Programs & Examples On #Ntpd

How to make sure docker's time syncs with that of the host?

Enabling Hyper-V in Windows Features solved the problem: Windows Features

Removing duplicates in the lists

To make a new list retaining the order of first elements of duplicates in L

newlist=[ii for n,ii in enumerate(L) if ii not in L[:n]]

for example if L=[1, 2, 2, 3, 4, 2, 4, 3, 5] then newlist will be [1,2,3,4,5]

This checks each new element has not appeared previously in the list before adding it. Also it does not need imports.

How to Call Controller Actions using JQuery in ASP.NET MVC

We can call Controller method using Javascript / Jquery very easily as follows:

Suppose following is the Controller method to be called returning an array of some class objects. Let the class is 'A'

public JsonResult SubMenu_Click(string param1, string param2)

       A[] arr = null;
           Get Result and fill arr.

        catch { }

        return Json(arr , JsonRequestBehavior.AllowGet);


Following is the complex type (class)

 public class A

  public string property1 {get ; set ;}

  public string property2 {get ; set ;}


Now it was turn to call above controller method by JQUERY. Following is the Jquery function to call the controller method.

function callControllerMethod(value1 , value2) {
    var strMethodUrl = '@Url.Action("SubMenu_Click", "Home")?param1=value1 &param2=value2'
    $.getJSON(strMethodUrl, receieveResponse);

function receieveResponse(response) {

    if (response != null) {
        for (var i = 0; i < response.length; i++) {

In the above Jquery function 'callControllerMethod' we develop controller method url and put that in a variable named 'strMehodUrl' and call getJSON method of Jquery API.

receieveResponse is the callback function receiving the response or return value of the controllers method.

Here we made use of JSON , since we can't make use of the C# class object

directly into the javascript function , so we converted the result (arr) in controller method into JSON object as follows:

Json(arr , JsonRequestBehavior.AllowGet);

and returned that Json object.

Now in callback function of the Javascript / JQuery we can make use of this resultant JSON object and work accordingly to show response data on UI.

For more detaill click here

How do I handle newlines in JSON?

well, it is not really necessary to create a function for this when it can be done simply with 1 CSS class.

just wrap your text around this class and see the magic :D

 <p style={{whiteSpace: 'pre-line'}}>my json text goes here \n\n</p>

note: because you will always present your text in frontend with HTML you can add the style={{whiteSpace: 'pre-line'}} to any tag, not just the p tag.

How do I disable log messages from the Requests library?

import logging
urllib3_logger = logging.getLogger('urllib3')

In this way all the messages of level=INFO from urllib3 won't be present in the logfile.

So you can continue to use the level=INFO for your log messages...just modify this for the library you are using.

jQuery xml error ' No 'Access-Control-Allow-Origin' header is present on the requested resource.'

You won't be able to make an ajax call to from a file deployed at due to the same-origin policy.

As the source (aka origin) page and the target URL are at different domains ( and, your code is actually attempting to make a Cross-domain (CORS) request, not an ordinary GET.

In a few words, the same-origin policy says that browsers should only allow ajax calls to services at the same domain of the HTML page.


A page at can only directly request services that are at, like If the service is hosted at another domain (say, the browser won't make the call directly (as you'd expect). Instead, it will try to make a CORS request.

To put it shortly, to perform a (CORS) request* across different domains, your browser:

  • Will include an Origin header in the original request (with the page's domain as value) and perform it as usual; and then
  • Only if the server response to that request contains the adequate headers (Access-Control-Allow-Origin is one of them) allowing the CORS request, the browse will complete the call (almost** exactly the way it would if the HTML page was at the same domain).
    • If the expected headers don't come, the browser simply gives up (like it did to you).

* The above depicts the steps in a simple request, such as a regular GET with no fancy headers. If the request is not simple (like a POST with application/json as content type), the browser will hold it a moment, and, before fulfilling it, will first send an OPTIONS request to the target URL. Like above, it only will continue if the response to this OPTIONS request contains the CORS headers. This OPTIONS call is known as preflight request.
** I'm saying almost because there are other differences between regular calls and CORS calls. An important one is that some headers, even if present in the response, will not be picked up by the browser if they aren't included in the Access-Control-Expose-Headers header.

How to fix it?

Was it just a typo? Sometimes the JavaScript code has just a typo in the target domain. Have you checked? If the page is at it will only make regular calls to! Other URLs, such as or even or are considered different domains by the browser! Yes, if the port is different, then it is a different domain!

Add the headers. The simplest way to enable CORS is by adding the necessary headers (as Access-Control-Allow-Origin) to the server's responses. (Each server/language has a way to do that - check some solutions here.)

Last resort: If you don't have server-side access to the service, you can also mirror it (through tools such as reverse proxies), and include all the necessary headers there.

How can I change the image of an ImageView?

if (android.os.Build.VERSION.SDK_INT >= 21) {
            storeViewHolder.storeNameTextView.setImageDrawable(context.getResources().getDrawable(array[position], context.getTheme()));
} else {

Disable and enable buttons in C#

button2.Enabled == true ;

should be

button2.Enabled = true ;

How to declare and initialize a static const array as a class member?

You are mixing pointers and arrays. If what you want is an array, then use an array:

struct test {
   static int data[10];        // array, not pointer!
int test::data[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

If on the other hand you want a pointer, the simplest solution is to write a helper function in the translation unit that defines the member:

struct test {
   static int *data;
// cpp
static int* generate_data() {            // static here is "internal linkage"
   int * p = new int[10];
   for ( int i = 0; i < 10; ++i ) p[i] = 10*i;
   return p;
int *test::data = generate_data();

How to find the array index with a value?

When the lists aren't extremely long, this is the best way I know:

function getIndex(val) {
    for (var i = 0; i < imageList.length; i++) {
        if (imageList[i] === val) {
            return i;

var imageList = [100, 200, 300, 400, 500];
var index = getIndex(200);

Using variables inside a bash heredoc

In answer to your first question, there's no parameter substitution because you've put the delimiter in quotes - the bash manual says:

The format of here-documents is:


No parameter expansion, command substitution, arithmetic expansion, or pathname expansion is performed on word. If any characters in word are quoted, the delimiter is the result of quote removal on word, and the lines in the here-document are not expanded. If word is unquoted, all lines of the here-document are subjected to parameter expansion, command substitution, and arithmetic expansion. [...]

If you change your first example to use <<EOF instead of << "EOF" you'll find that it works.

In your second example, the shell invokes sudo only with the parameter cat, and the redirection applies to the output of sudo cat as the original user. It'll work if you try:

sudo sh -c "cat > /path/to/outfile" <<EOT
my text...

DateTime vs DateTimeOffset

There's a few places where DateTimeOffset makes sense. One is when you're dealing with recurring events and daylight savings time. Let's say I want to set an alarm to go off at 9am every day. If I use the "store as UTC, display as local time" rule, then the alarm will be going off at a different time when daylight savings time is in effect.

There are probably others, but the above example is actually one that I've run into in the past (this was before the addition of DateTimeOffset to the BCL - my solution at the time was to explicitly store the time in the local timezone, and save the timezone information along side it: basically what DateTimeOffset does internally).

What is JavaScript's highest integer value that a number can go to without losing precision?

Jimmy's answer correctly represents the continuous JavaScript integer spectrum as -9007199254740992 to 9007199254740992 inclusive (sorry 9007199254740993, you might think you are 9007199254740993, but you are wrong! Demonstration below or in jsfiddle).


However, there is no answer that finds/proves this programatically (other than the one CoolAJ86 alluded to in his answer that would finish in 28.56 years ;), so here's a slightly more efficient way to do that (to be precise, it's more efficient by about 28.559999999968312 years :), along with a test fiddle:

 * Checks if adding/subtracting one to/from a number yields the correct result._x000D_
 * @param number The number to test_x000D_
 * @return true if you can add/subtract 1, false otherwise._x000D_
var canAddSubtractOneFromNumber = function(number) {_x000D_
    var numMinusOne = number - 1;_x000D_
    var numPlusOne = number + 1;_x000D_
    return ((number - numMinusOne) === 1) && ((number - numPlusOne) === -1);_x000D_
//Find the highest number_x000D_
var highestNumber = 3; //Start with an integer 1 or higher_x000D_
//Get a number higher than the valid integer range_x000D_
while (canAddSubtractOneFromNumber(highestNumber)) {_x000D_
    highestNumber *= 2;_x000D_
//Find the lowest number you can't add/subtract 1 from_x000D_
var numToSubtract = highestNumber / 4;_x000D_
while (numToSubtract >= 1) {_x000D_
    while (!canAddSubtractOneFromNumber(highestNumber - numToSubtract)) {_x000D_
        highestNumber = highestNumber - numToSubtract;_x000D_
    numToSubtract /= 2;_x000D_
}        _x000D_
//And there was much rejoicing.  Yay.    _x000D_
console.log('HighestNumber = ' + highestNumber);

How to determine previous page URL in Angular?

Angular 6 updated code for getting previous url as string.

import { Router, RoutesRecognized } from '@angular/router';
import { filter, pairwise } from 'rxjs/operators';

export class AppComponent implements OnInit {

    constructor (
        public router: Router
    ) {

    ngOnInit() {
            .pipe(filter((e: any) => e instanceof RoutesRecognized),
            ).subscribe((e: any) => {
                console.log(e[0].urlAfterRedirects); // previous url

How to get value by class name in JavaScript or jquery?

Try this:

    var yourArray = [];


Creating and appending text to txt file in VB.NET

Why not just use the following simple call (with any exception handling added)?

File.AppendAllText(strFile, "Start Error Log for today")

This should answer the question fully!

If File.Exists(strFile)
  File.AppendAllText(strFile, String.Format("Error Message in  Occured at-- {0:dd-MMM-yyyy}{1}", Date.Today, Environment.NewLine))
  File.AppendAllText(strFile, "Start Error Log for today{0}Error Message in  Occured at-- {1:dd-MMM-yyyy}{0}", Environment.NewLine, Date.Today)
End If

Where can I find the .apk file on my device, when I download any app and install?

You can do that I believe. It needs root permission. If you want to know where your apk files are stored, open a emulator and then go to

DDMS>File Explorer-> you can see a directory by name "data" -> Click on it and you will see a "app" folder.

Your apks are stored there. In fact just copying a apk directly to the folder works for me with emulators.

JSON Array iteration in Android/Java

You are using the same Cast object for every entry. On each iteration you just changed the same object instead creating a new one.

This code should fix it:

JSONArray jCastArr = jObj.getJSONArray("abridged_cast");
ArrayList<Cast> castList= new ArrayList<Cast>();

for (int i=0; i < jCastArr.length(); i++) {
    Cast person = new Cast();  // create a new object here
    JSONObject jpersonObj = jCastArr.getJSONObject(i);

    person.castId = (String) jpersonObj.getString("id");
    person.castFullName = (String) jpersonObj.getString("name");

details.castList = castList;

scp or sftp copy multiple files with single command

You can do this way:

scp hostname@serverNameOrServerIp:/path/to/files/\\{file1,file2,file3\\}.fileExtension ./

This will download all the listed filenames to whatever local directory you're on.

Make sure not to put spaces between each filename only use a comma ,.

How to get the Parent's parent directory in Powershell?

Split-Path -Path (Get-Location).Path -Parent

c++ bool question

false == 0 and true = !false

i.e. anything that is not zero and can be converted to a boolean is not false, thus it must be true.

Some examples to clarify:

if(0)          // false
if(1)          // true
if(2)          // true
if(0 == false) // true
if(0 == true)  // false
if(1 == false) // false
if(1 == true)  // true
if(2 == false) // false
if(2 == true)  // false
cout << false  // 0
cout << true   // 1

true evaluates to 1, but any int that is not false (i.e. 0) evaluates to true but is not equal to true since it isn't equal to 1.

How to efficiently change image attribute "src" from relative URL to absolute using jQuery?

The replace method in Javascript returns a value, and does not act upon the existing string object. See:

In your example, you will have to do

$(this).attr("src", $(this).attr("src").replace(...))

How to download videos from youtube on java?

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import java.util.logging.Formatter;
import java.util.logging.Handler;
import java.util.logging.Level;
import java.util.logging.LogRecord;
import java.util.logging.Logger;
import java.util.regex.Pattern;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.CookieStore;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.protocol.ClientContext;
import org.apache.http.client.utils.URIUtils;
import org.apache.http.client.utils.URLEncodedUtils;
import org.apache.http.impl.client.BasicCookieStore;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;

public class JavaYoutubeDownloader {

 public static String newline = System.getProperty("line.separator");
 private static final Logger log = Logger.getLogger(JavaYoutubeDownloader.class.getCanonicalName());
 private static final Level defaultLogLevelSelf = Level.FINER;
 private static final Level defaultLogLevel = Level.WARNING;
 private static final Logger rootlog = Logger.getLogger("");
 private static final String scheme = "http";
 private static final String host = "";
 private static final Pattern commaPattern = Pattern.compile(",");
 private static final Pattern pipePattern = Pattern.compile("\\|");
 private static final char[] ILLEGAL_FILENAME_CHARACTERS = { '/', '\n', '\r', '\t', '\0', '\f', '`', '?', '*', '\\', '<', '>', '|', '\"', ':' };

 private static void usage(String error) {
  if (error != null) {
   System.err.println("Error: " + error);
  System.err.println("usage: JavaYoutubeDownload VIDEO_ID DESTINATION_DIRECTORY");

 public static void main(String[] args) {
  if (args == null || args.length == 0) {
   usage("Missing video id. Extract from");
  try {

   String videoId = null;
   String outdir = ".";
   // TODO Ghetto command line parsing
   if (args.length == 1) {
    videoId = args[0];
   } else if (args.length == 2) {
    videoId = args[0];
    outdir = args[1];

   int format = 18; //
   String encoding = "UTF-8";
   String userAgent = "Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv: Gecko/20101203 Firefox/3.6.13";
   File outputDir = new File(outdir);
   String extension = getExtension(format);

   play(videoId, format, encoding, userAgent, outputDir, extension);

  } catch (Throwable t) {

 private static String getExtension(int format) {
  // TODO
  return "mp4";

 private static void play(String videoId, int format, String encoding, String userAgent, File outputdir, String extension) throws Throwable {
  log.fine("Retrieving " + videoId);
  List<NameValuePair> qparams = new ArrayList<NameValuePair>();
  qparams.add(new BasicNameValuePair("video_id", videoId));
  qparams.add(new BasicNameValuePair("fmt", "" + format));
  URI uri = getUri("get_video_info", qparams);

  CookieStore cookieStore = new BasicCookieStore();
  HttpContext localContext = new BasicHttpContext();
  localContext.setAttribute(ClientContext.COOKIE_STORE, cookieStore);

  HttpClient httpclient = new DefaultHttpClient();
  HttpGet httpget = new HttpGet(uri);
  httpget.setHeader("User-Agent", userAgent);

  log.finer("Executing " + uri);
  HttpResponse response = httpclient.execute(httpget, localContext);
  HttpEntity entity = response.getEntity();
  if (entity != null && response.getStatusLine().getStatusCode() == 200) {
   InputStream instream = entity.getContent();
   String videoInfo = getStringFromInputStream(encoding, instream);
   if (videoInfo != null && videoInfo.length() > 0) {
    List<NameValuePair> infoMap = new ArrayList<NameValuePair>();
    URLEncodedUtils.parse(infoMap, new Scanner(videoInfo), encoding);
    String token = null;
    String downloadUrl = null;
    String filename = videoId;

    for (NameValuePair pair : infoMap) {
     String key = pair.getName();
     String val = pair.getValue();
     log.finest(key + "=" + val);
     if (key.equals("token")) {
      token = val;
     } else if (key.equals("title")) {
      filename = val;
     } else if (key.equals("fmt_url_map")) {
      String[] formats = commaPattern.split(val);
      for (String fmt : formats) {
       String[] fmtPieces = pipePattern.split(fmt);
       if (fmtPieces.length == 2) {
        // in the end, download somethin!
        downloadUrl = fmtPieces[1];
        int pieceFormat = Integer.parseInt(fmtPieces[0]);
        if (pieceFormat == format) {
         // found what we want
         downloadUrl = fmtPieces[1];

    filename = cleanFilename(filename);
    if (filename.length() == 0) {
     filename = videoId;
    } else {
     filename += "_" + videoId;
    filename += "." + extension;
    File outputfile = new File(outputdir, filename);

    if (downloadUrl != null) {
     downloadWithHttpClient(userAgent, downloadUrl, outputfile);

 private static void downloadWithHttpClient(String userAgent, String downloadUrl, File outputfile) throws Throwable {
  HttpGet httpget2 = new HttpGet(downloadUrl);
  httpget2.setHeader("User-Agent", userAgent);

  log.finer("Executing " + httpget2.getURI());
  HttpClient httpclient2 = new DefaultHttpClient();
  HttpResponse response2 = httpclient2.execute(httpget2);
  HttpEntity entity2 = response2.getEntity();
  if (entity2 != null && response2.getStatusLine().getStatusCode() == 200) {
   long length = entity2.getContentLength();
   InputStream instream2 = entity2.getContent();
   log.finer("Writing " + length + " bytes to " + outputfile);
   if (outputfile.exists()) {
   FileOutputStream outstream = new FileOutputStream(outputfile);
   try {
    byte[] buffer = new byte[2048];
    int count = -1;
    while ((count = != -1) {
     outstream.write(buffer, 0, count);
   } finally {

 private static String cleanFilename(String filename) {
   filename = filename.replace(c, '_');
  return filename;

 private static URI getUri(String path, List<NameValuePair> qparams) throws URISyntaxException {
  URI uri = URIUtils.createURI(scheme, host, -1, "/" + path, URLEncodedUtils.format(qparams, "UTF-8"), null);
  return uri;

 private static void setupLogging() {
  changeFormatter(new Formatter() {
   public String format(LogRecord arg0) {
    return arg0.getMessage() + newline;

 private static void changeFormatter(Formatter formatter) {
  Handler[] handlers = rootlog.getHandlers();
  for (Handler handler : handlers) {

 private static void explicitlySetAllLogging(Level level) {
  for (Handler handler : rootlog.getHandlers()) {

 private static String getStringFromInputStream(String encoding, InputStream instream) throws UnsupportedEncodingException, IOException {
  Writer writer = new StringWriter();

  char[] buffer = new char[1024];
  try {
   Reader reader = new BufferedReader(new InputStreamReader(instream, encoding));
   int n;
   while ((n = != -1) {
    writer.write(buffer, 0, n);
  } finally {
  String result = writer.toString();
  return result;

 * <pre>
 * Exploded results from get_video_info:
 * fexp=90...
 * allow_embed=1
 * fmt_stream_map=35|http://v9.lscache8...
 * fmt_url_map=35|http://v9.lscache8...
 * allow_ratings=1
 * keywords=Stefan Molyneux,Luke Bessey,anarchy,stateless society,giant stone cow,the story of our unenslavement,market anarchy,voluntaryism,anarcho capitalism
 * track_embed=0
 * fmt_list=35/854x480/9/0/115,34/640x360/9/0/115,18/640x360/9/0/115,5/320x240/7/0/0
 * author=lukebessey
 * muted=0
 * length_seconds=390
 * plid=AA...
 * ftoken=null
 * status=ok
 * watermark=,
 * timestamp=12...
 * has_cc=False
 * fmt_map=35/854x480/9/0/115,34/640x360/9/0/115,18/640x360/9/0/115,5/320x240/7/0/0
 * leanback_module=
 * hl=en_US
 * endscreen_module=
 * vq=auto
 * avg_rating=5.0
 * video_id=S6IZP3yRJ9I
 * token=vPpcFNh...
 * thumbnail_url=
 * title=The Story of Our Unenslavement - Animated
 * </pre>

How to send an HTTP request using Telnet

To somewhat expand on earlier answers, there are a few complications.

telnet is not particularly scriptable; you might prefer to use nc (aka netcat) instead, which handles non-terminal input and signals better.

Also, unlike telnet, nc actually allows SSL (and so https instead of http traffic -- you need port 443 instead of port 80 then).

There is a difference between HTTP 1.0 and 1.1. The recent version of the protocol requires the Host: header to be included in the request on a separate line after the POST or GET line, and to be followed by an empty line to mark the end of the request headers.

The HTTP protocol requires carriage return / line feed line endings. Many servers are lenient about this, but some are not. You might want to use

printf "%\r\n" \
    "GET /questions HTTP/1.1" \
    "Host:" \
    "" |
nc --ssl 443

If you fall back to HTTP/1.0 you don't always need the Host: header, but many modern servers require the header anyway; if multiple sites are hosted on the same IP address, the server doesn't know from GET /foo HTTP/1.0 whether you mean or if those two sites are both hosted on the same server (in the absence of a Host: header, a HTTP 1.0 server might just default to a different site than the one you want, so you don't get the contents you wanted).

The HTTPS protocol is identical to HTTP in these details; the only real difference is in how the session is set up initially.

Execute and get the output of a shell command in node.js

You can use the util library that comes with nodejs to get a promise from the exec command and can use that output as you need. Use restructuring to store the stdout and stderr in variables.

const util = require('util');
const exec = util.promisify(require('child_process').exec);

async function lsExample() {
  const {
  } = await exec('ls');
  console.log('stdout:', stdout);
  console.error('stderr:', stderr);

What's the pythonic way to use getters and setters?

In [1]: class test(object):
    def __init__(self):
        self.pants = 'pants'
    def p(self):
        return self.pants
    def p(self, value):
        self.pants = value * 2
In [2]: t = test()
In [3]: t.p
Out[3]: 'pants'
In [4]: t.p = 10
In [5]: t.p
Out[5]: 20

jquery dialog save cancel button styling

As of jquery ui version 1.8.16 below is how I got it working.

  buttons: { 
      "Save": {  
          text: 'Save', 
          class: 'btn primary', 
          click: function () {
              // do stuff

gcloud command not found - while installing Google Cloud SDK

I had the same problem and it was because the ~/.bash_profile had invalid fi statements.

The fix:

  1. Execute command sudo nano ~/.bash_profile
  2. Removed closing fi statements (the ones missing an opening if)
  3. Save .bash_profile changes
  4. Execute command source ~/.bash_profile

Node.js Mongoose.js string to ObjectId function

Just see the below code snippet if you are implementing a REST API through express and mongoose. (Example for ADD)

exports.AddSomething = (req,res,next) =>{_x000D_
  const newSomething = new SomeEntity({_x000D_
 _id:new mongoose.Types.ObjectId(), //its very own ID_x000D_
  theForeignKey: mongoose.Types.ObjectId(req.body.theForeignKey)// if you want to pass an object ID_x000D_

Hope it Helps

What is meant with "const" at end of function declaration?

Bar is guaranteed not to change the object it is being invoked on. See the section about const correctness in the C++ FAQ, for example.

Running an executable in Mac Terminal

Unix will only run commands if they are available on the system path, as you can view by the $PATH variable

echo $PATH

Executables located in directories that are not on the path cannot be run unless you specify their full location. So in your case, assuming the executable is in the current directory you are working with, then you can execute it as such


Where my-exec is the name of your program.

ERROR 2013 (HY000): Lost connection to MySQL server at 'reading authorization packet', system error: 0

I solved this by stopping mysql several times.

$ mysql.server stop
Shutting down MySQL
.. ERROR! The server quit without updating PID file (/usr/local/var/mysql/
$ mysql.server stop
Shutting down MySQL
$ mysql.server stop
ERROR! MySQL server PID file could not be found! (note: this is good)
$ mysql.server start

All good from here. I suspect mysql had been started more than once.

Is there a way to do repetitive tasks at intervals?

If you do not care about tick shifting (depending on how long did it took previously on each execution) and you do not want to use channels, it's possible to use native range function.


package main

import "fmt"
import "time"

func main() {
    go heartBeat()
    time.Sleep(time.Second * 5)

func heartBeat() {
    for range time.Tick(time.Second * 1) {


Produce a random number in a range using C#

Something like:

var rnd = new Random(DateTime.Now.Millisecond);
int ticks = rnd.Next(0, 3000);

Listing information about all database files in SQL Server

just adding my 2 cents .

if specifically looking to find total free space only in Data files or only in Log files in all the databases, we can use "data_space_id" column. 1 is for data files and 0 for log files.


Create Table ##temp
    DatabaseName sysname,
    Name sysname,
    spacetype sysname,
    physical_name nvarchar(500),
    size decimal (18,2),
    FreeSpace decimal (18,2)
Exec sp_msforeachdb '
Use [?];

Insert Into ##temp (DatabaseName, Name,spacetype, physical_name, Size, FreeSpace)
    Select DB_NAME() AS [DatabaseName], Name,   ***data_space_id*** , physical_name,
    Cast(Cast(Round(cast(size as decimal) * 8.0/1024.0,2) as decimal(18,2))/1024 as nvarchar) SizeGB,
    Cast(Cast(Round(cast(size as decimal) * 8.0/1024.0,2)/1024 as decimal(18,2)) -
        Cast(FILEPROPERTY(name, ''SpaceUsed'') * 8.0/1024.0 as decimal(18,2))/1024 as nvarchar) As FreeSpaceGB
    From sys.database_files'

    , sum(##temp.FreeSpace) 
    ##temp.spacetype = 1  
group by 

drop table ##temp 

./configure : /bin/sh^M : bad interpreter

Use the dos2unix command in linux to convert the saved file. example :

dos2unix file_name

Check if argparse optional argument is set or not

Very simple, after defining args variable by 'args = parser.parse_args()' it contains all data of args subset variables too. To check if a variable is set or no assuming the 'action="store_true" is used...

if args.argument_name:
   # do something
   # do something else

Why doesn't wireshark detect my interface?

Just uninstall NPCAP and install wpcap. This will fix the issue.

How to write a file with C in Linux?

First of all, the code you wrote isn't portable, even if you get it to work. Why use OS-specific functions when there is a perfectly platform-independent way of doing it? Here's a version that uses just a single header file and is portable to any platform that implements the C standard library.

#include <stdio.h>

int main(int argc, char **argv)
    FILE* sourceFile;
    FILE* destFile;
    char buf[50];
    int numBytes;

        printf("Usage: fcopy source destination\n");
        return 1;

    sourceFile = fopen(argv[1], "rb");
    destFile = fopen(argv[2], "wb");

        printf("Could not open source file\n");
        return 2;
        printf("Could not open destination file\n");
        return 3;

    while(numBytes=fread(buf, 1, 50, sourceFile))
        fwrite(buf, 1, numBytes, destFile);


    return 0;

EDIT: The glibc reference has this to say:

In general, you should stick with using streams rather than file descriptors, unless there is some specific operation you want to do that can only be done on a file descriptor. If you are a beginning programmer and aren't sure what functions to use, we suggest that you concentrate on the formatted input functions (see Formatted Input) and formatted output functions (see Formatted Output).

If you are concerned about portability of your programs to systems other than GNU, you should also be aware that file descriptors are not as portable as streams. You can expect any system running ISO C to support streams, but non-GNU systems may not support file descriptors at all, or may only implement a subset of the GNU functions that operate on file descriptors. Most of the file descriptor functions in the GNU library are included in the POSIX.1 standard, however.

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

I've found that the biggest culprit for taking up port 80 on newer Windows installs is the BranchCache Service (#3) in this list...

  1. SQL Server Reporting Services

  2. Web Deployment Agent Service

  3. BranchCache

  4. World Wide Web Publishing Service

These 4 service probably cover 90% of the native Windows Services that take up port 80.

The other 10% is the hidden HTTP.sys service/driver which takes port 80 when another service requests it. Run this to disable it, and reboot.

sc config http start= disabled

Aside from Skype, TeamViewer is also very commonly installed software, and will take port 80 if not configured otherwise.

List taken from: Opening Up Port 80 For Apache to Use On Windows


Mecki's answer is absolutly perfect, but it's worth adding that FreeBSD also supports SO_REUSEPORT_LB, which mimics Linux' SO_REUSEPORT behaviour - it balances the load; see setsockopt(2)

SVG drop shadow using css3

Easiest way I've found is with feDropShadow.

<filter id="shadow" x="0" y="0" width="200%" height="200%">
  <feDropShadow dx="40" dy="40" stdDeviation="35" flood-color="#ff0000" flood-opacity="1" />

On the element:

<path d="..." filter="url(#shadow)"/>

WPF Check box: Check changed handling

A simple and proper way I've found to Handle Checked/Unchecked events using MVVM pattern is the Following, with Caliburn.Micro :

 <CheckBox IsChecked="{Binding IsCheckedBooleanProperty}" Content="{DynamicResource DisplayContent}" cal:Message.Attach="[Event Checked] = [Action CheckBoxClicked()]; [Event Unchecked] = [Action CheckBoxClicked()]" />

And implement a Method CheckBoxClicked() in the ViewModel, to do stuff you want.

javascript password generator

I would probably use something like this:

function generatePassword() {
    var length = 8,
        charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789",
        retVal = "";
    for (var i = 0, n = charset.length; i < length; ++i) {
        retVal += charset.charAt(Math.floor(Math.random() * n));
    return retVal;

That can then be extended to have the length and charset passed by a parameter.

Fragment Inside Fragment

Since Android 4.2 (API 17) nested fragments become available

To place fragment inside other fragment use getChildFragmentManager()

It also available in support library!

getApplication() vs. getApplicationContext()

To answer the question, getApplication() returns an Application object and getApplicationContext() returns a Context object. Based on your own observations, I would assume that the Context of both are identical (i.e. behind the scenes the Application class calls the latter function to populate the Context portion of the base class or some equivalent action takes place). It shouldn't really matter which function you call if you just need a Context.

CodeIgniter PHP Model Access "Unable to locate the model you have specified"

Adding to @jakentus answer, below is what worked for me:

  1. Change the file name in the models package to Logon_model.php (First letter upper case as @jakentus correctly said)

  2. Change the class name as same as file name i.e.

    class Logon_model extends CI_Model

  3. Change the name in the load method too as


Hope this helps. Happy coding. :)

Could not resolve placeholder in string value

In your configuration you have 2 PropertySourcesPlaceholderConfigurer instances.


<bean class="">
    <property name="environment">
        <bean class=""/>


<context:property-placeholder location=""/>

By default a PlaceholderConfigurer is going to fail-fast, so if a placeholder cannot be resolved it will throw an exception. The instance from the applicationContext.xml file has no properties and as such will fail on all placeholders.

Solution: Remove the one from applicationContext.xml as it doesn't add anything it only breaks things.

What is the role of the bias in neural networks?

In a couple of experiments in my masters thesis (e.g. page 59), I found that the bias might be important for the first layer(s), but especially at the fully connected layers at the end it seems not to play a big role.

This might be highly dependent on the network architecture / dataset.

VBA changing active workbook

Use ThisWorkbook which will refer to the original workbook which holds the code.

Alternatively at code start

Dim Wb As Workbook
Set Wb = ActiveWorkbook

sample code that activates all open books before returning to ThisWorkbook

Sub Test()
Dim Wb As Workbook
Dim Wb2 As Workbook
Set Wb = ThisWorkbook
For Each Wb2 In Application.Workbooks
End Sub

Is there any simple way to convert .xls file to .csv file? (Excel)

I need to do the same thing. I ended up with something similar to Kman

       static void ExcelToCSVCoversion(string sourceFile,  string targetFile)
        Application rawData = new Application();

            Workbook workbook = rawData.Workbooks.Open(sourceFile);
            Worksheet ws = (Worksheet) workbook.Sheets[1];
            ws.SaveAs(targetFile, XlFileFormat.xlCSV);

            rawData.DisplayAlerts = false;

        Console.WriteLine($"The excel file {sourceFile} has been converted into {targetFile} (CSV format).");

If there are multiple sheets this is lost in the conversion but you could loop over the number of sheets and save each one as csv.

How to use Google fonts in React.js?

In some sort of main or first loading CSS file, just do:

@import url(',bold,italic&subset=latin,latin-ext');

You don't need to wrap in any sort of @font-face, etc. the response you get back from Google's API is ready to go and lets you use font families like normal.

Then in your main React app JavaScript, at the top put something like:

import './assets/css/fonts.css';

What I did actually was made an app.css that imported a fonts.css with a few font imports. Simply for organization (now I know where all my fonts are). The important thing to remember is that you import the fonts first.

Keep in mind that any component you import to your React app should be imported after the style import. Especially if those components also import their own styles. This way you can be sure of the ordering of styles. This is why it's best to import fonts at the top of your main file (don't forget to check your final bundled CSS file to double check if you're having trouble).

There's a few options you can pass the Google Font API to be more efficient when loading fonts, etc. See official documentation: Get Started with the Google Fonts API

Edit, note: If you are dealing with an "offline" application, then you may indeed need to download the fonts and load through Webpack.

How do I put two increment statements in a C++ 'for' loop?

Try this

for(int i = 0; i != 5; ++i, ++j)

How to get current relative directory of your Makefile?

update 2018/03/05 finnaly I use this:

shellPath=`echo $PWD/``echo ${0%/*}`

# process absolute path
shellPath1=`echo $PWD/`
shellPath2=`echo ${0%/*}`
if [ ${shellPath2:0:1} == '/' ] ; then

It can be executed correct in relative path or absolute path. Executed correct invoked by crontab. Executed correct in other shell.

show example, print self path.

[root@izbp1a7wyzv7b5hitowq2yz /]# more /root/test/
shellPath=`echo $PWD/``echo ${0%/*}`

# process absolute path
shellPath1=`echo $PWD/`
shellPath2=`echo ${0%/*}`
if [ ${shellPath2:0:1} == '/' ] ; then

echo $shellPath
[root@izbp1a7wyzv7b5hitowq2yz /]# more /root/
shellPath=`echo $PWD/``echo ${0%/*}`

# process absolute path
shellPath1=`echo $PWD/`
shellPath2=`echo ${0%/*}`
if [ ${shellPath2:0:1} == '/' ] ; then

[root@izbp1a7wyzv7b5hitowq2yz /]# ~/
[root@izbp1a7wyzv7b5hitowq2yz /]# /root/
[root@izbp1a7wyzv7b5hitowq2yz /]# cd ~
[root@izbp1a7wyzv7b5hitowq2yz ~]# ./
[root@izbp1a7wyzv7b5hitowq2yz ~]# test/
[root@izbp1a7wyzv7b5hitowq2yz ~]# cd test
[root@izbp1a7wyzv7b5hitowq2yz test]# ./
[root@izbp1a7wyzv7b5hitowq2yz test]# cd /
[root@izbp1a7wyzv7b5hitowq2yz /]# /root/test/
[root@izbp1a7wyzv7b5hitowq2yz /]# 

old: I use this:

MAKEFILE_PATH := $(PWD)/$({0%/*})

It can show correct if executed in other shell and other directory.

How to determine if a number is positive or negative?

This solution uses modulus. And yes, it also works for 0.5 (tests are below, in the main method).

public class Num {

    public static int sign(long x) {
        if (x == 0L || x == 1L) return (int) x;
        return x == Long.MIN_VALUE || x % (x - 1L) == x ? -1 : 1;

    public static int sign(double x) {
        if (x != x) throw new IllegalArgumentException("NaN");
        if (x == 0.d || x == 1.d) return (int) x;
        if (x == Double.POSITIVE_INFINITY) return 1;
        if (x == Double.NEGATIVE_INFINITY) return -1;
        return x % (x - 1.d) == x ? -1 : 1;

    public static int sign(int x) {
        return Num.sign((long)x);

    public static int sign(float x) {
        return Num.sign((double)x);

    public static void main(String args[]) {

        System.out.println(Num.sign(Integer.MAX_VALUE)); // 1
        System.out.println(Num.sign(1)); // 1
        System.out.println(Num.sign(0)); // 0
        System.out.println(Num.sign(-1)); // -1
        System.out.println(Num.sign(Integer.MIN_VALUE)); // -1

        System.out.println(Num.sign(Long.MAX_VALUE)); // 1
        System.out.println(Num.sign(1L)); // 1
        System.out.println(Num.sign(0L)); // 0
        System.out.println(Num.sign(-1L)); // -1
        System.out.println(Num.sign(Long.MIN_VALUE)); // -1

        System.out.println(Num.sign(Double.POSITIVE_INFINITY)); // 1
        System.out.println(Num.sign(Double.MAX_VALUE)); // 1
        System.out.println(Num.sign(0.5d)); // 1
        System.out.println(Num.sign(0.d)); // 0
        System.out.println(Num.sign(-0.5d)); // -1
        System.out.println(Num.sign(Double.MIN_VALUE)); // -1
        System.out.println(Num.sign(Double.NEGATIVE_INFINITY)); // -1

        System.out.println(Num.sign(Float.POSITIVE_INFINITY)); // 1
        System.out.println(Num.sign(Float.MAX_VALUE)); // 1
        System.out.println(Num.sign(0.5f)); // 1
        System.out.println(Num.sign(0.f)); // 0
        System.out.println(Num.sign(-0.5f)); // -1
        System.out.println(Num.sign(Float.MIN_VALUE)); // -1
        System.out.println(Num.sign(Float.NEGATIVE_INFINITY)); // -1
        System.out.println(Num.sign(Float.NaN)); // Throws an exception


How do I refresh a DIV content?

For div refreshing without creating div inside yours with same id, you should use this inside your function

$("#yourDiv").load(" #yourDiv > *");

Random date in C#

I have taken @Joel Coehoorn answer and made the changes he adviced - put the variable out of the method and put all in class. Plus now the time is random too. Here is the result.

class RandomDateTime
    DateTime start;
    Random gen;
    int range;

    public RandomDateTime()
        start = new DateTime(1995, 1, 1);
        gen = new Random();
        range = (DateTime.Today - start).Days;

    public DateTime Next()
        return start.AddDays(gen.Next(range)).AddHours(gen.Next(0,24)).AddMinutes(gen.Next(0,60)).AddSeconds(gen.Next(0,60));

And example how to use to write 100 random DateTimes to console:

RandomDateTime date = new RandomDateTime();
for (int i = 0; i < 100; i++)

JS. How to replace html element with another element/text, represented in string?

As the Jquery replaceWith() code was too bulky, tricky and complicated, here's my own solution. =)

The best way is to use outerHTML property, but it is not crossbrowsered yet, so I did some trick, weird enough, but simple.

Here is the code

var str = '<a href="">item to replace</a>'; //it can be anything
var Obj = document.getElementById('TargetObject'); //any element to be fully replaced
if(Obj.outerHTML) { //if outerHTML is supported
    Obj.outerHTML=str; ///it's simple replacement of whole element with contents of str var
else { //if outerHTML is not supported, there is a weird but crossbrowsered trick
    var tmpObj=document.createElement("div");
    tmpObj.innerHTML='<!--THIS DATA SHOULD BE REPLACED-->';
    ObjParent=Obj.parentNode; //Okey, element should be parented
    ObjParent.replaceChild(tmpObj,Obj); //here we placing our temporary data instead of our target, so we can find it then and replace it into whatever we want to replace to
    ObjParent.innerHTML=ObjParent.innerHTML.replace('<div><!--THIS DATA SHOULD BE REPLACED--></div>',str);

That's all

Angular 2 router.navigate

import { ActivatedRoute } from '@angular/router';_x000D_
export class ClassName {_x000D_
  private router = ActivatedRoute;_x000D_
    constructor(r: ActivatedRoute) {_x000D_
        this.router =r;_x000D_
onSuccess() {_x000D_
         {queryParams: {email: loginEmail, code: userCode}});_x000D_
Get this values:_x000D_
ngOnInit() {_x000D_
        .subscribe(params => {_x000D_
            let code = params['code'];_x000D_
            let userEmail = params['email'];_x000D_


How to make a deep copy of Java ArrayList

public class Person{

    String s;
    Date d;

    public Person clone(){
        Person p = new Person();
        p.s = this.s.clone();
        p.d = this.d.clone();
        return p;

In your executing code:

ArrayList<Person> clone = new ArrayList<Person>();
for(Person p : originalList)

How to cd into a directory with space in the name?

Use the backslash symbol to escape the space

C:\> cd my folder

will be

 C:\> cd my\folder 

How do I programmatically set the value of a select box element using JavaScript?

If you are using jQuery you can also do this:


This will select the <option> with the value of 14.

With plain Javascript, this can also be achieved with two Document methods:

  • With document.querySelector, you can select an element based on a CSS selector:

    document.querySelector('#leaveCode').value = '14'
  • Using the more established approach with document.getElementById(), that will, as the name of the function implies, let you select an element based on its id:

    document.getElementById('leaveCode').value = '14'

You can run the below code snipped to see these methods and the jQuery function in action:

const jQueryFunction = () => {_x000D_
  $('#leaveCode').val('14'); _x000D_
const querySelectorFunction = () => {_x000D_
  document.querySelector('#leaveCode').value = '14' _x000D_
const getElementByIdFunction = () => {_x000D_
  document.getElementById('leaveCode').value='14' _x000D_
input {_x000D_
  margin: 10px;_x000D_
  padding: 10px_x000D_
<select id="leaveCode" name="leaveCode">_x000D_
  <option value="10">Annual Leave</option>_x000D_
  <option value="11">Medical Leave</option>_x000D_
  <option value="14">Long Service</option>_x000D_
  <option value="17">Leave Without Pay</option>_x000D_
<input type="button" value="$('#leaveCode').val('14');" onclick="jQueryFunction()" />_x000D_
<input type="button" value="document.querySelector('#leaveCode').value = '14'" onclick="querySelectorFunction()" />_x000D_
<input type="button" value="document.getElementById('leaveCode').value = '14'" onclick="getElementByIdFunction()" />_x000D_
<script src=""></script>

Easiest way to copy a single file from host to Vagrant guest?

Try this.. vagrant ubuntu 14.04 This worked for me.

scp -r -P 2222 vagrant@localhost:/home .

How do I change an HTML selected option using JavaScript?

If you are adding the option with javascript

function AddNewOption(userRoutes, text, id) 
    var option = document.createElement("option");
    option.text = text;
    option.value = id;
    option.selected = "selected";

Use grep --exclude/--include syntax to not grep through certain files

The --binary-files=without-match option to GNU grep gets it to skip binary files. (Equivalent to the -I switch mentioned elsewhere.)

(This might require a recent version of grep; 2.5.3 has it, at least.)

missing private key in the distribution certificate on keychain

To add on to others' answers, if you don't have access to that private key anymore it's fairly simple to get back up and running:

  1. revoke your active certificate in the provisioning portal
  2. create new developer certificate (keychain access/.../request for csr...etc.)
  3. download and install a new certificate
  4. create a new provisioning profile for existing app id (on provisioning portal)
  5. download and install new provisioning profile and in the build, settings set the appropriate code signing identities

Clear text from textarea with selenium

With a simple call of clear() it appears in the DOM that the corresponding input/textarea component still has its old value, so any following changes on that component (e.g. filling the component with a new value) will not be processed in time.

If you take a look in the selenium source code you'll find that the clear()-method is documented with the following comment:

/** If this element is a text entry element, this will clear the value. Has no effect on other elements. Text entry elements are INPUT and TEXTAREA elements. Note that the events fired by this event may not be as you'd expect. In particular, we don't fire any keyboard or mouse events. If you want to ensure keyboard events are fired, consider using something like {@link #sendKeys(CharSequence...)} with the backspace key. To ensure you get a change event, consider following with a call to {@link #sendKeys(CharSequence...)} with the tab key. */

So using this helpful hint to clear an input/textarea (component that already has a value) AND assign a new value to it, you'll get some code like the following:

public void waitAndClearFollowedByKeys(By by, CharSequence keys) {
    LOG.debug("clearing element");
    wait(by, true).clear();
    sendKeys(by, Keys.BACK_SPACE.toString() + keys);

public void sendKeys(By by, CharSequence keysToSend) {
    WebElement webElement = wait(by, true);"sending keys '{}' to {}", escapeProperly(keysToSend), by);
    webElement.sendKeys(keysToSend);"keys sent");

private String escapeProperly(CharSequence keysToSend) {
    String result = "" + keysToSend;
    result = result.replace(Keys.TAB, "\\t");
    result = result.replace(Keys.ENTER, "\\n");
    result = result.replace(Keys.RETURN, "\\r");

    return result;

Sorry for this code being Java and not Python. Also, I had to skip out an additional "waitUntilPageIsReady()-method that would make this post way too long.

Hope this helps you on your journey with Selenium!

Multiple WHERE clause in Linq

Well, you can just put multiple "where" clauses in directly, but I don't think you want to. Multiple "where" clauses ends up with a more restrictive filter - I think you want a less restrictive one. I think you really want:

DataTable tempData = (DataTable)grdUsageRecords.DataSource;
var query = from r in tempData.AsEnumerable()
            where r.Field<string>("UserName") != "XXXX" &&
                  r.Field<string>("UserName") != "YYYY"
            select r;

DataTable newDT = query.CopyToDataTable();

Note the && instead of ||. You want to select the row if the username isn't XXXX and the username isn't YYYY.

EDIT: If you have a whole collection, it's even easier. Suppose the collection is called ignoredUserNames:

DataTable tempData = (DataTable)grdUsageRecords.DataSource;
var query = from r in tempData.AsEnumerable()
            where !ignoredUserNames.Contains(r.Field<string>("UserName"))
            select r;

DataTable newDT = query.CopyToDataTable();

Ideally you'd want to make this a HashSet<string> to avoid the Contains call taking a long time, but if the collection is small enough it won't make much odds.

m2e error in MavenArchiver.getManifest()

Use the steps given in this link. It worked for me.

Step - 1 Right click on your project in Eclipse

Step - 2 Click Properties

Step - 3 Select Maven in the left hand side list.

Step - 4 You will notice "pom.xml" in the Active Maven Profiles text box on the right hand side. Clear it and click Apply.

Step - 5 Run As -> Maven clean -> Maven Install

Hope it helps!

Node.js getaddrinfo ENOTFOUND

I got rid of http and extra slash(/). I just used this '' and it worked.

Connect to Amazon EC2 file directory using Filezilla and SFTP

Make sure you use port 22. Filezilla will default to port 21 for SFTP.

Calling Member Functions within Main C++

From your question it is unclear if you want to be able use the class without an identity or if calling the method requires you to create an instance of the class. This depends on whether you want the printInformation member to write some general information or more specific about the object identity.

Case 1: You want to use the class without creating an instance. The members of that class should be static, using this keyword you tell the compiler that you want to be able to call the method without having to create a new instance of the class.

class MyClass
    static void printInformation();

Case 2: You want the class to have an instance, you first need to create an object so that the class has an identity, once that is done you can use the object his methods.

Myclass m;

// Or, in the case that you want to use pointers:
Myclass * m = new Myclass();

If you don't know when to use pointers, read Pukku's summary in this Stack Overflow question.
Please note that in the current case you would not need a pointer. :-)

What's the easy way to auto create non existing dir in ansible

To ensure success with a full path use recurse=yes

- name: ensure custom facts directory exists
    file: >

XAMPP, Apache - Error: Apache shutdown unexpectedly

i also got the same error and i was uninstall vmware to fix that error.

Best way to detect Mac OS X or Windows computers with JavaScript or jQuery

Let me know if this works. Way to detect an Apple device (Mac computers, iPhones, etc.) with help from
What is the list of possible values for navigator.platform as of today?

var deviceDetect = navigator.platform;
var appleDevicesArr = ['MacIntel', 'MacPPC', 'Mac68K', 'Macintosh', 'iPhone', 
'iPod', 'iPad', 'iPhone Simulator', 'iPod Simulator', 'iPad Simulator', 'Pike 
v7.6 release 92', 'Pike v7.8 release 517'];

// If on Apple device
if(appleDevicesArr.includes(deviceDetect)) {
    // Execute code
// If NOT on Apple device
else {
    // Execute code

How to write a std::string to a UTF-8 text file

There is nice tiny library to work with utf8 from c++: utfcpp

How to convert ActiveRecord results into an array of hashes


You should use as_json method which converts ActiveRecord objects to Ruby Hashes despite its name

tasks_records = TaskStoreStatus.all
tasks_records = tasks_records.as_json

# You can now add new records and return the result as json by calling `to_json`

tasks_records << TaskStoreStatus.last.as_json
tasks_records << { :task_id => 10, :store_name => "Koramanagala", :store_region => "India" }


You can also convert any ActiveRecord objects to a Hash with serializable_hash and you can convert any ActiveRecord results to an Array with to_a, so for your example :

tasks_records = TaskStoreStatus.all

And if you want an ugly solution for Rails prior to v2.3

JSON.parse(tasks_records.to_json) # please don't do it

jquery onclick change css background image

You need to use background-image instead of backgroundImage. For example:

$(function() {
  $('.home').click(function() {
    $(this).css('background-image', 'url(images/tabs3.png)');

regular expression to match exactly 5 digits

This should work:

<script type="text/javascript">
var testing='this is d23553 test 32533\n31203 not 333';
var r = new RegExp(/(?:^|[^\d])(\d{5})(?:$|[^\d])/mg);
var matches = [];
while ((match = r.exec(testing))) matches.push(match[1]);
alert('Found: '+matches.join(', '));

How to fix IndexError: invalid index to scalar variable

You are trying to index into a scalar (non-iterable) value:

[y[1] for y in y_test]
#  ^ this is the problem

When you call [y for y in test] you are iterating over the values already, so you get a single value in y.

Your code is the same as trying to do the following:

y_test = [1, 2, 3]
y = y_test[0] # y = 1
print(y[0]) # this line will fail

I'm not sure what you're trying to get into your results array, but you need to get rid of [y[1] for y in y_test].

If you want to append each y in y_test to results, you'll need to expand your list comprehension out further to something like this:

[results.append(..., y) for y in y_test]

Or just use a for loop:

for y in y_test:
    results.append(..., y)

change html input type by JS?

Here is what I have for mine.

Essentially you are utilizing the onfocus and onblur commands in the tag to trigger the appropriate javascript. It could be as simple as:

<span><input name="login_text_password" type="text" value="Password" onfocus="; this.setAttribute('type','password');" onblur="; this.setAttribute('type','text');" /></span>

An evolved version of this basic functionality checks for and empty string and returns the password input back to the original "Password" in the event of a null textbox:

    <script type="text/javascript">
        function password_set_attribute() {
            if (document.getElementsByName("login_text_password")[0].value.replace(/\s+/g, ' ') == "" || document.getElementsByName[0].value == null) {
                document.getElementsByName("login_text_password")[0].value = 'Password';
            else {

Where HTML looks like:

<span><input name="login_text_password" class="roundCorners" type="text" value="Password" onfocus="; this.setAttribute('type','password');" onblur="password_set_attribute();" /></span>

How do I convert a IPython Notebook into a Python file via commandline?

There's a very nice package called nb_dev which is designed for authoring Python packages in Jupyter Notebooks. Like nbconvert, it can turn a notebook into a .py file, but it is more flexible and powerful because it has a lot of nice additional authoring features to help you develop tests, documentation, and register packages on PyPI. It was developed by the folks.

It has a bit of a learning curve, but the documentation is good and it is not difficult overall.

How to update array value javascript?

function Update(key, value)
    for (var i = 0; i < array.length; i++) {
        if (array[i].Key == key) {
            array[i].Value = value; 

What is the difference between Document style and RPC style communication?

Can some body explain me the differences between a Document style and RPC style webservices?

There are two communication style models that are used to translate a WSDL binding to a SOAP message body. They are: Document & RPC

The advantage of using a Document style model is that you can structure the SOAP body any way you want it as long as the content of the SOAP message body is any arbitrary XML instance. The Document style is also referred to as Message-Oriented style.

However, with an RPC style model, the structure of the SOAP request body must contain both the operation name and the set of method parameters. The RPC style model assumes a specific structure to the XML instance contained in the message body.

Furthermore, there are two encoding use models that are used to translate a WSDL binding to a SOAP message. They are: literal, and encoded

When using a literal use model, the body contents should conform to a user-defined XML-schema(XSD) structure. The advantage is two-fold. For one, you can validate the message body with the user-defined XML-schema, moreover, you can also transform the message using a transformation language like XSLT.

With a (SOAP) encoded use model, the message has to use XSD datatypes, but the structure of the message need not conform to any user-defined XML schema. This makes it difficult to validate the message body or use XSLT based transformations on the message body.

The combination of the different style and use models give us four different ways to translate a WSDL binding to a SOAP message.


I would recommend that you read this article entitled Which style of WSDL should I use? by Russell Butek which has a nice discussion of the different style and use models to translate a WSDL binding to a SOAP message, and their relative strengths and weaknesses.

Once the artifacts are received, in both styles of communication, I invoke the method on the port. Now, this does not differ in RPC style and Document style. So what is the difference and where is that difference visible?

The place where you can find the difference is the "RESPONSE"!

RPC Style:

package com.sample;

import java.util.ArrayList;
import javax.jws.WebService;
import javax.jws.soap.SOAPBinding;
import javax.jws.soap.SOAPBinding.Style;

public interface StockPrice { 

    public String getStockPrice(String stockName); 

    public ArrayList getStockPriceList(ArrayList stockNameList); 

The SOAP message for second operation will have empty output and will look like:

RPC Style Response:


Document Style:

package com.sample;

import java.util.ArrayList;
import javax.jws.WebService;
import javax.jws.soap.SOAPBinding;
import javax.jws.soap.SOAPBinding.Style;

public interface StockPrice {

    public String getStockPrice(String stockName);

    public ArrayList getStockPriceList(ArrayList stockNameList);

If we run the client for the above SEI, the output is:

123 [123, 456]

This output shows that ArrayList elements are getting exchanged between the web service and client. This change has been done only by the changing the style attribute of SOAPBinding annotation. The SOAP message for the second method with richer data type is shown below for reference:

Document Style Response:

<return xmlns:xsi=""  
<return xmlns:xsi=""


  • As you would have noticed in the two SOAP response messages that it is possible to validate the SOAP response message in case of DOCUMENT style but not in RPC style web services.
  • The basic disadvantage of using RPC style is that it doesn’t support richer data types and that of using Document style is that it brings some complexity in the form of XSD for defining the richer data types.
  • The choice of using one out of these depends upon the operation/method requirements and the expected clients.

Similarly, in what way SOAP over HTTP differ from XML over HTTP? After all SOAP is also XML document with SOAP namespace. So what is the difference here?

Why do we need a standard like SOAP? By exchanging XML documents over HTTP, two programs can exchange rich, structured information without the introduction of an additional standard such as SOAP to explicitly describe a message envelope format and a way to encode structured content.

SOAP provides a standard so that developers do not have to invent a custom XML message format for every service they want to make available. Given the signature of the service method to be invoked, the SOAP specification prescribes an unambiguous XML message format. Any developer familiar with the SOAP specification, working in any programming language, can formulate a correct SOAP XML request for a particular service and understand the response from the service by obtaining the following service details.

  • Service name
  • Method names implemented by the service
  • Method signature of each method
  • Address of the service implementation (expressed as a URI)

Using SOAP streamlines the process for exposing an existing software component as a Web service since the method signature of the service identifies the XML document structure used for both the request and the response.

How to add two edit text fields in an alert dialog

The API Demos in the Android SDK have an example that does just that.

It's under DIALOG_TEXT_ENTRY. They have a layout, inflate it with a LayoutInflater, and use that as the View.

EDIT: What I had linked to in my original answer is stale. Here is a mirror.

Differences between cookies and sessions?

Cookies and session both store information about the user (to make the HTTP request stateful) but the difference is that cookies store information on the client-side (browser) and sessions store information on the server-side. A cookie is limited in the sense that it stores information about limited users and only stores limited content for each user. A session is not limit in such a way.

How do I fix this "TypeError: 'str' object is not callable" error?

this part :

"Your new price is: $"(float(price)

asks python to call this string:

"Your new price is: $"

just like you would a function: function( some_args) which will ALWAYS trigger the error:

TypeError: 'str' object is not callable

How do I delete virtual interface in Linux?

Have you tried:

ifconfig 10:35978f0 down

As the physical interface is 10 and the virtual aspect is after the colon :.

See also

Is it possible to install iOS 6 SDK on Xcode 5?

I downloaded XCode 4 and took iOS 6.1 SDK from it to the XCode 5 as described in other answers. Then I also installed iOS 6.1 Simulator (it was available in preferences). I also switched Base SDK to iOS 6.1 in project settings.

After all these manipulations the project with 6.1 base sdk runs in comp ability mode in iOS 7 Simulator.

libstdc++-6.dll not found

Simply removing libstdc++-6.dll.a \ libstdc++.dll.a from the mingw directory fixes this.

I tried using the flag -static-libstdc++ but this did not work for me. I found the solution in:

Send JSON data from Javascript to PHP?

PHP has a built in function called json_decode(). Just pass the JSON string into this function and it will convert it to the PHP equivalent string, array or object.

In order to pass it as a string from Javascript, you can convert it to JSON using


or a library such as Prototype

Convert string to date in Swift

Swift 3.0 - 4.2

import Foundation

extension String {

    func toDate(withFormat format: String = "yyyy-MM-dd HH:mm:ss")-> Date?{

        let dateFormatter = DateFormatter()
        dateFormatter.timeZone = TimeZone(identifier: "Asia/Tehran")
        dateFormatter.locale = Locale(identifier: "fa-IR")
        dateFormatter.calendar = Calendar(identifier: .gregorian)
        dateFormatter.dateFormat = format
        let date = self)

        return date


extension Date {

    func toString(withFormat format: String = "EEEE ? d MMMM yyyy") -> String {

        let dateFormatter = DateFormatter()
        dateFormatter.locale = Locale(identifier: "fa-IR")
        dateFormatter.timeZone = TimeZone(identifier: "Asia/Tehran")
        dateFormatter.calendar = Calendar(identifier: .persian)
        dateFormatter.dateFormat = format
        let str = dateFormatter.string(from: self)

        return str

HTTP Basic Authentication - what's the expected web browser experience?

You can use Postman a plugin for chrome. It gives the ability to choose the authentication type you need for each of the requests. In that menu you can configure user and password. Postman will automatically translate the config to a authentication header that will be sent with your request.

What's the best way to test SQL Server connection programmatically?

Wouldn't establishing a connection to the database do this for you? If the database isn't up you won't be able to establish a connection.

Facebook Open Graph not clearing cache

I had the same issues using og:image, several attempts to rename the file or clear FB cache did not work either via the facebook debugger or testing via an actual account.

The new facebook guidelines state the image size should be 1200 x 630 or having that aspect ratio, this seems to be wrong, the only thing that worked for me was using an image with square dimensions.

Edit* Afew hours I went back to use 1200 x 630 and it magically worked, it was magical.

I also renamed the files to f*^*kfacebook.jpg, not sure it helped but it felt good.

Java: Check if command line arguments are null

if i want to check if any speicfic position of command line arguement is passed or not then how to check? like for example in some scenarios 2 command line args will be passed and in some only one will be passed then how do it check wheather the specfic commnad line is passed or not?

public class check {

public static void main(String[] args) {
System.out.println("entered first if");
if(args[0].length()!=0 && args[1].length()!=0)
System.out.println("entered second if");

So in the above code if args[1] is not passed then i get java.lang.ArrayIndexOutOfBoundsException:

so how do i tackle this where i can check if second arguement is passed or not and if passed then enter it. need assistance asap.

How to Free Inode Usage?

In one of the above answers it was suggested that sessions was the cause of running out of inodes and in our case that is exactly what it was. To add to that answer though I would suggest to check the php.ini file and ensure session.gc_probability = 1 also session.gc_divisor = 1000 and session.gc_maxlifetime = 1440. In our case session.gc_probability was equal to 0 and caused this issue.

Importing a function from a class in another file?

from otherfile import TheClass
theclass = TheClass()
# if you want to return the output of run
# if you want to return run itself to be used later

Change the end of comm system to:

if __name__ == '__main__':
    a_game = Comm_system()

It's those lines being always run that are causing it to be run when imported as well as when executed.

Auto-refreshing div with jQuery - setTimeout or another method?

Another modification:

function update() {
  $.get("response.php", function(data) {
    window.setTimeout(update, 10000);

The difference with this is that it waits 10 seconds AFTER the ajax call is one. So really the time between refreshes is 10 seconds + length of ajax call. The benefit of this is if your server takes longer than 10 seconds to respond, you don't get two (and eventually, many) simultaneous AJAX calls happening.

Also, if the server fails to respond, it won't keep trying.

I've used a similar method in the past using .ajax to handle even more complex behaviour:

function update() {
    type: 'GET',
    url: 'response.php',
    timeout: 2000,
    success: function(data) {
      window.setTimeout(update, 10000);
    error: function (XMLHttpRequest, textStatus, errorThrown) {
      $("#notice_div").html('Timeout contacting server..');
      window.setTimeout(update, 60000);

This shows a loading message while loading (put an animated gif in there for typical "web 2.0" style). If the server times out (in this case takes longer than 2s) or any other kind of error happens, it shows an error, and it waits for 60 seconds before contacting the server again.

This can be especially beneficial when doing fast updates with a larger number of users, where you don't want everyone to suddenly cripple a lagging server with requests that are all just timing out anyways.

Enable the display of line numbers in Visual Studio

In Visual Studio 2013 & 2015 :

Tools -> Options -> Text Editor -> All Languages -> check Line Numbers enter image description here

Difference between `constexpr` and `const`

As @0x499602d2 already pointed out, const only ensures that a value cannot be changed after initialization where as constexpr (introduced in C++11) guarantees the variable is a compile time constant.
Consider the following example(from

cout << "Enter your age: ";
int age;
cin >> age;

const int myAge{age};        // works
constexpr int someAge{age};  // error: age can only be resolved at runtime

X-Frame-Options on apache

  1. You can add to .htaccess, httpd.conf or VirtualHost section
  2. Header set X-Frame-Options SAMEORIGIN this is the best option

Allow from URI is not supported by all browsers. Reference: X-Frame-Options on MDN

Could not find method compile() for arguments Gradle

Just for the record: I accidentally enabled Offline work under Preferences -> Build,Execution,Deployment -> Gradle -> uncheck Offline Work, but the error message was misleading

Animate background image change with jQuery

Ok, I figured it out, this is pretty simple with a little html trick:


    <div id="background">.
    <p>hello world</p>
    <p>hello world</p>
    <p>hello world</p>
    <p>hello world</p>    


    $('#background').animate({ opacity: 1 }, 3000);


#background {
    background-image: url("");
    opacity: 0;
    margin: 0;
    padding: 0;
    z-index: -1;
    position: absolute;
    width: 100%;
    height: 100%;

Java: Static vs inner class

An inner class, by definition, cannot be static, so I am going to recast your question as "What is the difference between static and non-static nested classes?"

A non-static nested class has full access to the members of the class within which it is nested. A static nested class does not have a reference to a nesting instance, so a static nested class cannot invoke non-static methods or access non-static fields of an instance of the class within which it is nested.

using CASE in the WHERE clause

This is working Oracle example but it should work in MySQL too.

You are missing smth - see IN after END Replace 'IN' with '=' sign for a single value.

SELECT empno, ename, job
  FROM scott.emp
         WHEN job = 'CLERK'   THEN '2' 
         ELSE '0'  END) IN (1, 2)

What's the function like sum() but for multiplication? product()?

I prefer the answers a and b above using functools.reduce() and the answer using, but here is yet another solution using itertools.accumulate():

import itertools
import operator
prod = list(itertools.accumulate((3, 4, 5), operator.mul))[-1]

Object Library Not Registered When Adding Windows Common Controls 6.0

On 32-bit machines:

cd C:\Windows\System32
regsvr32 mscomctl.ocx
regtlib msdatsrc.tlb

or on 64 bit machines:

cd C:\Windows\SysWOW64
regsvr32 mscomctl.ocx
regtlib msdatsrc.tlb

These need to be run as administrator.

Custom UITableViewCell from nib in Swift

I had to make sure that when creating the outlet to specify that I was hooking to the cell, not the object's owner. When the menu appears to name it you have to select it in the 'object' dropdown menu. Of course you must declare the cell as your class too, not just 'TableViewCellClass'. Otherwise I would keep getting the class not key compliant.

OSError - Errno 13 Permission denied

Probably you are facing problem when a download request is made by the maybe_download function call in file.

There is a conflict in the permissions of the temporary files and I myself couldn't work out a way to change the permissions, but was able to work around the problem.

Do the following...

  • Download the four .gz files of the MNIST data set from the link ( )
  • Then make a folder names MNIST_data (or your choice in your working directory/ site packages folder in the tensorflow\examples folder).
  • Directly copy paste the files into the folder.
  • Copy the address of the folder (it probably will be ( C:\Python\Python35\Lib\site-packages\tensorflow\examples\tutorials\mnist\MNIST_data ))
  • Change the "\" to "/" as "\" is used for escape characters, to access the folder locations.
  • Lastly, if you are following the tutorials, your call function would be ( mnist = input_data.read_data_sets("MNIST_data/", one_hot=True) ) ; change the "MNIST_data/" parameter to your folder location. As in my case would be ( mnist = input_data.read_data_sets("C:/Python/Python35/Lib/site-packages/tensorflow/examples/tutorials/mnist/MNIST_data", one_hot=True) )

Then it's all done. Hope it works for you.

HTML5 Video tag not working in Safari , iPhone and iPad

Your web server might not support HTTP byte-range requests. This is the case with the web server I'm using, and the result is that the video widget loads and a play button appears, but clicking the button has no effect. — The video works in FF and Chrome, but not iPhone or iPad.

Read more here on about byte-range requests, in Appendix A: Streaming for Apple iPhone:

First, the Safari Web Browser requests the content, and if it's an audio or video file it opens it's media player. The media player then requests the first 2 bytes of the content, to ensure that the Webserver supports byte-range requests. Then, if it supports them, the iPhone's media player requests the rest of the content by byte-ranges and plays it.

You might want to search the web for "iphone mp4 byte-range".

How to copy multiple files in one layer using a Dockerfile?

COPY package.json gulpfile.js __BUILD_NUMBER ./


COPY ["__BUILD_NUMBER", "", "gulpfile", "another_file", "./"]

You can also use wildcard characters in the sourcefile specification. See the docs for a little more detail.

Directories are special! If you write

COPY dir1 dir2 ./

that actually works like

COPY dir1/* dir2/* ./

If you want to copy multiple directories (not their contents) under a destination directory in a single command, you'll need to set up the build context so that your source directories are under a common parent and then COPY that parent.

How to disable Django's CSRF validation?

To disable CSRF for class based views the following worked for me.
Using django 1.10 and python 3.5.2

from django.views.decorators.csrf import csrf_exempt
from django.utils.decorators import method_decorator

@method_decorator(csrf_exempt, name='dispatch')
class TestView(View):
    def post(self, request, *args, **kwargs):
        return HttpResponse('Hello world')

How are booleans formatted in Strings in Python?

You may also use the Formatter class of string

print "{0} {1}".format(True, False);
print "{0:} {1:}".format(True, False);
print "{0:d} {1:d}".format(True, False);
print "{0:f} {1:f}".format(True, False);
print "{0:e} {1:e}".format(True, False);

These are the results

True False
True False
1 0
1.000000 0.000000
1.000000e+00 0.000000e+00

Some of the %-format type specifiers (%r, %i) are not available. For details see the Format Specification Mini-Language

Set ANDROID_HOME environment variable in mac

Based on Abraham Mayowa Oluwasina answer provided above is the correct one. MacOS Catalina, .bash_profile is no longer apple's default shell and it won't persist your path variables instead use .zprofile instead.

In root directory,

touch .zprofile
open -e .zprofile

Add the following in file,

export ANDROID_HOME=/Users/<username>/Library/Android/sdk
export PATH=$PATH:$ANDROID_HOME/platform-tools

Save and exit

To activate

source ~/. zprofile


Check if element found in array c++

You would just do the same thing, looping through the array to search for the term you want. Of course if it's a sorted array this would be much faster, so something similar to prehaps:

for(int i = 0; i < arraySize; i++){
     if(array[i] == itemToFind){

Get file content from URL?

1) local simplest methods

echo readfile("");   //needs "Allow_url_include" enabled
echo include("");    //needs "Allow_url_include" enabled
echo file_get_contents("");
echo stream_get_contents(fopen('', "rb")); //you may use "r" instead of "rb"  //needs "Allow_url_fopen" enabled

2) Better Way is CURL:

echo get_remote_data(''); // GET request 
echo get_remote_data('', "var2=something&var3=blabla" ); // POST request

It automatically handles FOLLOWLOCATION problem + Remote urls:
src="./imageblabla.png" turned into:

Code :

How to rsync only a specific list of files?

Edit: atp's answer below is better. Please use that one!

You might have an easier time, if you're looking for a specific list of files, putting them directly on the command line instead:

# rsync -avP -e ssh `cat deploy/rsync_include.txt` [email protected]:/var/www/

This is assuming, however, that your list isn't so long that the command line length will be a problem and that the rsync_include.txt file contains just real paths (i.e. no comments, and no regexps).

How to convert a UTF-8 string into Unicode?

If you have a UTF-8 string, where every byte is correct ('Ö' -> [195, 0] , [150, 0]), you can use the following:

public static string Utf8ToUtf16(string utf8String)
     * Every .NET string will store text with the UTF-16 encoding, *
     * known as Encoding.Unicode. Other encodings may exist as     *
     * Byte-Array or incorrectly stored with the UTF-16 encoding.  *
     *                                                             *
     * UTF-8 = 1 bytes per char                                    *
     *    ["100" for the ansi 'd']                                 *
     *    ["206" and "186" for the russian '?']                    *
     *                                                             *
     * UTF-16 = 2 bytes per char                                   *
     *    ["100, 0" for the ansi 'd']                              *
     *    ["186, 3" for the russian '?']                           *
     *                                                             *
     * UTF-8 inside UTF-16                                         *
     *    ["100, 0" for the ansi 'd']                              *
     *    ["206, 0" and "186, 0" for the russian '?']              *
     *                                                             *
     * First we need to get the UTF-8 Byte-Array and remove all    *
     * 0 byte (binary 0) while doing so.                           *
     *                                                             *
     * Binary 0 means end of string on UTF-8 encoding while on     *
     * UTF-16 one binary 0 does not end the string. Only if there  *
     * are 2 binary 0, than the UTF-16 encoding will end the       *
     * string. Because of .NET we don't have to handle this.       *
     *                                                             *
     * After removing binary 0 and receiving the Byte-Array, we    *
     * can use the UTF-8 encoding to string method now to get a    *
     * UTF-16 string.                                              *
     *                                                             *

    // Get UTF-8 bytes and remove binary 0 bytes (filler)
    List<byte> utf8Bytes = new List<byte>(utf8String.Length);
    foreach (byte utf8Byte in utf8String)
        // Remove binary 0 bytes (filler)
        if (utf8Byte > 0) {

    // Convert UTF-8 bytes to UTF-16 string
    return Encoding.UTF8.GetString(utf8Bytes.ToArray());

In my case the DLL result is a UTF-8 string too, but unfortunately the UTF-8 string is interpreted with UTF-16 encoding ('Ö' -> [195, 0], [19, 32]). So the ANSI '–' which is 150 was converted to the UTF-16 '–' which is 8211. If you have this case too, you can use the following instead:

public static string Utf8ToUtf16(string utf8String)
    // Get UTF-8 bytes by reading each byte with ANSI encoding
    byte[] utf8Bytes = Encoding.Default.GetBytes(utf8String);

    // Convert UTF-8 bytes to UTF-16 bytes
    byte[] utf16Bytes = Encoding.Convert(Encoding.UTF8, Encoding.Unicode, utf8Bytes);

    // Return UTF-16 bytes as UTF-16 string
    return Encoding.Unicode.GetString(utf16Bytes);

Or the Native-Method:

private static extern Int32 MultiByteToWideChar(UInt32 CodePage, UInt32 dwFlags, [MarshalAs(UnmanagedType.LPStr)] String lpMultiByteStr, Int32 cbMultiByte, [Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder lpWideCharStr, Int32 cchWideChar);

public static string Utf8ToUtf16(string utf8String)
    Int32 iNewDataLen = MultiByteToWideChar(Convert.ToUInt32(Encoding.UTF8.CodePage), 0, utf8String, -1, null, 0);
    if (iNewDataLen > 1)
        StringBuilder utf16String = new StringBuilder(iNewDataLen);
        MultiByteToWideChar(Convert.ToUInt32(Encoding.UTF8.CodePage), 0, utf8String, -1, utf16String, utf16String.Capacity);

        return utf16String.ToString();
        return String.Empty;

If you need it the other way around, see Utf16ToUtf8. Hope I could be of help.

In Mongoose, how do I sort by date? (node.js)

Been dealing with this issue today using Mongoose 3.5(.2) and none of the answers quite helped me solve this issue. The following code snippet does the trick

Post.find().sort('-posted').find(function (err, posts) {
    // user posts array

You can send any standard parameters you need to find() (e.g. where clauses and return fields) but no callback. Without a callback it returns a Query object which you chain sort() on. You need to call find() again (with or without more parameters -- shouldn't need any for efficiency reasons) which will allow you to get the result set in your callback.

How can I get the current stack trace in Java?

I have a utility method that returns a string with the stacktrace:

static String getStackTrace(Throwable t) {
    StringWriter sw = new StringWriter();
    PrintWriter pw = new PrintWriter(sw, true);
    return sw.toString();

And just logit like...

catch (FileNotFoundException e) {

jQuery changing style of HTML element

changing style with jquery

Try This


You can also change multiple attribute in a single query

Try This

$('#replace-div').css({'padding-top': '5px' , 'margin' : '10px'});

define a List like List<int,string>?

Use C# Dictionary datastructure it good for you...

Dictionary<string, int> dict = new Dictionary<string, int>();
dict.Add("one", 1);
dict.Add("two", 2);

You can retrieve data from Ditionary in a simple way..

foreach (KeyValuePair<string, int> pair in dict)
    MessageBox.Show(pair.Key.ToString ()+ "  -  "  + pair.Value.ToString () );

For more example using C# Dictionary... C# Dictionary


Programmatically Lighten or Darken a hex color (or rgb, and blend colors)

have you thought about an rgb > hsl conversion? then just move the Luminosity up and down? thats the way I would go.

A quick look for some algorithms got me the following sites.



EDIT the above link is no longer valid. You can view git hub for the page source or the gist

Alternatively another StackOverflow question might be a good place to look.

Even though this is not the right choice for the OP the following is an approximation of the code I was originally suggesting. (Assuming you have rgb/hsl conversion functions)


function lightenShade(colorValue)
    if(colorValue && colorValue.length >= 6)
        var redValue = parseInt(colorValue.slice(-6,-4), 16);
        var greenValue = parseInt(colorValue.slice(-4,-2), 16);
        var blueValue = parseInt(colorValue.slice(-2), 16);

        var hsl = rgbToHsl(redValue, greenValue, blueValue);
        hsl[2]= Math.min(hsl[2] + SHADE_SHIFT_AMOUNT, 1);
        var rgb = hslToRgb(hsl[0], hsl[1], hsl[2]);
        return "#" + rgb[0].toString(16) + rgb[1].toString(16) + rgb[2].toString(16);
    return null;

function darkenShade(colorValue)
    if(colorValue && colorValue.length >= 6)
        var redValue = parseInt(colorValue.slice(-6,-4), 16);
        var greenValue = parseInt(colorValue.slice(-4,-2), 16);
        var blueValue = parseInt(colorValue.slice(-2), 16);

        var hsl = rgbToHsl(redValue, greenValue, blueValue);
        hsl[2]= Math.max(hsl[2] - SHADE_SHIFT_AMOUNT, 0);
        var rgb = hslToRgb(hsl[0], hsl[1], hsl[2]);
        return "#" + rgb[0].toString(16) + rgb[1].toString(16) + rgb[2].toString(16);
    return null;

This assumes:

  1. You have functions hslToRgb and rgbToHsl.
  2. The parameter colorValue is a string in the form #RRGGBB

Although if we are discussing css there is a syntax for specifying hsl/hsla for IE9/Chrome/Firefox.

AmazonS3 putObject with InputStream length example

adding log4j-1.2.12.jar file has resolved the issue for me

Php, wait 5 seconds before executing an action



Scale an equation to fit exact page width




Multiple HttpPost method in Web API controller


    name: "DefaultApi",
    routeTemplate: "api/{controller}/{action}/{id}",
    defaults: new { id = RouteParameter.Optional }

it's not a RESTful approach anymore, but you can now call your actions by name (rather than let the Web API automatically determine one for you based on the verb) like this:

[POST] /api/VTRouting/TSPRoute

[POST] /api/VTRouting/Route

Contrary to popular belief, there is nothing wrong with this approach, and it's not abusing Web API. You can still leverage on all the awesome features of Web API (delegating handlers, content negotiation, mediatypeformatters and so on) - you just ditch the RESTful approach.

How to keep console window open

Use Console.Readline() at the end .Your code will not close until you close it manually.Since Readline waits for input that needs to be entered for your code hence your console will be open until you type some input.

Rotate image with javascript

CSS can be applied and you will have to set transform-origin correctly to get the applied transformation in the way you want

See the fiddle:

Main code:

/* assuming that the image's height is 70px */

img.rotated {
    transform: rotate(90deg);
    -webkit-transform: rotate(90deg);
    -moz-transform: rotate(90deg);
    -ms-transform: rotate(90deg);

    transform-origin: 35px 35px;
    -webkit-transform-origin: 35px 35px;
    -moz-transform-origin: 35px 35px;
    -ms-transform-origin: 35px 35px;

jQuery and JS:

    .css('transform-origin-x', imgWidth / 2)
    .css('transform-origin-y', imgHeight / 2);

// By calculating the height and width of the image in the load function

// $(img).css('transform-origin', (imgWidth / 2) + ' ' + (imgHeight / 2) );


Divide the image's height by 2. The transform-x and transform-y values should be this value


transform-origin at CSS | MDN

Access restriction: The type 'Application' is not API (restriction on required library rt.jar)

To begin with (and unrelated), instantiating the Application class by yourself does not seem to be its intended use. From what one can read from its source, you are rather expected to use the static instance returned by getApplication().

Now let's get to the error Eclipse reports. I've ran into a similar issue recently: Access restriction: The method ... is not API (restriction on required project). I called the method in question as a method of an object which inherited that method from a super class. All I had to do was to add the package the super class was in to the packages imported by my plugin.

However, there is a lot of different causes for errors based on "restriction on required project/library". Similar to the problem described above, the type you are using might have dependencies to packages that are not exported by the library or might not be exported itself. In that case you can try to track down the missing packages and export them my yourself, as suggested here, or try Access Rules. Other possible scenarios include:

  • Eclipse wants to keep you from using available packages that are not part of the public Java API (solution 1, 2)
  • Dependencies are satisfied by multiple sources, versions are conflicting etc. (solution 1, 2, 3)
  • Eclipse is using a JRE where a JDK is necessary (which might be the case here, from what your errors say; solution) or JRE/JDK version in project build path is not the right one

This ended up as more like a medley of restriction-related issues than an actual answer. But since restriction on required projects is such a versatile error to be reported, the perfect recipe is probably still to be found.

Trying to load local JSON file to show data in a html page using JQuery

As the jQuery API says: "Load JSON-encoded data from the server using a GET HTTP request."

So you cannot load a local file with that function. But as you browse the web then you will see that loading a file from filesystem is really difficult in javascript as the following thread says:

Local file access with javascript

Editing specific line in text file in Python

you can use fileinput to do in place editing

import fileinput
for  line in fileinput.FileInput("myfile", inplace=1):
    if line .....:
         print line

Select datatype of the field in postgres

Pulling data type from information_schema is possible, but not convenient (requires joining several columns with a case statement). Alternatively one can use format_type built-in function to do that, but it works on internal type identifiers that are visible in pg_attribute but not in information_schema. Example

SELECT a.attname as column_name, format_type(a.atttypid, a.atttypmod) AS data_type
FROM pg_attribute a JOIN pg_class b ON a.attrelid = b.relfilenode
WHERE a.attnum > 0 -- hide internal columns
AND NOT a.attisdropped -- hide deleted columns
AND b.oid = 'my_table'::regclass::oid; -- example way to find pg_class entry for a table

Based on

No notification sound when sending notification from firebase in android

adavaced options select advanced options when Write a message, and choose sound activated choose activated

this is My solution

Numpy: Checking if a value is NaT

Very simple and surprisingly fast: (without numpy or pandas)

    str( myDate ) == 'NaT'            # True if myDate is NaT

Ok, it's a little nasty, but given the ambiguity surrounding 'NaT' it does the job nicely.

It's also useful when comparing two dates either of which might be NaT as follows:

   str( date1 ) == str( date1 )       # True
   str( date1 ) == str( NaT )         # False
   str( NaT )   == str( date1 )       # False

wait for it...

   str( NaT )   == str( Nat )         # True    (hooray!)

How can I wait for a thread to finish with .NET?

Try this:

List<Thread> myThreads = new List<Thread>();

foreach (Thread curThread in myThreads)

foreach (Thread curThread in myThreads)

Inline list initialization in VB.NET

Use this syntax for VB.NET 2005/2008 compatibility:

Dim theVar As New List(Of String)(New String() {"one", "two", "three"})

Although the VB.NET 2010 syntax is prettier.

How to update Ruby Version 2.0.0 to the latest version in Mac OSX Yosemite?

You can specify the latest version of ruby by looking at

  1. Fetch the latest version:

    curl -sSL | bash -s stable --ruby

  2. Install it:

    rvm install 2.2

  3. Use it as default:

    rvm use 2.2 --default

Or run the latest command from ruby:

rvm install ruby --latest
rvm use 2.2 --default

AngularJS : automatically detect change in model

In views with {{}} and/or ng-model, Angular is setting up $watch()es for you behind the scenes.

By default $watch compares by reference. If you set the third parameter to $watch to true, Angular will instead "shallow" watch the object for changes. For arrays this means comparing the array items, for object maps this means watching the properties. So this should do what you want:

$scope.$watch('myModel', function() { ... }, true);

Update: Angular v1.2 added a new method for this, `$watchCollection():

$scope.$watchCollection('myModel', function() { ... });

Note that the word "shallow" is used to describe the comparison rather than "deep" because references are not followed -- e.g., if the watched object contains a property value that is a reference to another object, that reference is not followed to compare the other object.

How to give the background-image path in CSS?

There are two basic ways:




I prefer the latter, as it's easier to work with and works from all locations in the site (so useful for inline image paths too).

Mind you, I wouldn't do so much deep nesting of folders. It seems unnecessary and makes life a bit difficult, as you've found.

Windows batch - concatenate multiple text files into one

You can do it using type:

type"C:\<Directory containing files>\*.txt"> merged.txt

all the files in the directory will be appendeded to the file merged.txt.

How to delete all files and folders in a directory?

Call from main

static void Main(string[] args)
   string Filepathe =<Your path>

Add this method

public static void DeleteDirectory(string path)
    if (Directory.Exists(path))
        //Delete all files from the Directory
        foreach (string file in Directory.GetFiles(path))
        //Delete all child Directories
        foreach (string directory in Directory.GetDirectories(path))
        //Delete a Directory

How to copy text programmatically in my Android app?

@FlySwat already gave the correct answer, I am just sharing the complete answer:

Use ClipboardManager.setPrimaryClip ( method:

ClipboardManager clipboard = (ClipboardManager) getSystemService(CLIPBOARD_SERVICE); 
ClipData clip = ClipData.newPlainText("label", "Text to copy");

Where label is a User-visible label for the clip data and text is the actual text in the clip. According to official docs.

It is important to use this import:

import android.content.ClipboardManager;

make html text input field grow as I type?

Here you can try something like this

EDIT: REVISED EXAMPLE (added one new solution)

Code explanation

var jqThis = $('#adjinput'), //object of the input field in jQuery
    fontSize = parseInt( jqThis.css('font-size') ) / 2, //its font-size
    //its min Width (the box won't become smaller than this
    minWidth= parseInt( jqThis.css('min-width') ), 
    //its maxWidth (the box won't become bigger than this)
    maxWidth= parseInt( jqThis.css('max-width') );

jqThis.bind('keydown', function(e){ //on key down
   var newVal = (this.value.length * fontSize); //compute the new width

   if( newVal  > minWidth && newVal <= maxWidth ) //check to see if it is within Min and Max = newVal + 'px'; //update the value.

and the css is pretty straightforward too

    max-width:200px !important;

EDIT: Another solution is to havethe user type what he wants and on blur (focus out), grab the string (in the same font size) place it in a div - count the div's width - and then with a nice animate with a cool easing effect update the input fields width. The only drawback is that the input field will remain "small" while the user types. Or you can add a timeout : ) you can check such a kind of solution on the fiddle above too!

PHP Email sending BCC

You have $headers .= '...'; followed by $headers = '...';; the second line is overwriting the first.

Just put the $headers .= "Bcc: $emailList\r\n"; say after the Content-type line and it should be fine.

On a side note, the To is generally required; mail servers might mark your message as spam otherwise.

$headers  = "From: [email protected]\r\n" .
  "X-Mailer: php\r\n";
$headers .= "MIME-Version: 1.0\r\n";
$headers .= "Content-Type: text/html; charset=ISO-8859-1\r\n";
$headers .= "Bcc: $emailList\r\n";

Returning string from C function

I came across this thread while working on my understanding of Cython. My extension to the original question might be of use to others working at the C / Cython interface. So this is the extension of the original question: how do I return a string from a C function, making it available to Cython & thus to Python?

For those not familiar with it, Cython allows you to statically type Python code that you need to speed up. So the process is, enjoy writing Python :), find its a bit slow somewhere, profile it, calve off a function or two and cythonize them. Wow. Close to C speed (it compiles to C) Fixed. Yay. The other use is importing C functions or libraries into Python as done here.

This will print a string and return the same or another string to Python. There are 3 files, the c file c_hello.c, the cython file sayhello.pyx, and the cython setup file sayhello.pyx. When they are compiled using python build_ext --inplace they generate a shared library file that can be imported into python or ipython and the function sayhello.hello run.


#include <stdio.h>

char *c_hello() {
  char *mystr = "Hello World!\n";
  return mystr;
  // return "this string";  // alterative


cdef extern from "c_hello.c":
    cdef char* c_hello()

def hello():
    return c_hello()

from setuptools import setup
from setuptools.extension import Extension
from Cython.Distutils import build_ext
from Cython.Build import cythonize

ext_modules = cythonize([Extension("sayhello", ["sayhello.pyx"])])

name = 'Hello world app',
cmdclass = {'build_ext': build_ext},
ext_modules = ext_modules

Change Input to Upper Case

Can also do it this way but other ways seem better, this comes in handy if you only need it the once.

onkeyup="this.value = this.value.toUpperCase();"

How to Add Stacktrace or debug Option when Building Android Studio Project

In Android Studios 2.1.1, the command-line Options is under "Build, Execution, Deployment">"Compiler"

enter image description here

How do I remove blue "selected" outline on buttons?

You can remove this by adding !important to your outline.

 outline: none !important;

How do I delete NuGet packages that are not referenced by any project in my solution?

If you have removed package using Uninstall-Package utility and deleted the desired package from package directory under solution (and you are still getting error), just open up the *.csproj file in code editor and remove the tag manually. Like for instance, I wanted to get rid of Nuget package Xamarin.Forms.Alias and I removed these lines from *.csproj file.

Removing nuget package from msbuild script

And finally, don't forget to reload your project once prompted in Visual Studio (after changing project file). I tried it on Visual Studio 2015, but it should work on Visual Studio 2010 and onward too.

Hope this helps.

Java: Check if enum contains a given string?

Use the Apache commons lang3 lib instead

 EnumUtils.isValidEnum(MyEnum.class, myValue)

Get a list of dates between two dates using a function

This does exactly what you want, modified from Will's earlier post. No need for helper tables or loops.

WITH date_range (calc_date) AS (
    SELECT DATEADD(DAY, DATEDIFF(DAY, 0, '2010-01-13') - DATEDIFF(DAY, '2010-01-01', '2010-01-13'), 0)
        UNION ALL SELECT DATEADD(DAY, 1, calc_date)
            FROM date_range
            WHERE DATEADD(DAY, 1, calc_date) <= '2010-01-13')
SELECT calc_date
FROM date_range;

Add comma to numbers every three digits

Very Easy way is to use toLocaleString() function

tot = Rs.1402598 //Result : Rs.1402598

tot.toLocaleString() //Result : Rs.1,402,598

Updated : 23/01/2021

The Variable Should be in number format. Example :

Number(tot).toLocaleString() //Result : Rs.1,402,598

Protect .NET code from reverse engineering?

It's impossible to fully secure an application, sorry.

Entity Framework - Code First - Can't Store List<String>

JSON.NET to the rescue.

You serialize it to JSON to persist in the Database and Deserialize it to reconstitute the .NET collection. This seems to perform better than I expected it to with Entity Framework 6 & SQLite. I know you asked for List<string> but here's an example of an even more complex collection that works just fine.

I tagged the persisted property with [Obsolete] so it would be very obvious to me that "this is not the property you are looking for" in the normal course of coding. The "real" property is tagged with [NotMapped] so Entity framework ignores it.

(unrelated tangent): You could do the same with more complex types but you need to ask yourself did you just make querying that object's properties too hard for yourself? (yes, in my case).

using Newtonsoft.Json;
public Dictionary<string, string> MetaData { get; set; } = new Dictionary<string, string>();

/// <summary> <see cref="MetaData"/> for database persistence. </summary>
[Obsolete("Only for Persistence by EntityFramework")]
public string MetaDataJsonForDb
        return MetaData == null || !MetaData.Any()
                   ? null
                   : JsonConvert.SerializeObject(MetaData);

        if (string.IsNullOrWhiteSpace(value))
           MetaData = JsonConvert.DeserializeObject<Dictionary<string, string>>(value);

How to use a variable in the replacement side of the Perl substitution operator?

I'm not certain on what it is you're trying to achieve. But maybe you can use this:

$var =~ s/^start/foo/;
$var =~ s/end$/bar/;

I.e. just leave the middle alone and replace the start and end.

How to get data from observable in angular2

  (res) => console.log(res),
  (err) => console.log(err),
  () => console.log('done!')

How do I import global modules in Node? I get "Error: Cannot find module <module>"?

You can use require with the path to the global module directory as an argument.


On my mac, I use this:


How to find where your global modules are? --> Where does npm install packages? (Access is denied)

Here's a gotcha that I just discovered - perhaps it might help someone else. If using windows the classes folder must not have encryption enabled! Tomcat doesn't seem to like that. Right click on the classes folder, select "Properties" and then click the "Advanced..." button. Make sure the "Encrypt contents to secure data" checkbox is cleared. Restart Tomcat.

It worked for me so here's hoping it helps someone else, too.

Get a random boolean in python?

I like

 np.random.rand() > .5

How to find if a given key exists in a C++ std::map

Be careful in comparing the find result with the the end like for map 'm' as all answer have done above map::iterator i = m.find("f");

 if (i == m.end())

you should not try and perform any operation such as printing the key or value with iterator i if its equal to m.end() else it will lead to segmentation fault.

Best way to store data locally in .NET (C#)

If you go the binary serialization route, Consider the speed at which a particular member of the datum needs to be accessed. If it is only a small collection, loading the whole file will make sense, but if it will be large, you might also consider an index file.

Tracking Account Properties/fields that are located at a specific address within the file can help you speed up access time, especially if you optimize that index file based on key usage. (possibly even when you write to disk.)

how to call an ASP.NET c# method using javascript

I'm going to go right ahead and offer a solution using jQuery, which means you will need to import the library if you haven't already...

Import the jQuery library in your page mark-up:

<script src="" type="text/javascript"></script>

Then create another *.js script file (I call mine ExecutePageMethod, since that is the only method it is going to expose) and import it:

<script type="text/javascript" src="/ExecutePageMethod.js" ></script>

Within the newly added file, add the following code (I remember pulling this from elsewhere, so someone else deserves credit for it really):

function ExecutePageMethod(page, fn, paramArray, successFn, errorFn) {
    var paramList = '';
    if (paramArray.length > 0) {
        for (var i = 0; i < paramArray.length; i += 2) {
            if (paramList.length > 0) paramList += ',';
            paramList += '"' + paramArray[i] + '":"' + paramArray[i + 1] + '"';
    paramList = '{' + paramList + '}';
        type: "POST",
        url: page + "/" + fn,
        contentType: "application/json; charset=utf-8",
        data: paramList,
        dataType: "json",
        success: successFn,
        error: errorFn

You will then need to augment your .NET page method with the appropriate attributes, as such:

[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public static string MyMethod()
    return "Yay!";

Now, within your page mark-up, within a script block or from another script file, you can call the method, like so:

ExecutePageMethod("PageName.aspx", "MyMethod", [], OnSuccess, OnFailure);

Obviously you will need to implement the OnSuccess and OnFailure methods.

To consume the results, say in the OnSuccess method, you can use the parseJSON method, which, if the results become more complex (in the case or returning an array of types, for instance) this method will parse it into objects:

function OnSuccess(result) {
    var parsedResult = jQuery.parseJSON(result.d);

This ExecutePageMethod code is particularly useful since it it reusable, so rather than having to manage an $.ajax call for each page method you might want to execute, you just need to pass the page, method name and arguments to this method.

JavaScript file upload size validation

No Yes, using the File API in newer browsers. See TJ's answer for details.

If you need to support older browsers as well, you will have to use a Flash-based uploader like SWFUpload or Uploadify to do this.

The SWFUpload Features Demo shows how the file_size_limit setting works.

Note that this (obviously) needs Flash, plus the way it works is a bit different from normal upload forms.

Comparing date part only without comparing time in JavaScript

You can use some arithmetic with the total of ms.

var date = new Date(date1);
date.setHours(0, 0, 0, 0);

var diff = date2.getTime() - date.getTime();
return diff >= 0 && diff < 86400000;

I like this because no updates to the original dates are made and perfom faster than string split and compare.

Hope this help!

Increment counter with loop

You can use varStatus in your c:forEach loop

In your first example you can get the counter to work properly as follows...

<c:forEach var="tableEntity" items='${requestScope.tables}'>
   <c:forEach var="rowEntity" items='${tableEntity.rows}' varStatus="count">            
        my count is ${count.count}

ArrayList - How to modify a member of an object?

Use myList.get(3) to get access to the current object and modify it, assuming instances of Customer have a way to be modified.

Spring Boot REST service exception handling

What about this code ? I use a fallback request mapping to catch 404 errors.

public class ExceptionHandlerController {

    public ModelAndView exceptionHandler(HttpServletRequest request, HttpServletResponse response, Exception ex) {
        //If exception has a ResponseStatus annotation then use its response code
        ResponseStatus responseStatusAnnotation = AnnotationUtils.findAnnotation(ex.getClass(), ResponseStatus.class);

        return buildModelAndViewErrorPage(request, response, ex, responseStatusAnnotation != null ? responseStatusAnnotation.value() : HttpStatus.INTERNAL_SERVER_ERROR);

    public ModelAndView fallbackHandler(HttpServletRequest request, HttpServletResponse response) throws Exception {
        return buildModelAndViewErrorPage(request, response, null, HttpStatus.NOT_FOUND);

    private ModelAndView buildModelAndViewErrorPage(HttpServletRequest request, HttpServletResponse response, Exception ex, HttpStatus httpStatus) {

        ModelAndView mav = new ModelAndView("error.html");
        if (ex != null) {
            mav.addObject("title", ex);
        mav.addObject("content", request.getRequestURL());
        return mav;


Using psql to connect to PostgreSQL in SSL mode

psql -h <host> -p <port> -U <user> -d <db>

and update /var/lib/pgsql/10/data/pg_hba.conf to change the auth method to cert. Check the following link for more information:

Spring Boot: Cannot access REST Controller on localhost (404)

Sometimes spring boot behaves weird. I specified below in application class and it works:


Required attribute HTML5

I just ran into this issue with Safari 5 and it has been an issue with Opera 10 for some time, but I never spent time to fix it. Now I need to fix it and saw your post but no solution yet on how to cancel the form. After much searching I finally found something:

<input type=submit formnovalidate name=cancel value="Cancel">

Works on Safari 5 and Opera 10.

Remove substring from the string

Ruby 2.5+

If your substring is at the beginning of in the end of a string, then Ruby 2.5 has introduced the methods for this:

  • delete_prefix for removing a substring from the beginning of the string
  • delete_suffix for removing a substring from the end of the string

Pointer vs. Reference

If you have a parameter where you may need to indicate the absence of a value, it's common practice to make the parameter a pointer value and pass in NULL.

A better solution in most cases (from a safety perspective) is to use boost::optional. This allows you to pass in optional values by reference and also as a return value.

// Sample method using optional as input parameter
void PrintOptional(const boost::optional<std::string>& optional_str)
    if (optional_str)
       cout << *optional_str << std::endl;
       cout << "(no string)" << std::endl;

// Sample method using optional as return value
boost::optional<int> ReturnOptional(bool return_nothing)
    if (return_nothing)
       return boost::optional<int>();

    return boost::optional<int>(42);

How can I make a ComboBox non-editable in .NET?

for winforms .NET change DropDownStyle to DropDownList from Combobox property

Install-Module : The term 'Install-Module' is not recognized as the name of a cmdlet

Another GUI based option to fix this error is to download the PackageManagement PowerShell Modules (msi installer) from Microsoft website and install the modules.

Once this is installed you will not get "'Install-Module' is not recognized as the name of a cmdlet" error.

How to remove all whitespace from a string?

The function str_squish() from package stringr of tidyverse does the magic!


df <- data.frame(a = c("  aZe  aze s", "wxc  s     aze   "), 
                 b = c("  12    12 ", "34e e4  "), 
                 stringsAsFactors = FALSE)
df <- df %>%
  rowwise() %>%
  mutate_all(funs(str_squish(.))) %>%

# A tibble: 2 x 2
  a         b     
  <chr>     <chr> 
1 aZe aze s 12 12 
2 wxc s aze 34e e4

In Angular, What is 'pathmatch: full' and what effect does it have?

The path-matching strategy, one of 'prefix' or 'full'. Default is 'prefix'.

By default, the router checks URL elements from the left to see if the URL matches a given path, and stops when there is a match. For example, '/team/11/user' matches 'team/:id'.

The path-match strategy 'full' matches against the entire URL. It is important to do this when redirecting empty-path routes. Otherwise, because an empty path is a prefix of any URL, the router would apply the redirect even when navigating to the redirect destination, creating an endless loop.

Source :

Purpose of "%matplotlib inline"

Starting with IPython 5.0 and matplotlib 2.0 you can avoid the use of IPython’s specific magic and use matplotlib.pyplot.ion()/matplotlib.pyplot.ioff() which have the advantages of working outside of IPython as well.

ipython docs

How to combine multiple inline style objects?

Ways of inline styling:

<View style={[, {fontSize: 25}]}>
  <Text>Hello World</Text>

<View style={[,]}>
  <Text>Hello World</Text>

  <View style={{fontSize:10,marginTop:10}}>
  <Text>Hello World</Text>

Creating your own header file in C


#ifndef FOO_H_   /* Include guard */
#define FOO_H_

int foo(int x);  /* An example function declaration */

#endif // FOO_H_


#include "foo.h"  /* Include the header (not strictly necessary here) */

int foo(int x)    /* Function definition */
    return x + 5;


#include <stdio.h>
#include "foo.h"  /* Include the header here, to obtain the function declaration */

int main(void)
    int y = foo(3);  /* Use the function here */
    printf("%d\n", y);
    return 0;

To compile using GCC

gcc -o my_app main.c foo.c

Align image in center and middle within div

#over {
    display: table-cell; 
    vertical-align: middle; 
    text-align: center;
    height: 100px;

Modify height value for your need.

How do I go about adding an image into a java project with eclipse?

If you are doing it in eclipse, there are a few quick notes that if you are hovering your mouse over a class in your script, it will show a focus dialogue that says hit f2 for focus.

for computer apps, use ImageIcon. and for the path say,

ImageIcon thisImage = new ImageIcon("images/youpic.png");

specify the folder( images) then seperate with / and add the name of the pic file.

I hope this is helpful. If someone else posted it, I didn't read through. So...yea.. thought reinforcement.

Cannot install packages inside docker Ubuntu image

I found that mounting a local volume over /tmp can cause permission issues when the "apt-get update" runs, which prevents the package cache from being populated. Hopefully, this isn't something most people do, but it's something else to look for if you see this issue.

How to set image in imageview in android?

use the following code,

    iv.setImageResource(getResources().getIdentifier("apple", "drawable", getPackageName()));

How to rename a directory/folder on GitHub website?

Go to that directory/folder and then click on the setting. In the section of "Repository name" simply rename it.

Do I need to close() both FileReader and BufferedReader?

After checking the source code, I found that for the example:

FileReader fReader = new FileReader(fileName);
BufferedReader bReader = new BufferedReader(fReader);

the close() method on BufferedReader object would call the abstract close() method of Reader class which would ultimately call the implemented method in InputStreamReader class, which then closes the InputStream object.

So, only bReader.close() is sufficient.

Mocking Extension Methods with Moq

I found that I had to discover the inside of the extension method I was trying to mock the input for, and mock what was going on inside the extension.

I viewed using an extension as adding code directly to your method. This meant I needed to mock what happens inside the extension rather than the extension itself.

How can I pass a list as a command-line argument with argparse?


Use the nargs option or the 'append' setting of the action option (depending on how you want the user interface to behave).


parser.add_argument('-l','--list', nargs='+', help='<Required> Set flag', required=True)
# Use like:
# python -l 1234 2345 3456 4567

nargs='+' takes 1 or more arguments, nargs='*' takes zero or more.


parser.add_argument('-l','--list', action='append', help='<Required> Set flag', required=True)
# Use like:
# python -l 1234 -l 2345 -l 3456 -l 4567

With append you provide the option multiple times to build up the list.

Don't use type=list!!! - There is probably no situation where you would want to use type=list with argparse. Ever.

Let's take a look in more detail at some of the different ways one might try to do this, and the end result.

import argparse

parser = argparse.ArgumentParser()

# By default it will fail with multiple arguments.

# Telling the type to be a list will also fail for multiple arguments,
# but give incorrect results for a single argument.
parser.add_argument('--list-type', type=list)

# This will allow you to provide multiple arguments, but you will get
# a list of lists which is not desired.
parser.add_argument('--list-type-nargs', type=list, nargs='+')

# This is the correct way to handle accepting multiple arguments.
# '+' == 1 or more.
# '*' == 0 or more.
# '?' == 0 or 1.
# An int is an explicit number of arguments to accept.
parser.add_argument('--nargs', nargs='+')

# To make the input integers
parser.add_argument('--nargs-int-type', nargs='+', type=int)

# An alternate way to accept multiple inputs, but you must
# provide the flag once per input. Of course, you can use
# type=int here if you want.
parser.add_argument('--append-action', action='append')

# To show the results of the given option to screen.
for _, value in parser.parse_args()._get_kwargs():
    if value is not None:

Here is the output you can expect:

$ python --default 1234 2345 3456 4567
... error: unrecognized arguments: 2345 3456 4567

$ python --list-type 1234 2345 3456 4567
... error: unrecognized arguments: 2345 3456 4567

$ # Quotes won't help here... 
$ python --list-type "1234 2345 3456 4567"
['1', '2', '3', '4', ' ', '2', '3', '4', '5', ' ', '3', '4', '5', '6', ' ', '4', '5', '6', '7']

$ python --list-type-nargs 1234 2345 3456 4567
[['1', '2', '3', '4'], ['2', '3', '4', '5'], ['3', '4', '5', '6'], ['4', '5', '6', '7']]

$ python --nargs 1234 2345 3456 4567
['1234', '2345', '3456', '4567']

$ python --nargs-int-type 1234 2345 3456 4567
[1234, 2345, 3456, 4567]

$ # Negative numbers are handled perfectly fine out of the box.
$ python --nargs-int-type -1234 2345 -3456 4567
[-1234, 2345, -3456, 4567]

$ python --append-action 1234 --append-action 2345 --append-action 3456 --append-action 4567
['1234', '2345', '3456', '4567']


  • Use nargs or action='append'
    • nargs can be more straightforward from a user perspective, but it can be unintuitive if there are positional arguments because argparse can't tell what should be a positional argument and what belongs to the nargs; if you have positional arguments then action='append' may end up being a better choice.
    • The above is only true if nargs is given '*', '+', or '?'. If you provide an integer number (such as 4) then there will be no problem mixing options with nargs and positional arguments because argparse will know exactly how many values to expect for the option.
  • Don't use quotes on the command line1
  • Don't use type=list, as it will return a list of lists
    • This happens because under the hood argparse uses the value of type to coerce each individual given argument you your chosen type, not the aggregate of all arguments.
    • You can use type=int (or whatever) to get a list of ints (or whatever)

1: I don't mean in general.. I mean using quotes to pass a list to argparse is not what you want.

create unique id with javascript

Combining random & date in ms should do the trick with almost no change of collision :

function uniqid(){_x000D_
  return Math.random().toString(16).slice(2)+(new Date()).getTime()+Math.random().toString(16).slice(2);_x000D_

TypeError: got multiple values for argument

I was brought here for a reason not explicitly mentioned in the answers so far, so to save others the trouble:

The error also occurs if the function arguments have changed order - for the same reason as in the accepted answer: the positional arguments clash with the keyword arguments.

In my case it was because the argument order of the Pandas set_axis function changed between 0.20 and 0.22:

0.20: DataFrame.set_axis(axis, labels)
0.22: DataFrame.set_axis(labels, axis=0, inplace=None)

Using the commonly found examples for set_axis results in this confusing error, since when you call:

df.set_axis(['a', 'b', 'c'], axis=1)

prior to 0.22, ['a', 'b', 'c'] is assigned to axis because it's the first argument, and then the positional argument provides "multiple values".

How do I install the ext-curl extension with PHP 7?

Windows users:

Note: Note to Win32 Users In order to enable this module on a Windows environment, libeay32.dll and ssleay32.dll, or, as of OpenSSL 1.1 libcrypto-.dll and libssl-.dll, must be present in your PATH. Also libssh2.dll must be present in your PATH. You don't need libcurl.dll from the cURL site.

Add your C:\wamp\bin\php\php7.1.15 to your PATH

Restart all services

In C#, what's the difference between \n and \r\n?

\n = LF (Line Feed) // Used as a new line character on Unix

\r = CR (Carriage Return) // Used as a new line character on Mac

\r\n = CR + LF // Used as a new line character on Windows

(char)13 = \r = CR

Environment.NewLine = any of the above code based on the operating system

// .NET provides the Environment class which provides many data based on operating systems, so if the application is built on Windows, and you use CR + LF ("\n\r" instead of Environment.NewLine) as the new line character in your strings, and then Microsoft creates a VM for running .NET applications in Unix, then there will be problem. So, you should always use Environment.NewLine when you want a new line character. Now you need not to care about the operating system.

IPython Notebook save location

  1. Based on my experience, if you use "ipython.exe" in python-2.7.5/Scripts from other directory, as typing at the comamnd prompt as ipython notebook, *.ipynb files will be loaded and saved in the current directory. ("notebook" is just a comamnd line parameter) I think the "ipython notebook.exe" in Winpython top directory is not relevant for your request. As for me, I added the ipython.exe directory to the Path only.
  2. If you want to make your profile in user directory, see below:

JQuery datepicker language

You need to do something like this,

 $.datepicker.regional['fr'] = {clearText: 'Effacer', clearStatus: '',
    closeText: 'Fermer', closeStatus: 'Fermer sans modifier',
    prevText: '<Préc', prevStatus: 'Voir le mois précédent',
    nextText: 'Suiv>', nextStatus: 'Voir le mois suivant',
    currentText: 'Courant', currentStatus: 'Voir le mois courant',
    monthNames: ['Janvier','Février','Mars','Avril','Mai','Juin',
    monthNamesShort: ['Jan','Fév','Mar','Avr','Mai','Jun',
    monthStatus: 'Voir un autre mois', yearStatus: 'Voir un autre année',
    weekHeader: 'Sm', weekStatus: '',
    dayNames: ['Dimanche','Lundi','Mardi','Mercredi','Jeudi','Vendredi','Samedi'],
    dayNamesShort: ['Dim','Lun','Mar','Mer','Jeu','Ven','Sam'],
    dayNamesMin: ['Di','Lu','Ma','Me','Je','Ve','Sa'],
    dayStatus: 'Utiliser DD comme premier jour de la semaine', dateStatus: 'Choisir le DD, MM d',
    dateFormat: 'dd/mm/yy', firstDay: 0, 
    initStatus: 'Choisir la date', isRTL: false};

for sv data follow the following link

Printing string variable in Java

You could also use BufferedReader:


public class TestApplication {
   public static void main (String[] args) {
      System.out.print("Enter a password: ");
      BufferedReader br = new BufferedReader(new InputStreamReader(;
      String password = null;
      try {
         password = br.readLine();
      } catch (IOException e) {
         System.out.println("IO error trying to read your password!");
      System.out.println("Successfully read your password.");

Delete all but the most recent X files in bash

Ignoring newlines is ignoring security and good coding. wnoise had the only good answer. Here is a variation on his that puts the filenames in an array $x

while IFS= read -rd ''; do 
    x+=("${REPLY#* }"); 
done < <(find . -maxdepth 1 -printf '%T@ %p\0' | sort -r -z -n )

Can't bind to 'routerLink' since it isn't a known property

In my case I just need to import my newly created component to RouterModule

{path: 'newPath', component: newComponent}

Then in your app.module import the router and configure the routes:

import { RouterModule } from '@angular/router';

imports: [
            {path: '', component: DashboardComponent},
            {path: 'dashboard', component: DashboardComponent},
            {path: 'newPath', component: newComponent}

Hope this helps to some one !!!

PHP mPDF save file as PDF

Try this:



D - means Download
F - means File-save only