SyntaxFix

Programs & Examples On #Rescale

Java image resize, maintain aspect ratio

 
public class ImageTransformation {

public static final String PNG = "png";

public static byte[] resize(FileItem fileItem, int width, int height) {

    try {
        ResampleOp resampleOp = new ResampleOp(width, height);
        BufferedImage scaledImage = resampleOp.filter(ImageIO.read(fileItem.getInputStream()), null);

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        ImageIO.write(scaledImage, PNG, baos);

        return baos.toByteArray();
    } catch (Exception ex) {
        throw new MapsException("An error occured during image resizing.", ex);
    }

}

public static byte[] resizeAdjustMax(FileItem fileItem, int maxWidth, int maxHeight) {

    try {
        BufferedInputStream bis = new BufferedInputStream(fileItem.getInputStream());  
        BufferedImage bufimg = ImageIO.read(bis);   

        //check size of image 
        int img_width = bufimg.getWidth();
        int img_height = bufimg.getHeight();
        if(img_width > maxWidth || img_height > maxHeight) {
            float factx = (float) img_width / maxWidth;
            float facty = (float) img_height / maxHeight;
            float fact = (factx>facty) ? factx : facty;
            img_width = (int) ((int) img_width / fact);
            img_height = (int) ((int) img_height / fact);
        }

        return resize(fileItem,img_width, img_height);

    } catch (Exception ex) {
        throw new MapsException("An error occured during image resizing.", ex);
    }

}

}

What's the proper value for a checked attribute of an HTML checkbox?

I think this may help:

First read all the specs from Microsoft and W3.org.
You'd see that the setting the actual element of a checkbox needs to be done on the ELEMENT PROPERTY, not the UI or attribute.
$('mycheckbox')[0].checked

Secondly, you need to be aware that the checked attribute RETURNS a string "true", "false"
Why is this important? Because you need to use the correct Type. A string, not a boolean. This also important when parsing your checkbox.
$('mycheckbox')[0].checked = "true"

if($('mycheckbox')[0].checked === "true"){ //do something }

You also need to realize that the "checked" ATTRIBUTE is for setting the value of the checkbox initially. This doesn't do much once the element is rendered to the DOM. Picture this working when the webpage loads and is initially parsed.
I'll go with IE's preference on this one: <input type="checkbox" checked="checked"/>

Lastly, the main aspect of confusion for a checkbox is that the checkbox UI element is not the same as the element's property value. They do not correlate directly. If you work in .net, you'll discover that the user "checking" a checkbox never reflects the actual bool value passed to the controller. To set the UI, I use both $('mycheckbox').val(true); and $('mycheckbox').attr('checked', 'checked');

In short, for a checked checkbox you need:
Initial DOM: <input type="checkbox" checked="checked">
Element Property: $('mycheckbox')[0].checked = "true";
UI: $('mycheckbox').val(true); and $('mycheckbox').attr('checked', 'checked');

What does "Object reference not set to an instance of an object" mean?

In a nutshell it means.. You are trying to access an object without instantiating it.. You might need to use the "new" keyword to instantiate it first i.e create an instance of it.

For eg:

public class MyClass
{
   public int Id {get; set;}
}

MyClass myClass;

myClass.Id = 0; <----------- An error will be thrown here.. because myClass is null here...

You will have to use:

myClass = new MyClass();
myClass.Id = 0;

Hope I made it clear..

Display the current time and date in an Android application

From How to get full date with correct format?:

Please, use

android.text.format.DateFormat.getDateFormat(Context context)
android.text.format.DateFormat.getTimeFormat(Context context)

to get valid time and date formats in sense of current user settings (12/24 time format, for example).

import android.text.format.DateFormat;

private void some() {
    final Calendar t = Calendar.getInstance();
    textView.setText(DateFormat.getTimeFormat(this/*Context*/).format(t.getTime()));
}

Git fails when pushing commit to github

The Problem to push mostly is because of the size of the files that need to be pushed. I was trying to push some libraries of just size 2 mb, then too the push was giving error of RPC with result 7. The line is of 4 mbps and is working fine. Some subsequent tries to the push got me success. If such error comes, wait for few minutes and keep on trying.

I also found out that there are some RPC failures if the github is down or is getting unstable network at their side.

So keeping up trying after some intervals is the only option!

Get Selected value of a Combobox

You can use the below change event to which will trigger when the combobox value will change.

Private Sub ComboBox1_Change()
'your code here
End Sub

Also you can get the selected value using below

ComboBox1.Value

Subset of rows containing NA (missing) values in a chosen column of a data frame

Prints all the rows with NA data:

tmp <- data.frame(c(1,2,3),c(4,NA,5));
tmp[round(which(is.na(tmp))/ncol(tmp)),]

Remove Object from Array using JavaScript

The clean solution would be to use Array.filter:

var filtered = someArray.filter(function(el) { return el.Name != "Kristian"; });

The problem with this is that it does not work on IE < 9. However, you can include code from a Javascript library (e.g. underscore.js) that implements this for any browser.

Regex for allowing alphanumeric,-,_ and space

 
var string = 'test- _ 0Test';
string.match(/^[-_ a-zA-Z0-9]+$/)

How do I format a date in Jinja2?

You can use it like this in jinja template {{ row.session_start_date_time.strftime('%d-%m-%Y %H:%M:%S')}}

In this code the field name is row.session_start_date_time.

How to display gpg key details without importing it?

To get the key IDs (8 bytes, 16 hex digits), this is the command which worked for me in GPG 1.4.16, 2.1.18 and 2.2.19:

gpg --list-packets <key.asc | awk '$1=="keyid:"{print$2}'

To get some more information (in addition to the key ID):

gpg --list-packets <key.asc

To get even more information:

gpg --list-packets -vvv --debug 0x2 <key.asc

The command

gpg --dry-run --import <key.asc

also works in all 3 versions, but in GPG 1.4.16 it prints only a short (4 bytes, 8 hex digits) key ID, so it's less secure to identify keys.

Some commands in other answers (e.g. gpg --show-keys, gpg --with-fingerprint, gpg --import --import-options show-only) don't work in some of the 3 GPG versions above, thus they are not portable when targeting multiple versions of GPG.

How to get option text value using AngularJS?

Instead of ng-options="product as product.label for product in products"> in the select element, you can even use this:

<option ng-repeat="product in products" value="{{product.label}}">{{product.label}}

which works just fine as well.

How to position two divs horizontally within another div

When you float sub-left and sub-right they no longer take up any space within sub-title. You need to add another div with style = "clear: both" beneath them to expand the containing div or they appear below it.

HTML:

<div id="sub-title">
   <div id="sub-left">
      sub-left
   </div>
   <div id="sub-right">
      sub-right
   </div>
   <div class="clear-both"></div>
</div>

CSS:

#sub-left {
   float: left;
}
#sub-right {
   float: right;
}
.clear-both {
   clear: both;
}

Check if string is upper, lower, or mixed case in Python

I want to give a shoutout for using re module for this. Specially in the case of case sensitivity.

We use the option re.IGNORECASE while compiling the regex for use of in production environments with large amounts of data.

>>> import re
>>> m = ['isalnum','isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper', 'ISALNUM', 'ISALPHA', 'ISDIGIT', 'ISLOWER', 'ISSPACE', 'ISTITLE', 'ISUPPER']
>>>
>>>
>>> pattern = re.compile('is')
>>>
>>> [word for word in m if pattern.match(word)]
['isalnum', 'isalpha', 'isdigit', 'islower', 'isspace', 'istitle', 'isupper']

However try to always use the in operator for string comparison as detailed in this post

faster-operation-re-match-or-str

Also detailed in the one of the best books to start learning python with

idiomatic-python

Horizontal Scroll Table in Bootstrap/CSS

@Ciwan. You're right. The table goes to full width (much too wide). Not a good solution. Better to do this:

css:

.scrollme {
    overflow-x: auto;
}

html:

<div class="scrollme">                        
  <table class="table table-responsive"> ...
  </table>
</div>

Edit: changing scroll-y to scroll-x

What is the difference between DTR/DSR and RTS/CTS flow control?
  • DTR - Data Terminal Ready
  • DSR - Data Set Ready
  • RTS - Request To Send
  • CTS - Clear To Send

There are multiple ways of doing things because there were never any protocols built into the standards. You use whatever ad-hoc "standard" your equipment implements.

Just based on the names, RTS/CTS would seem to be a natural fit. However, it's backwards from the needs that developed over time. These signals were created at a time when a terminal would batch-send a screen full of data, but the receiver might not be ready, thus the need for flow control. Later the problem would be reversed, as the terminal couldn't keep up with data coming from the host, but the RTS/CTS signals go the wrong direction - the interface isn't orthogonal, and there's no corresponding signals going the other way. Equipment makers adapted as best they could, including using the DTR and DSR signals.

EDIT

To add a bit more detail, its a two level hierarchy so "officially" both must happen for communication to take place. The behavior is defined in the original CCITT (now ITU-T) standard V.28.

enter image description here

The DCE is a modem connecting between the terminal and telephone network. In the telephone network was another piece of equipment which split off to the data network, eg. X.25.

The modem has three states: Powered off, Ready (Data Set Ready is true), and connected (Data Carrier Detect)

The terminal can't do anything until the modem is connected.

When the modem wants to send data, it raises RTS and the modem grants the request with CTS. The modem lowers CTS when its internal buffer is full.

So nostalgic!

What does the restrict keyword mean in C++?

There's no such keyword in C++. List of C++ keywords can be found in section 2.11/1 of C++ language standard. restrict is a keyword in C99 version of C language and not in C++.

Take a screenshot via a Python script on Linux

There is a python package for this Autopy

The bitmap module can to screen grabbing (bitmap.capture_screen) It is multiplateform (Windows, Linux, Osx).

Server Client send/receive simple text

CLIENT

namespace SocketKlient

{
    class Program

    {
        static Socket Klient;
        static IPEndPoint endPoint;
        static void Main(string[] args)
        {
            Klient = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            string command;
            Console.WriteLine("Write IP address");
            command = Console.ReadLine();
            IPAddress Address;
            while(!IPAddress.TryParse(command, out Address)) 
            {
                Console.WriteLine("wrong IP format");
                command = Console.ReadLine();
            }
            Console.WriteLine("Write port");
            command = Console.ReadLine();

            int port;
            while (!int.TryParse(command, out port) && port > 0)
            {
                Console.WriteLine("Wrong port number");
                command = Console.ReadLine();
            }
            endPoint = new IPEndPoint(Address, port); 
            ConnectC(Address, port);
            while(Klient.Connected)
            {
                Console.ReadLine();
                Odesli();
            }
        }

        public static void ConnectC(IPAddress ip, int port)
        {
            IPEndPoint endPoint = new IPEndPoint(ip, port);
            Console.WriteLine("Connecting...");
            try
            {
                Klient.Connect(endPoint);
                Console.WriteLine("Connected!");
            }
            catch
            {
                Console.WriteLine("Connection fail!");
                return; 
            }
            Task t = new Task(WaitForMessages); 
            t.Start(); 
        }

        public static void SendM()
        {
            string message = "Actualy date is " + DateTime.Now; 
            byte[] buffer = Encoding.UTF8.GetBytes(message);
            Console.WriteLine("Sending: " + message);
            Klient.Send(buffer);
        }

        public static void WaitForMessages()
        {
            try
            {
                while (true)
                {
                    byte[] buffer = new byte[64]; 
                    Console.WriteLine("Waiting for answer");
                    Klient.Receive(buffer, 0, buffer.Length, 0); 

                    string message = Encoding.UTF8.GetString(buffer); 
                    Console.WriteLine("Answer: " + message); 
                }
            }
            catch
            {
                Console.WriteLine("Disconnected");
            }
        }
    }
}

How to set level logging to DEBUG in Tomcat?

JULI logging levels for Tomcat

SEVERE - Serious failures

WARNING - Potential problems

INFO - Informational messages

CONFIG - Static configuration messages

FINE - Trace messages

FINER - Detailed trace messages

FINEST - Highly detailed trace messages

You can find here more https://documentation.progress.com/output/ua/OpenEdge_latest/index.html#page/pasoe-admin/tomcat-logging.html

How to pass data from child component to its parent in ReactJS?

You can even avoid the function at the parent updating the state directly

In Parent Component: 

render(){
 return(<Child sendData={ v => this.setState({item: v}) } />);
}

In the Child Component: 

demoMethod(){
   this.props.sendData(value);
}

File Upload with Angular Material

Another hacked solution, though might be a little cleaner by implementing a Proxy button:

HTML:

<input id="fileInput" type="file">
<md-button class="md-raised" ng-click="upload()">
  <label>AwesomeButtonName</label>
</md-button>

JS:

app.controller('NiceCtrl', function ( $scope) {
  $scope.upload = function () {
    angular.element(document.querySelector('#fileInput')).click();
  };
};

How to change MySQL data directory?

If you want to do this programmatically (no manual text entry with gedit) here's a version for a Dockerfile based on user1341296's answer above:

FROM spittet/ruby-mysql
MAINTAINER [email protected]

RUN cp -R -p /var/lib/mysql /dev/shm && \
    rm -rf /var/lib/mysql && \
    sed -i -e 's,/var/lib/mysql,/dev/shm/mysql,g' /etc/mysql/my.cnf && \
    /etc/init.d/mysql restart

Available on Docker hub here: https://hub.docker.com/r/richardjecooke/ruby-mysql-in-memory/

Vim multiline editing like in sublimetext?

Those are some good out-of-the box solutions given above, but we can also try some plugins which provide multiple cursors like Sublime.

I think this one looks promising:

It seemed abandoned for a while, but has had some contributions in 2014.

It is quite powerful, although it took me a little while to get used to the flow (which is quite Sublime-like but still modal like Vim).

In my experience if you have a lot of other plugins installed, you may meet some conflicts!

There are some others attempts at this feature:

Please feel free to edit if you notice any of these undergoing improvement.

Is It Possible to NSLog C Structs (Like CGRect or CGPoint)?

 
NSLog(@"%@",CGRectCreateDictionaryRepresentation(rect));

How can I create my own comparator for a map?

Specify the type of the pointer to your comparison function as the 3rd type into the map, and provide the function pointer to the map constructor:
map<keyType, valueType, typeOfPointerToFunction> mapName(pointerToComparisonFunction);

Take a look at the example below for providing a comparison function to a map, with vector iterator as key and int as value.

#include "headers.h"

bool int_vector_iter_comp(const vector<int>::iterator iter1, const vector<int>::iterator iter2) {
    return *iter1 < *iter2;
}

int main() {
    // Without providing custom comparison function
    map<vector<int>::iterator, int> default_comparison;

    // Providing custom comparison function
    // Basic version
    map<vector<int>::iterator, int,
        bool (*)(const vector<int>::iterator iter1, const vector<int>::iterator iter2)>
        basic(int_vector_iter_comp);

    // use decltype
    map<vector<int>::iterator, int, decltype(int_vector_iter_comp)*> with_decltype(&int_vector_iter_comp);

    // Use type alias or using
    typedef bool my_predicate(const vector<int>::iterator iter1, const vector<int>::iterator iter2);
    map<vector<int>::iterator, int, my_predicate*> with_typedef(&int_vector_iter_comp);

    using my_predicate_pointer_type = bool (*)(const vector<int>::iterator iter1, const vector<int>::iterator iter2);
    map<vector<int>::iterator, int, my_predicate_pointer_type> with_using(&int_vector_iter_comp);


    // Testing 
    vector<int> v = {1, 2, 3};

    default_comparison.insert(pair<vector<int>::iterator, int>({v.end(), 0}));
    default_comparison.insert(pair<vector<int>::iterator, int>({v.begin(), 0}));
    default_comparison.insert(pair<vector<int>::iterator, int>({v.begin(), 1}));
    default_comparison.insert(pair<vector<int>::iterator, int>({v.begin() + 1, 1}));

    cout << "size: " << default_comparison.size() << endl;
    for (auto& p : default_comparison) {
        cout << *(p.first) << ": " << p.second << endl;
    }

    basic.insert(pair<vector<int>::iterator, int>({v.end(), 0}));
    basic.insert(pair<vector<int>::iterator, int>({v.begin(), 0}));
    basic.insert(pair<vector<int>::iterator, int>({v.begin(), 1}));
    basic.insert(pair<vector<int>::iterator, int>({v.begin() + 1, 1}));

    cout << "size: " << basic.size() << endl;
    for (auto& p : basic) {
        cout << *(p.first) << ": " << p.second << endl;
    }

    with_decltype.insert(pair<vector<int>::iterator, int>({v.end(), 0}));
    with_decltype.insert(pair<vector<int>::iterator, int>({v.begin(), 0}));
    with_decltype.insert(pair<vector<int>::iterator, int>({v.begin(), 1}));
    with_decltype.insert(pair<vector<int>::iterator, int>({v.begin() + 1, 1}));

    cout << "size: " << with_decltype.size() << endl;
    for (auto& p : with_decltype) {
        cout << *(p.first) << ": " << p.second << endl;
    }

    with_typedef.insert(pair<vector<int>::iterator, int>({v.end(), 0}));
    with_typedef.insert(pair<vector<int>::iterator, int>({v.begin(), 0}));
    with_typedef.insert(pair<vector<int>::iterator, int>({v.begin(), 1}));
    with_typedef.insert(pair<vector<int>::iterator, int>({v.begin() + 1, 1}));

    cout << "size: " << with_typedef.size() << endl;
    for (auto& p : with_typedef) {
        cout << *(p.first) << ": " << p.second << endl;
    }
}

How to replace (null) values with 0 output in PIVOT

If you have a situation where you are using dynamic columns in your pivot statement you could use the following:

DECLARE @cols               NVARCHAR(MAX)
DECLARE @colsWithNoNulls    NVARCHAR(MAX)
DECLARE @query              NVARCHAR(MAX)

SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(Name) 
            FROM Hospital
            WHERE Active = 1 AND StateId IS NOT NULL
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

SET @colsWithNoNulls = STUFF(
            (
                SELECT distinct ',ISNULL(' + QUOTENAME(Name) + ', ''No'') ' + QUOTENAME(Name)
                FROM Hospital
                WHERE Active = 1 AND StateId IS NOT NULL
                FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

EXEC ('
        SELECT Clinician, ' + @colsWithNoNulls + '
        FROM
        (
            SELECT DISTINCT p.FullName AS Clinician, h.Name, CASE WHEN phl.personhospitalloginid IS NOT NULL THEN ''Yes'' ELSE ''No'' END AS HasLogin
            FROM Person p
            INNER JOIN personlicense pl ON pl.personid = p.personid
            INNER JOIN LicenseType lt on lt.licensetypeid = pl.licensetypeid
            INNER JOIN licensetypegroup ltg ON ltg.licensetypegroupid = lt.licensetypegroupid
            INNER JOIN Hospital h ON h.StateId = pl.StateId
            LEFT JOIN PersonHospitalLogin phl ON phl.personid = p.personid AND phl.HospitalId = h.hospitalid
            WHERE ltg.Name = ''RN'' AND
                pl.licenseactivestatusid = 2 AND
                h.Active = 1 AND
                h.StateId IS NOT NULL
        ) AS Results
        PIVOT
        (
            MAX(HasLogin)
            FOR Name IN (' + @cols + ')
        ) p
')

IntelliJ IDEA 13 uses Java 1.5 despite setting to 1.7

If nothing of this helps (my case), you can set it in your pom.xml, like this:

<properties>
  <maven.compiler.source>1.7</maven.compiler.source>
  <maven.compiler.target>1.7</maven.compiler.target>
</properties>

As this cool guy mentioned here: https://stackoverflow.com/a/25888116/1643465

Rails - controller action name to string

In the specific case of a Rails action (as opposed to the general case of getting the current method name) you can use params[:action]

Alternatively you might want to look into customising the Rails log format so that the action/method name is included by the format rather than it being in your log message.

What is the function __construct used for?

I believe that function __construct () {...} is a piece of code that can be reused again and again in substitution for TheActualFunctionName () {...}. If you change the CLASS Name you do not have to change within the code because the generic __construct refers always to the actual class name...whatever it is. You code less...or?

Remove folder and its contents from git/GitHub's history

I find that the --tree-filter option used in other answers can be very slow, especially on larger repositories with lots of commits.

Here is the method I use to completely remove a directory from the git history using the --index-filter option, which runs much quicker:

# Make a fresh clone of YOUR_REPO
git clone YOUR_REPO
cd YOUR_REPO

# Create tracking branches of all branches
for remote in `git branch -r | grep -v /HEAD`; do git checkout --track $remote ; done

# Remove DIRECTORY_NAME from all commits, then remove the refs to the old commits
# (repeat these two commands for as many directories that you want to remove)
git filter-branch --index-filter 'git rm -rf --cached --ignore-unmatch DIRECTORY_NAME/' --prune-empty --tag-name-filter cat -- --all
git for-each-ref --format="%(refname)" refs/original/ | xargs -n 1 git update-ref -d

# Ensure all old refs are fully removed
rm -Rf .git/logs .git/refs/original

# Perform a garbage collection to remove commits with no refs
git gc --prune=all --aggressive

# Force push all branches to overwrite their history
# (use with caution!)
git push origin --all --force
git push origin --tags --force

You can check the size of the repository before and after the gc with:

git count-objects -vH

How to save a dictionary to a file?

Save and load dict to file:

def save_dict_to_file(dic):
    f = open('dict.txt','w')
    f.write(str(dic))
    f.close()

def load_dict_from_file():
    f = open('dict.txt','r')
    data=f.read()
    f.close()
    return eval(data)

Auto height of div

make sure the content inside your div ended with clear:both style

File Upload ASP.NET MVC 3.0

In the view:

<form action="Categories/Upload" enctype="multipart/form-data" method="post">
    <input type="file" name="Image">
    <input type="submit" value="Save">
</form>

while the following code in the controller:

public ActionResult Upload()
{
    foreach (string file in Request.Files)
    {
       var hpf = this.Request.Files[file];
       if (hpf.ContentLength == 0)
       {
            continue;
       }

       string savedFileName = Path.Combine(
                AppDomain.CurrentDomain.BaseDirectory, "PutYourUploadDirectoryHere");
                savedFileName = Path.Combine(savedFileName, Path.GetFileName(hpf.FileName));

        hpf.SaveAs(savedFileName);
    }

    ...
}

How can I convert a string to boolean in JavaScript?

A shorter way to write this, could be var isTrueSet = (myValue === "true") ? true : false; Presuming only "true" is true and other values are false.

Get a particular cell value from HTML table using JavaScript

Make a javascript function

function addSampleTextInInputBox(message) {
    //set value in input box
    document.getElementById('textInput').value = message + "";
    //or show an alert
    //window.alert(message);
}

Then simply call in your table row button click

<td class="center">
    <a class="btn btn-success" onclick="addSampleTextInInputBox('<?php echo $row->message; ?>')" title="Add" data-toggle="tooltip" title="Add">
        <span class="fa fa-plus"></span>
    </a>
</td>

MySQL error #1054 - Unknown column in 'Field List'

I had this error aswell.

I am working in mysql workbench. When giving the values they have to be inside "". That solved it for me.

Get timezone from users browser using moment(timezone).js

When using moment.js, use:

var tz = moment.tz.guess();

It will return an IANA time zone identifier, such as America/Los_Angeles for the US Pacific time zone.

It is documented here.

Internally, it first tries to get the time zone from the browser using the following call:

Intl.DateTimeFormat().resolvedOptions().timeZone

If you are targeting only modern browsers that support this function, and you don't need Moment-Timezone for anything else, then you can just call that directly.

If Moment-Timezone doesn't get a valid result from that function, or if that function doesn't exist, then it will "guess" the time zone by testing several different dates and times against the Date object to see how it behaves. The guess is usually a good enough approximation, but not guaranteed to exactly match the time zone setting of the computer.

error: ORA-65096: invalid common user or role name in oracle

 
SQL> alter session set "_ORACLE_SCRIPT"=true;  
SQL> create user sec_admin identified by "Chutinhbk123@!";

How to connect to a MS Access file (mdb) using C#?

The simplest way to connect is through an OdbcConnection using code like this

using System.Data.Odbc;

using(OdbcConnection myConnection = new OdbcConnection())
{
    myConnection.ConnectionString = myConnectionString;
    myConnection.Open();

    //execute queries, etc

}

where myConnectionString is something like this

myConnectionString = @"Driver={Microsoft Access Driver (*.mdb)};" + 
"Dbq=C:\mydatabase.mdb;Uid=Admin;Pwd=;

See ConnectionStrings

In alternative you could create a DSN and then use that DSN in your connection string

  • Open the Control Panel - Administrative Tools - ODBC Data Source Manager
  • Go to the System DSN Page and ADD a new DSN
  • Choose the Microsoft Access Driver (*.mdb) and press END
  • Set the Name of the DSN (choose MyDSN for this example)
  • Select the Database to be used
  • Try the Compact or Recover commands to see if the connection works

now your connectionString could be written in this way

myConnectionString = "DSN=myDSN;"

java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1888, result=0, data=null} to activity

I also encountered this question, I solved it through adding two conditions one is:

resultCode != null

the other is:

resultCode != RESULT_CANCELED

Creating a mock HttpServletRequest out of a url string?

Spring has MockHttpServletRequest in its spring-test module.

If you are using maven you may need to add the appropriate dependency to your pom.xml. You can find spring-test at mvnrepository.com.

How to post pictures to instagram using API

UPDATE It is now possible:

https://developers.facebook.com/docs/instagram-api/content-publishing

The Content Publishing API is a subset of Instagram Graph API endpoints that allow you to publish media objects. Publishing media objects with this API is a two step process — you first create a media object container, then publish the container on your Business Account.

Set an environment variable in git bash

A normal variable is set by simply assigning it a value; note that no whitespace is allowed around the =:

HOME=c

An environment variable is a regular variable that has been marked for export to the environment.

export HOME
HOME=c

You can combine the assignment with the export statement.

export HOME=c

C# Syntax - Split String into Array by Comma, Convert To Generic List, and Reverse Order

I realize that this question is quite old, but I had a similar problem, except my string had spaces included in it. For those that need to know how to separate a string with more than just commas:

string str = "Tom, Scott, Bob";
  IList<string> names = str.Split(new string[] {","," "},
  StringSplitOptions.RemoveEmptyEntries);

The StringSplitOptions removes the records that would only be a space char...

SQL Server 2008 - Case / If statements in SELECT Clause

The most obvious solutions are already listed. Depending on where the query is sat (i.e. in application code) you can't always use IF statements and the inline CASE statements can get painful where lots of columns become conditional. Assuming Col1 + Col3 + Col7 are the same type, and likewise Col2, Col4 + Col8 you can do this:

SELECT Col1, Col2 FROM tbl WHERE @Var LIKE 'xyz'
UNION ALL
SELECT Col3, Col4 FROM tbl WHERE @Var LIKE 'zyx'
UNION ALL
SELECT Col7, Col8 FROM tbl WHERE @Var NOT LIKE 'xyz' AND @Var NOT LIKE 'zyx'

As this is a single command there are several performance benefits with regard to plan caching. Also the Query Optimiser will quickly eliminate those statements where @Var doesn't match the appropriate value without touching the storage engine.

Replace special characters in a string with _ (underscore)

 
string = string.replace(/[&\/\\#,+()$~%.'":*?<>{}]/g,'_');

Alternatively, to change all characters except numbers and letters, try:

string = string.replace(/[^a-zA-Z0-9]/g,'_');

jQuery UI Dialog with ASP.NET button postback

FWIW, the form:first technique didn't work for me.

However, the technique in that blog article did:

http://blog.roonga.com.au/2009/07/using-jquery-ui-dialog-with-aspnet-and.html

Specifically, adding this to the dialog declaration:

  open: function(type,data) {
    $(this).parent().appendTo("form");
  }

How to change text transparency in HTML/CSS?

What about the css opacity attribute? 0 to 1 values.

But then you probably need to use a more explicit dom element than "font". For instance:

<html><body><span style=\"opacity: 0.5;\"><font color=\"black\" face=\"arial\" size=\"4\">THIS IS MY TEXT</font></span></body></html>

As an additional information I would of course suggest you use CSS declarations outside of your html elements, but as well try to use the font css style instead of the font html tag.

For cross browser css3 styles generator, have a look at http://css3please.com/

Changing Background Image with CSS3 Animations

Well I can change them in chrome. Its simple and works fine in Chrome using -webkit css properties.

PHP XML Extension: Not installed

I solved this issue with commands bellow:

$ sudo apt-get install php7.3-intl

$ sudo /etc/init.d/php7.3-fpm restart

These commands works for me in homestead with php7.3

How to compare two floating point numbers in Bash?

More conveniently

This can be done more conveniently using Bash's numeric context:

if (( $(echo "$num1 > $num2" |bc -l) )); then
  …
fi

Explanation

Piping through the basic calculator command bc returns either 1 or 0.

The option -l is equivalent to --mathlib; it loads the standard math library.

Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or false.

Please, ensure that the bc basic calculator package is installed.

This equally works for floats in scientific format, provided a capital letter E is employed, e.g. num1=3.44E6

SQL: parse the first, middle and last name from a fullname field

Based on @hajili's contribution (which is a creative use of the parsename function, intended to parse the name of an object that is period-separated), I modified it so it can handle cases where the data doesn't containt a middle name or when the name is "John and Jane Doe". It's not 100% perfect but it's compact and might do the trick depending on the business case.

SELECT NAME,
CASE WHEN parsename(replace(NAME, ' ', '.'), 4) IS NOT NULL THEN 
   parsename(replace(NAME, ' ', '.'), 4) ELSE
    CASE WHEN parsename(replace(NAME, ' ', '.'), 3) IS NOT NULL THEN 
    parsename(replace(NAME, ' ', '.'), 3) ELSE
   parsename(replace(NAME, ' ', '.'), 2) end END as FirstName
   ,
CASE WHEN parsename(replace(NAME, ' ', '.'), 3) IS NOT NULL THEN 
   parsename(replace(NAME, ' ', '.'), 2) ELSE NULL END as MiddleName,
   parsename(replace(NAME, ' ', '.'), 1) as LastName
from  {@YourTableName}

Center align with table-cell

This would be easier to do with flexbox. Using flexbox will let you not to specify the height of your content and can adjust automatically on the height it contains.

DEMO

here's the gist of the demo

.container{

  display: flex;
  height: 100%;
  justify-content: center;
  align-items: center;

}

html

<div class="container">
  <div class='content'> //you can size this anyway you want
    put anything you want here,
  </div>
</div>

enter image description here

How to copy part of an array to another array in C#?

 
int[] a = {1,2,3,4,5};

int [] b= new int[a.length]; //New Array and the size of a which is 4

Array.Copy(a,b,a.length);

Where Array is class having method Copy, which copies the element of a array to b array.

While copying from one array to another array, you have to provide same data type to another array of which you are copying.

Clear text input on click with AngularJS

 
$scope.clearSearch = function () {
    $scope.searchAll = "";
};

http://jsfiddle.net/nzPJD/

JsFiddle of how you could do it without using inline JS.

"Items collection must be empty before using ItemsSource."

I had this same error for a while in a slightly different scenario. I had 

<wpftoolkit:DataGrid
    AutoGenerateColumns="False"
    ItemsSource="{Binding Path=Accounts}" >
    <wpftoolkit:DataGridTextColumn 
        Header="Account Name" 
        Binding="{Binding Path=AccountName}" />
</wpftoolkit:DataGrid>

which I fixed to be

<wpftoolkit:DataGrid
    AutoGenerateColumns="False"
    ItemsSource="{Binding Path=Accounts}" >
    <wpftoolkit:DataGrid.Columns>
        <wpftoolkit:DataGridTextColumn 
            Header="Account Name" 
            Binding="{Binding Path=AccountName}" />
    </wpftoolkit:DataGrid.Columns>
</wpftoolkit:DataGrid>

Encrypt and Decrypt text with RSA in PHP

You can use phpseclib, a pure PHP RSA implementation:

<?php
include('Crypt/RSA.php');

$privatekey = file_get_contents('private.key');

$rsa = new Crypt_RSA();
$rsa->loadKey($privatekey);

$plaintext = new Math_BigInteger('aaaaaa');
echo $rsa->_exponentiate($plaintext)->toBytes();
?>

How to change font in ipython notebook

In addition to the suggestion by Konrad here, I'd like to suggest jupyter themes, which seems to have more options, such as line-height, font size, cell width etc.

Command line usage:

jt  [-h] [-l] [-t THEME] [-f MONOFONT] [-fs MONOSIZE] [-nf NBFONT]
[-nfs NBFONTSIZE] [-tf TCFONT] [-tfs TCFONTSIZE] [-dfs DFFONTSIZE]
[-m MARGINS] [-cursw CURSORWIDTH] [-cursc CURSORCOLOR] [-vim]
[-cellw CELLWIDTH] [-lineh LINEHEIGHT] [-altp] [-P] [-T] [-N]
[-r] [-dfonts]

Avoid dropdown menu close on click inside

The absolute best answer is to put a form tag after the class dropdown-menu

so your code is

<ul class="dropdown-menu">
  <form>
    <li>
      <div class="menu-item">bla bla bla</div>
    </li>
  </form>
</ul>

git pull while not in a git directory

For anyone like me that was trying to do this via a drush (Drupal shell) command on a remote server, you will not be able to use the solution that requires you to CD into the working directory:

Instead you need to use the solution that breaks up the pull into a fetch & merge:

drush @remote exec git --git-dir=/REPO/PATH --work-tree=/REPO/WORKDIR-PATH fetch origin
drush @remote exec git --git-dir=/REPO/PATH --work-tree=/REPO/WORKDIR-PATH merge origin/branch

Failed to serialize the response in Web API with Json

There's also this scenario that generate same error:

In case of the return being a List<dynamic> to web api method

Example:

public HttpResponseMessage Get()
{
    var item = new List<dynamic> { new TestClass { Name = "Ale", Age = 30 } };

    return Request.CreateResponse(HttpStatusCode.OK, item);
}

public class TestClass
{
    public string Name { get; set; }
    public int Age { get; set; }
}

So, for this scenario use the [KnownTypeAttribute] in the return class (all of them) like this:

[KnownTypeAttribute(typeof(TestClass))]
public class TestClass
{
    public string Name { get; set; }
    public int Age { get; set; }
}

This works for me!

In a URL, should spaces be encoded using %20 or +?

It shouldn't matter, any more than if you encoded the letter A as %41.

However, if you're dealing with a system that doesn't recognize one form, it seems like you're just going to have to give it what it expects regardless of what the "spec" says.

Partial Dependency (Databases)

If there is a Relation R(ABC)

-----------
|A | B | C |
-----------
|a | 1 | x |
|b | 1 | x |
|c | 1 | x |
|d | 2 | y |
|e | 2 | y |
|f | 3 | z |
|g | 3 | z |
 ----------
Given,
F1: A --> B 
F2: B --> C

The Primary Key and Candidate Key is: A

As the closure of A+ = {ABC} or R --- So only attribute A is sufficient to find Relation R.

DEF-1: From Some Definitions (unknown source) - A partial dependency is a dependency when prime attribute (i.e., an attribute that is a part(or proper subset) of Candidate Key) determines non-prime attribute (i.e., an attribute that is not the part (or subset) of Candidate Key).

Hence, A is a prime(P) attribute and B, C are non-prime(NP) attributes.

So, from the above DEF-1,

CONSIDERATION-1:: F1: A --> B (P determines NP) --- It must be Partial Dependency.

CONSIDERATION-2:: F2: B --> C (NP determines NP) --- Transitive Dependency.

What I understood from @philipxy answer (https://stackoverflow.com/a/25827210/6009502) is...

CONSIDERATION-1:: F1: A --> B; Should be fully functional dependency because B is completely dependent on A and If we Remove A then there is no proper subset of (for complete clarification consider L.H.S. as X NOT BY SINGLE ATTRIBUTE) that could determine B.

For Example: If I consider F1: X --> Y where X = {A} and Y = {B} then if we remove A from X; i.e., X - {A} = {}; and an empty set is not considered generally (or not at all) to define functional dependency. So, there is no proper subset of X that could hold the dependency F1: X --> Y; Hence, it is fully functional dependency.

F1: A --> B If we remove A then there is no attribute that could hold functional dependency F1. Hence, F1 is fully functional dependency not partial dependency.

If F1 were, F1: AC --> B;
and F2 were, F2: C --> B; 
then on the removal of A;
C --> B that means B is still dependent on C; 
we can say F1 is partial dependecy.

So, @philipxy answer contradicts DEF-1 and CONSIDERATION-1 that is true and crystal clear.

Hence, F1: A --> B is Fully Functional Dependency not partial dependency.

I have considered X to show left hand side of functional dependency because single attribute couldn't have a proper subset of attributes. Here, I am considering X as a set of attributes and in current scenario X is {A}

-- For the source of DEF-1, please search on google you may be able to hit similar definitions. (Consider that DEF-1 is incorrect or do not work in the above-mentioned example).

Detect if Visual C++ Redistributable for Visual Studio 2012 is installed

Just go to Control Panel > Programs and Features, and they all appear listed there.

I'm no expert and this answer is pretty simple compared to what people are answering (checking registry), so I'm not sure if it's the correct answer but it did the trick for me.

Programs and Features

What is the difference between Serialization and Marshaling?

Marshaling refers to converting the signature and parameters of a function into a single byte array. Specifically for the purpose of RPC.

Serialization more often refers to converting an entire object / object tree into a byte array Marshaling will serialize object parameters in order to add them to the message and pass it across the network. *Serialization can also be used for storage to disk.*

How to read data from a zip file without having to unzip the entire file

In such case you will need to parse zip local header entries. Each file, stored in zip file, has preceding Local File Header entry, which (normally) contains enough information for decompression, Generally, you can make simple parsing of such entries in stream, select needed file, copy header + compressed file data to other file, and call unzip on that part (if you don't want to deal with the whole Zip decompression code or library).

Using an HTTP PROXY - Python

I recommend you just use the requests module.

It is much easier than the built in http clients: http://docs.python-requests.org/en/latest/index.html

Sample usage:

r = requests.get('http://www.thepage.com', proxies={"http":"http://myproxy:3129"})
thedata = r.content

jquery get height of iframe content when loaded

Accepted answer's $('iframe').load will now produce a.indexOf is not a function error. Can be updated to:

$('iframe').on('load', function() {
  // ...
});

Few others similar to .load deprecated since jQuery 1.8: "Uncaught TypeError: a.indexOf is not a function" error when opening new foundation project

Connect with SSH through a proxy

In my case since I had a jump host or Bastion host on the way, and because the signatures on these bastion nodes had changed since they were imported into known_hosts file, I just needed to delete those entries/lines from the following file:

/Users/a.abdi-kelishami/.ssh/known_hosts

From above file, delete those lines referring to the bastion hosts.

How do I put text on ProgressBar?

Just want to point out something on @codingbadger answer. When using "ProgressBarRenderer" you should always check for "ProgressBarRenderer.IsSupported" before using the class. For me, this has been a nightmare with Visual Styles errors in Win7 that I couldn't fix. So, a better approach and workaround for the solution would be:

Rectangle clip = new Rectangle(rect.X, rect.Y, (int)Math.Round(((float)Value / Maximum) * rect.Width), rect.Height);
if (ProgressBarRenderer.IsSupported)
  ProgressBarRenderer.DrawHorizontalChunks(g, clip);
else
  g.FillRectangle(new SolidBrush(this.ForeColor), clip);

Notice that the fill will be a simple rectangle and not chunks. Chunks will be used only if ProgressBarRenderer is supported

How to loop through all elements of a form jQuery

As taken from the #jquery Freenode IRC channel:

$.each($(form).serializeArray(), function(_, field) { /* use field.name, field.value */ });

Thanks to @Cork on the channel.

Razor View throwing "The name 'model' does not exist in the current context"

I was using an MVC4 project with Visual Studio 2019 - and it turned out VS 2019 does not support MVC 4 out-of-the-box. You have to install this.

Steps:

  • Open Visual studio installer (Search for Visual Studio Installer in windows)
  • Click individual components
  • Write "mvc" in the search box
  • Check the mvc4-box
  • Click "Modify" at the bottom right

NOTE: Required for visual studio to be closed

enter image description here

Oracle DateTime in Where Clause?

As other people have commented above, using TRUNC will prevent the use of indexes (if there was an index on TIME_CREATED). To avoid that problem, the query can be structured as

SELECT EMP_NAME, DEPT
FROM EMPLOYEE
WHERE TIME_CREATED BETWEEN TO_DATE('26/JAN/2011','dd/mon/yyyy') 
            AND TO_DATE('26/JAN/2011','dd/mon/yyyy') + INTERVAL '86399' second;

86399 being 1 second less than the number of seconds in a day.

how to check if the input is a number or not in C?

Using scanf is very easy, this is an example :

if (scanf("%d", &val_a_tester) == 1) {
    ... // it's an integer
}

How to create a secure random AES key in Java?

Using KeyGenerator would be the preferred method. As Duncan indicated, I would certainly give the key size during initialization. KeyFactory is a method that should be used for pre-existing keys.

OK, so lets get to the nitty-gritty of this. In principle AES keys can have any value. There are no "weak keys" as in (3)DES. Nor are there any bits that have a specific meaning as in (3)DES parity bits. So generating a key can be as simple as generating a byte array with random values, and creating a SecretKeySpec around it.

But there are still advantages to the method you are using: the KeyGenerator is specifically created to generate keys. This means that the code may be optimized for this generation. This could have efficiency and security benefits. It might be programmed to avoid a timing side channel attacks that would expose the key, for instance. Note that it may already be a good idea to clear any byte[] that hold key information as they may be leaked into a swap file (this may be the case anyway though).

Furthermore, as said, not all algorithms are using fully random keys. So using KeyGenerator would make it easier to switch to other algorithms. More modern ciphers will only accept fully random keys though; this is seen as a major benefit over e.g. DES.

Finally, and in my case the most important reason, it that the KeyGenerator method is the only valid way of handling AES keys within a secure token (smart card, TPM, USB token or HSM). If you create the byte[] with the SecretKeySpec then the key must come from memory. That means that the key may be put in the secure token, but that the key is exposed in memory regardless. Normally, secure tokens only work with keys that are either generated in the secure token or are injected by e.g. a smart card or a key ceremony. A KeyGenerator can be supplied with a provider so that the key is directly generated within the secure token.

As indicated in Duncan's answer: always specify the key size (and any other parameters) explicitly. Do not rely on provider defaults as this will make it unclear what your application is doing, and each provider may have its own defaults.

Get top n records for each group of grouped results

Here is one way to do this, using UNION ALL (See SQL Fiddle with Demo). This works with two groups, if you have more than two groups, then you would need to specify the group number and add queries for each group:

(
  select *
  from mytable 
  where `group` = 1
  order by age desc
  LIMIT 2
)
UNION ALL
(
  select *
  from mytable 
  where `group` = 2
  order by age desc
  LIMIT 2
)

There are a variety of ways to do this, see this article to determine the best route for your situation:

http://www.xaprb.com/blog/2006/12/07/how-to-select-the-firstleastmax-row-per-group-in-sql/

Edit:

This might work for you too, it generates a row number for each record. Using an example from the link above this will return only those records with a row number of less than or equal to 2:

select person, `group`, age
from 
(
   select person, `group`, age,
      (@num:=if(@group = `group`, @num +1, if(@group := `group`, 1, 1))) row_number 
  from test t
  CROSS JOIN (select @num:=0, @group:=null) c
  order by `Group`, Age desc, person
) as x 
where x.row_number <= 2;

See Demo

ComboBox.SelectedText doesn't give me the SelectedText

Try this:

String status = "The status of my combobox is " + comboBoxTest.text;

How to set an HTTP proxy in Python 2.7?

On my network just setting http_proxy didn't work for me. The following points were relevant.

1 Setting http_proxy for your user wont be preserved when you execute sudo - to preserve it, do:

sudo -E yourcommand

I got my install working by first installing cntlm local proxy. The instructions here is succinct : http://www.leg.uct.ac.za/howtos/use-isa-proxies

Instead of student number, you'd put your domain username

2 To use the cntlm local proxy, exec:

pip install --proxy localhost:3128 pygments

Identifying and removing null characters in UNIX

I used:

recode UTF-16..UTF-8 <filename>

to get rid of zeroes in file.

How do I do logging in C# without using 3rd party libraries?

If you are looking for a real simple way to log, you can use this one liner. If the file doesn't exist, it's created.

System.IO.File.AppendAllText(@"c:\log.txt", "mymsg\n");

How to get the current taxonomy term ID (not the slug) in WordPress?

It's the term slug you want.Looks like you can get the id like this if that's what you need:

function get_term_link( $term, $taxonomy = '' ) {
    global $wp_rewrite;

    if ( !is_object($term) ) {
        if ( is_int( $term ) ) {
            $term = get_term( $term, $taxonomy );
        } else {
            $term = get_term_by( 'slug', $term, $taxonomy );
        }
    }

Received an invalid column length from the bcp client for colid 6

I just stumbled upon this and using @b_stil's snippet, I was able to figure the culprit column. And on futher investigation, I figured i needed to trim the column just like @Liji Chandran suggested but I was using IExcelDataReader and I couldn't figure out an easy way to validate and trim each of my 160 columns.

Then I stumbled upon this class, (ValidatingDataReader) class from CSVReader.

Interesting thing about this class is that it gives you the source and destination columns data length, the culprit row and even the column value that's causing the error.

All I did was just trim all (nvarchar, varchar, char and nchar) columns.

I just changed my GetValue method to this:

 object IDataRecord.GetValue(int i)
    {
        object columnValue = reader.GetValue(i);

        if (i > -1 && i < lookup.Length)
        {
            DataRow columnDef = lookup[i];
            if
            (
                (
                    (string)columnDef["DataTypeName"] == "varchar" ||
                    (string)columnDef["DataTypeName"] == "nvarchar" ||
                    (string)columnDef["DataTypeName"] == "char" ||
                    (string)columnDef["DataTypeName"] == "nchar"
                ) &&
                (
                    columnValue != null &&
                    columnValue != DBNull.Value
                )
            )
            {
                string stringValue = columnValue.ToString().Trim();

                columnValue = stringValue;


                if (stringValue.Length > (int)columnDef["ColumnSize"])
                {
                    string message =
                        "Column value \"" + stringValue.Replace("\"", "\\\"") + "\"" +
                        " with length " + stringValue.Length.ToString("###,##0") +
                        " from source column " + (this as IDataRecord).GetName(i) +
                        " in record " + currentRecord.ToString("###,##0") +
                        " does not fit in destination column " + columnDef["ColumnName"] +
                        " with length " + ((int)columnDef["ColumnSize"]).ToString("###,##0") +
                        " in table " + tableName +
                        " in database " + databaseName +
                        " on server " + serverName + ".";

                    if (ColumnException == null)
                    {
                        throw new Exception(message);
                    }
                    else
                    {
                        ColumnExceptionEventArgs args = new ColumnExceptionEventArgs();

                        args.DataTypeName = (string)columnDef["DataTypeName"];
                        args.DataType = Type.GetType((string)columnDef["DataType"]);
                        args.Value = columnValue;
                        args.SourceIndex = i;
                        args.SourceColumn = reader.GetName(i);
                        args.DestIndex = (int)columnDef["ColumnOrdinal"];
                        args.DestColumn = (string)columnDef["ColumnName"];
                        args.ColumnSize = (int)columnDef["ColumnSize"];
                        args.RecordIndex = currentRecord;
                        args.TableName = tableName;
                        args.DatabaseName = databaseName;
                        args.ServerName = serverName;
                        args.Message = message;

                        ColumnException(args);

                        columnValue = args.Value;
                    }
                }



            }
        }

        return columnValue;
    }

Hope this helps someone

How do I clear this setInterval inside a function?

 
// Initiate set interval and assign it to intervalListener
var intervalListener = self.setInterval(function () {someProcess()}, 1000);
function someProcess() {
  console.log('someProcess() has been called');
  // If some condition is true clear the interval
  if (stopIntervalIsTrue) {
    window.clearInterval(intervalListener);
  }
}

Bash script error [: !=: unary operator expected

Quotes!

if [ "$1" != -v ]; then

Otherwise, when $1 is completely empty, your test becomes:

[ != -v ]

instead of

[ "" != -v ]

...and != is not a unary operator (that is, one capable of taking only a single argument).

Android; Check if file exists without creating a new one

 
public boolean FileExists(String fname) {
        File file = getBaseContext().getFileStreamPath(fname);
        return file.exists();
}

Putting -moz-available and -webkit-fill-available in one width (css property)

CSS will skip over style declarations it doesn't understand. Mozilla-based browsers will not understand -webkit-prefixed declarations, and WebKit-based browsers will not understand -moz-prefixed declarations.

Because of this, we can simply declare width twice:

elem {
    width: 100%;
    width: -moz-available;          /* WebKit-based browsers will ignore this. */
    width: -webkit-fill-available;  /* Mozilla-based browsers will ignore this. */
    width: fill-available;
}

The width: 100% declared at the start will be used by browsers which ignore both the -moz and -webkit-prefixed declarations or do not support -moz-available or -webkit-fill-available.

String formatting in Python 3

Here are the docs about the "new" format syntax. An example would be:

"({:d} goals, ${:d})".format(self.goals, self.penalties)

If both goals and penalties are integers (i.e. their default format is ok), it could be shortened to:

"({} goals, ${})".format(self.goals, self.penalties)

And since the parameters are fields of self, there's also a way of doing it using a single argument twice (as @Burhan Khalid noted in the comments):

"({0.goals} goals, ${0.penalties})".format(self)

Explaining:

  • {} means just the next positional argument, with default format;
  • {0} means the argument with index 0, with default format;
  • {:d} is the next positional argument, with decimal integer format;
  • {0:d} is the argument with index 0, with decimal integer format.

There are many others things you can do when selecting an argument (using named arguments instead of positional ones, accessing fields, etc) and many format options as well (padding the number, using thousands separators, showing sign or not, etc). Some other examples:

"({goals} goals, ${penalties})".format(goals=2, penalties=4)
"({goals} goals, ${penalties})".format(**self.__dict__)

"first goal: {0.goal_list[0]}".format(self)
"second goal: {.goal_list[1]}".format(self)

"conversion rate: {:.2f}".format(self.goals / self.shots) # '0.20'
"conversion rate: {:.2%}".format(self.goals / self.shots) # '20.45%'
"conversion rate: {:.0%}".format(self.goals / self.shots) # '20%'

"self: {!s}".format(self) # 'Player: Bob'
"self: {!r}".format(self) # '<__main__.Player instance at 0x00BF7260>'

"games: {:>3}".format(player1.games)  # 'games: 123'
"games: {:>3}".format(player2.games)  # 'games:   4'
"games: {:0>3}".format(player2.games) # 'games: 004'

Note: As others pointed out, the new format does not supersede the former, both are available both in Python 3 and the newer versions of Python 2 as well. Some may say it's a matter of preference, but IMHO the newer is much more expressive than the older, and should be used whenever writing new code (unless it's targeting older environments, of course).

jQuery removing '-' character from string

 
$mylabel.text("-123456");
var string = $mylabel.text().replace('-', '');

if you have done it that way variable string now holds "123456"

you can also (i guess the better way) do this...

$mylabel.text("-123456");
$mylabel.text(function(i,v){
   return v.replace('-','');
});

C split a char array into different variables

I came up with this.This seems to work best for me.It converts a string of number and splits it into array of integer: 

void splitInput(int arr[], int sizeArr, char num[])
{
    for(int i = 0; i < sizeArr; i++)
        // We are subtracting 48 because the numbers in ASCII starts at 48.
        arr[i] = (int)num[i] - 48;
}

How to delete the contents of a folder?

Pretty intuitive way of doing it:

import shutil, os


def remove_folder_contents(path):
    shutil.rmtree(path)
    os.makedirs(path)


remove_folder_contents('/path/to/folder')

Skip download if files exist in wget?

The -nc, --no-clobber option isn't the best solution as newer files will not be downloaded. One should use -N instead which will download and overwrite the file only if the server has a newer version, so the correct answer is: 

wget -N http://www.example.com/images/misc/pic.png

Then running Wget with -N, with or without -r or -p, the decision as to whether or not to download a newer copy of a file depends on the local and remote timestamp and size of the file. -nc may not be specified at the same time as -N.

-N, --timestamping: Turn on time-stamping.

Java AES encryption and decryption

If for a block cipher you're not going to use a Cipher transformation that includes a padding scheme, you need to have the number of bytes in the plaintext be an integral multiple of the block size of the cipher.

So either pad out your plaintext to a multiple of 16 bytes (which is the AES block size), or specify a padding scheme when you create your Cipher objects. For example, you could use:

Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");

Unless you have a good reason not to, use a padding scheme that's already part of the JCE implementation. They've thought out a number of subtleties and corner cases you'll have to realize and deal with on your own otherwise.

Ok, your second problem is that you are using String to hold the ciphertext.

In general,

String s = new String(someBytes);
byte[] retrievedBytes = s.getBytes();

will not have someBytes and retrievedBytes being identical.

If you want/have to hold the ciphertext in a String, base64-encode the ciphertext bytes first and construct the String from the base64-encoded bytes. Then when you decrypt you'll getBytes() to get the base64-encoded bytes out of the String, then base64-decode them to get the real ciphertext, then decrypt that.

The reason for this problem is that most (all?) character encodings are not capable of mapping arbitrary bytes to valid characters. So when you create your String from the ciphertext, the String constructor (which applies a character encoding to turn the bytes into characters) essentially has to throw away some of the bytes because it can make no sense of them. Thus, when you get bytes out of the string, they are not the same bytes you put into the string.

In Java (and in modern programming in general), you cannot assume that one character = one byte, unless you know absolutely you're dealing with ASCII. This is why you need to use base64 (or something like it) if you want to build strings from arbitrary bytes.

Regular expression to return text between parenthesis

 
contents_re = re.match(r'[^\(]*\((?P<contents>[^\(]+)\)', data)
if contents_re:
    print(contents_re.groupdict()['contents'])

Python: Tuples/dictionaries as keys, select, sort

You could have a dictionary where the entries are a list of other dictionaries:

fruit_dict = dict()
fruit_dict['banana'] = [{'yellow': 24}]
fruit_dict['apple'] = [{'red': 12}, {'green': 14}]
print fruit_dict

Output:

{'banana': [{'yellow': 24}], 'apple': [{'red': 12}, {'green': 14}]}

Edit: As eumiro pointed out, you could use a dictionary of dictionaries:

fruit_dict = dict()
fruit_dict['banana'] = {'yellow': 24}
fruit_dict['apple'] = {'red': 12, 'green': 14}
print fruit_dict

Output:

{'banana': {'yellow': 24}, 'apple': {'green': 14, 'red': 12}}

Easy way to concatenate two byte arrays

For two or multiple arrays, this simple and clean utility method can be used:

/**
 * Append the given byte arrays to one big array
 *
 * @param arrays The arrays to append
 * @return The complete array containing the appended data
 */
public static final byte[] append(final byte[]... arrays) {
    final ByteArrayOutputStream out = new ByteArrayOutputStream();
    if (arrays != null) {
        for (final byte[] array : arrays) {
            if (array != null) {
                out.write(array, 0, array.length);
            }
        }
    }
    return out.toByteArray();
}

How to set column header text for specific column in Datagridview C#

If you work with visual studio designer, you will probably have defined fields for each columns in the YourForm.Designer.cs file e.g.:

private System.Windows.Forms.DataGridViewCheckBoxColumn dataGridViewCheckBoxColumn1;    
private System.Windows.Forms.DataGridViewTextBoxColumn dataGridViewTextBoxColumn2;

If you give them useful names, you can set the HeaderText easily:

usefulNameForDataGridViewTextBoxColumn.HeaderText = "Useful Header Text";

Class JavaLaunchHelper is implemented in both ... libinstrument.dylib. One of the two will be used. Which one is undefined

?? For JetBrains IntelliJ IDEA: Go to Help -> Edit Custom Properties.... Create the file if it asks you to create it. To disable the error message paste the following to the file you created:

idea_rt
idea.no.launcher=true

This will take effect on the restart of the IntelliJ.

Compare two objects in Java with possible null values

You can use java.util.Objects as following.

public static boolean compare(String str1, String str2) {
    return Objects.equals(str1, str2);
}

Twitter Bootstrap onclick event on buttons-radio

I searched so many pages: I found a beautiful solution. Check it out:

git link

<!DOCTYPE html>
<html>
<head>

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">

<!-- Optional theme -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous">

<!-- Latest compiled and minified JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
<link href="https://gitcdn.github.io/bootstrap-toggle/2.2.2/css/bootstrap-toggle.min.css" rel="stylesheet">
<script src="https://gitcdn.github.io/bootstrap-toggle/2.2.2/js/bootstrap-toggle.min.js"></script>

    <script>
        $(function() {
            $("#my_launch_today_chk").change(function() {
                var chk = $(this).prop('checked');
                if(chk == true){
                    console.log("On");
                }else{
                    console.log("OFF");
                }
            });
        });
    </script>
</head>
<body >

<input type="checkbox" id="my_launch_today_chk" checked data-on="Launch" data-off="OFF" data-toggle="toggle" data-size="small">
</body>
</html>

C#: what is the easiest way to subtract time?

try this

namespace dateandtime
{

    class DatesTime
    {

        public static DateTime Substract(DateTime now, int hours,int minutes,int seconds)
        {
            TimeSpan T1 = new TimeSpan(hours, minutes, seconds);
            return now.Subtract(T1);
        }


        static void Main(string[] args)
        {
            Console.WriteLine(Substract(DateTime.Now, 36, 0, 0).ToString());

        }
    }
}

Plotting multiple curves same graph and same scale

My solution is to use ggplot2. It takes care of these types of things automatically. The biggest thing is to arrange the data appropriately.

y1 <- c(100, 200, 300, 400, 500)
y2 <- c(1, 2, 3, 4, 5)
x <- c(1, 2, 3, 4, 5)
df <- data.frame(x=rep(x,2), y=c(y1, y2), class=c(rep("y1", 5), rep("y2", 5)))

Then use ggplot2 to plot it

library(ggplot2)
ggplot(df, aes(x=x, y=y, color=class)) + geom_point()

This is saying plot the data in df, and separate the points by class.

The plot generated isenter image description here

java.net.ConnectException: Connection refused

You have to connect your client socket to the remote ServerSocket. Instead of

Socket clientSocket = new Socket("localhost", 5000);

do

Socket clientSocket = new Socket(serverName, 5000);

The client must connect to serverName which should match the name or IP of the box on which your ServerSocket was instantiated (the name must be reachable from the client machine). BTW: It's not the name that is important, it's all about IP addresses...

Replace specific characters within strings

You do not need to create data frame from vector of strings, if you want to replace some characters in it. Regular expressions is good choice for it as it has been already mentioned by @Andrie and @Dirk Eddelbuettel.

Pay attention, if you want to replace special characters, like dots, you should employ full regular expression syntax, as shown in example below:

ctr_names <- c("Czech.Republic","New.Zealand","Great.Britain")
gsub("[.]", " ", ctr_names)

this will produce 

[1] "Czech Republic" "New Zealand"    "Great Britain"

SQL Server reports 'Invalid column name', but the column is present and the query works through management studio

Just had the exact same problem. I renamed some aliased columns in a temporary table which is further used by another part of the same code. For some reason, this was not captured by SQL Server Management Studio and it complained about invalid column names.

What I simply did is create a new query, copy paste the SQL code from the old query to this new query and run it again. This seemed to refresh the environment correctly.

When to use StringBuilder in Java

If you use String concatenation in a loop, something like this,

String s = "";
for (int i = 0; i < 100; i++) {
    s += ", " + i;
}

then you should use a StringBuilder (not StringBuffer) instead of a String, because it is much faster and consumes less memory.

If you have a single statement,

String s = "1, " + "2, " + "3, " + "4, " ...;

then you can use Strings, because the compiler will use StringBuilder automatically.

Convert a string to datetime in PowerShell

 
$invoice = "Jul-16"
[datetime]$newInvoice = "01-" + $invoice

$newInvoice.ToString("yyyy-MM-dd")

There you go, use a type accelerator, but also into a new var, if you want to use it elsewhere, use it like so: $newInvoice.ToString("yyyy-MM-dd")as $newInvoice will always be in the datetime format, unless you cast it as a string afterwards, but will lose the ability to perform datetime functions - adding days etc...

Unable to execute dex: Multiple dex files define

I removed Android dependencies from build path and it worked.

Bootstrap 3, 4 and 5 .container-fluid with grid adding unwanted padding

So here is the brief summary for Bootstrap 4:

<div class="container-fluid px-0">
  <div class="row no-gutters">
    <div class="col-12">          //any cols you need
        ...
    </div>
  </div>
</div>

It works for me.

ASP.NET MVC - Getting QueryString values

I think what you are looking for is

Request.QueryString["QueryStringName"]

and you can access it on views by adding @

now look at my example,,, I generated a Url with QueryString 

 var listURL = '@Url.RouteUrl(new { controller = "Sector", action = "List" , name = Request.QueryString["name"]})';

the listURL value is /Sector/List?name=value'

and when queryString is empty

listURL value is /Sector/List

Can a constructor in Java be private?

Basic idea behind having a private constructor is to restrict the instantiation of a class from outside by JVM, but if a class having a argument constructor, then it infers that one is intentionally instantiating.

JavaScript: Global variables after Ajax requests

The reason your code fails is because post() will start an asynchronous request to the server. What that means for you is that post() returns immediately, not after the request completes, like you are expecting.

What you need, then, is for the request to be synchronous and block the current thread until the request completes. Thus,

var it_works = false;

$.ajax({
  url: 'some_file.php',
  async: false,  # makes request synchronous
  success: function() {
    it_works = true;
  }
});

alert(it_works);

How do I bottom-align grid elements in bootstrap fluid layout

Just set the parent to display:flex; and the child to margin-top:auto. This will place the child content at the bottom of the parent element, assuming the parent element has a height greater than the child element.

There is no need to try and calculate a value for margin-top when you have a height on your parent element or another element greater than your child element of interest within your parent element.

How to force a SQL Server 2008 database to go Offline

Go offline

USE master
GO
ALTER DATABASE YourDatabaseName
SET OFFLINE WITH ROLLBACK IMMEDIATE
GO

Go online

USE master
GO
ALTER DATABASE YourDatabaseName
SET ONLINE
GO

How to show/hide JPanels in a JFrame?

Call parent.remove(panel), where parent is the container that you want the frame in and panel is the panel you want to add.

How to upload and parse a CSV file in php

You can try with this:

function doParseCSVFile($filesArray)
{
    if ((file_exists($filesArray['frmUpload']['name'])) && (is_readable($filesArray['frmUpload']['name']))) { 

        $strFilePath = $filesArray['frmUpload']['tmp_name']; 

        $strFileHandle = fopen($strFilePath,"r");
        $line_of_text = fgetcsv($strFileHandle,1024,",","'"); 
        $line_of_text = fgetcsv($strFileHandle,1024,",","'"); 

        do { 
            if ($line_of_text[0]) { 
                $strInsertSql = "INSERT INTO tbl_employee(employee_name, employee_code, employee_email, employee_designation, employee_number)VALUES('".addslashes($line_of_text[0])."', '".$line_of_text[1]."', '".addslashes($line_of_text[2])."', '".$line_of_text[3]."', '".$line_of_text[4]."')";
                ExecuteQry($strInsertSql);
            }               
        } while (($line_of_text = fgetcsv($strFileHandle,1024,",","'"))!== FALSE);

    } else {
        return FALSE;
    }
}

Annotations from javax.validation.constraints not working

I came across this problem recently in a very similar situation: Met all requirements as the top-rated answer listed but still got the wrong result.

So I looked at my dependencies and found I was missing some of them. I corrected it by adding the missing dependencies.

I was using hibernate, the required dependencies were: Dependencies Snapshot

*Snapshot taken in class "Spring & Hibernate for Beginners" @ Udemy

jQuery append() vs appendChild()

append is a jQuery method to append some content or HTML to an element.

$('#example').append('Some text or HTML');

appendChild is a pure DOM method for adding a child element.

document.getElementById('example').appendChild(newElement);

Double precision - decimal places

It is actually 53 binary places, which translates to 15 stable decimal places, meaning that if you round a start out with a number with 15 decimal places, convert it to a double, and then round the double back to 15 decimal places you'll get the same number. To uniquely represent a double you need 17 decimal places (meaning that for every number with 17 decimal places, there's a unique closest double) which is why 17 places are showing up, but not all 17-decimal numbers map to different double values (like in the examples in the other answers).

How can I send large messages with Kafka (over 15MB)?

You need to override the following properties:

Broker Configs($KAFKA_HOME/config/server.properties)

  • replica.fetch.max.bytes
  • message.max.bytes

Consumer Configs($KAFKA_HOME/config/consumer.properties)
This step didn't work for me. I add it to the consumer app and it was working fine

  • fetch.message.max.bytes

Restart the server.

look at this documentation for more info: http://kafka.apache.org/08/configuration.html

How to create a function in SQL Server

This will work for most of the website names :

SELECT ID, REVERSE(PARSENAME(REVERSE(WebsiteName), 2)) FROM dbo.YourTable .....

Event handler not working on dynamic content

You are missing the selector in the .on function:

.on(eventType, selector, function)

This selector is very important!

http://api.jquery.com/on/

If new HTML is being injected into the page, select the elements and attach event handlers after the new HTML is placed into the page. Or, use delegated events to attach an event handler

See jQuery 1.9 .live() is not a function for more details.

React hooks useState Array

Try to keep your state minimal. There is no need to store 

   const initialValue = [
    { id: 0,value: " --- Select a State ---" }];

as state. Separate the permanent from the changing

const ALL_STATE_VALS = [
    { id: 0,value: " --- Select a State ---" }
    { id: 1, value: "Alabama" },
    { id: 2, value: "Georgia" },
    { id: 3, value: "Tennessee" }
];

Then you can store just the id as your state: 

const StateSelector = () =>{
  const [selectedStateOption, setselectedStateOption] = useState(0);

  return (
    <div>
      <label>Select a State:</label>
      <select>
        {ALL_STATE_VALS.map((option, index) => (
          <option key={option.id} selected={index===selectedStateOption}>{option.value}</option>
        ))}
      </select>
    </div>);
   )
}

Java URLConnection Timeout

I have used similar code for downloading logs from servers. I debug my code and discovered that implementation of URLConnection which is returned is sun.net.www.protocol.http.HttpURLConnection.

Abstract class java.net.URLConnection have two attributes connectTimeout and readTimeout and setters are in abstract class. Believe or not implementation sun.net.www.protocol.http.HttpURLConnection have same attributes connectTimeout and readTimeout without setters and attributes from implementation class are used in getInputStream method. So there is no use of setting connectTimeout and readTimeout because they are never used in getInputStream method. In my opinion this is bug in sun.net.www.protocol.http.HttpURLConnection implementation.

My solution for this was to use HttpClient and Get request.

How to create a date object from string in javascript

Very simple:

var dt=new Date("2011/11/30");

Date should be in ISO format yyyy/MM/dd.

Android SDK location should not contain whitespace, as this cause problems with NDK tools

Simply....If you are not using NDK, there is no problem at all. On the other this is just warning not an error. With warning you can go ahead but not errors. Any it's better to adjust the whitespaces. E.g if your SDK is at C:\program file\Android studio. There is a whitespaces "program file". There are 2 simple methods: 1. Remove the whitespaces 2. Install at another location which don't have whitespaces.

installing vmware tools: location of GCC binary?

Found the answer. What I did was was first

sudo apt-get install aptitude
sudo aptitude install libglib2.0-0
sudo aptitude install gcc-4.7 make linux-headers-`uname -r` -y

and tried it but it didn't work so I continued and did

sudo apt-get install build-essential
sudo apt-get install gcc-4.7 linux-headers-`uname -r`

after doing these two steps and trying again, it worked.

equals vs Arrays.equals in Java

It's an infamous problem: .equals() for arrays is badly broken, just don't use it, ever.

That said, it's not "broken" as in "someone has done it in a really wrong way" — it's just doing what's defined and not what's usually expected. So for purists: it's perfectly fine, and that also means, don't use it, ever.

Now the expected behaviour for equals is to compare data. The default behaviour is to compare the identity, as Object does not have any data (for purists: yes it has, but it's not the point); assumption is, if you need equals in subclasses, you'll implement it. In arrays, there's no implementation for you, so you're not supposed to use it.

So the difference is, Arrays.equals(array1, array2) works as you would expect (i.e. compares content), array1.equals(array2) falls back to Object.equals implementation, which in turn compares identity, and thus better replaced by == (for purists: yes I know about null).

Problem is, even Arrays.equals(array1, array2) will bite you hard if elements of array do not implement equals properly. It's a very naive statement, I know, but there's a very important less-than-obvious case: consider a 2D array.

2D array in Java is an array of arrays, and arrays' equals is broken (or useless if you prefer), so Arrays.equals(array1, array2) will not work as you expect on 2D arrays.

Hope that helps.

Input type number "only numeric value" validation

The easiest way would be to use a library like this one and specifically you want noStrings to be true

    export class CustomValidator{   // Number only validation   
      static numeric(control: AbstractControl) {
        let val = control.value;

        const hasError = validate({val: val}, {val: {numericality: {noStrings: true}}});

        if (hasError) return null;

        return val;   
      } 
    }

TypeScript for ... of with index / key?

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/entries

for (var [key, item] of someArray.entries()) { ... }

In TS this requires targeting ES2015 since it requires the runtime to support iterators, which ES5 runtimes don't. You can of course use something like Babel to make the output work on ES5 runtimes.

How to execute UNION without sorting? (SQL)

I assume your tables are table1 and table2 respectively, and your solution is;

(select * from table1 MINUS select * from table2)
UNION ALL
(select * from table2 MINUS select * from table1)

How to calculate the 95% confidence interval for the slope in a linear regression model in R

Let's fit the model:

> library(ISwR)
> fit <- lm(metabolic.rate ~ body.weight, rmr)
> summary(fit)

Call:
lm(formula = metabolic.rate ~ body.weight, data = rmr)

Residuals:
    Min      1Q  Median      3Q     Max 
-245.74 -113.99  -32.05  104.96  484.81 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept) 811.2267    76.9755  10.539 2.29e-13 ***
body.weight   7.0595     0.9776   7.221 7.03e-09 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

Residual standard error: 157.9 on 42 degrees of freedom
Multiple R-squared: 0.5539, Adjusted R-squared: 0.5433 
F-statistic: 52.15 on 1 and 42 DF,  p-value: 7.025e-09

The 95% confidence interval for the slope is the estimated coefficient (7.0595) ± two standard errors (0.9776).

This can be computed using confint:

> confint(fit, 'body.weight', level=0.95)
               2.5 % 97.5 %
body.weight 5.086656 9.0324

How create a new deep copy (clone) of a List<T>?

 
List<Book> books_2 = new List<Book>(books_2.ToArray());

That should do exactly what you want. Demonstrated here.

Linq code to select one item

Just to make someone's life easier, the linq query with lambda expression 

(from x in Items where x.Id == 123 select x).FirstOrDefault();

does result in an SQL query with a select top (1) in it.

How can I commit a single file using SVN over a network?

strange that your command works, i thougth it would need a target directory. but it looks like it assumes current pwd as default.

cd myapp
svn ci page1.html

you can also just do svn ci in or on that folder and it will detect all changes automatically and give you a list of what will be checked in

man svn tells you the rest

SelectedValue vs SelectedItem.Value of DropDownList

They are both different. SelectedValue property gives you the actual value of the item in selection whereas SelectedItem.Text gives you the display text. For example: you drop down may have an itme like

<asp:ListItem Text="German" Value="de"></asp:ListItem>

So, in this case SelectedValue would be de and SelectedItem.Text would give 'German'

EDIT:

In that case, they aare both same ... Cause SelectedValue will give you the value stored for current selected item in your dropdown and SelectedItem.Value will be Value of the currently selected item.

So they both would give you the same result.

Condition within JOIN or WHERE

WHERE will filter after the JOIN has occurred.

Filter on the JOIN to prevent rows from being added during the JOIN process.

Is there a C++ decompiler?

I haven't seen any decompilers that generate C++ code. I've seen a few experimental ones that make a reasonable attempt at generating C code, but they tended to be dependent on matching the code-generation patterns of a particular compiler (that may have changed, it's been awhile since I last looked into this). Of course any symbolic information will be gone. Google for "decompiler".

NoClassDefFoundError on Maven dependency

when I try to run it, I get NoClassDefFoundError

Run it how? You're probably trying to run it with eclipse without having correctly imported your maven classpath. See the m2eclipse plugin for integrating maven with eclipse for that.

To verify that your maven config is correct, you could run your app with the exec plugin using:

mvn exec:java -D exec.mainClass=<your main class>

Update: First, regarding your error when running exec:java, your main class is tr.edu.hacettepe.cs.b21127113.bil138_4.App. When talking about class names, they're (almost) always dot-separated. The simple class name is just the last part: App in your case. The fully-qualified name is the full package plus the simple class name, and that's what you give to maven or java when you want to run something. What you were trying to use was a file system path to a source file. That's an entirely different beast. A class name generally translates directly to a class file that's found in the class path, as compared to a source file in the file system. In your specific case, the class file in question would probably be at target/classes/tr/edu/hacettepe/cs/b21127113/bil138_4/App.class because maven compiles to target/classes, and java traditionally creates a directory for each level of packaging.

Your original problem is simply that you haven't put the Jackson jars on your class path. When you run a java program from the command line, you have to set the class path to let it know where it can load classes from. You've added your own jar, but not the other required ones. Your comment makes me think you don't understand how to manually build a class path. In short, the class path can have two things: directories containing class files and jars containing class files. Directories containing jars won't work. For more details on building a class path, see "Setting the class path" and the java and javac tool documentation.

Your class path would need to be at least, and without the line feeds:

target/bil138_4-0.0.1-SNAPSHOT.jar:
/home/utdemir/.m2/repository/org/codehaus/jackson/jackson-core-asl/1.9.6/jackson-core-asl-1.9.6.jar:
/home/utdemir/.m2/repository/org/codehaus/jackson/jackson-mapper-asl/1.9.6/jackson-mapper-asl-1.9.6.jar

Note that the separator on Windows is a semicolon (;).

I apologize for not noticing it sooner. The problem was sitting there in your original post, but I missed it.

How do I send an HTML Form in an Email .. not just MAILTO

You are making sense, but you seem to misunderstand the concept of sending emails.

HTML is parsed on the client side, while the e-mail needs to be sent from the server. You cannot do it in pure HTML. I would suggest writing a PHP script that will deal with the email sending for you.

Basically, instead of the MAILTO, your form's action will need to point to that PHP script. In the script, retrieve the values passed by the form (in PHP, they are available through the $_POST superglobal) and use the email sending function (mail()).

Of course, this can be done in other server-side languages as well. I'm giving a PHP solution because PHP is the language I work with.

A simple example code:

form.html:

<form method="post" action="email.php">
    <input type="text" name="subject" /><br />
    <textarea name="message"></textarea>
</form>

email.php:

<?php
    mail('[email protected]', $_POST['subject'], $_POST['message']);
?>
<p>Your email has been sent.</p>

Of course, the script should contain some safety measures, such as checking whether the $_POST valies are at all available, as well as additional email headers (sender's email, for instance), perhaps a way to deal with character encoding - but that's too complex for a quick example ;).

Linq to Sql: Multiple left outer joins

Don't have access to VisualStudio (I'm on my Mac), but using the information from http://bhaidar.net/cs/archive/2007/08/01/left-outer-join-in-linq-to-sql.aspx it looks like you may be able to do something like this:

var query = from o in dc.Orders
            join v in dc.Vendors on o.VendorId equals v.Id into ov
            from x in ov.DefaultIfEmpty()
            join s in dc.Status on o.StatusId equals s.Id into os
            from y in os.DefaultIfEmpty()
            select new { o.OrderNumber, x.VendorName, y.StatusName }

Angular 2 beta.17: Property 'map' does not exist on type 'Observable<Response>'

It looks like latest RxJS requires typescript 1.8 so typescript 1.7 reports the above error.

I solved this issue by upgrading to the latest typescript version.

java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to com.testing.models.Account

When you use jackson to map from string to your concrete class, especially if you work with generic type. then this issue may happen because of different class loader. i met it one time with below scenarior:

Project B depend on Library A

in Library A:

public class DocSearchResponse<T> {
 private T data;
}

it has service to query data from external source, and use jackson to convert to concrete class

public class ServiceA<T>{
  @Autowired
  private ObjectMapper mapper;
  @Autowired
  private ClientDocSearch searchClient;

  public DocSearchResponse<T> query(Criteria criteria){
      String resultInString = searchClient.search(criteria);
      return convertJson(resultInString)
  }
}

public DocSearchResponse<T> convertJson(String result){
     return mapper.readValue(result, new TypeReference<DocSearchResponse<T>>() {});
  }
}

in Project B:

public class Account{
 private String name;
 //come with other attributes
}

and i use ServiceA from library to make query and as well convert data

public class ServiceAImpl extends ServiceA<Account> {
    
}

and make use of that

public class MakingAccountService {
    @Autowired
    private ServiceA service;
    public void execute(Criteria criteria){
      
        DocSearchResponse<Account> result = service.query(criteria);
        Account acc = result.getData(); //  java.util.LinkedHashMap cannot be cast to com.testing.models.Account
    }
}

it happen because from classloader of LibraryA, jackson can not load Account class, then just override method convertJson in Project B to let jackson do its job

public class ServiceAImpl extends ServiceA<Account> {
        @Override
        public DocSearchResponse<T> convertJson(String result){
         return mapper.readValue(result, new TypeReference<DocSearchResponse<T>>() {});
      }
    }
 }

Add custom header in HttpWebRequest

A simple method of creating the service, adding headers and reading the JSON response,

private static void WebRequest()
    {
        const string WEBSERVICE_URL = "<<Web service URL>>";
        try
        {
            var webRequest = System.Net.WebRequest.Create(WEBSERVICE_URL);
            if (webRequest != null)
            {
                webRequest.Method = "GET";
                webRequest.Timeout = 12000;
                webRequest.ContentType = "application/json";
                webRequest.Headers.Add("Authorization", "Basic dchZ2VudDM6cGFdGVzC5zc3dvmQ=");

                using (System.IO.Stream s = webRequest.GetResponse().GetResponseStream())
                {
                    using (System.IO.StreamReader sr = new System.IO.StreamReader(s))
                    {
                        var jsonResponse = sr.ReadToEnd();
                        Console.WriteLine(String.Format("Response: {0}", jsonResponse));
                    }
                }
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }
    }

Get root view from current activity

if you are in a activity, assume there is only one root view,you can get it like this.

ViewGroup viewGroup = (ViewGroup) ((ViewGroup) this
        .findViewById(android.R.id.content)).getChildAt(0);

you can then cast it to your real class

or you could using 

getWindow().getDecorView();

notice this will include the actionbar view, your view is below the actionbar view

Can I loop through a table variable in T-SQL?

look like this demo:

DECLARE @vTable TABLE (IdRow int not null primary key identity(1,1),ValueRow int);

-------Initialize---------
insert into @vTable select 345;
insert into @vTable select 795;
insert into @vTable select 565;
---------------------------

DECLARE @cnt int = 1;
DECLARE @max int = (SELECT MAX(IdRow) FROM @vTable);

WHILE @cnt <= @max
BEGIN
    DECLARE @tempValueRow int = (Select ValueRow FROM @vTable WHERE IdRow = @cnt);

    ---work demo----
    print '@tempValueRow:' + convert(varchar(10),@tempValueRow);
    print '@cnt:' + convert(varchar(10),@cnt);
    print'';
    --------------

    set @cnt = @cnt+1;
END

Version without idRow, using ROW_NUMBER

    DECLARE @vTable TABLE (ValueRow int);
-------Initialize---------
insert into @vTable select 345;
insert into @vTable select 795;
insert into @vTable select 565;
---------------------------

DECLARE @cnt int = 1;
DECLARE @max int = (select count(*) from @vTable);

WHILE @cnt <= @max
BEGIN
    DECLARE @tempValueRow int = (
        select ValueRow 
        from (select ValueRow
            , ROW_NUMBER() OVER(ORDER BY (select 1)) as RowId 
            from @vTable
        ) T1 
    where t1.RowId = @cnt
    );

    ---work demo----
    print '@tempValueRow:' + convert(varchar(10),@tempValueRow);
    print '@cnt:' + convert(varchar(10),@cnt);
    print'';
    --------------

    set @cnt = @cnt+1;
END

MySQL - UPDATE query based on SELECT Query

I had an issue with duplicate entries in one table itself. Below is the approaches were working for me. It has also been advocated by @sibaz.

Finally I solved it using the below queries:

  1. The select query is saved in a temp table

    IF OBJECT_ID(N'tempdb..#New_format_donor_temp', N'U') IS NOT NULL
    DROP TABLE #New_format_donor_temp;

select *
into #New_format_donor_temp
from DONOR_EMPLOYMENTS
where DONOR_ID IN (
  1, 2
)

-- Test New_format_donor_temp
-- SELECT *
-- FROM #New_format_donor_temp;

  2. The temp table is joined in the update query.

    UPDATE de
SET STATUS_CD=de_new.STATUS_CD, STATUS_REASON_CD=de_new.STATUS_REASON_CD, TYPE_CD=de_new.TYPE_CD
FROM DONOR_EMPLOYMENTS AS de
  INNER JOIN #New_format_donor_temp AS de_new ON de_new.EMP_NO = de.EMP_NO
WHERE
  de.DONOR_ID IN (
    3, 4
)

I not very experienced with SQL please advise any better approach you know.

Above queries are for MySql server.

Comparing Java enum members: == or equals()?

Can == be used on enum?

Yes: enums have tight instance controls that allows you to use == to compare instances. Here's the guarantee provided by the language specification (emphasis by me):

JLS 8.9 Enums

An enum type has no instances other than those defined by its enum constants.

It is a compile-time error to attempt to explicitly instantiate an enum type. The final clone method in Enum ensures that enum constants can never be cloned, and the special treatment by the serialization mechanism ensures that duplicate instances are never created as a result of deserialization. Reflective instantiation of enum types is prohibited. Together, these four things ensure that no instances of an enum type exist beyond those defined by the enum constants.

Because there is only one instance of each enum constant, it is permissible to use the == operator in place of the equals method when comparing two object references if it is known that at least one of them refers to an enum constant. (The equals method in Enum is a final method that merely invokes super.equals on its argument and returns the result, thus performing an identity comparison.)

This guarantee is strong enough that Josh Bloch recommends, that if you insist on using the singleton pattern, the best way to implement it is to use a single-element enum (see: Effective Java 2nd Edition, Item 3: Enforce the singleton property with a private constructor or an enum type; also Thread safety in Singleton)

What are the differences between == and equals?

As a reminder, it needs to be said that generally, == is NOT a viable alternative to equals. When it is, however (such as with enum), there are two important differences to consider:

== never throws NullPointerException

enum Color { BLACK, WHITE };

Color nothing = null;
if (nothing == Color.BLACK);      // runs fine
if (nothing.equals(Color.BLACK)); // throws NullPointerException

== is subject to type compatibility check at compile time

enum Color { BLACK, WHITE };
enum Chiral { LEFT, RIGHT };

if (Color.BLACK.equals(Chiral.LEFT)); // compiles fine
if (Color.BLACK == Chiral.LEFT);      // DOESN'T COMPILE!!! Incompatible types!

Should == be used when applicable?

Bloch specifically mentions that immutable classes that have proper control over their instances can guarantee to their clients that == is usable. enum is specifically mentioned to exemplify.

Item 1: Consider static factory methods instead of constructors

[...] it allows an immutable class to make the guarantee that no two equal instances exist: a.equals(b) if and only if a==b. If a class makes this guarantee, then its clients can use the == operator instead of the equals(Object) method, which may result in improved performance. Enum types provide this guarantee.

To summarize, the arguments for using == on enum are:

  • It works.
  • It's faster.
  • It's safer at run-time.
  • It's safer at compile-time.

Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)

Stoping and starting the mysql server from terminal resolved my issue. Below are the cmds to stop and start the mysql server in MacOs.

sudo /usr/local/mysql/support-files/mysql.server stop
sudo /usr/local/mysql/support-files/mysql.server start

Note: Restarting the services from Mac System preference didn't resolve the issue in my mac. So try to restart from terminal.

Change an image with onclick()

This script helps to change the image on click the text:

<script>
    $(document).ready(function(){
    $('li').click(function(){
    var imgpath = $(this).attr('dir');
    $('#image').html('<img src='+imgpath+'>');
    });
    $('.btn').click(function(){
    $('#thumbs').fadeIn(500);
    $('#image').animate({marginTop:'10px'},200);
    $(this).hide();
    $('#hide').fadeIn('slow');
    });
    $('#hide').click(function(){
    $('#thumbs').fadeOut(500,function (){
    $('#image').animate({marginTop:'50px'},200);
    });
    $(this).hide();
    $('#show').fadeIn('slow');
    });
    });
    </script>


<div class="sandiv">
<h1 style="text-align:center;">The  Human  Body  Parts :</h1>
<div id="thumbs">
<div class="sanl">
<ul>
<li dir="5.png">Human-body-organ-diag-1</li>
<li dir="4.png">Human-body-organ-diag-2</li>
<li dir="3.png">Human-body-organ-diag-3</li>
<li dir="2.png">Human-body-organ-diag-4</li>
<li dir="1.png">Human-body-organ-diag-5</li>
</ul>
</div>
</div>
<div class="man">
<div id="image">
<img src="2.png" width="348" height="375"></div>
</div>
<div id="thumbs">
<div class="sanr" >
<ul>
<li dir="5.png">Human-body-organ-diag-6</li>
<li dir="4.png">Human-body-organ-diag-7</li>
<li dir="3.png">Human-body-organ-diag-8</li>
<li dir="2.png">Human-body-organ-diag-9</li>
<li dir="1.png">Human-body-organ-diag-10</li>
</ul>
</div>
</div>
<h2><a style="color:#333;" href="http://www.sanwebcorner.com/">sanwebcorner.com</a></h2>
</div>

see the demo here

Creating a Zoom Effect on an image on hover using CSS?

_x000D_
_x000D_ 
@import url('https://fonts.googleapis.com/css?family=Muli:200,300,400,700&subset=latin-ext');_x000D_
 body{ font-family: 'Muli', sans-serif; color:white;}_x000D_
 #lists {_x000D_
   width: 350px;_x000D_
   height: 460px;_x000D_
   overflow: hidden;_x000D_
   background-color:#222222;_x000D_
   padding:0px;_x000D_
   float:left;_x000D_
    margin: 10px;_x000D_
 }_x000D_
 _x000D_
 .listimg {_x000D_
   width: 100%;_x000D_
   height: 220px;_x000D_
   overflow: hidden;_x000D_
   float: left;_x000D_
  _x000D_
 }_x000D_
  #lists .listimg img {_x000D_
   width: 350px;_x000D_
   height: 220px;_x000D_
   -moz-transition: all 0.3s;_x000D_
   -webkit-transition: all 0.3s;_x000D_
   transition: all 0.3s;_x000D_
 }_x000D_
 #lists:hover{cursor: pointer;}_x000D_
 #lists:hover > .listimg img {_x000D_
   -moz-transform: scale(1.3);_x000D_
   -webkit-transform: scale(1.3);_x000D_
   transform: scale(1.3);_x000D_
   -webkit-filter: blur(5px);_x000D_
   filter: blur(5px);_x000D_
 }_x000D_
_x000D_
#lists h1{margin:20px; display:inline-block; margin-bottom:0px; }_x000D_
#lists p{margin:20px;}_x000D_
_x000D_
.listdetail{ text-align:right; font-weight:200; padding-top:6px;padding-bottom:6px;}
_x000D_ 
<div id="lists">_x000D_
<div class="listimg">_x000D_
  <img src="https://lh3.googleusercontent.com/WeEw5I-wk2UO-y0u3Wsv8MxprCJjxTyTzvwdEc9pcdTsZVj_yK5thdtXNDKoZcUOHlegFhx7=w1920-h914-rw">_x000D_
</div>_x000D_
<div class="listtext">_x000D_
<h1>Eyes Lorem Impsum Samet</h1>_x000D_
<p>Impsum Samet Lorem</p>_x000D_
</div>_x000D_
<div class="listdetail">_x000D_
<p>Click for More Details...</p>_x000D_
</div>_x000D_
</div>_x000D_
_x000D_
<div id="lists">_x000D_
<div class="listimg">_x000D_
  <img src="https://lh4.googleusercontent.com/fqK7aQ7auobK_NyXRYCsL9SOpVj6SoYqVlgbOENw6IqQvEWzym_3988798NlkGDzu0MWnR-7nxIhj7g=w1920-h870-rw">_x000D_
</div>_x000D_
<div class="listtext">_x000D_
<h1>Two Frogs Lorem Impsum Samet</h1>_x000D_
<p>Impsum Samet Lorem</p>_x000D_
</div>_x000D_
<div class="listdetail">_x000D_
<p>More Details...</p>_x000D_
</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

"The underlying connection was closed: An unexpected error occurred on a send." With SSL Certificate

It if helps someone, ours was an issue with missing certificate. Environment is Windows Server 2016 Standard with .Net 4.6.

There is a self hosted WCF service https URI, for which Service.Open() would execute without errors. Another thread would keep accessing https://OurIp:443/OurService?wsdl to ensure that the service was available. Accessing the WSDL used to fail with:

The underlying connection was closed: An unexpected error occurred on a send.

Using ServicePointManager.SecurityProtocol with applicable settings did not work. Playing with server roles and features did not help either. Then stepped in Jaise George, the SE, resolving the issue in a couple of minutes. Jaise installed a self signed certificate in the IIS, poofing the issue. This is what he did to address the issue:

(1) Open IIS manager (inetmgr) (2) Click on the server node in the left panel, and double click "Server certificates". (3) Click on "Create Self-Signed Certificate" on the right panel and type in anything you want for the friendly name. (4) Click on “Default Web site” in the left panel, click "Bindings" on the right panel, click "Add", select "https", select the certificate you just created, and click "OK" (5) Access the https URL, it should be accessible.

Insert the same fixed value into multiple rows

 
UPDATE `table` SET table_column='test';

PowerShell Remoting giving "Access is Denied" error

Running the command prompt or Powershell ISE as an administrator fixed this for me.

How to get on scroll events?

Listen to window:scroll event for window/document level scrolling and element's scroll event for element level scrolling.

window:scroll

@HostListener('window:scroll', ['$event'])
onWindowScroll($event) {

}

or

<div (window:scroll)="onWindowScroll($event)">

scroll

@HostListener('scroll', ['$event'])
onElementScroll($event) {

}

or

<div (scroll)="onElementScroll($event)">

@HostListener('scroll', ['$event']) won't work if the host element itself is not scroll-able.

Examples

How to find the foreach index?

 
foreach(array_keys($array) as $key) {
//  do stuff
}

Move a view up only when the keyboard covers an input field

Swift 3

@IBOutlet var scrollView: UIScrollView!
@IBOutlet var edtEmail: UITextField!
@IBOutlet var bottomTextfieldConstrain: NSLayoutConstraint! // <- this guy is the constrain that connect the bottom of textField to lower object or bottom of page!

 @IBAction func edtEmailEditingDidBegin(_ sender: Any) { 
        self.bottomTextfieldConstrain.constant = 200
        let point = CGPoint(x: 0, y: 200)
        scrollView.contentOffset = point
    }

@IBAction func edtEmailEditingDidEnd(_ sender: Any) { 
    self.bottomTextfieldConstrain.constant = 50
}

Get a timestamp in C in microseconds?

But this returns some nonsense value that if I get two timestamps, the second one can be smaller or bigger than the first (second one should always be bigger).

What makes you think that? The value is probably OK. It’s the same situation as with seconds and minutes – when you measure time in minutes and seconds, the number of seconds rolls over to zero when it gets to sixty.

To convert the returned value into a “linear” number you could multiply the number of seconds and add the microseconds. But if I count correctly, one year is about 1e6*60*60*24*360 µsec and that means you’ll need more than 32 bits to store the result:

$ perl -E '$_=1e6*60*60*24*360; say int log($_)/log(2)'
44

That’s probably one of the reasons to split the original returned value into two pieces.

How to view AndroidManifest.xml from APK file?

Yes you can view XML files of an Android APK file. There is a tool for this: android-apktool

It is a tool for reverse engineering 3rd party, closed, binary Android apps

How to do this on your Windows System:

  1. Download apktool-install-windows-* file
  2. Download apktool-* file
  3. Unpack both to your Windows directory

Now copy the APK file also in that directory and run the following command in your command prompt:

apktool d HelloWorld.apk ./HelloWorld

This will create a directory "HelloWorld" in your current directory. Inside it you can find the AndroidManifest.xml file in decrypted format, and you can also find other XML files inside the "HelloWorld/res/layout" directory.

Here HelloWorld.apk is your Android APK file.

See the below screen shot for more information: alt text

Launch an app from within another (iPhone)

No it's not. Besides the documented URL handlers, there's no way to communicate with/launch another app.

How to order citations by appearance using BibTeX?

with unsrt the problem is the format. use \bibliographystyle{ieeetr} to get refences in order of citation in document.

How do I use reflection to call a generic method?

Calling a generic method with a type parameter known only at runtime can be greatly simplified by using a dynamic type instead of the reflection API.

To use this technique the type must be known from the actual object (not just an instance of the Type class). Otherwise, you have to create an object of that type or use the standard reflection API solution. You can create an object by using the Activator.CreateInstance method.

If you want to call a generic method, that in "normal" usage would have had its type inferred, then it simply comes to casting the object of unknown type to dynamic. Here's an example:

class Alpha { }
class Beta { }
class Service
{
    public void Process<T>(T item)
    {
        Console.WriteLine("item.GetType(): " + item.GetType()
                          + "\ttypeof(T): " + typeof(T));
    }
}

class Program
{
    static void Main(string[] args)
    {
        var a = new Alpha();
        var b = new Beta();

        var service = new Service();
        service.Process(a); // Same as "service.Process<Alpha>(a)"
        service.Process(b); // Same as "service.Process<Beta>(b)"

        var objects = new object[] { a, b };
        foreach (var o in objects)
        {
            service.Process(o); // Same as "service.Process<object>(o)"
        }
        foreach (var o in objects)
        {
            dynamic dynObj = o;
            service.Process(dynObj); // Or write "service.Process((dynamic)o)"
        }
    }
}

And here's the output of this program:

item.GetType(): Alpha    typeof(T): Alpha
item.GetType(): Beta     typeof(T): Beta
item.GetType(): Alpha    typeof(T): System.Object
item.GetType(): Beta     typeof(T): System.Object
item.GetType(): Alpha    typeof(T): Alpha
item.GetType(): Beta     typeof(T): Beta

Process is a generic instance method that writes the real type of the passed argument (by using the GetType() method) and the type of the generic parameter (by using typeof operator).

By casting the object argument to dynamic type we deferred providing the type parameter until runtime. When the Process method is called with the dynamic argument then the compiler doesn't care about the type of this argument. The compiler generates code that at runtime checks the real types of passed arguments (by using reflection) and choose the best method to call. Here there is only this one generic method, so it's invoked with a proper type parameter.

In this example, the output is the same as if you wrote:

foreach (var o in objects)
{
    MethodInfo method = typeof(Service).GetMethod("Process");
    MethodInfo generic = method.MakeGenericMethod(o.GetType());
    generic.Invoke(service, new object[] { o });
}

The version with a dynamic type is definitely shorter and easier to write. You also shouldn't worry about performance of calling this function multiple times. The next call with arguments of the same type should be faster thanks to the caching mechanism in DLR. Of course, you can write code that cache invoked delegates, but by using the dynamic type you get this behaviour for free.

If the generic method you want to call don't have an argument of a parametrized type (so its type parameter can't be inferred) then you can wrap the invocation of the generic method in a helper method like in the following example:

class Program
{
    static void Main(string[] args)
    {
        object obj = new Alpha();

        Helper((dynamic)obj);
    }

    public static void Helper<T>(T obj)
    {
        GenericMethod<T>();
    }

    public static void GenericMethod<T>()
    {
        Console.WriteLine("GenericMethod<" + typeof(T) + ">");
    }
}

Increased type safety

What is really great about using dynamic object as a replacement for using reflection API is that you only lose compile time checking of this particular type that you don't know until runtime. Other arguments and the name of the method are staticly analysed by the compiler as usual. If you remove or add more arguments, change their types or rename method name then you'll get a compile-time error. This won't happen if you provide the method name as a string in Type.GetMethod and arguments as the objects array in MethodInfo.Invoke.

Below is a simple example that illustrates how some errors can be caught at compile time (commented code) and other at runtime. It also shows how the DLR tries to resolve which method to call.

interface IItem { }
class FooItem : IItem { }
class BarItem : IItem { }
class Alpha { }

class Program
{
    static void Main(string[] args)
    {
        var objects = new object[] { new FooItem(), new BarItem(), new Alpha() };
        for (int i = 0; i < objects.Length; i++)
        {
            ProcessItem((dynamic)objects[i], "test" + i, i);

            //ProcesItm((dynamic)objects[i], "test" + i, i);
            //compiler error: The name 'ProcesItm' does not
            //exist in the current context

            //ProcessItem((dynamic)objects[i], "test" + i);
            //error: No overload for method 'ProcessItem' takes 2 arguments
        }
    }

    static string ProcessItem<T>(T item, string text, int number)
        where T : IItem
    {
        Console.WriteLine("Generic ProcessItem<{0}>, text {1}, number:{2}",
                          typeof(T), text, number);
        return "OK";
    }
    static void ProcessItem(BarItem item, string text, int number)
    {
        Console.WriteLine("ProcessItem with Bar, " + text + ", " + number);
    }
}

Here we again execute some method by casting the argument to the dynamic type. Only verification of first argument's type is postponed to runtime. You will get a compiler error if the name of the method you're calling doesn't exist or if other arguments are invalid (wrong number of arguments or wrong types).

When you pass the dynamic argument to a method then this call is lately bound. Method overload resolution happens at runtime and tries to choose the best overload. So if you invoke the ProcessItem method with an object of BarItem type then you'll actually call the non-generic method, because it is a better match for this type. However, you'll get a runtime error when you pass an argument of the Alpha type because there's no method that can handle this object (a generic method has the constraint where T : IItem and Alpha class doesn't implement this interface). But that's the whole point. The compiler doesn't have information that this call is valid. You as a programmer know this, and you should make sure that this code runs without errors.

Return type gotcha

When you're calling a non-void method with a parameter of dynamic type, its return type will probably be dynamic too. So if you'd change previous example to this code:

var result = ProcessItem((dynamic)testObjects[i], "test" + i, i);

then the type of the result object would be dynamic. This is because the compiler don't always know which method will be called. If you know the return type of the function call then you should implicitly convert it to the required type so the rest of the code is statically typed:

string result = ProcessItem((dynamic)testObjects[i], "test" + i, i);

You'll get a runtime error if the type doesn't match.

Actually, if you try to get the result value in the previous example then you'll get a runtime error in the second loop iteration. This is because you tried to save the return value of a void function.

How do I rewrite URLs in a proxy response in NGINX

You can use the following nginx configuration example:

upstream adminhost {
  server adminhostname:8080;
}

server {
  listen 80;

  location ~ ^/admin/(.*)$ {
    proxy_pass http://adminhost/$1$is_args$args;
    proxy_redirect off;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Host $server_name;
  }
}

How can I get the current user's username in Bash?

For Bash, KornShell (ksh), sh, etc. Many of your questions are quickly answered by either:

man [function]

to get the documentation for the system you are using or usually more conveniently:

google "man function"

This may give different results for some things where Linux and Unix have modest differences.

For this question, just enter "whoami" in your shell.

To script it:

myvar=$(whoami)

Get first row of dataframe in Python Pandas based on criteria

you can take care of the first 3 items with slicing and head:

  1. df[df.A>=4].head(1)
  2. df[(df.A>=4)&(df.B>=3)].head(1)
  3. df[(df.A>=4)&((df.B>=3) * (df.C>=2))].head(1)

The condition in case nothing comes back you can handle with a try or an if... 

try:
    output = df[df.A>=6].head(1)
    assert len(output) == 1
except: 
    output = df.sort_values('A',ascending=False).head(1)

programmatically add column & rows to WPF Datagrid

To programatically add a row:

DataGrid.Items.Add(new DataItem());

To programatically add a column: 

DataGridTextColumn textColumn = new DataGridTextColumn(); 
textColumn.Header = "First Name"; 
textColumn.Binding = new Binding("FirstName"); 
dataGrid.Columns.Add(textColumn);

Check out this post on the WPF DataGrid discussion board for more information.

How to send a "multipart/form-data" with requests in python?

Since the previous answers were written, requests have changed. Have a look at the bug thread at Github for more detail and this comment for an example.

In short, the files parameter takes a dict with the key being the name of the form field and the value being either a string or a 2, 3 or 4-length tuple, as described in the section POST a Multipart-Encoded File in the requests quickstart:

>>> url = 'http://httpbin.org/post'
>>> files = {'file': ('report.xls', open('report.xls', 'rb'), 'application/vnd.ms-excel', {'Expires': '0'})}

In the above, the tuple is composed as follows:

(filename, data, content_type, headers)

If the value is just a string, the filename will be the same as the key, as in the following:

>>> files = {'obvius_session_id': '72c2b6f406cdabd578c5fd7598557c52'}

Content-Disposition: form-data; name="obvius_session_id"; filename="obvius_session_id"
Content-Type: application/octet-stream

72c2b6f406cdabd578c5fd7598557c52

If the value is a tuple and the first entry is None the filename property will not be included:

>>> files = {'obvius_session_id': (None, '72c2b6f406cdabd578c5fd7598557c52')}

Content-Disposition: form-data; name="obvius_session_id"
Content-Type: application/octet-stream

72c2b6f406cdabd578c5fd7598557c52

SQL Server 2008 can't login with newly created user

If you haven't restarted your SQL database Server after you make login changes, then make sure you do that. Start->Programs->Microsoft SQL Server -> Configuration tools -> SQL Server configuration manager -> Restart Server.

It looks like you only added the user to the server. You need to add them to the database too. Either open the database/Security/User/Add New User or open the server/Security/Logins/Properties/User Mapping.

Regex Until But Not Including

Try this

(.*?quick.*?)z

View tabular file such as CSV from command line

I've created tablign for these (and other) purposes. Install with

pip install tablign

and

$ cat test.csv
Header1,Header2,Header3
Pizza,Artichoke dip,Bob's Special of the Day
BLT,Ham on rye with the works,

$ tablign test.csv
Header1 , Header2                   , Header3
Pizza   , Artichoke dip             , Bob's Special of the Day
BLT     , Ham on rye with the works ,

Also works if the data is separated by something else than commas. Most importantly, it preserves the delimiters so you can also use it to style your ASCII tables without sacrificing your [Markdown,CSV,LaTeX] syntax.

Order of execution of tests in TestNG

This will work. 

@Test(priority=1)
public void Test1() {

}

@Test(priority=2)
public void Test2() {

}

@Test(priority=3)
public void Test3() {

}

priority encourages execution order but does not guarantee the previous priority level has completed. test3 could start before test2 completes. If a guarantee is needed, then declare a dependency.

Unlike the solutions which declare dependencies, tests which use priority will execute even if one test fails. This problem with dependencies can be worked around with @Test(...alwaysRun = true...) according to documentation.

jQuery onclick toggle class name

It can even be made dependent to another attribute changes. like this:

$('.classA').toggleClass('classB', $('input').prop('disabled'));

In this case, classB are added each time the input is disabled

Transparent background on winforms?

Here was my solution:

In the constructors add these two lines:

this.BackColor = Color.LimeGreen;
this.TransparencyKey = Color.LimeGreen;

In your form, add this method:

protected override void OnPaintBackground(PaintEventArgs e)
{
    e.Graphics.FillRectangle(Brushes.LimeGreen, e.ClipRectangle);
}

Be warned, not only is this form fully transparent inside the frame, but you can also click through it. However, it might be cool to draw an image onto it and make the form able to be dragged everywhere to create a custom shaped form.

node.js: cannot find module 'request'

ReferenceError: Can't find variable: require.

You have installed "npm", you can run as normal the script to a "localhost" "127.0.0.1".

When you use the http.clientRequest() with "options" in a "npm" you need to install "RequireJS" inside of the module.

A module is any file or directory in the node_modules directory that can be loaded by the Node. Install "RequiereJS" for to make work the http.clientRequest(options).

Reading in from System.in - Java

In Java, console input is accomplished by reading from System.in. To obtain a character based stream that is attached to the console, wrap System.in in a BufferedReader object. BufferedReader supports a buffered input stream. Its most commonly used constructor is shown here:

BufferedReader(Reader inputReader)

Here, inputReader is the stream that is linked to the instance of BufferedReader that is being created. Reader is an abstract class. One of its concrete subclasses is InputStreamReader, which converts bytes to characters.

To obtain an InputStreamReader object that is linked to System.in, use the following constructor:

InputStreamReader(InputStream inputStream)

Because System.in refers to an object of type InputStream, it can be used for inputStream. Putting it all together, the following line of code creates a BufferedReader that is connected to the keyboard: 

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

After this statement executes, br is a character-based stream that is linked to the console through System.in.

This is taken from the book Java- The Complete Reference by Herbert Schildt

C# Convert a Base64 -> byte[]

You're looking for the FromBase64Transform class, used with the CryptoStream class.

If you have a string, you can also call Convert.FromBase64String.

Can't compile C program on a Mac after upgrade to Mojave

I had the same issue with Golang (debugging with Goland) after migration. The only (ridiculous) thing that helped is renaming the following folder:

sudo mv /usr/local/include /usr/local/old_include

Apparently it is related to old files that homebrew installed and now broken.

Git Diff with Beyond Compare

Update for BC4 64bit: This works for Git for Windows v.2.16.2 and Beyond Compare 4 - v.4.2.4 (64bit Edition)

I manually edited the .gitconfig file located in my user root "C:\Users\MyUserName" and replaced the diff/difftool and merge/mergetool tags with

[diff]
  tool = bc
[difftool "bc"]
  path = 'C:/Program Files/Beyond Compare 4/BComp.exe'
[difftool "bc"]
  cmd = \"C:/Program Files/Beyond Compare 4/BComp.exe\" \"$LOCAL\" \"$REMOTE\"
[difftool]
  prompt = false
[merge]
  tool = bc
[mergetool "bc"]
  path = 'C:/Program Files/Beyond Compare 4/BComp.exe'
[mergetool "bc"]
  cmd = \"C:/Program Files/Beyond Compare 4/BComp.exe\" \"$REMOTE\" \"$LOCAL\" \"$BASE\" \"$MERGED\"

How to enumerate an object's properties in Python?

The __dict__ property of the object is a dictionary of all its other defined properties. Note that Python classes can override getattr and make things that look like properties but are not in__dict__. There's also the builtin functions vars() and dir() which are different in subtle ways. And __slots__ can replace __dict__ in some unusual classes.

Objects are complicated in Python. __dict__ is the right place to start for reflection-style programming. dir() is the place to start if you're hacking around in an interactive shell.

ArrayList of int array in java

More simple than that.

List<Integer> arrayIntegers = new ArrayList<>(Arrays.asList(1,2,3));

arrayIntegers.get(1);

In the first line you create the object and in the constructor you pass an array parameter to List.

In the second line you have all the methods of the List class: .get (...)

Writing to a TextBox from another thread?

You need to perform the action from the thread that owns the control.

That's how I'm doing that without adding too much code noise:

control.Invoke(() => textBox1.Text += "hi");

Where Invoke overload is a simple extension from Lokad Shared Libraries:

/// <summary>
/// Invokes the specified <paramref name="action"/> on the thread that owns     
/// the <paramref name="control"/>.</summary>
/// <typeparam name="TControl">type of the control to work with</typeparam>
/// <param name="control">The control to execute action against.</param>
/// <param name="action">The action to on the thread of the control.</param>
public static void Invoke<TControl>(this TControl control, Action action) 
  where TControl : Control
{
  if (!control.InvokeRequired)
  {
    action();
  }
  else
  {
    control.Invoke(action);
  }
}

How to make my layout able to scroll down?

Just wrap all that inside a ScrollView:

<?xml version="1.0" encoding="utf-8"?>
<ScrollView
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
    <!-- Here you put the rest of your current view-->
</ScrollView>

As David Hedlund said, ScrollView can contain just one item... so if you had something like this:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
    <!-- bla bla bla-->
</LinearLayout>

You must change it to:

<?xml version="1.0" encoding="utf-8"?>
<ScrollView
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
    <LinearLayout
      android:layout_width="fill_parent"
      android:layout_height="fill_parent">
        <!-- bla bla bla-->
    </LinearLayout>
</ScrollView>

AngularJS: ng-show / ng-hide not working with `{{ }}` interpolation

Try wrapping expression with: 

$scope.$apply(function() {
   $scope.foo.bar=true;
})

Count unique values in a column in Excel

Here's an elegant array formula (which I found here http://www.excel-easy.com/examples/count-unique-values.html) that does the trick nicely:

Type

=SUM(1/COUNTIF(List,List))

and confirm with CTRL-SHIFT-ENTER

Spin or rotate an image on hover

Here is my code, this flips on hover and flips back off-hover.

CSS:

.flip-container {
  background: transparent;
  display: inline-block;
}

.flip-this {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s;
  transform-style: preserve-3d;
}

.flip-container:hover .flip-this {
  transition: 0.9s;
  transform: rotateY(180deg);
}

HTML:

<div class="flip-container">
    <div class="flip-this">
        <img width="100" alt="Godot icon" src="https://upload.wikimedia.org/wikipedia/commons/thumb/6/6a/Godot_icon.svg/512px-Godot_icon.svg.png">
    </div>
</div>

Fiddle this

Prevent Default on Form Submit jQuery

 
$(document).ready(function(){
    $("#form_id").submit(function(){
        return condition;
    });
});

Align vertically using CSS 3

I always using tutorial from this article to center things. It's great

div.container3 {
   height: 10em;
   position: relative }              /* 1 */
div.container3 p {
   margin: 0;
   position: absolute;               /* 2 */
   top: 50%;                         /* 3 */
   transform: translate(0, -50%) }   /* 4 */

The essential rules are:

  1. Make the container relatively positioned, which declares it to be a container for absolutely positioned elements.
  2. Make the element itself absolutely positioned.
  3. Place it halfway down the container with 'top: 50%'. (Note that 50%' here means 50% of the height of the container.)
  4. Use a translation to move the element up by half its own height. (The '50%' in 'translate(0, -50%)' refers to the height of the element itself.)

Pytorch tensor to numpy array

I believe you also have to use .detach(). I had to convert my Tensor to a numpy array on Colab which uses CUDA and GPU. I did it like the following:

# this is just my embedding matrix which is a Torch tensor object
embedding = learn.model.u_weight

embedding_list = list(range(0, 64382))

input = torch.cuda.LongTensor(embedding_list)
tensor_array = embedding(input)
# the output of the line below is a numpy array
tensor_array.cpu().detach().numpy()

Java, Shifting Elements in an Array

Logically it does not work and you should reverse your loop:

for (int i = position-1; i >= 0; i--) {                
    array[i+1] = array[i];
}

Alternatively you can use

System.arraycopy(array, 0, array, 1, position);

Execute external program

This is not right. Here's how you should use Runtime.exec(). You might also try its more modern cousin, ProcessBuilder:

Java Runtime.getRuntime().exec() alternatives

php refresh current page?

PHP refresh current page

With PHP code:

<?php
$secondsWait = 1;
header("Refresh:$secondsWait");
echo date('Y-m-d H:i:s');
?>

Note: Remember that header() must be called before any actual output is sent, either by normal HTML tags, blank lines in a file, or from PHP.

if you send any output, you can use javascript:

<?php
echo date('Y-m-d H:i:s');
echo '<script type="text/javascript">location.reload(true);</script>';
?>

When this method receives a true value as argument, it will cause the page to always be reloaded from the server. If it is false or not specified, the browser may reload the page from its cache.

Or you can explicitly use "meta refresh" (with pure html):

<?php
$secondsWait = 1;
echo date('Y-m-d H:i:s');
echo '<meta http-equiv="refresh" content="'.$secondsWait.'">';
?>

Greetings and good code,

How do I restart nginx only after the configuration test was successful on Ubuntu?

You can use signals to control nginx.

According to documentation, you need to send HUP signal to nginx master process.

HUP - changing configuration, keeping up with a changed time zone (only for FreeBSD and Linux), starting new worker processes with a new configuration, graceful shutdown of old worker processes

Check the documentation here: http://nginx.org/en/docs/control.html

You can send the HUP signal to nginx master process PID like this:

kill -HUP $( cat /var/run/nginx.pid )

The command above reads the nginx PID from /var/run/nginx.pid. By default nginx pid is written to /usr/local/nginx/logs/nginx.pid but that can be overridden in config. Check your nginx.config to see where it saves the PID.

Global Angular CLI version greater than local version

This works for me: it will update local version to latest

npm uninstall --save-dev angular-cli
npm install --save-dev @angular/cli@latest
npm install

to verify version

  ng --version

This IP, site or mobile application is not authorized to use this API key

For the latest version of the API the exact opposite seems to be true for me.

When calling the url https://maps.googleapis.com/maps/api/geocode/json?address=<address>&key=<key> I was getting the following error

You must use an API key to authenticate each request to Google Maps Platform APIs. For additional information, please refer to http://g.co/dev/maps-no-account

Once I switched the order to https://maps.googleapis.com/maps/api/geocode/json?key=<key>&address=<address> it worked fine.

Note that the error message received above was the message I got when going directly to the URL in the browser. When I called the API from a software program I received an HTML response with basically the following message:

We're sorry... but your computer or network may be sending automated queries. To protect our users, we can't process your request right now.

Generics/templates in python?

Here's a variant of this answer that uses metaclasses to avoid the messy syntax, and use the typing-style List[int] syntax:

class template(type):
    def __new__(metacls, f):
        cls = type.__new__(metacls, f.__name__, (), {
            '_f': f,
            '__qualname__': f.__qualname__,
            '__module__': f.__module__,
            '__doc__': f.__doc__
        })
        cls.__instances = {}
        return cls

    def __init__(cls, f):  # only needed in 3.5 and below
        pass

    def __getitem__(cls, item):
        if not isinstance(item, tuple):
            item = (item,)
        try:
            return cls.__instances[item]
        except KeyError:
            cls.__instances[item] = c = cls._f(*item)
            item_repr = '[' + ', '.join(repr(i) for i in item) + ']'
            c.__name__ = cls.__name__ + item_repr
            c.__qualname__ = cls.__qualname__ + item_repr
            c.__template__ = cls
            return c

    def __subclasscheck__(cls, subclass):
        for c in subclass.mro():
            if getattr(c, '__template__', None) == cls:
                return True
        return False

    def __instancecheck__(cls, instance):
        return cls.__subclasscheck__(type(instance))

    def __repr__(cls):
        import inspect
        return '<template {!r}>'.format('{}.{}[{}]'.format(
            cls.__module__, cls.__qualname__, str(inspect.signature(cls._f))[1:-1]
        ))

With this new metaclass, we can rewrite the example in the answer I link to as:

@template
def List(member_type):
    class List(list):
        def append(self, member):
            if not isinstance(member, member_type):
                raise TypeError('Attempted to append a "{0}" to a "{1}" which only takes a "{2}"'.format(
                    type(member).__name__,
                    type(self).__name__,
                    member_type.__name__ 
                ))

                list.append(self, member)
    return List

l = List[int]()
l.append(1)  # ok
l.append("one")  # error

This approach has some nice benefits

print(List)  # <template '__main__.List[member_type]'>
print(List[int])  # <class '__main__.List[<class 'int'>, 10]'>
assert List[int] is List[int]
assert issubclass(List[int], List)  # True

jQuery hasClass() - check for more than one class

What about this,

$.fn.extend({
     hasClasses: function( selector ) {
        var classNamesRegex = new RegExp("( " + selector.replace(/ +/g,"").replace(/,/g, " | ") + " )"),
            rclass = /[\n\t\r]/g,
            i = 0,
            l = this.length;
        for ( ; i < l; i++ ) {
            if ( this[i].nodeType === 1 && classNamesRegex.test((" " + this[i].className + " ").replace(rclass, " "))) {
                return true;
            }
        }
        return false;
    }
});

Easy to use, 

if ( $("selector").hasClasses("class1, class2, class3") ) {
  //Yes It does
}

And It seems to be faster, http://jsperf.com/hasclasstest/7

Reverse order of foreach list items

array_reverse() does not alter the source array, but returns a new array. (See array_reverse().) So you either need to store the new array first or just use function within the declaration of your for loop.

<?php 
    $input = array('a', 'b', 'c');
    foreach (array_reverse($input) as $value) {
        echo $value."\n";
    }
?>

The output will be:

c
b
a

So, to address to OP, the code becomes:

<?php
    $j=1;     
    foreach ( array_reverse($skills_nav) as $skill ) {
        $a = '<li><a href="#" data-filter=".'.$skill->slug.'">';
        $a .= $skill->name;                 
        $a .= '</a></li>';
        echo $a;
        echo "\n";
        $j++;
}

Lastly, I'm going to guess that the $j was either a counter used in an initial attempt to get a reverse walk of $skills_nav, or a way to count the $skills_nav array. If the former, it should be removed now that you have the correct solution. If the latter, it can be replaced, outside of the loop, with a $j = count($skills_nav).