Programs & Examples On #Tcpserver

A tcp server uses raw tcp sockets to communicate with its client (usually without using a higher level protocol such as HTTP or IMAP).

python socket.error: [Errno 98] Address already in use

There is obviously another process listening on the port. You might find out that process by using the following command:

$ lsof -i :8000

or change your tornado app's port. tornado's error info not Explicitly on this.

Bad File Descriptor with Linux Socket write() Bad File Descriptor C

The value you have passed as the file descriptor is not valid. It is either negative or does not represent a currently open file or socket.

So you have either closed the socket before calling write() or you have corrupted the value of 'sockfd' somewhere in your code.

It would be useful to trace all calls to close(), and the value of 'sockfd' prior to the write() calls.

Your technique of only printing error messages in debug mode seems to me complete madness, and in any case calling another function between a system call and perror() is invalid, as it may disturb the value of errno. Indeed it may have done so in this case, and the real underlying error may be different.

java.net.ConnectException: Connection refused

I changed my DNS network and it fixed the problem

how to achieve transfer file between client and server using java socket

Reading quickly through the source it seems that you're not far off. The following link should help (I did something similar but for FTP). For a file send from server to client, you start off with a file instance and an array of bytes. You then read the File into the byte array and write the byte array to the OutputStream which corresponds with the InputStream on the client's side.

http://www.rgagnon.com/javadetails/java-0542.html

Edit: Here's a working ultra-minimalistic file sender and receiver. Make sure you understand what the code is doing on both sides.

package filesendtest;

import java.io.*;
import java.net.*;

class TCPServer {

    private final static String fileToSend = "C:\\test1.pdf";

    public static void main(String args[]) {

        while (true) {
            ServerSocket welcomeSocket = null;
            Socket connectionSocket = null;
            BufferedOutputStream outToClient = null;

            try {
                welcomeSocket = new ServerSocket(3248);
                connectionSocket = welcomeSocket.accept();
                outToClient = new BufferedOutputStream(connectionSocket.getOutputStream());
            } catch (IOException ex) {
                // Do exception handling
            }

            if (outToClient != null) {
                File myFile = new File( fileToSend );
                byte[] mybytearray = new byte[(int) myFile.length()];

                FileInputStream fis = null;

                try {
                    fis = new FileInputStream(myFile);
                } catch (FileNotFoundException ex) {
                    // Do exception handling
                }
                BufferedInputStream bis = new BufferedInputStream(fis);

                try {
                    bis.read(mybytearray, 0, mybytearray.length);
                    outToClient.write(mybytearray, 0, mybytearray.length);
                    outToClient.flush();
                    outToClient.close();
                    connectionSocket.close();

                    // File sent, exit the main method
                    return;
                } catch (IOException ex) {
                    // Do exception handling
                }
            }
        }
    }
}

package filesendtest;

import java.io.*;
import java.io.ByteArrayOutputStream;
import java.net.*;

class TCPClient {

    private final static String serverIP = "127.0.0.1";
    private final static int serverPort = 3248;
    private final static String fileOutput = "C:\\testout.pdf";

    public static void main(String args[]) {
        byte[] aByte = new byte[1];
        int bytesRead;

        Socket clientSocket = null;
        InputStream is = null;

        try {
            clientSocket = new Socket( serverIP , serverPort );
            is = clientSocket.getInputStream();
        } catch (IOException ex) {
            // Do exception handling
        }

        ByteArrayOutputStream baos = new ByteArrayOutputStream();

        if (is != null) {

            FileOutputStream fos = null;
            BufferedOutputStream bos = null;
            try {
                fos = new FileOutputStream( fileOutput );
                bos = new BufferedOutputStream(fos);
                bytesRead = is.read(aByte, 0, aByte.length);

                do {
                        baos.write(aByte);
                        bytesRead = is.read(aByte);
                } while (bytesRead != -1);

                bos.write(baos.toByteArray());
                bos.flush();
                bos.close();
                clientSocket.close();
            } catch (IOException ex) {
                // Do exception handling
            }
        }
    }
}

Related

Byte array of unknown length in java

Edit: The following could be used to fingerprint small files before and after transfer (use SHA if you feel it's necessary):

public static String md5String(File file) {
    try {
        InputStream fin = new FileInputStream(file);
        java.security.MessageDigest md5er = MessageDigest.getInstance("MD5");
        byte[] buffer = new byte[1024];
        int read;
        do {
            read = fin.read(buffer);
            if (read > 0) {
                md5er.update(buffer, 0, read);
            }
        } while (read != -1);
        fin.close();
        byte[] digest = md5er.digest();
        if (digest == null) {
            return null;
        }
        String strDigest = "0x";
        for (int i = 0; i < digest.length; i++) {
            strDigest += Integer.toString((digest[i] & 0xff)
                    + 0x100, 16).substring(1).toUpperCase();
        }
        return strDigest;
    } catch (Exception e) {
        return null;
    }
}

Rails server says port already used, how to kill that process?

Some times there is a chance where rails server not closed properly. You can find process used by rails

ps aux | grep rails

Output will be like

user     12609  9.8  0.5  66456 45480 pts/0    Sl+  21:06   0:02 /home/user/.rvm/rubies/ruby-2.2.0-preview1/bin/ruby bin/rails s

Here process_id 12609 is used by your rails server.

You can kill it easily by command

kill -9 12609

socket.error: [Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions

I had to allow ..\python27\python.exe in windows firewall. I don't need to do this on WinXP or Win8.

Simple Java Client/Server Program

My try to do client socket program

server reads file and print it to console and copies it to output file

Server Program:

package SocketProgramming.copy;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class ServerRecieveFile {
    public static void main(String[] args) throws IOException {
        // TODO Auto-enerated method stub
        int filesize = 1022386;
        int bytesRead;
        int currentTot;
        ServerSocket s = new ServerSocket(0);
        int port = s.getLocalPort();
        ServerSocket serverSocket = new ServerSocket(15123);
        while (true) {
            Socket socket = serverSocket.accept();
            byte[] bytearray = new byte[filesize];
            InputStream is = socket.getInputStream();
            File copyFileName = new File("C:/Users/Username/Desktop/Output_file.txt");
            FileOutputStream fos = new FileOutputStream(copyFileName);
            BufferedOutputStream bos = new BufferedOutputStream(fos);
            bytesRead = is.read(bytearray, 0, bytearray.length);
            currentTot = bytesRead;
            do {
                bytesRead = is.read(bytearray, currentTot,
                        (bytearray.length - currentTot));
                if (bytesRead >= 0)
                    currentTot += bytesRead;
            } while (bytesRead > -1);
            bos.write(bytearray, 0, currentTot);
            bos.flush();
            bos.close();
            socket.close();
        }
    }
}

Client program:

package SocketProgramming.copy;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;

public class ClientSendFile {
    public static void main(String[] args) throws UnknownHostException,
            IOException {
        // final String FILE_NAME="C:/Users/Username/Desktop/Input_file.txt";
        final String FILE_NAME = "C:/Users/Username/Desktop/Input_file.txt";
        ServerSocket s = new ServerSocket(0);
        int port = s.getLocalPort();
        Socket socket = new Socket(InetAddress.getLocalHost(), 15123);
        System.out.println("Accepted connection : " + socket);
        File transferFile = new File(FILE_NAME);
        byte[] bytearray = new byte[(int) transferFile.length()];
        FileInputStream fin = new FileInputStream(transferFile);
        BufferedInputStream bin = new BufferedInputStream(fin);
        bin.read(bytearray, 0, bytearray.length);
        OutputStream os = socket.getOutputStream();
        System.out.println("Sending Files...");

        os.write(bytearray, 0, bytearray.length);

        BufferedReader r = new BufferedReader(new FileReader(FILE_NAME));
        String as = "", line = null;
        while ((line = r.readLine()) != null) {
            as += line + "\n";
            // as += line;

        }
        System.out.print("Input File contains following data: " + as);
        os.flush();
        fin.close();
        bin.close();
        os.close();
        socket.close();

        System.out.println("File transfer complete");
    }
}

Python socket receive - incoming packets always have a different size

The answer by Larry Hastings has some great general advice about sockets, but there are a couple of mistakes as it pertains to how the recv(bufsize) method works in the Python socket module.

So, to clarify, since this may be confusing to others looking to this for help:

  1. The bufsize param for the recv(bufsize) method is not optional. You'll get an error if you call recv() (without the param).
  2. The bufferlen in recv(bufsize) is a maximum size. The recv will happily return fewer bytes if there are fewer available.

See the documentation for details.

Now, if you're receiving data from a client and want to know when you've received all of the data, you're probably going to have to add it to your protocol -- as Larry suggests. See this recipe for strategies for determining end of message.

As that recipe points out, for some protocols, the client will simply disconnect when it's done sending data. In those cases, your while True loop should work fine. If the client does not disconnect, you'll need to figure out some way to signal your content length, delimit your messages, or implement a timeout.

I'd be happy to try to help further if you could post your exact client code and a description of your test protocol.

How to keep a Python script output window open?

You can just write

input()

at the end of your code

therefore when you run you script it will wait for you to enter something

{ENTER for example}

Regex - Does not contain certain Characters

^[^<>]+$

The caret in the character class ([^) means match anything but, so this means, beginning of string, then one or more of anything except < and >, then the end of the string.

How do I request and process JSON with python?

For anything with requests to URLs you might want to check out requests. For JSON in particular:

>>> import requests
>>> r = requests.get('https://github.com/timeline.json')
>>> r.json()
[{u'repository': {u'open_issues': 0, u'url': 'https://github.com/...

Android Studio - Device is connected but 'offline'

On windows--> Launch your terminal from the platform-tools folder inside android sdk.

Then use the following commands

adb kill server
adb start server

it should work

The given key was not present in the dictionary. Which key?

If you want to manage key misses you should use TryGetValue

https://msdn.microsoft.com/en-gb/library/bb347013(v=vs.110).aspx

string value = "";
if (openWith.TryGetValue("tif", out value))
{
    Console.WriteLine("For key = \"tif\", value = {0}.", value);
}
else
{
    Console.WriteLine("Key = \"tif\" is not found.");
}

HTTP Error 503, the service is unavailable

I changed the port from 80 to 8080, that's why this error occur. I write localhost/ in search bar then this error occur. My problem is resolved by writing localhost:8080/ in the search then local host open.

The origin server did not find a current representation for the target resource or is not willing to disclose that one exists

There is one more way to solve this problem. 1)Go to Project Explorer. Go to the target folder of your project, right-click and delete the target folder. 2)Right-click on your project, select run as Maven Build. 3)After you get Build Success on the console; right click on the project folder and select refresh. After performing the above steps, try to run your project.Your problem should be solved now.

Removing padding gutter from grid columns in Bootstrap 4

Need an edge-to-edge design? Drop the parent .container or .container-fluid.

Still if you need to remove padding from .row and immediate child columns you have to add the class .no-gutters with the code from @Brian above to your own CSS file, actually it's Not 'right out of the box', check here for official details on the final Bootstrap 4 release: https://getbootstrap.com/docs/4.0/layout/grid/#no-gutters

How to read the content of a file to a string in C?

// Assumes the file exists and will seg. fault otherwise.
const GLchar *load_shader_source(char *filename) {
  FILE *file = fopen(filename, "r");             // open 
  fseek(file, 0L, SEEK_END);                     // find the end
  size_t size = ftell(file);                     // get the size in bytes
  GLchar *shaderSource = calloc(1, size);        // allocate enough bytes
  rewind(file);                                  // go back to file beginning
  fread(shaderSource, size, sizeof(char), file); // read each char into ourblock
  fclose(file);                                  // close the stream
  return shaderSource;
}

This is a pretty crude solution because nothing is checked against null.

How to remove the first and the last character of a string

use .replace(/.*\/(\S+)\//img,"$1")

"/installers/services/".replace(/.*\/(\S+)\//img,"$1"); //--> services

"/services/".replace(/.*\/(\S+)\//img,"$1"); //--> services

Rails 4: assets not loading in production

I'm running Ubuntu Server 14.04, Ruby 2.2.1 and Rails 4.2.4 I have followed a deploy turorial from DigitalOcean and everything went well but when I go to the browser and enter the IP address of my VPS my app is loaded but without styles and javascript.

The app is running with Unicorn and Nginx. To fix this problem I entered my server using SSH with my user 'deployer' and go to my app path which is '/home/deployer/apps/blog' and run the following command:

RAILS_ENV=production bin/rake assets:precompile

Then I just restart the VPS and that's it! It works for me!

Hope it could be useful for somebody else!

Installing Numpy on 64bit Windows 7 with Python 2.7.3

You may also try this, anaconda http://continuum.io/downloads

But you need to modify your environment variable PATH, so that the anaconda folder is before the original Python folder.

Changing Placeholder Text Color with Swift

For Swift

func setPlaceholderColor(textField: UITextField, placeholderText: String) {
    textField.attributedPlaceholder = NSAttributedString(string: placeholderText, attributes: [NSForegroundColorAttributeName: UIColor.pelorBlack])
}

You can use this;

self.setPlaceholderColor(textField: self.emailTextField, placeholderText: "E-Mail/Username")

What is PEP8's E128: continuation line under-indented for visual indent?

PEP-8 recommends you indent lines to the opening parentheses if you put anything on the first line, so it should either be indenting to the opening bracket:

urlpatterns = patterns('',
                       url(r'^$', listing, name='investment-listing'))

or not putting any arguments on the starting line, then indenting to a uniform level:

urlpatterns = patterns(
    '',
    url(r'^$', listing, name='investment-listing'),
)

urlpatterns = patterns(
    '', url(r'^$', listing, name='investment-listing'))

I suggest taking a read through PEP-8 - you can skim through a lot of it, and it's pretty easy to understand, unlike some of the more technical PEPs.

Android Studio: “Execution failed for task ':app:mergeDebugResources'” if project is created on drive C:

If you are using ionic in config.xml update widget tag with "xmlns:android="http://schemas.android.com/apk/res/android"

_x000D_
_x000D_
<widget id="io.ionic.starter" version="0.0.1" xmlns="http://www.w3.org/ns/widgets" xmlns:android="http://schemas.android.com/apk/res/android" xmlns:cdv="http://cordova.apache.org/ns/1.0">_x000D_
_x000D_
_x000D_
<widget/>
_x000D_
_x000D_
_x000D_

Show ProgressDialog Android

Declare your progress dialog:

ProgressDialog progress;

When you're ready to start the progress dialog:

progress = ProgressDialog.show(this, "dialog title",
    "dialog message", true);

and to make it go away when you're done:

progress.dismiss();

Here's a little thread example for you:

// Note: declare ProgressDialog progress as a field in your class.

progress = ProgressDialog.show(this, "dialog title",
  "dialog message", true);

new Thread(new Runnable() {
  @Override
  public void run()
  {
    // do the thing that takes a long time

    runOnUiThread(new Runnable() {
      @Override
      public void run()
      {
        progress.dismiss();
      }
    });
  }
}).start();

Angles between two n-dimensional vectors in Python

Easy way to find angle between two vectors(works for n-dimensional vector),

Python code:

import numpy as np

vector1 = [1,0,0]
vector2 = [0,1,0]

unit_vector1 = vector1 / np.linalg.norm(vector1)
unit_vector2 = vector2 / np.linalg.norm(vector2)

dot_product = np.dot(unit_vector1, unit_vector2)

angle = np.arccos(dot_product) #angle in radian

How to check if two arrays are equal with JavaScript?

It handle all possible stuff and even reference itself in structure of object. You can see the example at the end of code.

var deepCompare = (function() {
    function internalDeepCompare (obj1, obj2, objects) {
        var i, objPair;

        if (obj1 === obj2) {
            return true;
        }

        i = objects.length;
        while (i--) {
            objPair = objects[i];
            if (  (objPair.obj1 === obj1 && objPair.obj2 === obj2) ||
                  (objPair.obj1 === obj2 && objPair.obj2 === obj1)  ) {                          
                return true;
            }                    
        }
        objects.push({obj1: obj1, obj2: obj2});

        if (obj1 instanceof Array) {
            if (!(obj2 instanceof Array)) {
                return false;
            }

            i = obj1.length;

            if (i !== obj2.length) {
               return false; 
            }

            while (i--) {
                if (!internalDeepCompare(obj1[i], obj2[i], objects)) {
                    return false;
                }
            }
        }
        else {
            switch (typeof obj1) {
                case "object":                
                    // deal with null
                    if (!(obj2 && obj1.constructor === obj2.constructor)) {
                        return false;
                    }

                    if (obj1 instanceof RegExp) {
                        if (!(obj2 instanceof RegExp && obj1.source === obj2.source)) {
                            return false;
                        }
                    }                 
                    else if (obj1 instanceof Date) {
                        if (!(obj2 instanceof Date && obj1.getTime() === obj2.getTime())) {
                            return false;
                        }
                    } 
                    else {    
                        for (i in obj1) {
                            if (obj1.hasOwnProperty(i)) {       
                                if (!(obj2.hasOwnProperty(i) && internalDeepCompare(obj1[i], obj2[i], objects))) {
                                    return false;
                                }
                            }
                        }         
                    }
                    break;
                case "function": 
                    if (!(typeof obj2 === "function" && obj1+"" === obj2+"")) {
                        return false;
                    }
                    break;
                default:                 //deal with NaN 
                    if (obj1 !== obj2 && obj1 === obj1 && obj2 === obj2) {
                        return false;            
                    }
            }
        }

        return true;
    }

    return function (obj1, obj2) {
        return internalDeepCompare(obj1, obj2, []);    
    };
}());

/*    
var a = [a, undefined, new Date(10), /.+/, {a:2}, function(){}, Infinity, -Infinity, NaN, 0, -0, 1, [4,5], "1", "-1", "a", null],
    b = [b, undefined, new Date(10), /.+/, {a:2}, function(){}, Infinity, -Infinity, NaN, 0, -0, 1, [4,5], "1", "-1", "a", null];
deepCompare(a, b);
*/

pandas read_csv and filter columns with usecols

import csv first and use csv.DictReader its easy to process...

Creating a generic method in C#

What about this? Change the return type from T to Nullable<T>

public static Nullable<T> GetQueryString<T>(string key) where T : struct, IConvertible
        {
            T result = default(T);

            if (String.IsNullOrEmpty(HttpContext.Current.Request.QueryString[key]) == false)
            {
                string value = HttpContext.Current.Request.QueryString[key];

                try
                {
                    result = (T)Convert.ChangeType(value, typeof(T));  
                }
                catch
                {
                    //Could not convert.  Pass back default value...
                    result = default(T);
                }
            }

            return result;
        }

REST API Best practices: Where to put parameters?

It's a very interesting question.

You can use both of them, there's not any strict rule about this subject, but using URI path variables has some advantages:

  • Cache: Most of the web cache services on the internet don't cache GET request when they contains query parameters. They do that because there are a lot of RPC systems using GET requests to change data in the server (fail!! Get must be a safe method)

But if you use path variables, all of this services can cache your GET requests.

  • Hierarchy: The path variables can represent hierarchy: /City/Street/Place

It gives the user more information about the structure of the data.

But if your data doesn't have any hierarchy relation you can still use Path variables, using comma or semi-colon:

/City/longitude,latitude

As a rule, use comma when the ordering of the parameters matter, use semi-colon when the ordering doesn't matter:

/IconGenerator/red;blue;green

Apart of those reasons, there are some cases when it's very common to use query string variables:

  • When you need the browser to automatically put HTML form variables into the URI
  • When you are dealing with algorithm. For example the google engine use query strings:

http:// www.google.com/search?q=rest

To sum up, there's not any strong reason to use one of this methods but whenever you can, use URI variables.

EditText, clear focus on touch outside

I have a ListView comprised of EditText views. The scenario says that after editing text in one or more row(s) we should click on a button called "finish". I used onFocusChanged on the EditText view inside of listView but after clicking on finish the data is not being saved. The problem was solved by adding

listView.clearFocus();

inside the onClickListener for the "finish" button and the data was saved successfully.

INSERT statement conflicted with the FOREIGN KEY constraint - SQL Server

Double check the fields in the relationship the foreign key is defined for. SQL Server Management Studio may not have had the fields you wanted selected when you defined the relationship. This has burned me in the past.

How to make the tab character 4 spaces instead of 8 spaces in nano?

In nano 2.2.6 the line in ~/.nanorc to do this seems to be

set tabsize 4

Setting tabspace gave me the error: 'Unknown flag "tabspace"'

Use .corr to get the correlation between two columns

It works like this:

Top15['Citable docs per Capita']=np.float64(Top15['Citable docs per Capita'])

Top15['Energy Supply per Capita']=np.float64(Top15['Energy Supply per Capita'])

Top15['Energy Supply per Capita'].corr(Top15['Citable docs per Capita'])

Chrome refuses to execute an AJAX script due to wrong MIME type

For the record and Google search users, If you are a .NET Core developer, you should set the content-types manually, because their default value is null or empty:

var provider = new FileExtensionContentTypeProvider();
app.UseStaticFiles(new StaticFileOptions
{
    ContentTypeProvider = provider
});

How do you grep a file and get the next 5 lines

Here is a sed solution:

sed '/19:55/{
N
N
N
N
N
s/\n/ /g
}' file.txt

iframe refuses to display

It means that the http server at cw.na1.hgncloud.com send some http headers to tell web browsers like Chrome to allow iframe loading of that page (https://cw.na1.hgncloud.com/crossmatch/) only from a page hosted on the same domain (cw.na1.hgncloud.com) :

Content-Security-Policy: frame-ancestors 'self' https://cw.na1.hgncloud.com
X-Frame-Options: ALLOW-FROM https://cw.na1.hgncloud.com

You should read that :

Bootstrap 3 navbar active li not changing background-color

in my case just removing background-image from nav-bar item solved the problem

.navbar-default .navbar-nav > .active > a:focus {
    .
    .
    .


    background-image: none;
}

Bootstrap 3 .img-responsive images are not responsive inside fieldset in FireFox

For my issue, I didn't want my images scaled to 100% when they weren't intended to be as large as the container.

For my xs container (<768px as .container), not having a fixed width drove the issue, so I put one back on to it (less the 15px col padding).

// Helps bootstrap 3.0 keep images constrained to container width when width isn't set a fixed value (below 768px), while avoiding all images at 100% width.
// NOTE: proper function relies on there being no inline styling on the element being given a defined width ( '.container'  )

function setWidth() {
    width_val = $( window ).width();
    if( width_val < 768 ) {
        $( '.container' ).width( width_val - 30 );
    } else {
        $( '.container' ).removeAttr( 'style' );
    }
}

setWidth();
$( window ).resize( setWidth );

Check whether an input string contains a number in javascript

Below code checks for same number, sequence number and reverse number sequence.

function checkNumSequnce(arrayNM2) {
    inseqCounter=1;
    continousSeq = 1;
    decsequenceConter = 1;
    var isequence = true;
    for (i=0;i<arrayNM2.length-1;i++) {
      j=i+1;
      if (arrayNM2[i] == arrayNM2[i+1]) { 
                if(inseqCounter > 1 || decsequenceConter > 1){
                    isequence =  false; break;
                }        
                 continousSeq++; 
                             
         }         
        else if (arrayNM2[j]- arrayNM2[i] == 1) {
            if(decsequenceConter > 1 || continousSeq > 1){
                isequence =  false; break;  
              }      
             inseqCounter++;               
                        
        } else if(arrayNM2[i]- arrayNM2[j] == 1){
              if(inseqCounter > 1 || continousSeq > 1){
                   isequence =  false; break;
               }
              decsequenceConter++;
        }else{
              isequence= false;
              break;
        }
  };

  console.log("isequence: "+ isequence); 

  };

Cross-Origin Read Blocking (CORB)

It seems that this warning occured when sending an empty response with a 200.

This configuration in my .htaccess display the warning on Chrome:

Header always set Access-Control-Allow-Origin "*"
Header always set Access-Control-Allow-Methods "POST,GET,HEAD,OPTIONS,PUT,DELETE"
Header always set Access-Control-Allow-Headers "Access-Control-Allow-Headers, Origin,Accept, X-Requested-With, Content-Type, Access-Control-Request-Method, Access-Control-Request-Headers, Authorization"

RewriteEngine On
RewriteCond %{REQUEST_METHOD} OPTIONS
RewriteRule .* / [R=200,L]

But changing the last line to

RewriteRule .* / [R=204,L]

resolve the issue!

"The given path's format is not supported."

Image img = Image.FromFile(System.IO.Path.GetFullPath("C:\\ File Address"));

you need getfullpath by pointed class. I had same error and fixed...

Bizarre Error in Chrome Developer Console - Failed to load resource: net::ERR_CACHE_MISS

Per the developers, this error is not an actual failure, but rather "misleading error reports". This bug is fixed in version 40, which is available on the canary and dev channels as of 25 Oct.

Patch

Google Script to see if text contains a value

Google Apps Script is javascript, you can use all the string methods...

var grade = itemResponse.getResponse();
if(grade.indexOf("9th")>-1){do something }

You can find doc on many sites, this one for example.

How to get the exact local time of client?

In JavaScript? Just instantiate a new Date object

var now = new Date();

That will create a new Date object with the client's local time.

Get current value selected in dropdown using jQuery

You can also use :checked

$("#myselect option:checked").val(); //to get value

or as said in other answers simply

$("#myselect").val(); //to get value

and

$("#myselect option:checked").text(); //to get text

How to create a secure random AES key in Java?

I would use your suggested code, but with a slight simplification:

KeyGenerator keyGen = KeyGenerator.getInstance("AES");
keyGen.init(256); // for example
SecretKey secretKey = keyGen.generateKey();

Let the provider select how it plans to obtain randomness - don't define something that may not be as good as what the provider has already selected.

This code example assumes (as Maarten points out below) that you've configured your java.security file to include your preferred provider at the top of the list. If you want to manually specify the provider, just call KeyGenerator.getInstance("AES", "providerName");.

For a truly secure key, you need to be using a hardware security module (HSM) to generate and protect the key. HSM manufacturers will typically supply a JCE provider that will do all the key generation for you, using the code above.

Why should I use core.autocrlf=true in Git?

For me.

Edit .gitattributes file.

add

*.dll binary

Then everything goes well.

How to save SELECT sql query results in an array in C# Asp.net

Instead of any Array you can load your data in DataTable like:

using System.Data;

DataTable dt = new DataTable();
using (var con = new SqlConnection("Data Source=local;Initial Catalog=Test;Integrated Security=True"))
{
    using (var command = new SqlCommand("SELECT col1,col2" +
    {
        con.Open();
        using (SqlDataReader dr = command.ExecuteReader())
        {
            dt.Load(dr);
        }
    }
}

You can also use SqlDataAdapater to fill your DataTable like

SqlDataAdapter da = new SqlDataAdapter(command);
da.Fill(dt);

Later you can iterate each row and compare like:

foreach (DataRow dr in dt.Rows)
{
    if (dr.Field<string>("col1") == "yourvalue") //your condition
    {
    }
}

What is a callback in java

A callback is some code that you pass to a given method, so that it can be called at a later time.

In Java one obvious example is java.util.Comparator. You do not usually use a Comparator directly; rather, you pass it to some code that calls the Comparator at a later time:

Example:

class CodedString implements Comparable<CodedString> {
    private int code;
    private String text;

    ...

    @Override
    public boolean equals() {
        // member-wise equality
    }

    @Override
    public int hashCode() {
        // member-wise equality 
    }

    @Override
    public boolean compareTo(CodedString cs) {
        // Compare using "code" first, then
        // "text" if both codes are equal.
    }
}

...

public void sortCodedStringsByText(List<CodedString> codedStrings) {
    Comparator<CodedString> comparatorByText = new Comparator<CodedString>() {
        @Override
        public int compare(CodedString cs1, CodedString cs2) {
            // Compare cs1 and cs2 using just the "text" field
        }
    }

    // Here we pass the comparatorByText callback to Collections.sort(...)
    // Collections.sort(...) will then call this callback whenever it
    // needs to compare two items from the list being sorted.
    // As a result, we will get the list sorted by just the "text" field.
    // If we do not pass a callback, Collections.sort will use the default
    // comparison for the class (first by "code", then by "text").
    Collections.sort(codedStrings, comparatorByText);
}

Is the Scala 2.8 collections library a case of "the longest suicide note in history"?

Scala has a lot of crazy features (particularly where implicit parameters are concerned) that look very complicated and academic, but are designed to make things easy to use. The most useful ones get syntactic sugar (like [A <% B] which means that an object of type A has an implicit conversion to an object of type B) and a well-documented explanation of what they do. But most of the time, as a client of these libraries you can ignore the implicit parameters and trust them to do the right thing.

How can I pass data from Flask to JavaScript in a template?

<script>
    const geocodeArr = JSON.parse('{{ geocode | tojson }}');
    console.log(geocodeArr);
</script>

This uses jinja2 to turn the geocode tuple into a json string, and then the javascript JSON.parse turns that into a javascript array.

What is the use of static synchronized method in java?

static methods can be synchronized. But you have one lock per class. when the java class is loaded coresponding java.lang.class class object is there. That object's lock is needed for.static synchronized methods. So when you have a static field which should be restricted to be accessed by multiple threads at once you can set those fields private and create public static synchronized setters or getters to access those fields.

How to remove the first Item from a list?

You can also use list.remove(a[0]) to pop out the first element in the list.

>>>> a=[1,2,3,4,5]
>>>> a.remove(a[0])
>>>> print a
>>>> [2,3,4,5]

Moving Average Pandas

In case you are calculating more than one moving average:

for i in range(2,10):
   df['MA{}'.format(i)] = df.rolling(window=i).mean()

Then you can do an aggregate average of all the MA

df[[f for f in list(df) if "MA" in f]].mean(axis=1)

How to vertically align an image inside a div

Use this one:

position: absolute;
top: calc(50% - 0.5em);
left: calc(50% - 0.5em);
line-height: 1em;

And you can vary font-size.

'xmlParseEntityRef: no name' warnings while loading xml into a php file

Found this here ...

Problem: An XML parser returns the error “xmlParseEntityRef: noname”

Cause: There is a stray ‘&’ (ampersand character) somewhere in the XML text eg. some text & some more text

Solution:

  • Solution 1: Remove the ampersand.
  • Solution 2: Encode the ampersand (that is replace the & character with &amp; ). Remember to Decode when reading the XML text.
  • Solution 3: Use CDATA sections (text inside a CDATA section will be ignored by the parser.) eg. <![CDATA[some text & some more text]]>

Note: ‘&’ ‘<' '>‘ will all give problems if not handled correctly.

Defining array with multiple types in TypeScript

If you're treating it as a tuple (see section 3.3.3 of the language spec), then:

var t:[number, string] = [1, "message"]

or

interface NumberStringTuple extends Array<string|number>{0:number; 1:string}
var t:NumberStringTuple = [1, "message"];

Ignore Typescript Errors "property does not exist on value of type"

A quick fix where nothing else works:

const a.b = 5 // error

const a['b'] = 5 // error if ts-lint rule no-string-literal is enabled

const B = 'b'
const a[B] = 5 // always works

Not good practice but provides a solution without needing to turn off no-string-literal

Python: printing a file to stdout

f = open('file.txt', 'r')
print f.read()
f.close()

From http://docs.python.org/tutorial/inputoutput.html

To read a file’s contents, call f.read(size), which reads some quantity of data and returns it as a string. size is an optional numeric argument. When size is omitted or negative, the entire contents of the file will be read and returned; it’s your problem if the file is twice as large as your machine’s memory. Otherwise, at most size bytes are read and returned. If the end of the file has been reached, f.read() will return an empty string ("").

How to create an Oracle sequence starting with max value from a table?

Based on Ivan Laharnar with less code and simplier:

declare
    lastSeq number;
begin
    SELECT MAX(ID) + 1 INTO lastSeq FROM <TABLE_NAME>;
    if lastSeq IS NULL then lastSeq := 1; end if;
    execute immediate 'CREATE SEQUENCE <SEQUENCE_NAME> INCREMENT BY 1 START WITH ' || lastSeq || ' MAXVALUE 999999999 MINVALUE 1 NOCACHE';
end;

Numpy how to iterate over columns of array?

Alternatively, you can use enumerate. It gives you the column number and the column values as well.

for num, column in enumerate(array.T):
    some_function(column) # column: Gives you the column value as asked in the question
    some_function(num) # num: Gives you the column number 


How do I set the request timeout for one controller action in an asp.net mvc application

I had to add "Current" using .NET 4.5:

HttpContext.Current.Server.ScriptTimeout = 300;

Use jQuery to change value of a label

val() is more like a shortcut for attr('value'). For your usage use text() or html() instead

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

The message you mention is quite clear:

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

SLF4J API could not find a binding, and decided to default to a NOP implementation. In your case slf4j-log4j12.jar was somehow not visible when the LoggerFactory class was loaded into memory, which is admittedly very strange. What does "mvn dependency:tree" tell you?

The various dependency declarations may not even be directly at cause here. I strongly suspect that a pre-1.6 version of slf4j-api.jar is being deployed without your knowledge.

Write output to a text file in PowerShell

The simplest way is to just redirect the output, like so:

Compare-Object $(Get-Content c:\user\documents\List1.txt) $(Get-Content c:\user\documents\List2.txt) > c:\user\documents\diff_output.txt

> will cause the output file to be overwritten if it already exists.
>> will append new text to the end of the output file if it already exists.

Best practice: PHP Magic Methods __set and __get

I use __get (and public properties) as much as possible, because they make code much more readable. Compare:

this code unequivocally says what i'm doing:

echo $user->name;

this code makes me feel stupid, which i don't enjoy:

function getName() { return $this->_name; }
....

echo $user->getName();

The difference between the two is particularly obvious when you access multiple properties at once.

echo "
    Dear $user->firstName $user->lastName!
    Your purchase:
        $product->name  $product->count x $product->price
"

and

echo "
    Dear " . $user->getFirstName() . " " . $user->getLastName() . "
    Your purchase: 
        " . $product->getName() . " " . $product->getCount() . "  x " . $product->getPrice() . " ";

Whether $a->b should really do something or just return a value is the responsibility of the callee. For the caller, $user->name and $user->accountBalance should look the same, although the latter may involve complicated calculations. In my data classes i use the following small method:

 function __get($p) { 
      $m = "get_$p";
      if(method_exists($this, $m)) return $this->$m();
      user_error("undefined property $p");
 }

when someone calls $obj->xxx and the class has get_xxx defined, this method will be implicitly called. So you can define a getter if you need it, while keeping your interface uniform and transparent. As an additional bonus this provides an elegant way to memorize calculations:

  function get_accountBalance() {
      $result = <...complex stuff...>
      // since we cache the result in a public property, the getter will be called only once
      $this->accountBalance = $result;
  }

  ....


   echo $user->accountBalance; // calculate the value
   ....
   echo $user->accountBalance; // use the cached value

Bottom line: php is a dynamic scripting language, use it that way, don't pretend you're doing Java or C#.

How to use <DllImport> in VB.NET?

You can also try this

Private Declare Function GetWindowText Lib "user32.dll" (ByVal hwnd As IntPtr, ByVal lpString As StringBuilder, ByVal cch As Integer) As Integer

I always use Declare Function instead of DllImport... Its more simply, its shorter and does the same

Tokenizing Error: java.util.regex.PatternSyntaxException, dangling metacharacter '*'

No, the problem is that * is a reserved character in regexes, so you need to escape it.

String [] separado = line.split("\\*");

* means "zero or more of the previous expression" (see the Pattern Javadocs), and you weren't giving it any previous expression, making your split expression illegal. This is why the error was a PatternSyntaxException.

Difference between HashSet and HashMap?

The main difference between them you can find as follows:

HashSet

  • It does not allow duplicate keys.
  • Even it is not synchronized, so this will have better performance.
  • It allows a null key.
  • HashSet can be used when you want to maintain a unique list.
  • HashSet implements Set interface and it is backed by the hash table(actually HashMap instance).
  • HashSet stores objects.
  • HashSet doesn’t allow duplicate elements but null values are allowed.
  • This interface doesn’t guarantee that order will remain constant over time.

HashMap

  • It allows duplicate keys. It is not synchronized, so this will have better performance.
  • HashMap does not maintain insertion order.
  • The order is defined by the Hash function.
  • It is not Thread Safe
  • It allows null for both key and value.
  • It allows one null key and as many null values as you like.
  • HashMap is a Hash table-based implementation of the Map interface.
  • HashMap store object as key and value pair.
  • HashMap does not allow duplicate keys but null keys and values are allowed.
  • Ordering of the element is not guaranteed overtime.

SQL Error: ORA-00942 table or view does not exist

Because this post is the top one found on stackoverflow when searching for "ORA-00942: table or view does not exist insert", I want to mention another possible cause of this error (at least in Oracle 12c): a table uses a sequence to set a default value and the user executing the insert query does not have select privilege on the sequence. This was my problem and it took me an unnecessarily long time to figure it out.

To reproduce the problem, execute the following SQL as user1:

create sequence seq_customer_id;

create table customer (
c_id number(10) default seq_customer_id.nextval primary key,
name varchar(100) not null,
surname varchar(100) not null
);

grant select, insert, update, delete on customer to user2;

Then, execute this insert statement as user2:

insert into user1.customer (name,surname) values ('michael','jackson');

The result will be "ORA-00942: table or view does not exist" even though user2 does have insert and select privileges on user1.customer table and is correctly prefixing the table with the schema owner name. To avoid the problem, you must grant select privilege on the sequence:

grant select on seq_customer_id to user2;

Preferred Java way to ping an HTTP URL for availability

here the writer suggests this:

public boolean isOnline() {
    Runtime runtime = Runtime.getRuntime();
    try {
        Process ipProcess = runtime.exec("/system/bin/ping -c 1 8.8.8.8");
        int     exitValue = ipProcess.waitFor();
        return (exitValue == 0);
    } catch (IOException | InterruptedException e) { e.printStackTrace(); }
    return false;
}

Possible Questions

  • Is this really fast enough?Yes, very fast!
  • Couldn’t I just ping my own page, which I want to request anyways? Sure! You could even check both, if you want to differentiate between “internet connection available” and your own servers beeing reachable What if the DNS is down? Google DNS (e.g. 8.8.8.8) is the largest public DNS service in the world. As of 2013 it serves 130 billion requests a day. Let ‘s just say, your app not responding would probably not be the talk of the day.

read the link. its seems very good

EDIT: in my exp of using it, it's not as fast as this method:

public boolean isOnline() {
    NetworkInfo netInfo = connectivityManager.getActiveNetworkInfo();
    return netInfo != null && netInfo.isConnectedOrConnecting();
}

they are a bit different but in the functionality for just checking the connection to internet the first method may become slow due to the connection variables.

Convert Enum to String

In my tests, Enum.GetName was faster and by decent margin. Internally ToString calls Enum.GetName. From source for .NET 4.0, the essentials:

public override String ToString()
{
     return Enum.InternalFormat((RuntimeType)GetType(), GetValue());
}

private static String InternalFormat(RuntimeType eT, Object value)
{
    if (!eT.IsDefined(typeof(System.FlagsAttribute), false))
    {
        String retval = GetName(eT, value); //<== the one
        if (retval == null)
            return value.ToString();
        else
            return retval;
    }
    else
    {
        return InternalFlagsFormat(eT, value);
    }
}

I cant say that is the reason for sure, but tests state one is faster than the other. Both the calls involve boxing (in fact they are reflection calls, you're essentially retrieving field names) and can be slow for your liking.

Test setup: enum with 8 values, no. of iterations = 1000000

Result: Enum.GetName => 700 ms, ToString => 2000 ms

If speed isn't noticeable, I wouldn't care and use ToString since it offers a much cleaner call. Contrast

Enum.GetName(typeof(Bla), value)

with

value.ToString()

Add all files to a commit except a single file?

To keep the change in file but not to commit I did this

git add .

git reset -- main/dontcheckmein.txt

git commit -m "commit message"

to verify the file is excluded do

git status

What is "Linting"?

Linting is a process by a linter program that analyzes source code in a particular programming language and flag potential problems like syntax errors, deviations from a prescribed coding style or using constructs known to be unsafe.

For example, a JavaScript linter would flag the first use of parseInt below as unsafe:

// without a radix argument - Unsafe
var count = parseInt(countString);

// with a radix paremeter specified - Safe
var count = parseInt(countString, 10);

Twitter Bootstrap 3: how to use media queries?

Bootstrap 3

Here are the selectors used in BS3, if you want to stay consistent:

@media(max-width:767px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}

Note: FYI, this may be useful for debugging:

<span class="visible-xs">SIZE XS</span>
<span class="visible-sm">SIZE SM</span>
<span class="visible-md">SIZE MD</span>
<span class="visible-lg">SIZE LG</span>

Bootstrap 4

Here are the selectors used in BS4. There is no "lowest" setting in BS4 because "extra small" is the default. I.e. you would first code the XS size and then have these media overrides afterwards.

@media(min-width:576px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}

Update 2019-02-11: BS3 info is still accurate as of version 3.4.0, updated BS4 for new grid, accurate as of 4.3.0.

How can I tell which button was clicked in a PHP form submit?

In HTML:

<input type="submit" id="btnSubmit" name="btnSubmit" value="Save Changes" />
<input type="submit" id="btnDelete" name="btnDelete" value="Delete" />

In PHP:

if (isset($_POST["btnSubmit"])){
  // "Save Changes" clicked
} else if (isset($_POST["btnDelete"])){
  // "Delete" clicked
}

How to remove carriage return and newline from a variable in shell script

Because the file you source ends lines with carriage returns, the contents of $testVar are likely to look like this:

$ printf '%q\n' "$testVar"
$'value123\r'

(The first line's $ is the shell prompt; the second line's $ is from the %q formatting string, indicating $'' quoting.)

To get rid of the carriage return, you can use shell parameter expansion and ANSI-C quoting (requires Bash):

testVar=${testVar//$'\r'}

Which should result in

$ printf '%q\n' "$testVar"
value123

How to keep an iPhone app running on background fully operational

May be the link will Help bcz u might have to implement the code in Appdelegate in app run in background method .. Also consult the developer.apple.com site for application class Here is link for runing app in background

How to Customize the time format for Python logging?

if using logging.config.fileConfig with a configuration file use something like:

[formatter_simpleFormatter]
format=%(asctime)s - %(name)s - %(levelname)s - %(message)s
datefmt=%Y-%m-%d %H:%M:%S

MongoDB logging all queries

Because its google first answer ...
For version 3

$ mongo
MongoDB shell version: 3.0.2
connecting to: test
> use myDb
switched to db
> db.setLogLevel(1)

http://docs.mongodb.org/manual/reference/method/db.setLogLevel/

How can I emulate a get request exactly like a web browser?

Are you sure the curl module honors ini_set('user_agent',...)? There is an option CURLOPT_USERAGENT described at http://docs.php.net/function.curl-setopt.
Could there also be a cookie tested by the server? That you can handle by using CURLOPT_COOKIE, CURLOPT_COOKIEFILE and/or CURLOPT_COOKIEJAR.

edit: Since the request uses https there might also be error in verifying the certificate, see CURLOPT_SSL_VERIFYPEER.

$url="https://new.aol.com/productsweb/subflows/ScreenNameFlow/AjaxSNAction.do?s=username&f=firstname&l=lastname";
$agent= 'Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.0.3705; .NET CLR 1.1.4322)';

$ch = curl_init();
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_VERBOSE, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_USERAGENT, $agent);
curl_setopt($ch, CURLOPT_URL,$url);
$result=curl_exec($ch);
var_dump($result);

How to access a preexisting collection with Mongoose?

You can do something like this, than you you'll access the native mongodb functions inside mongoose:

var mongoose = require("mongoose");
mongoose.connect('mongodb://localhost/local');

var connection = mongoose.connection;

connection.on('error', console.error.bind(console, 'connection error:'));
connection.once('open', function () {

    connection.db.collection("YourCollectionName", function(err, collection){
        collection.find({}).toArray(function(err, data){
            console.log(data); // it will print your collection data
        })
    });

});

How to make a view with rounded corners?

Create a xml file called round.xml in the drawable folder and paste this content:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
  <solid android:color="#FFFFFF" />
  <stroke android:width=".05dp" android:color="#d2d2d2" />
  <corners android:topLeftRadius="5dp" android:topRightRadius="5dp" android:bottomRightRadius="5dp" android:bottomLeftRadius="5dp"/>
</shape>

then use the round.xml as background to any item. Then it will give you rounded corners.

Add line break to ::after or ::before pseudo-element content

Found this question here that seems to ask the same thing: Newline character sequence in CSS 'content' property?

Looks like you can use \A or \00000a to achieve a newline

Can multiple different HTML elements have the same ID if they're different elements?

Nope, IDs have to be unique. You can use classes for that purpose

<div class="a" /><div class="a b" /><span class="a" />

div.a {font: ...;}
/* or just: */
.a {prop: value;}

UnicodeEncodeError: 'charmap' codec can't encode characters

if you are using windows try to pass encoding='latin1', encoding='iso-8859-1' or encoding='cp1252' example:

csv_data = pd.read_csv(csvpath,encoding='iso-8859-1')
print(print(soup.encode('iso-8859-1')))

How to implement DrawerArrowToggle from Android appcompat v7 21 library

To answer the updated part of your question: to style the drawer icon/arrow, you have two options:

Style the arrow itself

To do this, override drawerArrowStyle in your theme like so:

<style name="AppBaseTheme" parent="Theme.AppCompat.Light">
    <item name="drawerArrowStyle">@style/MyTheme.DrawerArrowToggle</item>
</style>
<style name="MyTheme.DrawerArrowToggle" parent="Widget.AppCompat.DrawerArrowToggle">
    <item name="color">@android:color/holo_purple</item>
    <!-- ^ this will make the icon purple -->
</style>

This is probably not what you want, because the ActionBar itself should have consistent styling with the arrow, so, most probably, you want the option two:

Theme the ActionBar/Toolbar

Override the android:actionBarTheme (actionBarTheme for appcompat) attribute of the global application theme with your own theme (which you probably should derive from ThemeOverlay.Material.ActionBar/ThemeOverlay.AppCompat.ActionBar) like so:

<style name="AppBaseTheme" parent="Theme.AppCompat.Light">
    <item name="actionBarTheme">@style/MyTheme.ActionBar</item>
</style>
<style name="MyTheme.ActionBar" parent="ThemeOverlay.AppCompat.ActionBar">
    <item name="android:textColorPrimary">@android:color/white</item>
    <!-- ^ this will make text and arrow white -->
    <!-- you can also override drawerArrowStyle here -->
</style>

An important note here is that when using a custom layout with a Toolbar instead of stock ActionBar implementation (e.g. if you're using the DrawerLayout-NavigationView-Toolbar combo to achieve the Material-style drawer effect where it's visible under translucent statusbar), the actionBarTheme attribute is obviosly not picked up automatically (because it's meant to be taken care of by the AppCompatActivity for the default ActionBar), so for your custom Toolbar don't forget to apply your theme manually:

<!--inside your custom layout with DrawerLayout
and NavigationView or whatever -->
<android.support.v7.widget.Toolbar
        ...
        app:theme="?actionBarTheme">

-- this will resolve to either AppCompat's default ThemeOverlay.AppCompat.ActionBar or your override if you set the attribute in your derived theme.

PS a little comment about the drawerArrowStyle override and the spinBars attribute -- which a lot of sources suggest should be set to true to get the drawer/arrow animation. Thing is, spinBars it is true by default in AppCompat (check out the Base.Widget.AppCompat.DrawerArrowToggle.Common style), you don't have to override actionBarTheme at all to get the animation working. You get the animation even if you do override it and set the attribute to false, it's just a different, less twirly animation. The important thing here is to use ActionBarDrawerToggle, it's what pulls in the fancy animated drawable.

append option to select menu?

You can also use insertAdjacentHTML function:

const select = document.querySelector('select')
const value = 'bmw'
const label = 'BMW'

select.insertAdjacentHTML('beforeend', `
  <option value="${value}">${label}</option>
`)

ORA-01652 Unable to extend temp segment by in tablespace

I encountered the same error message but don't have any access to the table like "dba_free_space" because I am not a dba. I use some previous answers to check available space and I still have a lot of space. However, after reducing the full table scan as many as possible. The problem is solved. My guess is that Oracle uses temp table to store the full table scan data. It the data size exceeds the limit, it will show the error. Hope this helps someone with the same issue

Change the background color of a row in a JTable

This is basically as simple as repainting the table. I haven't found a way to selectively repaint just one row/column/cell however.

In this example, clicking on the button changes the background color for a row and then calls repaint.

public class TableTest {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        final Color[] rowColors = new Color[] {
                randomColor(), randomColor(), randomColor()
        };
        final JTable table = new JTable(3, 3);
        table.setDefaultRenderer(Object.class, new TableCellRenderer() {
            @Override
            public Component getTableCellRendererComponent(JTable table,
                    Object value, boolean isSelected, boolean hasFocus,
                    int row, int column) {
                JPanel pane = new JPanel();
                pane.setBackground(rowColors[row]);
                return pane;
            }
        });
        frame.setLayout(new BorderLayout());

        JButton btn = new JButton("Change row2's color");
        btn.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                rowColors[1] = randomColor();
                table.repaint();
            }
        });

        frame.add(table, BorderLayout.NORTH);
        frame.add(btn, BorderLayout.SOUTH);
        frame.pack();
        frame.setVisible(true);
    }

    private static Color randomColor() {
        Random rnd = new Random();
        return new Color(rnd.nextInt(256),
                rnd.nextInt(256), rnd.nextInt(256));
    }
}

Get specific ArrayList item

Try:

ArrayListname.get(index);

Where index is the position in the index and ArrayListname is the name of the Arraylist as in your case is mainList.

How can I generate an INSERT script for an existing SQL Server table that includes all stored rows?

Yes, use the commercial but inexpensive SSMS Tools Pack addin which has a nifty "Generate Insert statements from resultsets, tables or database" feature

Keyboard shortcut to change font size in Eclipse?

Take a look at this project: http://code.google.com/p/tarlog-plugins/downloads/detail?name=tarlog.eclipse.plugins_1.4.2.jar&can=2&q=

It has some other features, but most importantly, it has Ctrl++ and Ctrl+- to change the font size, it's awesome.

Creating a pandas DataFrame from columns of other DataFrames with similar indexes

What you ask for is the join operation. With the how argument, you can define how unique indices are handled. Here, some article, which looks helpful concerning this point. In the example below, I left out cosmetics (like renaming columns) for simplicity.

Code

import numpy as np
import pandas as pd
df1 = pd.DataFrame(np.random.randn(5,3), index=pd.date_range('01/02/2014',periods=5,freq='D'), columns=['a','b','c'] )
df2 = pd.DataFrame(np.random.randn(8,3), index=pd.date_range('01/01/2014',periods=8,freq='D'), columns=['a','b','c'] )

df3 = df1.join(df2, how='outer', lsuffix='_df1', rsuffix='_df2')
print(df3)

Output

               a_df1     b_df1     c_df1     a_df2     b_df2     c_df2
2014-01-01       NaN       NaN       NaN  0.109898  1.107033 -1.045376
2014-01-02  0.573754  0.169476 -0.580504 -0.664921 -0.364891 -1.215334
2014-01-03 -0.766361 -0.739894 -1.096252  0.962381 -0.860382 -0.703269
2014-01-04  0.083959 -0.123795 -1.405974  1.825832 -0.580343  0.923202
2014-01-05  1.019080 -0.086650  0.126950 -0.021402 -1.686640  0.870779
2014-01-06 -1.036227 -1.103963 -0.821523 -0.943848 -0.905348  0.430739
2014-01-07       NaN       NaN       NaN  0.312005  0.586585  1.531492
2014-01-08       NaN       NaN       NaN -0.077951 -1.189960  0.995123

Bootstrap: Position of dropdown menu relative to navbar item

If you want to display the menu up, just add the class "dropup"
and remove the class "dropdown" if exists from the same div.

<div class="btn-group dropup">

enter image description here

How to select an element by classname using jqLite?

If elem.find() is not working for you, check that you are including JQuery script before angular script....

repository element was not specified in the POM inside distributionManagement element or in -DaltDep loymentRepository=id::layout::url parameter

The issue is fixed by adding repository url under distributionManagement tab in main pom.xml.

Jenkin maven goal : clean deploy -U -Dmaven.test.skip=true

<distributionManagement>
    <repository>
        <id>releases</id>
        <url>http://domain:port/content/repositories/releases</url>
    </repository>
    <snapshotRepository>
        <id>snapshots</id>
        <url>http://domain:port/content/repositories/snapshots</url>
    </snapshotRepository>
</distributionManagement>

How to sort ArrayList<Long> in decreasing order?

Using List.sort() and Comparator.comparingLong()

numberList.sort(Comparator.comparingLong(x -> -x));

How do you execute an arbitrary native command from a string?

Invoke-Expression, also aliased as iex. The following will work on your examples #2 and #3:

iex $command

Some strings won't run as-is, such as your example #1 because the exe is in quotes. This will work as-is, because the contents of the string are exactly how you would run it straight from a Powershell command prompt:

$command = 'C:\somepath\someexe.exe somearg'
iex $command

However, if the exe is in quotes, you need the help of & to get it running, as in this example, as run from the commandline:

>> &"C:\Program Files\Some Product\SomeExe.exe" "C:\some other path\file.ext"

And then in the script:

$command = '"C:\Program Files\Some Product\SomeExe.exe" "C:\some other path\file.ext"'
iex "& $command"

Likely, you could handle nearly all cases by detecting if the first character of the command string is ", like in this naive implementation:

function myeval($command) {
    if ($command[0] -eq '"') { iex "& $command" }
    else { iex $command }
}

But you may find some other cases that have to be invoked in a different way. In that case, you will need to either use try{}catch{}, perhaps for specific exception types/messages, or examine the command string.

If you always receive absolute paths instead of relative paths, you shouldn't have many special cases, if any, outside of the 2 above.

Multi-Line Comments in Ruby?

#!/usr/bin/env ruby

=begin
Between =begin and =end, any number
of lines may be written. All of these
lines are ignored by the Ruby interpreter.
=end

puts "Hello world!"

Is there a way to do repetitive tasks at intervals?

I use the following code:

package main

import (
    "fmt"
    "time"
)

func main() {
    now := time.Now()
    fmt.Println("\nToday:", now)

    after := now.Add(1 * time.Minute)
    fmt.Println("\nAdd 1 Minute:", after)

    for {
        fmt.Println("test")
        time.Sleep(10 * time.Second)

        now = time.Now()

        if now.After(after) {
            break
        }
    }

    fmt.Println("done")
}

It is more simple and works fine to me.

Android + Pair devices via bluetooth programmatically

The Best way is do not use any pairing code. Instead of onClick go to other function or other class where You create the socket using UUID.
Android automatically pops up for pairing if already not paired.

or see this link for better understanding

Below is code for the same:

private OnItemClickListener mDeviceClickListener = new OnItemClickListener() {
    public void onItemClick(AdapterView<?> av, View v, int arg2, long arg3) {
        // Cancel discovery because it's costly and we're about to connect
        mBtAdapter.cancelDiscovery();

        // Get the device MAC address, which is the last 17 chars in the View
        String info = ((TextView) v).getText().toString();
        String address = info.substring(info.length() - 17);

        // Create the result Intent and include the MAC address
        Intent intent = new Intent();
        intent.putExtra(EXTRA_DEVICE_ADDRESS, address);

        // Set result and finish this Activity
        setResult(Activity.RESULT_OK, intent);

      // **add this 2 line code** 
       Intent myIntent = new Intent(view.getContext(), Connect.class);
        startActivityForResult(myIntent, 0);

        finish();
    }
};

Connect.java file is :

public class Connect extends Activity {
private static final String TAG = "zeoconnect";
private ByteBuffer localByteBuffer;
 private InputStream in;
 byte[] arrayOfByte = new byte[4096];
 int bytes;


  public BluetoothDevice mDevice;



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



              try {
                setup();
            } catch (ZeoMessageException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (ZeoMessageParseException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            }

 private void setup() throws ZeoMessageException, ZeoMessageParseException  {
    // TODO Auto-generated method stub

        getApplicationContext().registerReceiver(receiver,
                    new IntentFilter(BluetoothDevice.ACTION_ACL_CONNECTED));
        getApplicationContext().registerReceiver(receiver,
                    new IntentFilter(BluetoothDevice.ACTION_ACL_DISCONNECTED));

            BluetoothDevice zee = BluetoothAdapter.getDefaultAdapter().
                    getRemoteDevice("**:**:**:**:**:**");// add device mac adress

            try {
                sock = zee.createRfcommSocketToServiceRecord(
                         UUID.fromString("*******************")); // use unique UUID
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }

            Log.d(TAG, "++++ Connecting");
            try {
                sock.connect();
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            Log.d(TAG, "++++ Connected");


            try {
                in = sock.getInputStream();
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }

              Log.d(TAG, "++++ Listening...");

              while (true) {

                  try {
                      bytes = in.read(arrayOfByte);
                      Log.d(TAG, "++++ Read "+ bytes +" bytes");  
                    } catch (IOException e1) {
                        // TODO Auto-generated catch block
                        e1.printStackTrace();
                }
                        Log.d(TAG, "++++ Done: test()"); 

                        }} 




 private static final LogBroadcastReceiver receiver = new LogBroadcastReceiver();
    public static class LogBroadcastReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context paramAnonymousContext, Intent paramAnonymousIntent) {
            Log.d("ZeoReceiver", paramAnonymousIntent.toString());
            Bundle extras = paramAnonymousIntent.getExtras();
            for (String k : extras.keySet()) {
                Log.d("ZeoReceiver", "    Extra: "+ extras.get(k).toString());
            }
        }


    };

    private BluetoothSocket sock;
    @Override
    public void onDestroy() {
        getApplicationContext().unregisterReceiver(receiver);
        if (sock != null) {
            try {
                sock.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        super.onDestroy();
    }
 }

Split pandas dataframe in two if it has more than 10 rows

Below is a simple function implementation which splits a DataFrame to chunks and a few code examples:

import pandas as pd

def split_dataframe_to_chunks(df, n):
    df_len = len(df)
    count = 0
    dfs = []

    while True:
        if count > df_len-1:
            break

        start = count
        count += n
        #print("%s : %s" % (start, count))
        dfs.append(df.iloc[start : count])
    return dfs


# Create a DataFrame with 10 rows
df = pd.DataFrame([i for i in range(10)])

# Split the DataFrame to chunks of maximum size 2
split_df_to_chunks_of_2 = split_dataframe_to_chunks(df, 2)
print([len(i) for i in split_df_to_chunks_of_2])
# prints: [2, 2, 2, 2, 2]

# Split the DataFrame to chunks of maximum size 3
split_df_to_chunks_of_3 = split_dataframe_to_chunks(df, 3)
print([len(i) for i in split_df_to_chunks_of_3])
# prints [3, 3, 3, 1]

Split string and get first value only

string valueStr = "title, genre, director, actor";
var vals = valueStr.Split(',')[0];

vals will give you the title

SELECT only rows that contain only alphanumeric characters in MySQL

Change the REGEXP to Like

SELECT * FROM table_name WHERE column_name like '%[^a-zA-Z0-9]%'

this one works fine

Null vs. False vs. 0 in PHP

The differences between these values always come down to detailed language-specific rules. What you learn for PHP isn't necessarily true for Python, or Perl, or C, etc. While it is valuable to learn the rules for the language(s) you're working with, relying on them too much is asking for trouble. The trouble comes when the next programmer needs to maintain your code and you've used some construct that takes advantage of some little detail of Null vs. False (for example). Your code should look correct (and conversely, wrong code should look wrong).

How can I make a "color map" plot in matlab?

I also suggest using contourf(Z). For my problem, I wanted to visualize a 3D histogram in 2D, but the contours were too smooth to represent a top view of histogram bars.

So in my case, I prefer to use jucestain's answer. The default shading faceted of pcolor() is more suitable. However, pcolor() does not use the last row and column of the plotted matrix. For this, I used the padarray() function:

pcolor(padarray(Z,[1 1],0,'post'))

Sorry if that is not really related to the original post

How can I calculate divide and modulo for integers in C#?

Read two integers from the user. Then compute/display the remainder and quotient,

// When the larger integer is divided by the smaller integer
Console.WriteLine("Enter integer 1 please :");
double a5 = double.Parse(Console.ReadLine());
Console.WriteLine("Enter integer 2 please :");
double b5 = double.Parse(Console.ReadLine());

double div = a5 / b5;
Console.WriteLine(div);

double mod = a5 % b5;
Console.WriteLine(mod);

Console.ReadLine();

How to show changed file name only with git log?

I stumbled in here looking for a similar answer without the "git log" restriction. The answers here didn't give me what I needed but this did so I'll add it in case others find it useful:

git diff --name-only

You can also couple this with standard commit pointers to see what has changed since a particular commit:

git diff --name-only HEAD~3
git diff --name-only develop
git diff --name-only 5890e37..ebbf4c0

This succinctly provides file names only which is great for scripting. For example:

git diff --name-only develop | while read changed_file; do echo "This changed from the develop version: $changed_file"; done

#OR

git diff --name-only develop | xargs tar cvf changes.tar

Is unsigned integer subtraction defined behavior?

When you work with unsigned types, modular arithmetic (also known as "wrap around" behavior) is taking place. To understand this modular arithmetic, just have a look at these clocks:

enter image description here

9 + 4 = 1 (13 mod 12), so to the other direction it is: 1 - 4 = 9 (-3 mod 12). The same principle is applied while working with unsigned types. If the result type is unsigned, then modular arithmetic takes place.


Now look at the following operations storing the result as an unsigned int:

unsigned int five = 5, seven = 7;
unsigned int a = five - seven;      // a = (-2 % 2^32) = 4294967294 

int one = 1, six = 6;
unsigned int b = one - six;         // b = (-5 % 2^32) = 4294967291

When you want to make sure that the result is signed, then stored it into signed variable or cast it to signed. When you want to get the difference between numbers and make sure that the modular arithmetic will not be applied, then you should consider using abs() function defined in stdlib.h:

int c = five - seven;       // c = -2
int d = abs(five - seven);  // d =  2

Be very careful, especially while writing conditions, because:

if (abs(five - seven) < seven)  // = if (2 < 7)
    // ...

if (five - seven < -1)          // = if (-2 < -1)
    // ...

if (one - six < 1)              // = if (-5 < 1)
    // ...

if ((int)(five - seven) < 1)    // = if (-2 < 1)
    // ...

but

if (five - seven < 1)   // = if ((unsigned int)-2 < 1) = if (4294967294 < 1)
    // ...

if (one - six < five)   // = if ((unsigned int)-5 < 5) = if (4294967291 < 5)
    // ...

How should I tackle --secure-file-priv in MySQL?

I'm working on MySQL5.7.11 on Debian, the command that worked for me to see the directory is:

mysql> SELECT @@global.secure_file_priv;

Remove warning messages in PHP

If you want to suppress the warnings and some other error types (for example, notices) while displaying all other errors, you can do:

error_reporting(E_ALL & ~E_WARNING & ~E_NOTICE);

Delete all the records

When the table is very large, it's better to delete table itself with drop table TableName and recreate it, if one has create table query; rather than deleting records one by one, using delete from statement because that can be time consuming.

htaccess Access-Control-Allow-Origin

Make sure you don't have a redirect happening. This can happen if you don't include the trailing slash in the URL.

See this answer for more detail – https://stackoverflow.com/a/27872891/614524

Solutions for INSERT OR UPDATE on SQL Server

MS SQL Server 2008 introduces the MERGE statement, which I believe is part of the SQL:2003 standard. As many have shown it is not a big deal to handle one row cases, but when dealing with large datasets, one needs a cursor, with all the performance problems that come along. The MERGE statement will be much welcomed addition when dealing with large datasets.

Change MySQL default character set to UTF-8 in my.cnf?

All settings listed here are correct, but here are the most optimal and sufficient solution:

[mysqld]
init_connect='SET collation_connection = utf8_unicode_ci'
character-set-server = utf8
collation-server = utf8_unicode_ci

[client]
default-character-set = utf8

Add these to /etc/mysql/my.cnf.

Please note, I choose utf8_unicode_ci type of collation due to the performance issue.

The result is:

mysql> SHOW VARIABLES LIKE 'character%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8                       |
| character_set_connection | utf8                       |
| character_set_database   | utf8                       |
| character_set_filesystem | binary                     |
| character_set_results    | utf8                       |
| character_set_server     | utf8                       |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+

mysql> SHOW VARIABLES LIKE 'collation%';
+----------------------+-----------------+
| Variable_name        | Value           |
+----------------------+-----------------+
| collation_connection | utf8_unicode_ci |
| collation_database   | utf8_unicode_ci |
| collation_server     | utf8_unicode_ci |
+----------------------+-----------------+

And this is when you connect as non-SUPER user!

For example, the difference between connection as SUPER and non-SUPER user (of course in case of utf8_unicode_ci collation):

user with SUPER priv.:

mysql> SHOW VARIABLES LIKE 'collation%';
+----------------------+-----------------+
| Variable_name        | Value           |
+----------------------+-----------------+
| collation_connection | utf8_general_ci | <---
| collation_database   | utf8_unicode_ci |
| collation_server     | utf8_unicode_ci |
+----------------------+-----------------+

user with non-SUPER priv.:

mysql> SHOW VARIABLES LIKE 'collation%';
+----------------------+-----------------+
| Variable_name        | Value           |
+----------------------+-----------------+
| collation_connection | utf8_unicode_ci |
| collation_database   | utf8_unicode_ci |
| collation_server     | utf8_unicode_ci |
+----------------------+-----------------+

I wrote a comprehensive article (rus) explaining in details why you should use one or the other option. All types of Character Sets and Collations are considered: for server, for database, for connection, for table and even for column.

I hope this and the article will help to clarify unclear moments.

Strip first and last character from C string

To "remove" the 1st character point to the second character:

char mystr[] = "Nmy stringP";
char *p = mystr;
p++; /* 'N' is not in `p` */

To remove the last character replace it with a '\0'.

p[strlen(p)-1] = 0; /* 'P' is not in `p` (and it isn't in `mystr` either) */

clear data inside text file in c++

If you set the trunc flag.

#include<fstream>

using namespace std;

fstream ofs;

int main(){
ofs.open("test.txt", ios::out | ios::trunc);
ofs<<"Your content here";
ofs.close(); //Using microsoft incremental linker version 14
}

I tested this thouroughly for my own needs in a common programming situation I had. Definitely be sure to preform the ".close();" operation. If you don't do this there is no telling whether or not you you trunc or just app to the begging of the file. Depending on the file type you might just append over the file which depending on your needs may not fullfill its purpose. Be sure to call ".close();" explicity on the fstream you are trying to replace.

Limit length of characters in a regular expression?

If you want numbers from 1 up to 100:

100|[1-9]\d?

How to replace � in a string

As others have said, you posted 3 characters instead of one. I suggest you run this little snippet of code to see what's actually in your string:

public static void dumpString(String text)
{
    for (int i=0; i < text.length(); i++)
    {
        System.out.println("U+" + Integer.toString(text.charAt(i), 16) 
                           + " " + text.charAt(i));
    }
}

If you post the results of that, it'll be easier to work out what's going on. (I haven't bothered padding the string - we can do that by inspection...)

XPath: Get parent node from child node

Just as an alternative, you can use ancestor.

//*[title="50"]/ancestor::store

It's more powerful than parent since it can get even the grandparent or great great grandparent

How to navigate to a section of a page

Use HTML's anchors:

Main Page:

<a href="sample.html#sushi">Sushi</a>
<a href="sample.html#bbq">BBQ</a>

Sample Page:

<div id='sushi'><a name='sushi'></a></div>
<div id='bbq'><a name='bbq'></a></div>

How to store(bitmap image) and retrieve image from sqlite database in android?

If you are working with Android's MediaStore database, here is how to store an image and then display it after it is saved.

on button click write this

 Intent in = new Intent(Intent.ACTION_PICK,
                    android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            in.putExtra("crop", "true");
            in.putExtra("outputX", 100);
            in.putExtra("outputY", 100);
            in.putExtra("scale", true);
            in.putExtra("return-data", true);

            startActivityForResult(in, 1);

then do this in your activity

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        // TODO Auto-generated method stub
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == 1 && resultCode == RESULT_OK && data != null) {

            Bitmap bmp = (Bitmap) data.getExtras().get("data");

            img.setImageBitmap(bmp);
            btnadd.requestFocus();

            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            bmp.compress(Bitmap.CompressFormat.JPEG, 100, baos);
            byte[] b = baos.toByteArray();
            String encodedImageString = Base64.encodeToString(b, Base64.DEFAULT);

            byte[] bytarray = Base64.decode(encodedImageString, Base64.DEFAULT);
            Bitmap bmimage = BitmapFactory.decodeByteArray(bytarray, 0,
                    bytarray.length);

        }

    }

Very Long If Statement in Python

Here is the example directly from PEP 8 on limiting line length:

class Rectangle(Blob):

    def __init__(self, width, height,
                 color='black', emphasis=None, highlight=0):
        if (width == 0 and height == 0 and
                color == 'red' and emphasis == 'strong' or
                highlight > 100):
            raise ValueError("sorry, you lose")
        if width == 0 and height == 0 and (color == 'red' or
                                           emphasis is None):
            raise ValueError("I don't think so -- values are %s, %s" %
                             (width, height))
        Blob.__init__(self, width, height,
                      color, emphasis, highlight)

Is it possible to set the stacking order of pseudo-elements below their parent element?

Speaking with regard to the spec (http://www.w3.org/TR/CSS2/zindex.html), since a.someSelector is positioned it creates a new stacking context that its children can't break out of. Leave a.someSelector unpositioned and then child a.someSelector:after may be positioned in the same context as a.someSelector.

How to get main window handle from process id?

I checked how .NET determines the main window.

My finding showed that it also uses EnumWindows().

This code should do it similarly to the .NET way:

struct handle_data {
    unsigned long process_id;
    HWND window_handle;
};

HWND find_main_window(unsigned long process_id)
{
    handle_data data;
    data.process_id = process_id;
    data.window_handle = 0;
    EnumWindows(enum_windows_callback, (LPARAM)&data);
    return data.window_handle;
}

BOOL CALLBACK enum_windows_callback(HWND handle, LPARAM lParam)
{
    handle_data& data = *(handle_data*)lParam;
    unsigned long process_id = 0;
    GetWindowThreadProcessId(handle, &process_id);
    if (data.process_id != process_id || !is_main_window(handle))
        return TRUE;
    data.window_handle = handle;
    return FALSE;   
}

BOOL is_main_window(HWND handle)
{   
    return GetWindow(handle, GW_OWNER) == (HWND)0 && IsWindowVisible(handle);
}

Get contentEditable caret index position

If you set the editable div style to "display:inline-block; white-space: pre-wrap" you don't get new child divs when you enter a new line, you just get LF character (i.e. &#10);.

_x000D_
_x000D_
function showCursPos(){
    selection = document.getSelection();
    childOffset = selection.focusOffset;
    const range = document.createRange();
    eDiv = document.getElementById("eDiv");
    range.setStart(eDiv, 0);
    range.setEnd(selection.focusNode, childOffset);
    var sHtml = range.toString();
    p = sHtml.length; 
    sHtml=sHtml.replace(/(\r)/gm, "\\r");
    sHtml=sHtml.replace(/(\n)/gm, "\\n");
    document.getElementById("caretPosHtml").value=p;
    document.getElementById("exHtml").value=sHtml;   
  }
_x000D_
click/type in div below:
<br>
<div contenteditable name="eDiv" id="eDiv"  
     onkeyup="showCursPos()" onclick="showCursPos()" 
     style="width: 10em; border: 1px solid; display:inline-block; white-space: pre-wrap; "
     >123&#13;&#10;456&#10;789</div>
<p>
html caret position:<br> <input type="text" id="caretPosHtml">
<p>  
html from start of div:<br> <input type="text" id="exHtml">
_x000D_
_x000D_
_x000D_

What I noticed was when you press "enter" in the editable div, it creates a new node, so the focusOffset resets to zero. This is why I've had to add a range variable, and extend it from the child nodes' focusOffset back to the start of eDiv (and thus capturing all text in-between).

Can we define min-margin and max-margin, max-padding and min-padding in css?

Comming late to the party, as said above there unfortunately is no such thing as max-margin. A sollution that helped me is to place a div above the item you want to have the max-margin applied to.

<body style="width:90vw; height:90vh;">
    <div name="parrentdiv/body" style="width:300px; height:100%; background-color: blue">
        <div name="margin top" style="width:300px; height:50%; min-height:200px; background-color: red"></div>
        <div name="item" style="width:300px; height:180px; background-color: lightgrey">Hello World!</div>
    </div>
</body>

Run above coded snippet in full page and resize the window to see this working. The lightgreypart will have the margin-top of 50% and a 'min-margin-top' of 200px. This margin is the red div (wich you can hide with display: none; if you want to). The blue part is what's left of the body.

I hope this will help people with the same problem in the future.

How do I loop through children objects in javascript?

The backwards compatible version (IE9+) is

var parent = document.querySelector(selector);
Array.prototype.forEach.call(parent.children, function(child, index){
  // Do stuff
});

The es6 way is

const parent = document.querySelector(selector);
Array.from(parent.children).forEach((child, index) => {
  // Do stuff
});

How to add a class to body tag?

I had the same problem,

<body id="body">

Add an ID tag to the body:

$('#body').attr('class',json.class); // My class comes from Ajax/JSON, but change it to whatever you require.

Then switch the class for the body's using the id. This has been tested in Chrome, Internet Explorer, and Safari.

How to display list items as columns?

If you take a look at the following example - it uses fixed width columns, and I think this is the behavior requested.

http://www.vanderlee.com/martijn/demo/column/

If the bottom example is the same as the top, you don't need the jquery column plugin.

_x000D_
_x000D_
ul{margin:0; padding:0;}_x000D_
_x000D_
#native {_x000D_
  -webkit-column-width: 150px;_x000D_
  -moz-column-width: 150px;_x000D_
  -o-column-width: 150px;_x000D_
  -ms-column-width: 150px;_x000D_
  column-width: 150px;_x000D_
  _x000D_
  -webkit-column-rule-style: solid;_x000D_
  -moz-column-rule-style: solid;_x000D_
  -o-column-rule-style: solid;_x000D_
  -ms-column-rule-style: solid;_x000D_
  column-rule-style: solid;_x000D_
}
_x000D_
<div id="native">_x000D_
  <ul>_x000D_
    <li>1</li>_x000D_
    <li>2</li>_x000D_
    <li>3</li>_x000D_
    <li>4</li>_x000D_
    <li>5</li>_x000D_
    <li>6</li>_x000D_
    <li>7</li>_x000D_
    <li>8</li>_x000D_
    <li>9</li>_x000D_
    <li>10</li>_x000D_
    <li>11</li>_x000D_
    <li>12</li>_x000D_
    <li>13</li>_x000D_
    <li>14</li>_x000D_
    <li>15</li>_x000D_
    <li>16</li>_x000D_
    <li>17</li>_x000D_
    <li>18</li>_x000D_
    <li>19</li>_x000D_
  </ul>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to convert char to integer in C?

The standard function atoi() will likely do what you want.

A simple example using "atoi":

#include <unistd.h>

int main(int argc, char *argv[])
{
    int useconds = atoi(argv[1]); 
    usleep(useconds);
}

How to compile C++ under Ubuntu Linux?

Use g++. And make sure you have the relevant libraries installed.

Reading Data From Database and storing in Array List object

You have to create a new customer object in every iteration and then add that newly created object into the ArrayList at the lase of your iteration.

How can I get a precise time, for example in milliseconds in Objective-C?

Also, here is how to calculate a 64-bit NSNumber initialized with the Unix epoch in milliseconds, in case that is how you want to store it in CoreData. I needed this for my app which interacts with a system that stores dates this way.

  + (NSNumber*) longUnixEpoch {
      return [NSNumber numberWithLongLong:[[NSDate date] timeIntervalSince1970] * 1000];
  }

npm check and update package if needed

One easy step:

$ npm i -g npm-check-updates && ncu -u && npm i

That is all. All of the package versions in package.json will be the latest major versions.

Edit:

What is happening here?

  1. Installing a package that checks updates for you.

  2. Use this package to update all package versions in your package.json (-u is short for --updateAll).

  3. Install all of the new versions of the packages.

How to import jquery using ES6 syntax?

If you are not using any JS build tools/NPM, then you can directly include Jquery as:

import  'https://code.jquery.com/jquery-1.12.4.min.js';
const $ = window.$;

You may skip import(Line 1) if you already included jquery using script tag under head.

Conflict with dependency 'com.android.support:support-annotations'. Resolved versions for app (23.1.0) and test app (23.0.1) differ

I was getting the same error today:

Error:Execution failed for task ':app:preDebugAndroidTestBuild'.> Conflict with dependency 'com.android.support:support-annotations' in project ':app'. Resolved versions for app (26.1.0) and test app (27.1.1) differ.

What I did:

  • I simply updated all my dependencies to 27.1.1 instead of 26.1.0
  • Also, updated my compileSdkVersion 27 and targetSdkVersion 27 which were 26 earlier

And com.android.support:support-annotations error was gone!

For Ref:

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support.constraint:constraint-layout:1.1.0'
    implementation 'com.android.support:design:27.1.1'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

ImportError: cannot import name

The problem is that you have a circular import: in app.py

from mod_login import mod_login

in mod_login.py

from app import app

This is not permitted in Python. See Circular import dependency in Python for more info. In short, the solution are

  • either gather everything in one big file
  • delay one of the import using local import

How to wait for async method to complete?

just put Wait() to wait until task completed

GetInputReportViaInterruptTransfer().Wait();

How do I connect to a MySQL Database in Python?

Stop Using MySQLDb if you want to avoid installing mysql headers just to access mysql from python.

Use pymysql. It does all of what MySQLDb does, but it was implemented purely in Python with NO External Dependencies. This makes the installation process on all operating systems consistent and easy. pymysql is a drop in replacement for MySQLDb and IMHO there is no reason to ever use MySQLDb for anything... EVER! - PTSD from installing MySQLDb on Mac OSX and *Nix systems, but that's just me.

Installation

pip install pymysql

That's it... you are ready to play.

Example usage from pymysql Github repo

import pymysql.cursors
import pymysql

# Connect to the database
connection = pymysql.connect(host='localhost',
                             user='user',
                             password='passwd',
                             db='db',
                             charset='utf8mb4',
                             cursorclass=pymysql.cursors.DictCursor)

try:
    with connection.cursor() as cursor:
        # Create a new record
        sql = "INSERT INTO `users` (`email`, `password`) VALUES (%s, %s)"
        cursor.execute(sql, ('[email protected]', 'very-secret'))

    # connection is not autocommit by default. So you must commit to save
    # your changes.
    connection.commit()

    with connection.cursor() as cursor:
        # Read a single record
        sql = "SELECT `id`, `password` FROM `users` WHERE `email`=%s"
        cursor.execute(sql, ('[email protected]',))
        result = cursor.fetchone()
        print(result)
finally:
    connection.close()

ALSO - Replace MySQLdb in existing code quickly and transparently

If you have existing code that uses MySQLdb, you can easily replace it with pymysql using this simple process:

# import MySQLdb << Remove this line and replace with:
import pymysql
pymysql.install_as_MySQLdb()

All subsequent references to MySQLdb will use pymysql transparently.

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

I used to have this problem sometimes, the solution was to change the USB cable to a new one

Example: Communication between Activity and Service using Messaging

Message msg = Message.obtain(null, 2, 0, 0);
                    Bundle bundle = new Bundle();
                    bundle.putString("url", url);
                    bundle.putString("names", names);
                    bundle.putString("captions",captions); 
                    msg.setData(bundle);

So you send it to the service. Afterward receive.

PHP Echo text Color

This is an old question, but no one responded to the question regarding centering text in a terminal.

/**
 * Centers a string of text in a terminal window
 *
 * @param string $text The text to center
 * @param string $pad_string If set, the string to pad with (eg. '=' for a nice header)
 *
 * @return string The padded result, ready to echo
 */
function center($text, $pad_string = ' ') {
    $window_size = (int) `tput cols`;
    return str_pad($text, $window_size, $pad_string, STR_PAD_BOTH)."\n";
}

echo center('foo');
echo center('bar baz', '=');

HTML5 image icon to input placeholder

<html>
<head>
<style> 
input[type=text] {
    width: 50%;
    box-sizing: border-box;
    border: 2px solid #ccc;
    border-radius: 4px;
    font-size: 16px;
    background-color: white;
    background-image: url('searchicon.png');
    background-position: 10px 10px; 
    background-repeat: no-repeat;
    padding: 12px 20px 12px 40px;
}
</style>
</head>
<body>

<p>Input with icon:</p>

<form>
  <input type="text" name="search" placeholder="Search..">
</form>

</body>
</html>

How to list processes attached to a shared memory segment in linux?

I don't think you can do this with the standard tools. You can use ipcs -mp to get the process ID of the last process to attach/detach but I'm not aware of how to get all attached processes with ipcs.

With a two-process-attached segment, assuming they both stayed attached, you can possibly figure out from the creator PID cpid and last-attached PID lpid which are the two processes but that won't scale to more than two processes so its usefulness is limited.

The cat /proc/sysvipc/shm method seems similarly limited but I believe there's a way to do it with other parts of the /proc filesystem, as shown below:

When I do a grep on the procfs maps for all processes, I get entries containing lines for the cpid and lpid processes.

For example, I get the following shared memory segment from ipcs -m:

------ Shared Memory Segments --------
key        shmid      owner      perms      bytes      nattch     status      
0x00000000 123456     pax        600        1024       2          dest

and, from ipcs -mp, the cpid is 3956 and the lpid is 9999 for that given shared memory segment (123456).

Then, with the command grep 123456 /proc/*/maps, I see:

/proc/3956/maps: blah blah blah 123456 /SYSV000000 (deleted)
/proc/9999/maps: blah blah blah 123456 /SYSV000000 (deleted)

So there is a way to get the processes that attached to it. I'm pretty certain that the dest status and (deleted) indicator are because the creator has marked the segment for destruction once the final detach occurs, not that it's already been destroyed.

So, by scanning of the /proc/*/maps "files", you should be able to discover which PIDs are currently attached to a given segment.

How do I escape ampersands in XML so they are rendered as entities in HTML?

Use CDATA tags:

 <![CDATA[
   This is some text with ampersands & other funny characters. >>
 ]]>

Get width/height of SVG element

This is the consistent cross-browser way I found:

var heightComponents = ['height', 'paddingTop', 'paddingBottom', 'borderTopWidth', 'borderBottomWidth'],
    widthComponents = ['width', 'paddingLeft', 'paddingRight', 'borderLeftWidth', 'borderRightWidth'];

var svgCalculateSize = function (el) {

    var gCS = window.getComputedStyle(el), // using gCS because IE8- has no support for svg anyway
        bounds = {
            width: 0,
            height: 0
        };

    heightComponents.forEach(function (css) { 
        bounds.height += parseFloat(gCS[css]);
    });
    widthComponents.forEach(function (css) {
        bounds.width += parseFloat(gCS[css]);
    });
    return bounds;
};

pip or pip3 to install packages for Python 3?

In my system, I use the update alternatives.

sudo update-alternatives --install /usr/bin/pip pip /usr/bin/pip3 1
sudo update-alternatives --install /usr/bin/pip pip /usr/bin/pip2 2

If I want to switch between them I use the following command.

sudo update-alternatives --config pip

Note: The 1st line is enough if you have only pip3 installed and not pip2.

How do I print the full value of a long string in gdb?

set print elements 0

From the GDB manual:

set print elements number-of-elements
Set a limit on how many elements of an array GDB will print. If GDB is printing a large array, it stops printing after it has printed the number of elements set by the set print elements command. This limit also applies to the display of strings. When GDB starts, this limit is set to 200. Setting number-of-elements to zero means that the printing is unlimited.

Converting Pandas dataframe into Spark dataframe error

I have tried this with your data and it is working :

%pyspark
import pandas as pd
from pyspark.sql import SQLContext
print sc
df = pd.read_csv("test.csv")
print type(df)
print df
sqlCtx = SQLContext(sc)
sqlCtx.createDataFrame(df).show()

'Access-Control-Allow-Origin' issue when API call made from React (Isomorphic app)

I was having the same problem with the fetch command. A quick look at the docs from here tells us this:

If the server you are requesting from doesn't support CORS, you should get an error in the console indicating that the cross-origin request is blocked due to the CORS Access-Control-Allow-Origin header being missing.

You can use no-cors mode to request opaque resources.

fetch('https://bar.com/data.json', {
  mode: 'no-cors' // 'cors' by default
})
.then(function(response) {
  // Do something with response
});

Continue For loop

I sometimes do a double do loop:

Do

    Do

        If I_Don't_Want_to_Finish_This_Loop Then Exit Do

        Exit Do

    Loop

Loop Until Done

This avoids having "goto spaghetti"

Where is the Global.asax.cs file?

That's because you created a Web Site instead of a Web Application. The cs/vb files can only be seen in a Web Application, but in a website you can't have a separate cs/vb file.

Edit: In the website you can add a cs file behavior like..

<%@ Application CodeFile="Global.asax.cs" Inherits="ApplicationName.MyApplication" Language="C#" %>

~/Global.asax.cs:

namespace ApplicationName
{
    public partial class MyApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
        }
    }
}

Need a good hex editor for Linux

I am a VIMer. I can do some rare Hex edits with:

  • :%!xxd to switch into hex mode

  • :%!xxd -r to exit from hex mode

But I strongly recommend ht

apt-cache show ht

Package: ht
Version: 2.0.18-1
Installed-Size: 1780
Maintainer: Alexander Reichle-Schmehl <[email protected]>

Homepage: http://hte.sourceforge.net/

Note: The package is called ht, whereas the executable is named hte after the package was installed.

  1. Supported file formats
    • common object file format (COFF/XCOFF32)
    • executable and linkable format (ELF)
    • linear executables (LE)
    • standard DO$ executables (MZ)
    • new executables (NE)
    • portable executables (PE32/PE64)
    • java class files (CLASS)
    • Mach exe/link format (MachO)
    • X-Box executable (XBE)
    • Flat (FLT)
    • PowerPC executable format (PEF)
  2. Code & Data Analyser
    • finds branch sources and destinations recursively
    • finds procedure entries
    • creates labels based on this information
    • creates xref information
    • allows to interactively analyse unexplored code
    • allows to create/rename/delete labels
    • allows to create/edit comments
    • supports x86, ia64, alpha, ppc and java code
  3. Target systems
    • DJGPP
    • GNU/Linux
    • FreeBSD
    • OpenBSD
    • Win32

How to set timeout in Retrofit library?

You can set timeouts on the underlying HTTP client. If you don't specify a client, Retrofit will create one with default connect and read timeouts. To set your own timeouts, you need to configure your own client and supply it to the RestAdapter.Builder.

An option is to use the OkHttp client, also from Square.

1. Add the library dependency

In the build.gradle, include this line:

compile 'com.squareup.okhttp:okhttp:x.x.x'

Where x.x.x is the desired library version.

2. Set the client

For example, if you want to set a timeout of 60 seconds, do this way for Retrofit before version 2 and Okhttp before version 3 (FOR THE NEWER VERSIONS, SEE THE EDITS):

public RestAdapter providesRestAdapter(Gson gson) {
    final OkHttpClient okHttpClient = new OkHttpClient();
    okHttpClient.setReadTimeout(60, TimeUnit.SECONDS);
    okHttpClient.setConnectTimeout(60, TimeUnit.SECONDS);

    return new RestAdapter.Builder()
        .setEndpoint(BuildConfig.BASE_URL)
        .setConverter(new GsonConverter(gson))
        .setClient(new OkClient(okHttpClient))
        .build();
}

EDIT 1

For okhttp versions since 3.x.x, you have to set the dependency this way:

compile 'com.squareup.okhttp3:okhttp:x.x.x'

And set the client using the builder pattern:

final OkHttpClient okHttpClient = new OkHttpClient.Builder()
        .readTimeout(60, TimeUnit.SECONDS)
        .connectTimeout(60, TimeUnit.SECONDS)
        .build();

More info in Timeouts


EDIT 2

Retrofit versions since 2.x.x also uses the builder pattern, so change the return block above to this:

return new Retrofit.Builder()
    .baseUrl(BuildConfig.BASE_URL)
    .addConverterFactory(GsonConverterFactory.create())
    .client(okHttpClient)
    .build();

If using a code like my providesRestAdapter method, then change the method return type to Retrofit.

More info in Retrofit 2 — Upgrade Guide from 1.9


ps: If your minSdkVersion is greater than 8, you can use TimeUnit.MINUTES:

okHttpClient.setReadTimeout(1, TimeUnit.MINUTES);
okHttpClient.setConnectTimeout(1, TimeUnit.MINUTES);

For more details about the units, see TimeUnit.

Remove json element

if we want to remove one attribute say "firstName" from the array we can use map function along with delete as mentioned above

   var result= [
       {
           "FirstName": "Test1",
           "LastName":  "User",
       },
       {
           "FirstName": "user",
           "LastName":  "user",
       },
       {
           "FirstName": "Ropbert",
           "LastName":  "Jones",
       },
       {
           "FirstName": "hitesh",
           "LastName":  "prajapti",
       }
   ]

result.map( el=>{
    delete el["FirstName"]
})
console.log("OUT",result)

java.net.SocketException: Software caused connection abort: recv failed

This usually means that there was a network error, such as a TCP timeout. I would start by placing a sniffer (wireshark) on the connection to see if you can see any problems. If there is a TCP error, you should be able to see it. Also, you can check your router logs, if this is applicable. If wireless is involved anywhere, that is another source for these kind of errors.

Are SSL certificates bound to the servers ip address?

The SSL certificates are going to be bound to hostname rather than IP if they are setup in the standard way. Hence why it works at one site rather than the other.

Even if the servers share the same hostname they may well have two different certificates and hence WebSphere will have a certificate trust issue as it won't be able to recognise the certificate on the second server as it is different to the first.

Custom sort function in ng-repeat

The accepted solution only works on arrays, but not objects or associative arrays. Unfortunately, since Angular depends on the JavaScript implementation of array enumeration, the order of object properties cannot be consistently controlled. Some browsers may iterate through object properties lexicographically, but this cannot be guaranteed.

e.g. Given the following assignment:

$scope.cards = {
  "card2": {
    values: {
      opt1: 9,
      opt2: 12
    }
  },
  "card1": {
    values: {
      opt1: 9,
      opt2: 11
    }
  }
};

and the directive <ul ng-repeat="(key, card) in cards | orderBy:myValueFunction">, ng-repeat may iterate over "card1" prior to "card2", regardless of sort order.

To workaround this, we can create a custom filter to convert the object to an array, and then apply a custom sort function before returning the collection.

myApp.filter('orderByValue', function () {
  // custom value function for sorting
  function myValueFunction(card) {
    return card.values.opt1 + card.values.opt2;
  }

  return function (obj) {
    var array = [];
    Object.keys(obj).forEach(function (key) {
      // inject key into each object so we can refer to it from the template
      obj[key].name = key;
      array.push(obj[key]);
    });
    // apply a custom sorting function
    array.sort(function (a, b) {
      return myValueFunction(b) - myValueFunction(a);
    });
    return array;
  };
});

We cannot iterate over (key, value) pairings in conjunction with custom filters (since the keys for arrays are numerical indexes), so the template should be updated to reference the injected key names.

<ul ng-repeat="card in cards | orderByValue">
    <li>{{card.name}} {{value(card)}}</li>
</ul>

Here is a working fiddle utilizing a custom filter on an associative array: http://jsfiddle.net/av1mLpqx/1/

Reference: https://github.com/angular/angular.js/issues/1286#issuecomment-22193332

Select from one table where not in another

You can LEFT JOIN the two tables. If there is no corresponding row in the second table, the values will be NULL.

SELECT id FROM partmaster LEFT JOIN product_details ON (...) WHERE product_details.part_num IS NULL

How do I use T-SQL's Case/When?

declare @n int = 7,
    @m int = 3;

select 
    case 
        when @n = 1 then
            'SOMETEXT'
    else
        case 
            when @m = 1 then
                'SOMEOTHERTEXT'
            when @m = 2 then
                'SOMEOTHERTEXTGOESHERE'
        end
    end as col1
-- n=1 => returns SOMETEXT regardless of @m
-- n=2 and m=1 => returns SOMEOTHERTEXT
-- n=2 and m=2 => returns SOMEOTHERTEXTGOESHERE
-- n=2 and m>2 => returns null (no else defined for inner case)

Changing plot scale by a factor in matplotlib

To set the range of the x-axis, you can use set_xlim(left, right), here are the docs

Update:

It looks like you want an identical plot, but only change the 'tick values', you can do that by getting the tick values and then just changing them to whatever you want. So for your need it would be like this:

ticks = your_plot.get_xticks()*10**9
your_plot.set_xticklabels(ticks)

How to Select Columns in Editors (Atom,Notepad++, Kate, VIM, Sublime, Textpad,etc) and IDEs (NetBeans, IntelliJ IDEA, Eclipse, Visual Studio, etc)

jEdit:

With the keyboard: press Alt-\ (Opt-\ in Mac OS X) to toggle between rectangular and normal selection mode; then use Shift plus arrow keys to extend selection. You can switch back to regular selection mode with another Alt-\ (Opt-\ in Mac OS X), if desired.

With the mouse: Either use Alt-\ (Opt-\ in Mac OS X) as above to toggle rectangular selection mode, then drag as usual; or Ctrl-drag (Cmd-drag in Mac OS X). You can switch back to regular selection mode with another Alt-\ (Opt-\ in Mac OS X), if desired.

Actually, you can even make a non-rectangular selection the normal way and then hit Alt-\ (Opt-\ in Mac OS X) to convert it into a rectangular one.

How to have Ellipsis effect on Text

To Achieve ellipses for the text use the Text property numberofLines={1} which will automatically truncate the text with an ellipsis you can specify the ellipsizeMode as "head", "middle", "tail" or "clip" By default it is tail

https://reactnative.dev/docs/text#ellipsizemode

How to check whether mod_rewrite is enable on server?

I know this question is old but if you can edit your Apache configuration file to AllowOverride All from AllowOverride None

<Directory "${SRVROOT}/htdocs">
    #
    # Possible values for the Options directive are "None", "All",
    # or any combination of:
    #   Indexes Includes FollowSymLinks SymLinksifOwnerMatch ExecCGI MultiViews
    #
    # Note that "MultiViews" must be named *explicitly* --- "Options All"
    # doesn't give it to you.
    #
    # The Options directive is both complicated and important.  Please see
    # http://httpd.apache.org/docs/2.4/mod/core.html#options
    # for more information.
    #
    Options Indexes FollowSymLinks

    #
    # AllowOverride controls what directives may be placed in .htaccess files.
    # It can be "All", "None", or any combination of the keywords:
    #   AllowOverride FileInfo AuthConfig Limit
    #
    AllowOverride All

    #
    # Controls who can get stuff from this server.
    #
    Require all granted
</Directory>

How to convert a full date to a short date in javascript?

I wanted the date to be shown in the type='time' field.

The normal conversion skips the zeros and the form field does not show the value and puts forth an error in the console saying the format needs to be yyyy-mm-dd.

Hence I added a small statement (check)?(true):(false) as follows:

makeShortDate=(date)=>{
yy=date.getFullYear()
mm=date.getMonth()
dd=date.getDate()
shortDate=`${yy}-${(mm<10)?0:''}${mm+1}-${(dd<10)?0:''}${dd}`;
return shortDate;
}

Editor does not contain a main type

Try 'Update Project'. Once I did this, The Run as Java Application option appeared.

Fastest way to remove first char in a String

I'd guess that Remove and Substring would tie for first place, since they both slurp up a fixed-size portion of the string, whereas TrimStart does a scan from the left with a test on each character and then has to perform exactly the same work as the other two methods. Seriously, though, this is splitting hairs.

How to select a dropdown value in Selenium WebDriver using Java

I have not tried in Selenium, but for Galen test this is working,

var list = driver.findElementByID("periodID"); // this will return web element

list.click(); // this will open the dropdown list.

list.typeText("14w"); // this will select option "14w".

You can try this in selenium, the galen and selenium working are similar.

Setting focus on an HTML input box on page load

This line:

<input type="password" name="PasswordInput"/>

should have an id attribute, like so:

<input type="password" name="PasswordInput" id="PasswordInput"/>

How much does it cost to develop an iPhone application?

The rates that were quoted above are what you would expect to pay US developers; however, I do know some people who have been able to get their apps built for as little as $4,000 by using offshore developers.

Here is a blog post from a group that did this: http://www.lolerapps.com/why-outsourcing-iphone-apps-was-a-no-brainer-for-us

Also, Carla White wrote a fantastic eBook about the process she used to outsource her app called "Inside Secrets to an iPhone App". She talks about how she got a great deal because she was willing to work with a team that was still learning iPhone app development.

So, there are alternatives to the higher price developers discussed above.

How do I use MySQL through XAMPP?

Changing XAMPP Default Port: If you want to get XAMPP up and running, you should consider changing the port from the default 80 to say 7777.

  • In the XAMPP Control Panel, click on the Apache – Config button which is located next to the ‘Logs’ button.

  • Select ‘Apache (httpd.conf)’ from the drop down. (Notepad should open)

  • Do Ctrl+F to find ’80’ and change line Listen 80 to Listen 7777

  • Find again and change line ServerName localhost:80 to ServerName localhost:7777

  • Save and re-start Apache. It should be running by now.

The only demerit to this technique is, you have to explicitly include the port number in the localhost url. Rather than http://localhost it becomes http://localhost:7777.

Fastest way to set all values of an array?

As another option and for posterity I was looking into this recently and found a solution that allows a much shorter loop by handing some of the work off to the System class, which (if the JVM you're using is smart enough) can be turned into a memset operation:-

/*
 * initialize a smaller piece of the array and use the System.arraycopy 
 * call to fill in the rest of the array in an expanding binary fashion
 */
public static void bytefill(byte[] array, byte value) {
  int len = array.length;

  if (len > 0){
    array[0] = value;
  }

  //Value of i will be [1, 2, 4, 8, 16, 32, ..., len]
  for (int i = 1; i < len; i += i) {
    System.arraycopy(array, 0, array, i, ((len - i) < i) ? (len - i) : i);
  }
}

This solution was taken from the IBM research paper "Java server performance: A case study of building efficient, scalable Jvms" by R. Dimpsey, R. Arora, K. Kuiper.

Simplified explanation

As the comment suggests, this sets index 0 of the destination array to your value then uses the System class to copy one object i.e. the object at index 0 to index 1 then those two objects (index 0 and 1) into 2 and 3, then those four objects (0,1,2 and 3) into 4,5,6 and 7 and so on...

Efficiency (at the point of writing)

In a quick run through, grabbing the System.nanoTime() before and after and calculating a duration I came up with:-

  • This method : 332,617 - 390,262 ('highest - lowest' from 10 tests)
  • Float[] n = new Float[array.length]; //Fill with null : 666,650
  • Setting via loop : 3,743,488 - 9,767,744 ('highest - lowest' from 10 tests)
  • Arrays.fill : 12,539,336

The JVM and JIT compilation

It should be noted that as the JVM and JIT evolves, this approach may well become obsolete as library and runtime optimisations could reach or even exceed these numbers simply using fill(). At the time of writing, this was the fastest option I had found. It has been mentioned this might not be the case now but I have not checked. This is the beauty and the curse of Java.

How to give a pandas/matplotlib bar graph custom colors

I found the easiest way is to use the colormap parameter in .plot() with one of the preset color gradients:

df.plot(kind='bar', stacked=True, colormap='Paired')

enter image description here

You can find a large list of preset colormaps here.

colormaps

VBA Go to last empty row

If you are certain that you only need column A, then you can use an End function in VBA to get that result.

If all the cells A1:A100 are filled, then to select the next empty cell use:

Range("A1").End(xlDown).Offset(1, 0).Select

Here, End(xlDown) is the equivalent of selecting A1 and pressing Ctrl + Down Arrow.

If there are blank cells in A1:A100, then you need to start at the bottom and work your way up. You can do this by combining the use of Rows.Count and End(xlUp), like so:

Cells(Rows.Count, 1).End(xlUp).Offset(1, 0).Select

Going on even further, this can be generalized to selecting a range of cells, starting at a point of your choice (not just in column A). In the following code, assume you have values in cells C10:C100, with blank cells interspersed in between. You wish to select all the cells C10:C100, not knowing that the column ends at row 100, starting by manually selecting C10.

Range(Selection, Cells(Rows.Count, Selection.Column).End(xlUp)).Select

The above line is perhaps one of the more important lines to know as a VBA programmer, as it allows you to dynamically select ranges based on very few criteria, and not be bothered with blank cells in the middle.

What's the best way to validate an XML file against an XSD file?

Using Woodstox, configure the StAX parser to validate against your schema and parse the XML.

If exceptions are caught the XML is not valid, otherwise it is valid:

// create the XSD schema from your schema file
XMLValidationSchemaFactory schemaFactory = XMLValidationSchemaFactory.newInstance(XMLValidationSchema.SCHEMA_ID_W3C_SCHEMA);
XMLValidationSchema validationSchema = schemaFactory.createSchema(schemaInputStream);

// create the XML reader for your XML file
WstxInputFactory inputFactory = new WstxInputFactory();
XMLStreamReader2 xmlReader = (XMLStreamReader2) inputFactory.createXMLStreamReader(xmlInputStream);

try {
    // configure the reader to validate against the schema
    xmlReader.validateAgainst(validationSchema);

    // parse the XML
    while (xmlReader.hasNext()) {
        xmlReader.next();
    }

    // no exceptions, the XML is valid

} catch (XMLStreamException e) {

    // exceptions, the XML is not valid

} finally {
    xmlReader.close();
}

Note: If you need to validate multiple files, you should try to reuse your XMLInputFactory and XMLValidationSchema in order to maximize the performance.

Something better than .NET Reflector?

The latest version from Red Gate is 6.1. However the 5.1 version cannot automatically update to version 6 because there were changes to the Terms of Service, so instead you are redirected to the site to download the 6.1 version. This is mostly because of legal reasons as you can check in the following post:

Oi! What's going on with the .NET Reflector update mechanism?

After you manually update to 6.1 you will no longer experience any problems.

How to find reason of failed Build without any error or warning

On my side, i got this problem when i added a new project (Library)

How i solved it

Right click the new added Library go to Properties then Application, under Application change the Target Framework to the framework of all projects.

The problem is that you have project using different target frameworks.

Running CMake on Windows

The default generator for Windows seems to be set to NMAKE. Try to use:

cmake -G "MinGW Makefiles"

Or use the GUI, and select MinGW Makefiles when prompted for a generator. Don't forget to cleanup the directory where you tried to run CMake, or delete the cache in the GUI. Otherwise, it will try again with NMAKE.

Change x axes scale in matplotlib

Try using matplotlib.pyplot.ticklabel_format:

import matplotlib.pyplot as plt
...
plt.ticklabel_format(style='sci', axis='x', scilimits=(0,0))

This applies scientific notation (i.e. a x 10^b) to your x-axis tickmarks

Android: How to detect double-tap?

To detect the type of gesture tap one can implement something inline with this: ( here projectText is an EditText )

    projectText.setOnTouchListener(new View.OnTouchListener() {
        private GestureDetector gestureDetector = new GestureDetector(activity, new GestureDetector.SimpleOnGestureListener() {
            @Override
            public boolean onDoubleTap(MotionEvent e) {
                projectText.setInputType(InputType.TYPE_CLASS_TEXT);
                activity.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE);
                return super.onDoubleTap(e);
            }
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                    projectText.setInputType(InputType.TYPE_NULL); // disable soft input
                    final int itemPosition = getLayoutPosition();
                    if(!projects.get(itemPosition).getProjectId().equals("-1"))
                        listener.selectedClick(projects.get(itemPosition));

                return super.onSingleTapUp(e);
            }

        });

        @Override
        public boolean onTouch(View v, MotionEvent event) {
            gestureDetector.onTouchEvent(event);
            return false; //true stops propagation of the event
        }

    });

Node.js: get path from the request

You can use this in app.js file .

var apiurl = express.Router();
apiurl.use(function(req, res, next) {
    var fullUrl = req.protocol + '://' + req.get('host') + req.originalUrl;
    next();
});
app.use('/', apiurl);

Facebook API - How do I get a Facebook user's profile image through the Facebook API (without requiring the user to "Allow" the application)

UPDATE:

Starting end August 2012, the API has been updated to allow you to retrieve user's profile pictures in varying sizes. Add the optional width and height fields as URL parameters:

https://graph.facebook.com/USER_ID/picture?width=WIDTH&height=HEIGHT

where WIDTH and HEIGHT are your requested dimension values.

This will return a profile picture with a minimum size of WIDTH x HEIGHT while trying to preserve the aspect ratio. For example,

https://graph.facebook.com/redbull/picture?width=140&height=110

returns

    {
      "data": {
        "url": "https://fbcdn-profile-a.akamaihd.net/hprofile-ak-ash4/c0.19.180.142/s148x148/2624_134501175351_4831452_a.jpg",
        "width": 148,
        "height": 117,
        "is_silhouette": false
      }
   }

END UPDATE

To get a user's profile picture, call

https://graph.facebook.com/USER_ID/picture

where USER_ID can be the user id number or the user name.

To get a user profile picture of a specific size, call

https://graph.facebook.com/USER_ID/picture?type=SIZE

where SIZE should be replaced with one of the words

square
small
normal
large

depending on the size you want.

This call will return a URL to a single image with its size based on your chosen type parameter.

For example:

https://graph.facebook.com/USER_ID/picture?type=small

returns a URL to a small version of the image.

The API only specifies the maximum size for profile images, not the actual size.

Square:

maximum width and height of 50 pixels.

Small

maximum width of 50 pixels and a maximum height of 150 pixels.

Normal

maximum width of 100 pixels and a maximum height of 300 pixels.

Large

maximum width of 200 pixels and a maximum height of 600 pixels.

If you call the default USER_ID/picture you get the square type.

CLARIFICATION

If you call (as per above example)

https://graph.facebook.com/redbull/picture?width=140&height=110

it will return a JSON response if you're using one of the Facebook SDKs request methods. Otherwise it will return the image itself. To always retrieve the JSON, add:

&redirect=false

like so:

https://graph.facebook.com/redbull/picture?width=140&height=110&redirect=false

IIS - 401.3 - Unauthorized

Here is what worked for me.

  1. Set the app pool identity to an account that can be assigned permissions to a folder.
  2. Ensure the source directory and all related files have been granted read rights to the files to the account assigned to the app pool identity property
  3. In IIS, at the server root node, set anonymous user to inherit from app pool identity. (This was the part I struggled with)

To set the server anonymous to inherit from the app pool identity do the following..

  • Open IIS Manager (inetmgr)
  • In the left-hand pane select the root node (server host name)
  • In the middle pane open the 'Authentication' applet
  • Highlight 'Anonymous Authentication'
  • In the right-hand pane select 'Edit...' (a dialog box should open)
  • select 'Application pool identity'

Maximum and minimum values in a textbox

https://jsfiddle.net/co1z0qg0/141/

<input type="text">
<script>
$('input').on('keyup', function() {
    var val = parseInt($(this).val()),
        max = 100;

    val = isNaN(val) ? 0 : Math.max(Math.min(val, max), 0);
    $(this).val(val);
});
</script>

or better

https://jsfiddle.net/co1z0qg0/142/

<input type="number" max="100">
<script>
$(function() {
    $('input[type="number"]').on('keyup', function() {
        var el = $(this),
            val = Math.max((0, el.val())),
            max = parseInt(el.attr('max'));

        el.val(isNaN(max) ? val : Math.min(max, val));
  });
});
</script>
<style>
input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
input[type="number"] {
    -moz-appearance: textfield;
}
</style>

Writing outputs to log file and console

Try this, it will do the work:

log_file=$curr_dir/log_file.txt
exec > >(tee -a ${log_file} )
exec 2> >(tee -a ${log_file} >&2)

Array of arrays (Python/NumPy)

It seems strange that you would write arrays without commas (is that a MATLAB syntax?)

Have you tried going through NumPy's documentation on multi-dimensional arrays?

It seems NumPy has a "Python-like" append method to add items to a NumPy n-dimensional array:

>>> p = np.array([[1,2],[3,4]])

>>> p = np.append(p, [[5,6]], 0)

>>> p = np.append(p, [[7],[8],[9]],1)

>>> p
array([[1, 2, 7], [3, 4, 8], [5, 6, 9]])

It has also been answered already...

From the documentation for MATLAB users:

You could use a matrix constructor which takes a string in the form of a matrix MATLAB literal:

mat("1 2 3; 4 5 6")

or

matrix("[1 2 3; 4 5 6]")

Please give it a try and tell me how it goes.

How can I recover the return value of a function passed to multiprocessing.Process?

The pebble package has a nice abstraction leveraging multiprocessing.Pipe which makes this quite straightforward:

from pebble import concurrent

@concurrent.process
def function(arg, kwarg=0):
    return arg + kwarg

future = function(1, kwarg=1)

print(future.result())

Example from: https://pythonhosted.org/Pebble/#concurrent-decorators

Difference between exit() and sys.exit() in Python

If I use exit() in a code and run it in the shell, it shows a message asking whether I want to kill the program or not. It's really disturbing. See here

But sys.exit() is better in this case. It closes the program and doesn't create any dialogue box.

Why use double indirection? or Why use pointers to pointers?

Why double pointers?

The objective is to change what studentA points to, using a function.

#include <stdio.h>
#include <stdlib.h>


typedef struct Person{
    char * name;
} Person; 

/**
 * we need a ponter to a pointer, example: &studentA
 */
void change(Person ** x, Person * y){
    *x = y; // since x is a pointer to a pointer, we access its value: a pointer to a Person struct.
}

void dontChange(Person * x, Person * y){
    x = y;
}

int main()
{

    Person * studentA = (Person *)malloc(sizeof(Person));
    studentA->name = "brian";

    Person * studentB = (Person *)malloc(sizeof(Person));
    studentB->name = "erich";

    /**
     * we could have done the job as simple as this!
     * but we need more work if we want to use a function to do the job!
     */
    // studentA = studentB;

    printf("1. studentA = %s (not changed)\n", studentA->name);

    dontChange(studentA, studentB);
    printf("2. studentA = %s (not changed)\n", studentA->name);

    change(&studentA, studentB);
    printf("3. studentA = %s (changed!)\n", studentA->name);

    return 0;
}

/**
 * OUTPUT:
 * 1. studentA = brian (not changed)
 * 2. studentA = brian (not changed)
 * 3. studentA = erich (changed!)
 */

Convert List into Comma-Separated String

Try

Console.WriteLine((string.Join(",", lst.Select(x=>x.ToString()).ToArray())));

HTH

Empty brackets '[]' appearing when using .where

You can use the lower function:

Guide.where("lower(title)='attack'") 

As a comment: Work on your question. The title isn't terribly informative, and you drop a big chunk of code at the end that is irrelevant to your question.

Insert line after first match using sed

A POSIX compliant one using the s command:

sed '/CLIENTSCRIPT="foo"/s/.*/&\
CLIENTSCRIPT2="hello"/' file

Lotus Notes email as an attachment to another email

Answer from Chris is not possible because there is no save mail option (at least in version 8.5) in LN

It is possible, File > Save As

Change Timezone in Lumen or Laravel 5

After changing app.php, make sure you run:

 php artisan config:clear

This is needed to clear the cache of config settings. If you notice that your timestamps are still wrong after changing the timezone in your app.php file, then running the above command should refresh everything, and your new timezone should be effective.

System.Net.WebException: The remote name could not be resolved:

It's probably caused by a local network connectivity issue (but also a DNS error is possible). Unfortunately HResult is generic, however you can determine the exact issue catching HttpRequestException and then inspecting InnerException: if it's a WebException then you can check the WebException.Status property, for example WebExceptionStatus.NameResolutionFailure should indicate a DNS resolution problem.


It may happen, there isn't much you can do.

What I'd suggest to always wrap that (network related) code in a loop with a try/catch block (as also suggested here for other fallible operations). Handle known exceptions, wait a little (say 1000 msec) and try again (for say 3 times). Only if failed all times then you can quit/report an error to your users. Very raw example like this:

private const int NumberOfRetries = 3;
private const int DelayOnRetry = 1000;

public static async Task<HttpResponseMessage> GetFromUrlAsync(string url) {
    using (var client = new HttpClient()) {
        for (int i=1; i <= NumberOfRetries; ++i) {
            try {
                return await client.GetAsync(url); 
            }
            catch (Exception e) when (i < NumberOfRetries) {
                await Task.Delay(DelayOnRetry);
            }
        }
    }
}

ES6 exporting/importing in index file

Also, bear in mind that if you need to export multiple functions at once, like actions you can use

export * from './XThingActions';

Reset git proxy to default configuration

You can remove that configuration with:

git config --global --unset core.gitproxy

Make xargs handle filenames that contain spaces

Try

find . -name \*.mp3 -print0 | xargs -0 mplayer

instead of

ls | grep mp3 

how to check and set max_allowed_packet mysql variable

goto cpanel and login as Main Admin or Super Administrator

  1. find SSH/Shell Access ( you will find under the security tab of cpanel )

  2. now give the username and password of Super Administrator as root or whatyougave

    note: do not give any username, cos, it needs permissions
    
  3. once your into console type

    type ' mysql ' and press enter now you find youself in

    mysql> /* and type here like */

    mysql> set global net_buffer_length=1000000;

    Query OK, 0 rows affected (0.00 sec)

    mysql> set global max_allowed_packet=1000000000;

    Query OK, 0 rows affected (0.00 sec)

Now upload and enjoy!!!

How do I get the absolute directory of a file in bash?

To get the full path use:

readlink -f relative/path/to/file

To get the directory of a file:

dirname relative/path/to/file

You can also combine the two:

dirname $(readlink -f relative/path/to/file)

If readlink -f is not available on your system you can use this*:

function myreadlink() {
  (
  cd "$(dirname $1)"         # or  cd "${1%/*}"
  echo "$PWD/$(basename $1)" # or  echo "$PWD/${1##*/}"
  )
}

Note that if you only need to move to a directory of a file specified as a relative path, you don't need to know the absolute path, a relative path is perfectly legal, so just use:

cd $(dirname relative/path/to/file)

if you wish to go back (while the script is running) to the original path, use pushd instead of cd, and popd when you are done.


* While myreadlink above is good enough in the context of this question, it has some limitation relative to the readlink tool suggested above. For example it doesn't correctly follow a link to a file with different basename.

Javascript Append Child AFTER Element

You can use:

if (parentGuest.nextSibling) {
  parentGuest.parentNode.insertBefore(childGuest, parentGuest.nextSibling);
}
else {
  parentGuest.parentNode.appendChild(childGuest);
}

But as Pavel pointed out, the referenceElement can be null/undefined, and if so, insertBefore behaves just like appendChild. So the following is equivalent to the above:

parentGuest.parentNode.insertBefore(childGuest, parentGuest.nextSibling);

javascript regex for special characters

var regex = /^[a-zA-Z0-9!@#\$%\^\&*\)\(+=._-]+$/g

Should work

Also may want to have a minimum length i.e. 6 characters

var regex = /^[a-zA-Z0-9!@#\$%\^\&*\)\(+=._-]{6,}$/g

sudo: port: command not found

You can quite simply add the line:

source ~/.profile

To the bottom of your shell rc file - if you are using bash then it would be your ~/.bash_profile if you are using zsh it would be your ~/.zshrc

Then open a new Terminal window and type ports -v you should see output that looks like the following:

~ [ port -v                                                                                                              ] 12:12 pm
MacPorts 2.1.3
Entering interactive mode... ("help" for help, "quit" to quit)
[Users/sh] > quit
Goodbye

Hope that helps.

What does the 'u' symbol mean in front of string values?

The 'u' in front of the string values means the string is a Unicode string. Unicode is a way to represent more characters than normal ASCII can manage. The fact that you're seeing the u means you're on Python 2 - strings are Unicode by default on Python 3, but on Python 2, the u in front distinguishes Unicode strings. The rest of this answer will focus on Python 2.

You can create a Unicode string multiple ways:

>>> u'foo'
u'foo'
>>> unicode('foo') # Python 2 only
u'foo'

But the real reason is to represent something like this (translation here):

>>> val = u'???????????? ? ?????????????'
>>> val
u'\u041e\u0437\u043d\u0430\u043a\u043e\u043c\u044c\u0442\u0435\u0441\u044c \u0441 \u0434\u043e\u043a\u0443\u043c\u0435\u043d\u0442\u0430\u0446\u0438\u0435\u0439'
>>> print val
???????????? ? ?????????????

For the most part, Unicode and non-Unicode strings are interoperable on Python 2.

There are other symbols you will see, such as the "raw" symbol r for telling a string not to interpret backslashes. This is extremely useful for writing regular expressions.

>>> 'foo\"'
'foo"'
>>> r'foo\"'
'foo\\"'

Unicode and non-Unicode strings can be equal on Python 2:

>>> bird1 = unicode('unladen swallow')
>>> bird2 = 'unladen swallow'
>>> bird1 == bird2
True

but not on Python 3:

>>> x = u'asdf' # Python 3
>>> y = b'asdf' # b indicates bytestring
>>> x == y
False