; it is an incomplete object type that cannot be completed.

Following program is working fine in GCC compiler.

#include<stdio.h>

int main()
{
    int arr[2] = {1, 2};
    void *ptr = &arr;
    ptr = ptr + sizeof(int);
    printf("%d\n", *(int *)ptr);
    return 0;
}

May be other compilers generate an error.

How to display a content in two-column layout in LaTeX?

You can import a csv file to this website(https://www.tablesgenerator.com/latex_tables) and click copy to clipboard.

How to set cookies in laravel 5 independently inside controller

You may try this:

Cookie::queue($name, $value, $minutes);

This will queue the cookie to use it later and later it will be added with the response when response is ready to be sent. You may check the documentation on Laravel website.

Update (Retrieving A Cookie Value):

$value = Cookie::get('name');

Note: If you set a cookie in the current request then you'll be able to retrieve it on the next subsequent request.

What's the difference between Thread start() and Runnable run()

invoke run() is executing on the calling thread, like any other method call. whereas Thread.start() creates a new thread. invoking run() is a programmatic bug.

VBA Public Array : how to?

This worked for me, seems to work as global :

Dim savePos(2 To 8) As Integer

And can call it from every sub, for example getting first element :

MsgBox (savePos(2))

What is the most "pythonic" way to iterate over a list in chunks?

This answer splits a list of strings, f.ex. to achieve PEP8-line length compliance:

def split(what, target_length=79):
    '''splits list of strings into sublists, each 
    having string length at most 79'''
    out = [[]]
    while what:
        if len("', '".join(out[-1])) + len(what[0]) < target_length:
            out[-1].append(what.pop(0))
        else:
            if not out[-1]: # string longer than target_length
                out[-1] = [what.pop(0)]
            out.append([])
    return out

Use as

>>> split(['deferred_income', 'long_term_incentive', 'restricted_stock_deferred', 'shared_receipt_with_poi', 'loan_advances', 'from_messages', 'other', 'director_fees', 'bonus', 'total_stock_value', 'from_poi_to_this_person', 'from_this_person_to_poi', 'restricted_stock', 'salary', 'total_payments', 'exercised_stock_options'], 75)
[['deferred_income', 'long_term_incentive', 'restricted_stock_deferred'], ['shared_receipt_with_poi', 'loan_advances', 'from_messages', 'other'], ['director_fees', 'bonus', 'total_stock_value', 'from_poi_to_this_person'], ['from_this_person_to_poi', 'restricted_stock', 'salary', 'total_payments'], ['exercised_stock_options']]

Hexadecimal To Decimal in Shell Script

Dealing with a very lightweight embedded version of busybox on Linux means many of the traditional commands are not available (bc, printf, dc, perl, python)

echo $((0x2f))
47

hexNum=2f
echo $((0x${hexNum}))
47

Credit to Peter Leung for this solution.

Replace text inside td using jQuery having td containing other elements

Remove the textnode, and replace the <b> tag with whatever you need without ever touching the inputs :

$('#demoTable').find('tr > td').contents().filter(function() {
    return this.nodeType===3;
}).remove().end().end()
  .find('b').replaceWith($('<span />', {text: 'Hello Kitty'}));

FIDDLE

How do I set a fixed background image for a PHP file?

You should consider have other php files included if you're going to derive a website from it. Instead of doing all the css/etc in that file, you can do

<head>
    <?php include_once('C:\Users\George\Documents\HTML\style.css'); ?>
    <title>Title</title>
</hea>

Then you can have a separate CSS file that is just being pulled into your php file. It provides some "neater" coding.

Angular 2 Sibling Component Communication

Here is simple practical explanation:Simply explained here

In call.service.ts

import { Observable } from 'rxjs';
import { Subject } from 'rxjs/Subject';

@Injectable()
export class CallService {
 private subject = new Subject<any>();

 sendClickCall(message: string) {
    this.subject.next({ text: message });
 }

 getClickCall(): Observable<any> {
    return this.subject.asObservable();
 }
}

Component from where you want to call observable to inform another component that button is clicked

import { CallService } from "../../../services/call.service";

export class MarketplaceComponent implements OnInit, OnDestroy {
  constructor(public Util: CallService) {

  }

  buttonClickedToCallObservable() {
   this.Util.sendClickCall('Sending message to another comp that button is clicked');
  }
}

Component where you want to perform action on button clicked on another component

import { Subscription } from 'rxjs/Subscription';
import { CallService } from "../../../services/call.service";


ngOnInit() {

 this.subscription = this.Util.getClickCall().subscribe(message => {

 this.message = message;

 console.log('---button clicked at another component---');

 //call you action which need to execute in this component on button clicked

 });

}

import { Subscription } from 'rxjs/Subscription';
import { CallService } from "../../../services/call.service";


ngOnInit() {

 this.subscription = this.Util.getClickCall().subscribe(message => {

 this.message = message;

 console.log('---button clicked at another component---');

 //call you action which need to execute in this component on button clicked

});

}

My understanding clear on components communication by reading this: http://musttoknow.com/angular-4-angular-5-communicate-two-components-using-observable-subject/

Cancel a vanilla ECMAScript 6 Promise chain

While there isn't a standard way of doing this in ES6, there is a library called Bluebird to handle this.

There is also a recommended way described as part of the react documentation. It looks similar to what you have in your 2 and 3rd updates.

const makeCancelable = (promise) => {
  let hasCanceled_ = false;

  const wrappedPromise = new Promise((resolve, reject) => {
    promise.then((val) =>
      hasCanceled_ ? reject({isCanceled: true}) : resolve(val)
    );
    promise.catch((error) =>
      hasCanceled_ ? reject({isCanceled: true}) : reject(error)
    );
  });

  return {
    promise: wrappedPromise,
    cancel() {
      hasCanceled_ = true;
    },
  };
};

const cancelablePromise = makeCancelable(
  new Promise(r => component.setState({...}}))
);

cancelablePromise
  .promise
  .then(() => console.log('resolved'))
  .catch((reason) => console.log('isCanceled', reason.isCanceled));

cancelablePromise.cancel(); // Cancel the promise

Taken from: https://facebook.github.io/react/blog/2015/12/16/ismounted-antipattern.html

How do I create a new line in Javascript?

Alternatively, write to an element with the CSS white-space: pre and use \n for newline character.

Typescript: How to define type for a function callback (as any function type, not universal any) used in a method parameter

Hopefully, this will help...

interface Param {
    title: string;
    callback: (error: Error, data: string) => void;
}

Or in a Function


let myfunction = (title: string, callback: (error: Error, data: string) => void): string => {

    callback(new Error(`Error Message Here.`), "This is callback data.");
    return title;

}

How To limit the number of characters in JTextField?

Just put this code in KeyTyped event:

    if ((jtextField.getText() + evt.getKeyChar()).length() > 20) {
        evt.consume();
    }

Where "20" is the maximum number of characters that you want.

Navigation drawer: How do I set the selected item at startup?

Easiest way is to select it from xml as follows,

<menu>
   <group android:checkableBehavior="single">
         <item
              android:checked="true"
              android:id="@+id/nav_home"
              android:icon="@drawable/nav_home"
              android:title="@string/main_screen_title_home" />

Note the line android:checked="true"

User Authentication in ASP.NET Web API

I am working on a MVC5/Web API project and needed to be able to get authorization for the Web Api methods. When my index view is first loaded I make a call to the 'token' Web API method which I believe is created automatically.

The client side code (CoffeeScript) to get the token is:

getAuthenticationToken = (username, password) ->
    dataToSend = "username=" + username + "&password=" + password
    dataToSend += "&grant_type=password"
    $.post("/token", dataToSend).success saveAccessToken

If successful the following is called, which saves the authentication token locally:

saveAccessToken = (response) ->
    window.authenticationToken = response.access_token

Then if I need to make an Ajax call to a Web API method that has the [Authorize] tag I simply add the following header to my Ajax call:

{ "Authorization": "Bearer " + window.authenticationToken }

onClick not working on mobile (touch)

better to use touchstart event with .on() jQuery method:

$(window).load(function() { // better to use $(document).ready(function(){
    $('.List li').on('click touchstart', function() {
        $('.Div').slideDown('500');
    });
});

And i don't understand why you are using $(window).load() method because it waits for everything on a page to be loaded, this tend to be slow, while you can use $(document).ready() method which does not wait for each element on the page to be loaded first.

scale fit mobile web content using viewport meta tag

For Android there is the addition of target-density tag.

target-densitydpi=device-dpi

So, the code would look like

<meta name="viewport" content="width=device-width, target-densitydpi=device-dpi, initial-scale=0, maximum-scale=1, user-scalable=yes" />

Please note, that I believe this addition is only for Android (but since you have answers, I felt this was a good extra) but this should work for most mobile devices.

In JPA 2, using a CriteriaQuery, how to count results

As others answers are correct, but too simple, so for completeness I'm presenting below code snippet to perform SELECT COUNT on a sophisticated JPA Criteria query (with multiple joins, fetches, conditions).

It is slightly modified this answer.

public <T> long count(final CriteriaBuilder cb, final CriteriaQuery<T> selectQuery,
        Root<T> root) {
    CriteriaQuery<Long> query = createCountQuery(cb, selectQuery, root);
    return this.entityManager.createQuery(query).getSingleResult();
}

private <T> CriteriaQuery<Long> createCountQuery(final CriteriaBuilder cb,
        final CriteriaQuery<T> criteria, final Root<T> root) {

    final CriteriaQuery<Long> countQuery = cb.createQuery(Long.class);
    final Root<T> countRoot = countQuery.from(criteria.getResultType());

    doJoins(root.getJoins(), countRoot);
    doJoinsOnFetches(root.getFetches(), countRoot);

    countQuery.select(cb.count(countRoot));
    countQuery.where(criteria.getRestriction());

    countRoot.alias(root.getAlias());

    return countQuery.distinct(criteria.isDistinct());
}

@SuppressWarnings("unchecked")
private void doJoinsOnFetches(Set<? extends Fetch<?, ?>> joins, Root<?> root) {
    doJoins((Set<? extends Join<?, ?>>) joins, root);
}

private void doJoins(Set<? extends Join<?, ?>> joins, Root<?> root) {
    for (Join<?, ?> join : joins) {
        Join<?, ?> joined = root.join(join.getAttribute().getName(), join.getJoinType());
        joined.alias(join.getAlias());
        doJoins(join.getJoins(), joined);
    }
}

private void doJoins(Set<? extends Join<?, ?>> joins, Join<?, ?> root) {
    for (Join<?, ?> join : joins) {
        Join<?, ?> joined = root.join(join.getAttribute().getName(), join.getJoinType());
        joined.alias(join.getAlias());
        doJoins(join.getJoins(), joined);
    }
}

Hope it saves somebody's time.

Because IMHO JPA Criteria API is not intuitive nor quite readable.

Getting realtime output using subprocess

In Python 3.x the process might hang because the output is a byte array instead of a string. Make sure you decode it into a string.

Starting from Python 3.6 you can do it using the parameter encoding in Popen Constructor. The complete example:

process = subprocess.Popen(
    'my_command',
    stdout=subprocess.PIPE,
    stderr=subprocess.STDOUT,
    shell=True,
    encoding='utf-8',
    errors='replace'
)

while True:
    realtime_output = process.stdout.readline()

    if realtime_output == '' and process.poll() is not None:
        break

    if realtime_output:
        print(realtime_output.strip(), flush=True)

Note that this code redirects stderr to stdout and handles output errors.

gradlew command not found?

Linux / MacOS

As noted in the comments, just running

./gradlew

worked for me. Adding the ./ tells it to look in the current directory since it isn't in the path.

Windows PowerShell

.\gradlew

Unable to read repository at http://download.eclipse.org/releases/indigo

Please make sure you are using correct url. If You are using url - http://download.eclipse.org/releases/indigo on your eclipse luna(v4.4) then it might be not working in this case you should use - http://download.eclipse.org/releases/luna

I have tried this and its working.

Automatically open Chrome developer tools when new tab/new window is opened

On opening the developer tools, with the developer tools window in focus, press F1. This will open a settings page. Check the "Auto-open DevTools for popups".

This worked for me.

Screenshot

How can I check file size in Python?

import os


def convert_bytes(num):
    """
    this function will convert bytes to MB.... GB... etc
    """
    for x in ['bytes', 'KB', 'MB', 'GB', 'TB']:
        if num < 1024.0:
            return "%3.1f %s" % (num, x)
        num /= 1024.0


def file_size(file_path):
    """
    this function will return the file size
    """
    if os.path.isfile(file_path):
        file_info = os.stat(file_path)
        return convert_bytes(file_info.st_size)


# Lets check the file size of MS Paint exe 
# or you can use any file path
file_path = r"C:\Windows\System32\mspaint.exe"
print file_size(file_path)

Result:

6.1 MB

Dismissing a Presented View Controller

Swift

let rootViewController:UIViewController = (UIApplication.shared.keyWindow?.rootViewController)!

        if (rootViewController.presentedViewController != nil) {
            rootViewController.dismiss(animated: true, completion: {
                //completion block.
            })
        }

php execute a background process

For those of us using Windows, look at this:

Reference: http://php.net/manual/en/function.exec.php#43917

I too wrestled with getting a program to run in the background in Windows while the script continues to execute. This method unlike the other solutions allows you to start any program minimized, maximized, or with no window at all. llbra@phpbrasil's solution does work but it sometimes produces an unwanted window on the desktop when you really want the task to run hidden.

start Notepad.exe minimized in the background:

<?php 
$WshShell = new COM("WScript.Shell"); 
$oExec = $WshShell->Run("notepad.exe", 7, false); 
?> 

start a shell command invisible in the background:

<?php 
$WshShell = new COM("WScript.Shell"); 
$oExec = $WshShell->Run("cmd /C dir /S %windir%", 0, false); 
?> 

start MSPaint maximized and wait for you to close it before continuing the script:

<?php 
$WshShell = new COM("WScript.Shell"); 
$oExec = $WshShell->Run("mspaint.exe", 3, true); 
?> 

For more info on the Run() method go to: http://msdn.microsoft.com/library/en-us/script56/html/wsMthRun.asp

Edited URL:

Go to https://technet.microsoft.com/en-us/library/ee156605.aspx instead as the link above no longer exists.

Converting a generic list to a CSV string

For whatever reason, @AliUmair reverted the edit to his answer that fixes his code that doesn't run as is, so here is the working version that doesn't have the file access error and properly handles null object property values:

/// <summary>
/// Creates the CSV from a generic list.
/// </summary>;
/// <typeparam name="T"></typeparam>;
/// <param name="list">The list.</param>;
/// <param name="csvNameWithExt">Name of CSV (w/ path) w/ file ext.</param>;
public static void CreateCSVFromGenericList<T>(List<T> list, string csvCompletePath)
{
    if (list == null || list.Count == 0) return;

    //get type from 0th member
    Type t = list[0].GetType();
    string newLine = Environment.NewLine;

    if (!Directory.Exists(Path.GetDirectoryName(csvCompletePath))) Directory.CreateDirectory(Path.GetDirectoryName(csvCompletePath));

    using (var sw = new StreamWriter(csvCompletePath))
    {
        //make a new instance of the class name we figured out to get its props
        object o = Activator.CreateInstance(t);
        //gets all properties
        PropertyInfo[] props = o.GetType().GetProperties();

        //foreach of the properties in class above, write out properties
        //this is the header row
        sw.Write(string.Join(",", props.Select(d => d.Name).ToArray()) + newLine);

        //this acts as datarow
        foreach (T item in list)
        {
            //this acts as datacolumn
            var row = string.Join(",", props.Select(d => $"\"{item.GetType().GetProperty(d.Name).GetValue(item, null)?.ToString()}\"")
                                                    .ToArray());
            sw.Write(row + newLine);

        }
    }
}

javascript jquery radio button click

There are several ways to do this. Having a container around the radio buttons is highly recommended regardless, but you can also put a class directly on the buttons. With this HTML:

<ul id="shapeList" class="radioList">
<li><label>Shape:</label></li>
<li><input id="shapeList_0" class="shapeButton" type="radio" value="Circular" name="shapeList" /><label for="shapeList_0">Circular</label></li>
<li><input id="shapeList_1" class="shapeButton" type="radio" value="Rectangular" name="shapeList" /><label for="shapeList_1">Rectangular</label></li>
</ul>

you can select by class:

$(".shapeButton").click(SetShape);

or select by container ID:

$("#shapeList").click(SetShape);

In either case, the event will trigger on clicking either the radio button or the label for it, though oddly in the latter case (Selecting by "#shapeList"), clicking on the label will trigger the click function twice for some reason, at least in FireFox; selecting by class won't do that.

SetShape is a function, and looks like this:

function SetShape() {
    var Shape = $('.shapeButton:checked').val();
//dostuff
}

This way, you can have labels on your buttons, and can have multiple radio button lists on the same page that do different things. You can even have each individual button in the same list do different things by setting up different behavior in SetShape() based on the button's value.

How to get DropDownList SelectedValue in Controller in MVC

Model

Very basic model with Gender field. GetGenderSelectItems() returns select items needed to populate DropDownList.

public enum Gender 
{
    Male, Female
}

public class MyModel
{
    public Gender Gender { get; set; }

    public static IEnumerable<SelectListItem> GetGenderSelectItems()
    {
        yield return new SelectListItem { Text = "Male", Value = "Male" };
        yield return new SelectListItem { Text = "Female", Value = "Female" };
    }
}

View

Please make sure you wrapped your @Html.DropDownListFor in a form tag.

@model MyModel

@using (Html.BeginForm("MyController", "MyAction", FormMethod.Post)
{
   @Html.DropDownListFor(m => m.Gender, MyModel.GetGenderSelectItems())
   <input type="submit" value="Send" />
}

Controller

Your .cshtml Razor view name should be the same as controller action name and folder name should match controller name e.g Views\MyController\MyAction.cshtml.

public class MyController : Controller 
{
    public ActionResult MyAction()
    {
        // shows your form when you load the page
        return View();
    }

    [HttpPost]
    public ActionResult MyAction(MyModel model)
    {
        // the value is received in the controller.
        var selectedGender = model.Gender;
        return View(model);
    }
}

Going further

Now let's make it strongly-typed and enum independent:

var genderSelectItems = Enum.GetValues(typeof(Gender))
    .Cast<string>()
    .Select(genderString => new SelectListItem 
    {
        Text = genderString,
        Value = genderString,
    }).AsEnumerable();

R ggplot2: stat_count() must not be used with a y aesthetic error in Bar graph

You can use geom_col() directly. See the differences between geom_bar() and geom_col() in this link https://ggplot2.tidyverse.org/reference/geom_bar.html

geom_bar() makes the height of the bar proportional to the number of cases in each group If you want the heights of the bars to represent values in the data, use geom_col() instead.

ggplot(data_country)+aes(x=country,y = conversion_rate)+geom_col()

How to insert an item into an array at a specific index (JavaScript)?

I tried this and it is working fine!

var initialArr = ["India","China","Japan","USA"];
initialArr.splice(index, 0, item);

Index is the position where you want to insert or delete the element. 0 i.e. the second parameters defines the number of element from the index to be removed item are the new entries which you want to make in array. It can be one or more than one.

initialArr.splice(2, 0, "Nigeria");
initialArr.splice(2, 0, "Australia","UK");

JavaScript associative array to JSON

You might want to push the object into the array

enter code here

var AssocArray = new Array();

AssocArray.push( "The letter A");

console.log("a = " + AssocArray[0]);

// result: "a = The letter A"

console.log( AssocArray[0]);

JSON.stringify(AssocArray);

Getting the text from a drop-down box

function getValue(obj)
{  
   // it will return the selected text
   // obj variable will contain the object of check box
   var text = obj.options[obj.selectedIndex].innerHTML ; 

}

HTML Snippet

 <asp:DropDownList ID="ddl" runat="server" CssClass="ComboXXX" 
  onchange="getValue(this)">
</asp:DropDownList>

Objective-C and Swift URL encoding

To escape the characters you want is a little more work.

Example code

iOS7 and above:

NSString *unescaped = @"http://www";
NSString *escapedString = [unescaped stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLHostAllowedCharacterSet]];
NSLog(@"escapedString: %@", escapedString);

NSLog output:

escapedString: http%3A%2F%2Fwww

The following are useful URL encoding character sets:

URLFragmentAllowedCharacterSet  "#%<>[\]^`{|}
URLHostAllowedCharacterSet      "#%/<>?@\^`{|}
URLPasswordAllowedCharacterSet  "#%/:<>?@[\]^`{|}
URLPathAllowedCharacterSet      "#%;<>?[\]^`{|}
URLQueryAllowedCharacterSet     "#%<>[\]^`{|}
URLUserAllowedCharacterSet      "#%/:<>?@[\]^`

Creating a characterset combining all of the above:

NSCharacterSet *URLCombinedCharacterSet = [[NSCharacterSet characterSetWithCharactersInString:@" \"#%/:<>?@[\\]^`{|}"] invertedSet];

Creating a Base64

In the case of Base64 characterset:

NSCharacterSet *URLBase64CharacterSet = [[NSCharacterSet characterSetWithCharactersInString:@"/+=\n"] invertedSet];

For Swift 3.0:

var escapedString = originalString.addingPercentEncoding(withAllowedCharacters:.urlHostAllowed)

For Swift 2.x:

var escapedString = originalString.stringByAddingPercentEncodingWithAllowedCharacters(NSCharacterSet.URLHostAllowedCharacterSet())

Note: stringByAddingPercentEncodingWithAllowedCharacters will also encode UTF-8 characters needing encoding.

Pre iOS7 use Core Foundation
Using Core Foundation With ARC:

NSString *escapedString = (NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(
    NULL,
   (__bridge CFStringRef) unescaped,
    NULL,
    CFSTR("!*'();:@&=+$,/?%#[]\" "),
    kCFStringEncodingUTF8));

Using Core Foundation Without ARC:

NSString *escapedString = (NSString *)CFURLCreateStringByAddingPercentEscapes(
    NULL,
   (CFStringRef)unescaped,
    NULL,
    CFSTR("!*'();:@&=+$,/?%#[]\" "),
    kCFStringEncodingUTF8);

Note: -stringByAddingPercentEscapesUsingEncoding will not produce the correct encoding, in this case it will not encode anything returning the same string.

stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding encodes 14 characrters:

`#%^{}[]|\"<> plus the space character as percent escaped.

testString:

" `~!@#$%^&*()_+-={}[]|\\:;\"'<,>.?/AZaz"  

encodedString:

"%20%60~!@%23$%25%5E&*()_+-=%7B%7D%5B%5D%7C%5C:;%22'%3C,%3E.?/AZaz"  

Note: consider if this set of characters meet your needs, if not change them as needed.

RFC 3986 characters requiring encoding (% added since it is the encoding prefix character):

"!#$&'()*+,/:;=?@[]%"

Some "unreserved characters" are additionally encoded:

"\n\r \"%-.<>\^_`{|}~"

What does "static" mean in C?

  1. A static variable inside a function keeps its value between invocations.
  2. A static global variable or a function is "seen" only in the file it's declared in

(1) is the more foreign topic if you're a newbie, so here's an example:

#include <stdio.h>

void foo()
{
    int a = 10;
    static int sa = 10;

    a += 5;
    sa += 5;

    printf("a = %d, sa = %d\n", a, sa);
}


int main()
{
    int i;

    for (i = 0; i < 10; ++i)
        foo();
}

This prints:

a = 15, sa = 15
a = 15, sa = 20
a = 15, sa = 25
a = 15, sa = 30
a = 15, sa = 35
a = 15, sa = 40
a = 15, sa = 45
a = 15, sa = 50
a = 15, sa = 55
a = 15, sa = 60

This is useful for cases where a function needs to keep some state between invocations, and you don't want to use global variables. Beware, however, this feature should be used very sparingly - it makes your code not thread-safe and harder to understand.

(2) Is used widely as an "access control" feature. If you have a .c file implementing some functionality, it usually exposes only a few "public" functions to users. The rest of its functions should be made static, so that the user won't be able to access them. This is encapsulation, a good practice.

Quoting Wikipedia:

In the C programming language, static is used with global variables and functions to set their scope to the containing file. In local variables, static is used to store the variable in the statically allocated memory instead of the automatically allocated memory. While the language does not dictate the implementation of either type of memory, statically allocated memory is typically reserved in data segment of the program at compile time, while the automatically allocated memory is normally implemented as a transient call stack.

And to answer your second question, it's not like in C#.

In C++, however, static is also used to define class attributes (shared between all objects of the same class) and methods. In C there are no classes, so this feature is irrelevant.

How to change current Theme at runtime in Android

This had no effect for me:

public void changeTheme(int newTheme) {
    setTheme(newTheme);
    recreate();
}

But this worked:

int theme = R.style.default;

protected void onCreate(Bundle savedInstanceState) {
    setTheme(this.theme);
    super.onCreate(savedInstanceState);
}

public void changeTheme(int newTheme) {
    this.theme = newTheme;
    recreate();
}

How to solve the memory error in Python

Assuming your example text is representative of all the text, one line would consume about 75 bytes on my machine:

In [3]: sys.getsizeof('usedfor zipper fasten_coat')
Out[3]: 75

Doing some rough math:

75 bytes * 8,000,000 lines / 1024 / 1024 = ~572 MB

So roughly 572 meg to store the strings alone for one of these files. Once you start adding in additional, similarly structured and sized files, you'll quickly approach your virtual address space limits, as mentioned in @ShadowRanger's answer.

If upgrading your python isn't feasible for you, or if it only kicks the can down the road (you have finite physical memory after all), you really have two options: write your results to temporary files in-between loading in and reading the input files, or write your results to a database. Since you need to further post-process the strings after aggregating them, writing to a database would be the superior approach.

Center align a column in twitter bootstrap

The question is correctly answered here Center a column using Twitter Bootstrap 3

For odd rows: i.e., col-md-7 or col-large-9 use this

Add col-centered to the column you want centered.

<div class="col-lg-11 col-centered">    

And add this to your stylesheet:

.col-centered{
float: none;
margin: 0 auto;
}

For even rows: i.e., col-md-6 or col-large-10 use this

Simply use bootstrap 3's offset col class. i.e.,

<div class="col-lg-10 col-lg-offset-1">

Android: How to set password property in an edit text?

Password.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);

This one works for me.
But you have to look at Octavian Damiean's comment, he's right.

What is Node.js?

The closures are a way to execute code in the context it was created in.

What this means for concurency is that you can define variables, then initiate a nonblocking I/O function, and send it an anonymous function for its callback.

When the task is complete, the callback function will execute in the context with the variables, this is the closure.

The reason closures are so good for writing applications with nonblocking I/O is that it's very easy to manage the context of functions executing asynchronously.

Dump a NumPy array into a csv file

numpy.savetxt saves an array to a text file.

import numpy
a = numpy.asarray([ [1,2,3], [4,5,6], [7,8,9] ])
numpy.savetxt("foo.csv", a, delimiter=",")

Wait one second in running program

I feel like all that was wrong here was the order, Selçuklu wanted the app to wait for a second before filling in the grid, so the Sleep command should have come before the fill command.

    System.Threading.Thread.Sleep(1000);
    dataGridView1.Rows[x1].Cells[y1].Style.BackColor = System.Drawing.Color.Red;

React: Expected an assignment or function call and instead saw an expression

Expected an assignment or function call and instead saw an expression.

I had this similar error with this code:

const mapStateToProps = (state) => {
    players: state
}

To correct all I needed to do was add parenthesis around the curved brackets

const mapStateToProps = (state) => ({
    players: state
});

Uncaught SyntaxError: Unexpected token with JSON.parse

Let's say you know it's valid JSON but your are still getting this...

In that case it's likely that there are hidden/special characters in the string from whatever source your getting them. When you paste into a validator, they are lost - but in the string they are still there. Those chars, while invisible, will break JSON.parse()

If s is your raw JSON, then clean it up with:

// preserve newlines, etc - use valid JSON
s = s.replace(/\\n/g, "\\n")  
               .replace(/\\'/g, "\\'")
               .replace(/\\"/g, '\\"')
               .replace(/\\&/g, "\\&")
               .replace(/\\r/g, "\\r")
               .replace(/\\t/g, "\\t")
               .replace(/\\b/g, "\\b")
               .replace(/\\f/g, "\\f");
// remove non-printable and other non-valid JSON chars
s = s.replace(/[\u0000-\u0019]+/g,""); 
var o = JSON.parse(s);

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_

Java difference between FileWriter and BufferedWriter

From the Java API specification:

FileWriter

Convenience class for writing character files. The constructors of this class assume that the default character encoding and the default byte-buffer size are acceptable.

BufferedWriter

Write text to a character-output stream, buffering characters so as to provide for the efficient writing of single characters, arrays, and strings.

JSON encode MySQL results

One more option using FOR loop:

 $sth = mysql_query("SELECT ...");
 for($rows = array(); $row = mysql_fetch_assoc($sth); $rows[] = $row);
 print json_encode($rows);

The only disadvantage is that loop for is slower then e.g. while or especially foreach

How to set background color of a button in Java GUI?

Check out JButton documentation. Take special attention to setBackground and setForeground methods inherited from JComponent.

Something like:

for(int i=1;i<=9;i++)
{
    JButton btn = new JButton(String.valueOf(i));
    btn.setBackground(Color.BLACK);
    btn.setForeground(Color.GRAY);
    p3.add(btn);
}

Converting String to Cstring in C++

vector<char> toVector( const std::string& s ) {
  string s = "apple";  
  vector<char> v(s.size()+1);
  memcpy( &v.front(), s.c_str(), s.size() + 1 );
  return v;
}
vector<char> v = toVector(std::string("apple"));

// what you were looking for (mutable)
char* c = v.data();

.c_str() works for immutable. The vector will manage the memory for you.

SQL how to check that two tables has exactly the same data?

We can compare data from two tables of DB2 tables using the below simple query,

Step 1:- Select which all columns we need to compare from table (T1) of schema(S)

     SELECT T1.col1,T1.col3,T1.col5 from S.T1

Step 2:- Use 'Minus' keyword for comparing 2 tables.

Step 3:- Select which all columns we need to compare from table (T2) of schema(S)

     SELECT T2.col1,T2.col3,T2.col5 from S.T1

END result:

     SELECT T1.col1,T1.col3,T1.col5 from S.T1
     MINUS 
     SELECT T2.col1,T2.col3,T2.col5 from S.T1;

If the query returns no rows then the data is exactly the same.

HTML img scaling

The best way I know how to do this, is:

1) set overflow to scroll and that way the image would stay in but you can scroll to see it instead

2) upload a smaller image. Now there are plenty of programs out there when uploading (you'll need something like PHP or .net to do this btw) you can have it auto scale.

3) Living with it and setting the width and height, this although will make it look distorted but the right size will still result in the user having to download the full-sized image.

Good luck!

Good Java graph algorithm library?

If you were using JGraph, you should give a try to JGraphT which is designed for algorithms. One of its features is visualization using the JGraph library. It's still developed, but pretty stable. I analyzed the complexity of JGraphT algorithms some time ago. Some of them aren't the quickest, but if you're going to implement them on your own and need to display your graph, then it might be the best choice. I really liked using its API, when I quickly had to write an app that was working on graph and displaying it later.

Centering in CSS Grid

I know this question is a couple years old, but I am surprised to find that no one suggested:

   text-align: center;

this is a more universal property than justify-content, and is definitely not unique to grid, but I find that when dealing with text, which is what this question specifically asks about, that it aligns text to the center with-out affecting the space between grid items, or the vertical centering. It centers text horizontally where its stands on its vertical axis. I also find it to remove a layer of complexity that justify-content and align-items adds. justify-content and align-items affects the entire grid item or items, text-align centers the text without affecting the container it is in. Hope this helps.

How to display images from a folder using php - PHP

You have two ways to do that:

METHOD 1. The secure way.

Put the images on /www/htdocs/

<?php
    $www_root = 'http://localhost/images';
    $dir = '/var/www/images';
    $file_display = array('jpg', 'jpeg', 'png', 'gif');

    if ( file_exists( $dir ) == false ) {
       echo 'Directory \'', $dir, '\' not found!';
    } else {
       $dir_contents = scandir( $dir );

        foreach ( $dir_contents as $file ) {
           $file_type = strtolower( end( explode('.', $file ) ) );
           if ( ($file !== '.') && ($file !== '..') && (in_array( $file_type, $file_display)) ) {
              echo '<img src="', $www_root, '/', $file, '" alt="', $file, '"/>';
           break;
           }
        }
    }
?>

METHOD 2. Unsecure but more flexible.

Put the images on any directory (apache must have permission to read the file).

<?php
    $dir = '/home/user/Pictures';
    $file_display = array('jpg', 'jpeg', 'png', 'gif');

    if ( file_exists( $dir ) == false ) {
       echo 'Directory \'', $dir, '\' not found!';
    } else {
       $dir_contents = scandir( $dir );

        foreach ( $dir_contents as $file ) {
           $file_type = strtolower( end( explode('.', $file ) ) );
           if ( ($file !== '.') && ($file !== '..') && (in_array( $file_type, $file_display)) ) {
              echo '<img src="file_viewer.php?file=', base64_encode($dir . '/' . $file), '" alt="', $file, '"/>';
           break;
           }
        }
    }
?>

And create another script to read the image file.

<?php
    $filename = base64_decode($_GET['file']);
    // Check the folder location to avoid exploit
    if (dirname($filename) == '/home/user/Pictures')
        echo file_get_contents($filename);
?>

Typescript: How to extend two classes?

Unfortunately typescript does not support multiple inheritance. Therefore there is no completely trivial answer, you will probably have to restructure your program

Here are a few suggestions:

  • If this additional class contains behaviour that many of your subclasses share, it makes sense to insert it into the class hierarchy, somewhere at the top. Maybe you could derive the common superclass of Sprite, Texture, Layer, ... from this class ? This would be a good choice, if you can find a good spot in the type hirarchy. But I would not recommend to just insert this class at a random point. Inheritance expresses an "Is a - relationship" e.g. a dog is an animal, a texture is an instance of this class. You would have to ask yourself, if this really models the relationship between the objects in your code. A logical inheritance tree is very valuable

  • If the additional class does not fit logically into the type hierarchy, you could use aggregation. That means that you add an instance variable of the type of this class to a common superclass of Sprite, Texture, Layer, ... Then you can access the variable with its getter/setter in all subclasses. This models a "Has a - relationship".

  • You could also convert your class into an interface. Then you could extend the interface with all your classes but would have to implement the methods correctly in each class. This means some code redundancy but in this case not much.

You have to decide for yourself which approach you like best. Personally I would recommend to convert the class to an interface.

One tip: Typescript offers properties, which are syntactic sugar for getters and setters. You might want to take a look at this: http://blogs.microsoft.co.il/gilf/2013/01/22/creating-properties-in-typescript/

Rails: Why "sudo" command is not recognized?

sudo is a command for Linux so it cant be used in windows so you will get that error

What is the difference between syntax and semantics in programming languages?

Syntax is about the structure or the grammar of the language. It answers the question: how do I construct a valid sentence? All languages, even English and other human (aka "natural") languages have grammars, that is, rules that define whether or not the sentence is properly constructed.

Here are some C language syntax rules:

  • separate statements with a semi-colon
  • enclose the conditional expression of an IF statement inside parentheses
  • group multiple statements into a single statement by enclosing in curly braces
  • data types and variables must be declared before the first executable statement (this feature has been dropped in C99. C99 and latter allow mixed type declarations.)

Semantics is about the meaning of the sentence. It answers the questions: is this sentence valid? If so, what does the sentence mean? For example:

x++;                  // increment
foo(xyz, --b, &qrs);  // call foo

are syntactically valid C statements. But what do they mean? Is it even valid to attempt to transform these statements into an executable sequence of instructions? These questions are at the heart of semantics.

Consider the ++ operator in the first statement. First of all, is it even valid to attempt this?

  • If x is a float data type, this statement has no meaning (according to the C language rules) and thus it is an error even though the statement is syntactically correct.
  • If x is a pointer to some data type, the meaning of the statement is to "add sizeof(some data type) to the value at address x and store the result into the location at address x".
  • If x is a scalar, the meaning of the statement is "add one to the value at address x and store the result into the location at address x".

Finally, note that some semantics cannot be determined at compile-time and must therefore must be evaluated at run-time. In the ++ operator example, if x is already at the maximum value for its data type, what happens when you try to add 1 to it? Another example: what happens if your program attempts to dereference a pointer whose value is NULL?

In summary, syntax is the concept that concerns itself only whether or not the sentence is valid for the grammar of the language . Semantics is about whether or not the sentence has a valid meaning.

Creating a Custom Event

Yes you can do like this :

Creating advanced C# custom events

or

The Simplest C# Events Example Imaginable

public class Metronome
{
    public event TickHandler Tick;
    public EventArgs e = null;
    public delegate void TickHandler(Metronome m, EventArgs e);
    public void Start()
    {
        while (true)
        {
            System.Threading.Thread.Sleep(3000);
            if (Tick != null)
            {
                Tick(this, e);
            }
        }
    }
}
public class Listener
{
    public void Subscribe(Metronome m)
    {
        m.Tick += new Metronome.TickHandler(HeardIt);
    }

    private void HeardIt(Metronome m, EventArgs e)
    {
        System.Console.WriteLine("HEARD IT");
    }
}
class Test
{
    static void Main()
    {
        Metronome m = new Metronome();
        Listener l = new Listener();
        l.Subscribe(m);
        m.Start();
    }
}

How to find the privileges and roles granted to a user in Oracle?

SELECT * 
FROM DBA_ROLE_PRIVS 
WHERE UPPER(GRANTEE) LIKE '%XYZ%';

Check if certain value is contained in a dataframe column in pandas

You can use any:

print any(df.column == 07311954)
True       #true if it contains the number, false otherwise

If you rather want to see how many times '07311954' occurs in a column you can use:

df.column[df.column == 07311954].count()

What is the difference between include and require in Ruby?

  • Ruby require is more like "include" in other languages (such as C). It tells Ruby that you want to bring in the contents of another file. Similar mechanisms in other languages are:

  • Ruby include is an object-oriented inheritance mechanism used for mixins.

There is a good explanation here:

[The] simple answer is that require and include are essentially unrelated.

"require" is similar to the C include, which may cause newbie confusion. (One notable difference is that locals inside the required file "evaporate" when the require is done.)

The Ruby include is nothing like the C include. The include statement "mixes in" a module into a class. It's a limited form of multiple inheritance. An included module literally bestows an "is-a" relationship on the thing including it.

Emphasis added.

Error inflating when extending a class

I think I figured out why this wasn't working. I was only providing a constructor for the case of one parameter 'context' when I should have provided a constructor for the two parameter 'Context, AttributeSet' case. I also needed to give the constructor(s) public access. Here's my fix:

public class GhostSurfaceCameraView extends SurfaceView implements SurfaceHolder.Callback {
        SurfaceHolder mHolder;
        Camera mCamera;

        public GhostSurfaceCameraView(Context context)
        {
            super(context);
            init();
        }
        public GhostSurfaceCameraView(Context context, AttributeSet attrs)
        {
            super(context, attrs);
            init();
        }
        public GhostSurfaceCameraView(Context context, AttributeSet attrs, int defStyle) {
            super(context, attrs, defStyle);
            init();
        }

Set font-weight using Bootstrap classes

In Bootstrap 4:

class="font-weight-bold"

Or:

<strong>text</strong>

How to stop a JavaScript for loop?

I know this is a bit old, but instead of looping through the array with a for loop, it would be much easier to use the method <array>.indexOf(<element>[, fromIndex])

It loops through an array, finding and returning the first index of a value. If the value is not contained in the array, it returns -1.

<array> is the array to look through, <element> is the value you are looking for, and [fromIndex] is the index to start from (defaults to 0).

I hope this helps reduce the size of your code!

Completely remove MariaDB or MySQL from CentOS 7 or RHEL 7

These steps are working on CentOS 6.5 so they should work on CentOS 7 too:

(EDIT - exactly the same steps work for MariaDB 10.3 on CentOS 8)

  1. yum remove mariadb mariadb-server
  2. rm -rf /var/lib/mysql If your datadir in /etc/my.cnf points to a different directory, remove that directory instead of /var/lib/mysql
  3. rm /etc/my.cnf the file might have already been deleted at step 1
  4. Optional step: rm ~/.my.cnf
  5. yum install mariadb mariadb-server

[EDIT] - Update for MariaDB 10.1 on CentOS 7

The steps above worked for CentOS 6.5 and MariaDB 10.

I've just installed MariaDB 10.1 on CentOS 7 and some of the steps are slightly different.

Step 1 would become:

yum remove MariaDB-server MariaDB-client

Step 5 would become:

yum install MariaDB-server MariaDB-client

The other steps remain the same.

How can I declare optional function parameters in JavaScript?

Update

With ES6, this is possible in exactly the manner you have described; a detailed description can be found in the documentation.

Old answer

Default parameters in JavaScript can be implemented in mainly two ways:

function myfunc(a, b)
{
    // use this if you specifically want to know if b was passed
    if (b === undefined) {
        // b was not passed
    }
    // use this if you know that a truthy value comparison will be enough
    if (b) {
        // b was passed and has truthy value
    } else {
        // b was not passed or has falsy value
    }
    // use this to set b to a default value (using truthy comparison)
    b = b || "default value";
}

The expression b || "default value" evaluates the value AND existence of b and returns the value of "default value" if b either doesn't exist or is falsy.

Alternative declaration:

function myfunc(a)
{
    var b;

    // use this to determine whether b was passed or not
    if (arguments.length == 1) {
        // b was not passed
    } else {
        b = arguments[1]; // take second argument
    }
}

The special "array" arguments is available inside the function; it contains all the arguments, starting from index 0 to N - 1 (where N is the number of arguments passed).

This is typically used to support an unknown number of optional parameters (of the same type); however, stating the expected arguments is preferred!

Further considerations

Although undefined is not writable since ES5, some browsers are known to not enforce this. There are two alternatives you could use if you're worried about this:

b === void 0;
typeof b === 'undefined'; // also works for undeclared variables

showDialog deprecated. What's the alternative?

From http://developer.android.com/reference/android/app/Activity.html

public final void showDialog (int id) Added in API level 1

This method was deprecated in API level 13. Use the new DialogFragment class with FragmentManager instead; this is also available on older platforms through the Android compatibility package.

Simple version of showDialog(int, Bundle) that does not take any arguments. Simply calls showDialog(int, Bundle) with null arguments.

Why

  • A fragment that displays a dialog window, floating on top of its activity's window. This fragment contains a Dialog object, which it displays as appropriate based on the fragment's state. Control of the dialog (deciding when to show, hide, dismiss it) should be done through the API here, not with direct calls on the dialog.
  • Here is a nice discussion Android DialogFragment vs Dialog
  • Another nice discussion DialogFragment advantages over AlertDialog

How to solve?

More

Program does not contain a static 'Main' method suitable for an entry point

Project Properties \ Output file -> Select Class Library :)

How to convert a char array to a string?

The string class has a constructor that takes a NULL-terminated C-string:

char arr[ ] = "This is a test";

string str(arr);


//  You can also assign directly to a string.
str = "This is another string";

// or
str = arr;

Image change every 30 seconds - loop

I agree with using frameworks for things like this, just because its easier. I hacked this up real quick, just fades an image out and then switches, also will not work in older versions of IE. But as you can see the code for the actual fade is much longer than the JQuery implementation posted by KARASZI István.

function changeImage() {
    var img = document.getElementById("img");
    img.src = images[x];
    x++;        
    if(x >= images.length) {
        x = 0;
    } 
    fadeImg(img, 100, true);
    setTimeout("changeImage()", 30000);
}

function fadeImg(el, val, fade) {
    if(fade === true) {
        val--;
    } else {
        val ++;
    }       
    if(val > 0 && val < 100) {
        el.style.opacity = val / 100;
        setTimeout(function(){ fadeImg(el, val, fade); }, 10);
    }
}

var images = [], x = 0;
images[0] = "image1.jpg";
images[1] = "image2.jpg";
images[2] = "image3.jpg";
setTimeout("changeImage()", 30000);

Excel VBA Run Time Error '424' object required

Private Sub CommandButton1_Click()

    Workbooks("Textfile_Receiving").Sheets("menu").Range("g1").Value = PROV.Text
    Workbooks("Textfile_Receiving").Sheets("menu").Range("g2").Value = MUN.Text
    Workbooks("Textfile_Receiving").Sheets("menu").Range("g3").Value = CAT.Text
    Workbooks("Textfile_Receiving").Sheets("menu").Range("g4").Value = Label5.Caption

    Me.Hide

    Run "filename"

End Sub

Private Sub MUN_Change()
    Dim r As Integer
    r = 2

    While Range("m" & CStr(r)).Value <> ""
        If Range("m" & CStr(r)).Value = MUN.Text Then
        Label5.Caption = Range("n" & CStr(r)).Value
        End If
        r = r + 1
    Wend

End Sub

Private Sub PROV_Change()
    If PROV.Text = "LAGUNA" Then
        MUN.Text = ""
        MUN.RowSource = "Menu!M26:M56"
    ElseIf PROV.Text = "CAVITE" Then
        MUN.Text = ""
        MUN.RowSource = "Menu!M2:M25"
    ElseIf PROV.Text = "QUEZON" Then
        MUN.Text = ""
        MUN.RowSource = "Menu!M57:M97"
    End If
End Sub

SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data

JSON.parse() doesn't recognize That data as string. For example {objAskGrant:"Yes",objPass:"asdfasdf",objNameSurname:"asdfasdf adfasdf",objEmail:"[email protected]",objGsm:3241234123,objAdres:"asdfasdf",objTerms:"CheckIsValid"}

Which is like this: JSON.parse({objAskGrant:"Yes",objPass:"asdfasdf",objNameSurname:"asdfasdf adfasdf",objEmail:"[email protected]",objGsm:3241234123,objAdres:"asdfasdf",objTerms:"CheckIsValid"}); That will output SyntaxError: missing " ' " instead of "{" on line...

So correctly wrap all data like this: '{"objAskGrant":"Yes","objPass":"asdfasdf","objNameSurname":"asdfasdf adfasdf","objEmail":"[email protected]","objGsm":3241234123,"objAdres":"asdfasdf","objTerms":"CheckIsValid"}' Which works perfectly well for me.

And not like this: "{"objAskGrant":"Yes","objPass":"asdfasdf","objNameSurname":"asdfasdf adfasdf","objEmail":"[email protected]","objGsm":3241234123,"objAdres":"asdfasdf","objTerms":"CheckIsValid"}" Which give the present error you are experiencing.

How do I remove all non-ASCII characters with regex and Notepad++?

Another good trick is to go into UTF8 mode in your editor so that you can actually see these funny characters and delete them yourself.

afxwin.h file is missing in VC++ Express Edition

Including the header afxwin.h signalizes use of MFC. The following instructions (based on those on CodeProject.com) could help to get MFC code compiling:

  1. Download and install the Windows Driver Kit.

  2. Select menu Tools > Options… > Projects and Solutions > VC++ Directories.

  3. In the drop-down menu Show directories for select Include files.

  4. Add the following paths (replace $(WDK_directory) with the directory where you installed Windows Driver Kit in the first step):

    $(WDK_directory)\inc\mfc42
    $(WDK_directory)\inc\atl30
    

  5. In the drop-down menu Show directories for select Library files and add (replace $(WDK_directory) like before):

    $(WDK_directory)\lib\mfc\i386
    $(WDK_directory)\lib\atl\i386
    

  6. In the $(WDK_directory)\inc\mfc42\afxwin.inl file, edit the following lines (starting from 1033):

    _AFXWIN_INLINE CMenu::operator==(const CMenu& menu) const
        { return ((HMENU) menu) == m_hMenu; }
    _AFXWIN_INLINE CMenu::operator!=(const CMenu& menu) const
        { return ((HMENU) menu) != m_hMenu; }
    

    to

    _AFXWIN_INLINE BOOL CMenu::operator==(const CMenu& menu) const
        { return ((HMENU) menu) == m_hMenu; }
    _AFXWIN_INLINE BOOL CMenu::operator!=(const CMenu& menu) const
        { return ((HMENU) menu) != m_hMenu; }
    

    In other words, add BOOL after _AFXWIN_INLINE.

Android error: Failed to install *.apk on device *: timeout

I get this a lot. I'm on a Galaxy S too. I unplug the cable from the phone, plug it back in and try launching the app again from Eclipse, and it usually does the trick. Eclipse seems to lose the connection to the phone occasionally but this seems to kick it back to life.

String vs. StringBuilder

If you're doing a lot of string concatenation, use a StringBuilder. When you concatenate with a String, you create a new String each time, using up more memory.

Alex

jQuery Find and List all LI elements within a UL within a specific DIV

$('li[rel=7]').siblings().andSelf();

// or:

$('li[rel=7]').parent().children();

Now that you added that comment explaining that you want to "form an array of rels per column", you should do this:

var rels = [];

$('ul').each(function() {
    var localRels = [];

    $(this).find('li').each(function(){
        localRels.push( $(this).attr('rel') );
    });

    rels.push(localRels);
});

Language Books/Tutorials for popular languages

Erlang

I've found Programming Erlang to be an excellent book for learning Erlang. It's written by the guy who created the language, and covers both basic and advanced topics very well. It has some great examples, too.

onclick open window and specific size

<a href="/index2.php?option=com_jumi&amp;fileid=3&amp;Itemid=11"
   onclick="window.open(this.href,'targetWindow',
                                   `toolbar=no,
                                    location=no,
                                    status=no,
                                    menubar=no,
                                    scrollbars=yes,
                                    resizable=yes,
                                    width=SomeSize,
                                    height=SomeSize`);
 return false;">Popup link</a>

Where width and height are pixels without units (width=400 not width=400px).

In most browsers it will not work if it is not written without line breaks, once the variables are setup have everything in one line:

<a href="/index2.php?option=com_jumi&amp;fileid=3&amp;Itemid=11" onclick="window.open(this.href,'targetWindow','toolbar=no,location=no,status=no,menubar=no,scrollbars=yes,resizable=yes,width=SomeSize,height=SomeSize'); return false;">Popup link</a> 

The cause of "bad magic number" error when loading a workspace and how to avoid it?

I got that error when I accidentally used load() instead of source() or readRDS().

Using app.config in .Net Core

  1. You can use Microsoft.Extensions.Configuration API with any .NET Core app, not only with ASP.NET Core app. Look into sample provided in the link, that shows how to read configs in the console app.

  2. In most cases, the JSON source (read as .json file) is the most suitable config source.

    Note: don't be confused when someone says that config file should be appsettings.json. You can use any file name, that is suitable for you and file location may be different - there are no specific rules.

    But, as the real world is complicated, there are a lot of different configuration providers:

    • File formats (INI, JSON, and XML)
    • Command-line arguments
    • Environment variables

    and so on. You even could use/write a custom provider.

  3. Actually, app.config configuration file was an XML file. So you can read settings from it using XML configuration provider (source on github, nuget link). But keep in mind, it will be used only as a configuration source - any logic how your app behaves should be implemented by you. Configuration Provider will not change 'settings' and set policies for your apps, but only read data from the file.

A simple algorithm for polygon intersection

I understand the original poster was looking for a simple solution, but unfortunately there really is no simple solution.

Nevertheless, I've recently created an open-source freeware clipping library (written in Delphi, C++ and C#) which clips all kinds of polygons (including self-intersecting ones). This library is pretty simple to use: http://sourceforge.net/projects/polyclipping/ .

Regex to match string containing two names in any order

Explanation of command that i am going to write:-

. means any character, digit can come in place of .

* means zero or more occurrences of thing written just previous to it.

| means 'or'.

So,

james.*jack

would search james , then any number of character until jack comes.

Since you want either jack.*james or james.*jack

Hence Command:

jack.*james|james.*jack

Sleep function in Windows, using C

SleepEx function (see http://msdn.microsoft.com/en-us/library/ms686307.aspx) is the best choise if your program directly or indirectly creates windows (for example use some COM objects). In the simples cases you can also use Sleep.

What does Ruby have that Python doesn't, and vice versa?

Some others from:

http://www.ruby-lang.org/en/documentation/ruby-from-other-languages/to-ruby-from-python/

(If I have misintrepreted anything or any of these have changed on the Ruby side since that page was updated, someone feel free to edit...)

Strings are mutable in Ruby, not in Python (where new strings are created by "changes").

Ruby has some enforced case conventions, Python does not.

Python has both lists and tuples (immutable lists). Ruby has arrays corresponding to Python lists, but no immutable variant of them.

In Python, you can directly access object attributes. In Ruby, it's always via methods.

In Ruby, parentheses for method calls are usually optional, but not in Python.

Ruby has public, private, and protected to enforce access, instead of Python’s convention of using underscores and name mangling.

Python has multiple inheritance. Ruby has "mixins."

And another very relevant link:

http://c2.com/cgi/wiki?PythonVsRuby

Which, in particular, links to another good one by Alex Martelli, who's been also posting a lot of great stuff here on SO:

http://groups.google.com/group/comp.lang.python/msg/028422d707512283

Choosing the correct upper and lower HSV boundaries for color detection with`cv::inRange` (OpenCV)

To find the HSV value of Green, try following commands in Python terminal

green = np.uint8([[[0,255,0 ]]])
hsv_green = cv2.cvtColor(green,cv2.COLOR_BGR2HSV)
print hsv_green
[[[ 60 255 255]]]

Gradle build without tests

the different way to disable test tasks in the project is:

tasks.withType(Test) {enabled = false}

this behavior needed sometimes if you want to disable tests in one of a project(or the group of projects).

This way working for the all kind of test task, not just a java 'tests'. Also, this way is safe. Here's what I mean let's say: you have a set of projects in different languages: if we try to add this kind of record in main build.gradle:

 subprojects{
 .......
 tests.enabled=false
 .......
}

we will fail in a project when if we have no task called tests

How do I create an average from a Ruby array?

You could try something like the following:

a = [1,2,3,4,5]
# => [1, 2, 3, 4, 5]
(a.sum/a.length).to_f
# => 3.0

I got error "The DELETE statement conflicted with the REFERENCE constraint"

Have you considered applying ON DELETE CASCADE where relevant?

How to create multidimensional array

I've created an npm module to do this with some added flexibility:

// create a 3x3 array
var twodimensional = new MultiDimensional([3, 3])

// create a 3x3x4 array
var threedimensional = new MultiDimensional([3, 3, 4])

// create a 4x3x4x2 array
var fourdimensional = new MultiDimensional([4, 3, 4, 2])

// etc...

You can also initialize the positions with any value:

// create a 3x4 array with all positions set to 0
var twodimensional = new MultiDimensional([3, 4], 0)

// create a 3x3x4 array with all positions set to 'Default String'
var threedimensionalAsStrings = new MultiDimensional([3, 3, 4], 'Default String')

Or more advanced:

// create a 3x3x4 array with all positions set to a unique self-aware objects.
var threedimensional = new MultiDimensional([3, 3, 4], function(position, multidimensional) {
    return {
        mydescription: 'I am a cell at position ' + position.join(),
        myposition: position,
        myparent: multidimensional
    }
})

Get and set values at positions:

// get value
threedimensional.position([2, 2, 2])

// set value
threedimensional.position([2, 2, 2], 'New Value')

Changing minDate and maxDate on the fly using jQuery DatePicker

For from / to date, here is how I implemented restricting the dates based on the date entered in the other datepicker. Works pretty good:

function activateDatePickers() {
    $("#aDateFrom").datepicker({
        onClose: function() {
            $("#aDateTo").datepicker(
                    "change",
                    { minDate: new Date($('#aDateFrom').val()) }
            );
        }
    });
    $("#aDateTo").datepicker({
        onClose: function() {
            $("#aDateFrom").datepicker(
                    "change",
                    { maxDate: new Date($('#aDateTo').val()) }
            );
        }
    });
}

How to compile and run a C/C++ program on the Android system

If you want to compile and run Java/C/C++ apps directly on your Android device, I recommend the Terminal IDE environment from Google Play. It's a very slick package to develop and compile Android APKs, Java, C and C++ directly on your device. The interface is all command line and "vi" based, so it has real Linux feel. It comes with the gnu C/C++ implementation.

Additionally, there is a telnet and telnet server application built in, so you can do all the programming with your PC and big keyboard, but working on the device. No root permission is needed.

std::queue iteration

If you need to iterate over a queue then you need something more than a queue. The point of the standard container adapters is to provide a minimal interface. If you need to do iteration as well, why not just use a deque (or list) instead?

Can't get Python to import from a different folder

My preferred way is to have __init__.py on every directory that contains modules that get used by other modules, and in the entry point, override sys.path as below:

def get_path(ss):
  return os.path.join(os.path.dirname(__file__), ss)
sys.path += [
  get_path('Server'), 
  get_path('Models')
]

This makes the files in specified directories visible for import, and I can import user from Server.py.

How to return a value from a Form in C#?

First you have to define attribute in form2(child) you will update this attribute in form2 and also from form1(parent) :

 public string Response { get; set; }

 private void OkButton_Click(object sender, EventArgs e)
 {
    Response = "ok";
 }

 private void CancelButton_Click(object sender, EventArgs e)
 {
    Response = "Cancel";
 }

Calling of form2(child) from form1(parent):

  using (Form2 formObject= new Form2() )
  {
     formObject.ShowDialog();

      string result = formObject.Response; 
      //to update response of form2 after saving in result
      formObject.Response="";

      // do what ever with result...
      MessageBox.Show("Response from form2: "+result); 
  }

Editing hosts file to redirect url?

No, but you could open a web server at, for example, 127.0.0.77 and use it to check if the Request URI is "/welcome.aspx"... If yes redirect to google, if not load the original site.

127.0.0.77      mysite.com

ng if with angular for string contains

Do checks like that in a controller function. Your HTML should be easy-to-read markup without logic.

Controller:

angular.module("myApp")
.controller("myController",function(){
    var self = this;

    self.select = { /* ... */ };

    self.showFoo = function() {
        //Checks if self.select.name contains the character '?'
        return self.select.name.indexOf('?') != -1;
    }
});

Page example:

<div ng-app="myApp" ng-controller="myController as vm">
    <p ng-show="vm.showFoo()">Bar</p>
</div>