Programs & Examples On #Add filter

How to convert datetime format to date format in crystal report using C#?

In selection formula try this

Date(Year({datetimefield}), Month({datetimefield}), Day({datetimefield}))

browser.msie error after update to jQuery 1.9.1

$.browser was deprecated in version 1.3 and removed in 1.9

You can verify this by viewing the documentation.

Multiple lines of text in UILabel

In this function pass string that you want to assign in label and pass font size in place of self.activityFont and pass label width in place of 235, now you get label height according to your string. it will work fine.

-(float)calculateLabelStringHeight:(NSString *)answer
    CGRect textRect = [answer boundingRectWithSize: CGSizeMake(235, 10000000) options:NSStringDrawingUsesLineFragmentOrigin attributes:@{NSFontAttributeName:self.activityFont} context:nil];
    return textRect.size.height;


How to Set Opacity (Alpha) for View in Android

For a view you can set opacity by the following.


The property view.setAlpha(int) is deprecated for the API version greater than 11. Henceforth, property like .setAlpha(0.5f) is used.

How do I filter an array with AngularJS and use a property of the filtered object as the ng-model attribute?

You can use the "filter" filter in your controller to get all the "C" grades. Getting the first element of the result array will give you the title of the subject that has grade "C".

$scope.gradeC = $filter('filter')($scope.results.subjects, {grade: 'C'})[0];

The same with plain ES6:

$scope.gradeC = $scope.results.subjects.filter((subject) => subject.grade === 'C')[0]

How to implement Android Pull-to-Refresh

To get the latest Lollipop Pull-To Refresh:

  1. Download the latest Lollipop SDK and Extras/Android support library
  2. Set Project's Build Target to Android 5.0 (otherwise support package can have errors with resources)
  3. Update your libs/android-support-v4.jar to 21st version
  4. Use plus

Detailed guide could be found here:

Plus for ListView I recommend to read about canChildScrollUp() in the comments ;)

Getting file size in Python?

Use os.path.getsize(path) which will

Return the size, in bytes, of path. Raise OSError if the file does not exist or is inaccessible.

import os

Or use os.stat(path).st_size

import os

Or use Path(path).stat().st_size (Python 3.4+)

from pathlib import Path

How can I check if my Element ID has focus?

Write below code in script and also add jQuery library

var getElement = document.getElementById('myID');

if (document.activeElement === getElement) {
        $(document).keydown(function(event) {
            if (event.which === 40) {
                console.log('keydown pressed')

Thank you...

How do I turn off Unicode in a VC++ project?

Have you tried: Project Properties - General - Project Defaults - Character Set?

See answers in this question for the differences between "Use Multi-Byte Character Set" and "Not Set" options: About the "Character set" option in visual studio 2010

Adding Google Play services version to your app's manifest?

From here

You should be referencing a copy of the library that you copied to your development workspace—you should not reference the library directly from the Android SDK directory.

I faced this error because I referenced the original copy from SDK directory. Make sure that you first copy the library to android workspace and only reference it. In eclipse you can do it by checking "Copy projects into workspace" while importing the project.

How to send email to multiple recipients using python smtplib?

I tried the below and it worked like a charm :)

rec_list =  ['[email protected]', '[email protected]']
rec =  ', '.join(rec_list)

msg['To'] = rec

send_out = smtplib.SMTP('localhost')
send_out.sendmail(me, rec_list, msg.as_string())

Can linux cat command be used for writing text to file?

simply pipeline echo with cat

For example

echo write something to file.txt | cat > file.txt

Is it possible to create a remote repo on GitHub from the CLI without opening browser?

Nope, you have to open a browser atleast once to create your username on GitHub, once created, you can leverage GitHub API to create repositories from command line, following below command:

curl -u 'github-username' -d '{"name":"repo-name"}'

For example:

curl -u 'arpitaggarwal' -d '{"name":"command-line-repo"}'

Finding the layers and layer sizes for each Docker image

They have a very good answer here:

Just run below images:

docker run --rm -v /var/run/docker.sock:/var/run/docker.sock nate/dockviz images -t

Step out of current function with GDB

You can use the finish command.

finish: Continue running until just after function in the selected stack frame returns. Print the returned value (if any). This command can be abbreviated as fin.

(See 5.2 Continuing and Stepping.)

How do I disable "missing docstring" warnings at a file-level in Pylint?

Edit file "C:\Users\Your User\AppData\Roaming\Code\User\settings.json" and add these python.linting.pylintArgs lines at the end as shown below:

    "team.showWelcomeMessage": false,
    "python.dataScience.sendSelectionToInteractiveWindow": true,
    "git.enableSmartCommit": true,
    "powershell.codeFormatting.useCorrectCasing": true,
    "files.autoSave": "onWindowChange",
    "python.linting.pylintArgs": [

Error: The type exists in both directories


Normally, when this happen locally, i clean all the aspnet temp folder. But recently it was happing when i published my website in Azure. So "clean temp aspnet folder" was not a solution.

After searching on the internet, i founded this:

Clear Temp ASP.NET files from Azure Web Site

It works for me!

How to select a div element in the code-behind page?

@CarlosLanderas is correct depending on where you've placed the DIV control. The DIV by the way is not technically an ASP control, which is why you cannot find it directly like other controls. But the best way around this is to turn it into an ASP control.

Use asp:Panel instead. It is rendered into a <div> tag anyway...

<asp:Panel id="divSubmitted" runat="server" style="text-align:center" visible="false">
   <asp:Label ID="labSubmitted" runat="server" Text="Roll Call Submitted"></asp:Label>

And in code behind, simply find the Panel control as per normal...

Panel DivCtl1 = (Panel)gvRollCall.FooterRow.FindControl("divSubmitted");
if (DivCtl1 != null)
    DivCtl1.Visible = true;

Please note that I've used FooterRow, as my "psuedo div" is inside the footer row of a Gridview control.

Good coding!

How to store decimal values in SQL Server?

You should use is as follows:


m is the number of total digits your decimal can have.

a is the max number of digits you can have after the decimal point. has descriptions for all the datatypes.


Simple query without partition clause:

    RANK() over(order by sal desc) as Rank,
    DENSE_RANK() over(order by sal desc) as DenseRank,
    ROW_NUMBER() over(order by sal desc) as RowNumber
from employee 


    sal     |Rank   |DenseRank  |RowNumber
    5000    |1      |1          |1
    3000    |2      |2          |2
    3000    |2      |2          |3
    2975    |4      |3          |4
    2850    |5      |4          |5

How can I exclude one word with grep?

Invert match using grep -v:

grep -v "unwanted word" file pattern

How to change the color of header bar and address bar in newest Chrome version on Lollipop?

Found the solution after some searching.

You need to add a <meta> tag in your <head> containing name="theme-color", with your HEX code as the content value. For example:

<meta name="theme-color" content="#999999" />


If the android device has native dark-mode enabled, then this meta tag is ignored.

Chrome for Android does not use the color on devices with native dark-mode enabled.


Format telephone and credit card numbers in AngularJS

I modified the code to output phone in this format Value: +38 (095) 411-22-23 Here you can check it enter link description here

    var myApp = angular.module('myApp', []);

myApp.controller('MyCtrl', function($scope) {

myApp.directive('phoneInput', function($filter, $browser) {
    return {
        require: 'ngModel',
        link: function($scope, $element, $attrs, ngModelCtrl) {
            var listener = function() {
                var value = $element.val().replace(/[^0-9]/g, '');
                $element.val($filter('tel')(value, false));

            // This runs when we update the text field
            ngModelCtrl.$parsers.push(function(viewValue) {
                return viewValue.replace(/[^0-9]/g, '').slice(0,12);

            // This runs when the model gets updated on the scope directly and keeps our view in sync
            ngModelCtrl.$render = function() {
                $element.val($filter('tel')(ngModelCtrl.$viewValue, false));

            $element.bind('change', listener);
            $element.bind('keydown', function(event) {
                var key = event.keyCode;
                // If the keys include the CTRL, SHIFT, ALT, or META keys, or the arrow keys, do nothing.
                // This lets us support copy and paste too
                if (key == 91 || (15 < key && key < 19) || (37 <= key && key <= 40)){
                $browser.defer(listener); // Have to do this or changes don't get picked up properly

            $element.bind('paste cut', function() {

myApp.filter('tel', function () {
    return function (tel) {
        if (!tel) { return ''; }

        var value = tel.toString().trim().replace(/^\+/, '');

        if (value.match(/[^0-9]/)) {
            return tel;

        var country, city, num1, num2, num3;

        switch (value.length) {
            case 1:
            case 2:
            case 3:
                city = value;

                country = value.slice(0, 2);
                city = value.slice(2, 5);
                num1 = value.slice(5,8);
                num2 = value.slice(8,10);
                num3 = value.slice(10,12);            

        if(country && city && num1 && num2 && num3){
            return ("+" + country+" (" + city + ") " + num1 +"-" + num2 + "-" + num3).trim();
        else if(country && city && num1 && num2) {
            return ("+" + country+" (" + city + ") " + num1 +"-" + num2).trim();
        }else if(country && city && num1) {
            return ("+" + country+" (" + city + ") " + num1).trim();
        }else if(country && city) {
            return ("+" + country+" (" + city ).trim();
        }else if(country ) {
            return ("+" + country).trim();


How to Scroll Down - JQuery

$('.btnMedio').click(function(event) {
    // Preventing default action of the event
    // Getting the height of the document
    var n = $(document).height();
    $('html, body').animate({ scrollTop: n }, 50);
//                                       |    |
//                                       |    --- duration (milliseconds) 
//                                       ---- distance from the top

Skip over a value in the range function in python

for i in range(0, 101):
if i != 50:
    do sth

Last Key in Python Dictionary

In python 3.6 I got the value of last key from the following code


Rotating x axis labels in R for barplot

You may use

par(las=2) # make label text perpendicular to axis

It is written here:

Text border using css (border around text)

Use multiple text shadows:

text-shadow: 2px 0 0 #fff, -2px 0 0 #fff, 0 2px 0 #fff, 0 -2px 0 #fff, 1px 1px #fff, -1px -1px 0 #fff, 1px -1px 0 #fff, -1px 1px 0 #fff;

enter image description here

body {_x000D_
  font-family: sans-serif;_x000D_
  background: #222;_x000D_
  color: darkred;_x000D_
h1 {_x000D_
  text-shadow: 2px 0 0 #fff, -2px 0 0 #fff, 0 2px 0 #fff, 0 -2px 0 #fff, 1px 1px #fff, -1px -1px 0 #fff, 1px -1px 0 #fff, -1px 1px 0 #fff;_x000D_

Alternatively, you could use text stroke, which only works in webkit:

-webkit-text-stroke-width: 2px;
-webkit-text-stroke-color: #fff;

enter image description here

body {_x000D_
  font-family: sans-serif;_x000D_
  background: #222;_x000D_
  color: darkred;_x000D_
h1 {_x000D_
  -webkit-text-stroke-width: 2px;_x000D_
-webkit-text-stroke-color: #fff;_x000D_

Also read more as CSS-Tricks.

Change GitHub Account username

Yes, it's possible. But first read, "What happens when I change my username?"

To change your username, click your profile picture in the top right corner, then click Settings. On the left side, click Account. Then click Change username.

gem install: Failed to build gem native extension (can't find header files)

If you have gem installed and ruby and not able to install rails, then install ruby dev lib.

sudo apt-get install ruby-dev

It works for me. I have tried the different solution.

Are there any worse sorting algorithms than Bogosort (a.k.a Monkey Sort)?

Here's 2 sorts I came up with my roommate in college

1) Check the order 2) Maybe a miracle happened, go to 1


1) check if it is in order, if not 2) put each element into a packet and bounce it off a distant server back to yourself. Some of those packets will return in a different order, so go to 1

:before and background-image... should it work?

@michi; define height in your before pseudo class


    width: 16px;
    content: " ";
    background-image: url(/img/border-left3.png);
    position: absolute;
    left: -16px;
    top: -6px;

Dynamic instantiation from string name of a class in dynamically imported module?

You can use getattr

getattr(module, class_name)

to access the class. More complete code:

module = __import__(module_name)
class_ = getattr(module, class_name)
instance = class_()

As mentioned below, we may use importlib

import importlib
module = importlib.import_module(module_name)
class_ = getattr(module, class_name)
instance = class_()

Java: How to stop thread?

We don't stop or kill a thread rather we do Thread.currentThread().isInterrupted().

public class Task1 implements Runnable {
    public void run() {
            while (!Thread.currentThread().isInterrupted()) {

in main we will do like this:

Thread t1 = new Thread(new Task1());

Execute CMD command from code

You can use this to work cmd in C#:

ProcessStartInfo proStart = new ProcessStartInfo();
Process pro = new Process();
proStart.FileName = "cmd.exe";
proStart.WorkingDirectory = @"D:\...";
string arg = "/c your_argument";
proStart.Arguments = arg;
proStart.WindowStyle = ProcessWindowStyle.Hidden;
pro.StartInfo = pro;

Don't forget to write /c before your argument !!

Error in <my code> : object of type 'closure' is not subsettable

You don't define the vector, url, before trying to subset it. url is also a function in the base package, so url[i] is attempting to subset that function... which doesn't make sense.

You probably defined url in your prior R session, but forgot to copy that code to your script.

Create Test Class in IntelliJ

Use the menu selection Navigate > Test




Ctrl + Shift + T


? + Shift + T

Iterating through a JSON object

Your loading of the JSON data is a little fragile. Instead of:

json_raw= raw.readlines()
json_object = json.loads(json_raw[0])

you should really just do:

json_object = json.load(raw)

You shouldn't think of what you get as a "JSON object". What you have is a list. The list contains two dicts. The dicts contain various key/value pairs, all strings. When you do json_object[0], you're asking for the first dict in the list. When you iterate over that, with for song in json_object[0]:, you iterate over the keys of the dict. Because that's what you get when you iterate over the dict. If you want to access the value associated with the key in that dict, you would use, for example, json_object[0][song].

None of this is specific to JSON. It's just basic Python types, with their basic operations as covered in any tutorial.

How to uninstall an older PHP version from centOS7

Subscribing to the IUS Community Project Repository

cd ~
curl '' -o

Run the script:

sudo bash

Upgrading mod_php with Apache

This section describes the upgrade process for a system using Apache as the web server and mod_php to execute PHP code. If, instead, you are running Nginx and PHP-FPM, skip ahead to the next section.

Begin by removing existing PHP packages. Press y and hit Enter to continue when prompted.

sudo yum remove php-cli mod_php php-common

Install the new PHP 7 packages from IUS. Again, press y and Enter when prompted.

sudo yum install mod_php70u php70u-cli php70u-mysqlnd

Finally, restart Apache to load the new version of mod_php:

sudo apachectl restart

You can check on the status of Apache, which is managed by the httpd systemd unit, using systemctl:

systemctl status httpd

TypeError: Router.use() requires middleware function but got a Object

Check your all these file:

var users = require('./routes/users');

var Users = require('./models/user');
var Items = require('./models/item');

Save properly, In my case, one file was missed and throwing the same error

Creating CSS Global Variables : Stylesheet theme management

You will either need LESS or SASS for the same..

But here is another alternative which I believe will work out in CSS3..

Example :

 :root {
    -webkit-var-beautifulColor: rgba(255,40,100, 0.8);
    -moz-var-beautifulColor: rgba(255,40,100, 0.8);
    -ms-var-beautifulColor: rgba(255,40,100, 0.8);
    -o-var-beautifulColor: rgba(255,40,100, 0.8);
    var-beautifulColor: rgba(255,40,100, 0.8);
  .example1 h1 {
    color: -webkit-var(beautifulColor);
    color: -moz-var(beautifulColor);
    color: -ms-var(beautifulColor);
    color: -o-var(beautifulColor);
    color: var(beautifulColor);

.htaccess deny from all

A little alternative to @gasp´s answer is to simply put the actual domain name you are running it from. Docs:

In the following example, there is no authentication and all hosts in the domain are allowed access; all other hosts are denied access.

Apache 2.2 configuration:

Order Deny,Allow
Deny from all
Allow from

Apache 2.4 configuration:

Require host

Convert datatable to JSON in C#

I have simple function to convert datatable to json string.

I have used Newtonsoft to generate string. I don't use Newtonsoft to totaly serialize Datatable. Be careful about this.

Maybe this can be useful.

 private string DataTableToJson(DataTable dt) {
  if (dt == null) {
   return "[]";
  if (dt.Rows.Count < 1) {
   return "[]";

  JArray array = new JArray();
  foreach(DataRow dr in dt.Rows) {
   JObject item = new JObject();
   foreach(DataColumn col in dt.Columns) {
    item.Add(col.ColumnName, dr[col.ColumnName]?.ToString());

  return array.ToString(Newtonsoft.Json.Formatting.Indented);

Vue.js data-bind style backgroundImage not working

The issue is that the value for backgroundImage needs to be a string like this:

<div class="circular" v-bind:style="{ backgroundImage: 'url(' + image + ')' }"></div>

Here's a simplified fiddle that's working:

Re: the comment below about kebab-case, this is how you can do that:

<div class="circular" v-bind:style="{ 'background-image': 'url(' + image + ')' }"></div>

In other words, the value for v-bind:style is just a plain Javascript object and follows the same rules.

UPDATE: One other note about why you may have trouble getting this to work.

You should make sure your image value is quoted so that the end resulting string is:


Otherwise, if your image URL has special characters in it (such as whitespace or parentheses) the browser may not apply it properly. In Javascript, the assignment would look like:

this.image = "'some/url/path/to/image.jpeg'"


this.image = "'" + myUrl + "'"

Technically, this could be done in the template, but the escaping required to keep it valid HTML isn't worth it.

More info here: Is quoting the value of url() really necessary?

htaccess redirect all pages to single page

Add this for pages not currently on your site...

ErrorDocument 404

Along with your Redirect 301 / that should cover all the bases...

Good luck!

Add CSS3 transition expand/collapse

This is my solution that adjusts the height automatically:

function growDiv() {_x000D_
  var growDiv = document.getElementById('grow');_x000D_
  if (growDiv.clientHeight) {_x000D_ = 0;_x000D_
  } else {_x000D_
    var wrapper = document.querySelector('.measuringWrapper');_x000D_ = wrapper.clientHeight + "px";_x000D_
  document.getElementById("more-button").value = document.getElementById("more-button").value == 'Read more' ? 'Read less' : 'Read more';_x000D_
#more-button {_x000D_
  border-style: none;_x000D_
  background: none;_x000D_
  font: 16px Serif;_x000D_
  color: blue;_x000D_
  margin: 0 0 10px 0;_x000D_
#grow input:checked {_x000D_
  color: red;_x000D_
#more-button:hover {_x000D_
  color: black;_x000D_
#grow {_x000D_
  -moz-transition: height .5s;_x000D_
  -ms-transition: height .5s;_x000D_
  -o-transition: height .5s;_x000D_
  -webkit-transition: height .5s;_x000D_
  transition: height .5s;_x000D_
  height: 0;_x000D_
  overflow: hidden;_x000D_
<input type="button" onclick="growDiv()" value="Read more" id="more-button">_x000D_
<div id='grow'>_x000D_
  <div class='measuringWrapper'>_x000D_
    <div class="text">Here is some more text: Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum vitae urna nulla. Vivamus a purus mi. In hac habitasse platea dictumst. In ac tempor quam. Vestibulum eleifend vehicula ligula, et cursus nisl gravida sit_x000D_
      amet. Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas.</div>_x000D_

I used the workaround that r3bel posted: Can you use CSS3 to transition from height:0 to the variable height of content?

Hidden property of a button in HTML

<script src=""></script>

function showButtons () { $('#b1, #b2, #b3').show(); }

<style type="text/css">
#b1, #b2, #b3 {
display: none;


<a href="#" onclick="showButtons();">Show me the money!</a>

<input type="submit" id="b1" value="B1" />
<input type="submit" id="b2" value="B2"/>
<input type="submit" id="b3" value="B3" />


Getting URL

You can use api to create facebook short urls find the documentation here

The server encountered an internal error that prevented it from fulfilling this request - in servlet 3.0

In here:

    if (ValidationUtils.isNullOrEmpty(lastName)) {
    if (!ValidationUtils.isEmailValid(email)) {

you check for null or empty value on lastname, but in isEmailValid you don't check for empty value. Something like this should do

    if (ValidationUtils.isNullOrEmpty(email) || !ValidationUtils.isEmailValid(email)) {

or better yet, fix your ValidationUtils.isEmailValid() to cope with null email values. It shouldn't crash, it should just return false.

Free ASP.Net and/or CSS Themes

Microsoft hired one fo the kids from A List Apart to whip some out. The .Net projects are free of charge for download.

How to set recurring schedule for xlsm file using Windows Task Scheduler

I referred a blog by Kim for doing this and its working fine for me. See the blog

The automated execution of macro can be accomplished with the help of a VB Script file which is being invoked by Windows Task Scheduler at specified times.

Remember to replace 'YourWorkbook' with the name of the workbook you want to open and replace 'YourMacro' with the name of the macro you want to run.

See the VB Script File (just named it RunExcel.VBS):

    ' Create a WshShell to get the current directory
Dim WshShell
Set WshShell = CreateObject("WScript.Shell")

' Create an Excel instance
Dim myExcelWorker
Set myExcelWorker = CreateObject("Excel.Application") 

' Disable Excel UI elements
myExcelWorker.DisplayAlerts = False
myExcelWorker.AskToUpdateLinks = False
myExcelWorker.AlertBeforeOverwriting = False
myExcelWorker.FeatureInstall = msoFeatureInstallNone

' Tell Excel what the current working directory is 
' (otherwise it can't find the files)
Dim strSaveDefaultPath
Dim strPath
strSaveDefaultPath = myExcelWorker.DefaultFilePath
strPath = WshShell.CurrentDirectory
myExcelWorker.DefaultFilePath = strPath

' Open the Workbook specified on the command-line 
Dim oWorkBook
Dim strWorkerWB
strWorkerWB = strPath & "\YourWorkbook.xls"

Set oWorkBook = myExcelWorker.Workbooks.Open(strWorkerWB)

' Build the macro name with the full path to the workbook
Dim strMacroName
strMacroName = "'" & strPath & "\YourWorkbook" & "!Sheet1.YourMacro"
on error resume next 
   ' Run the calculation macro
   myExcelWorker.Run strMacroName
   if err.number <> 0 Then
      ' Error occurred - just close it down.
   End If
on error goto 0 


myExcelWorker.DefaultFilePath = strSaveDefaultPath

' Clean up and shut down
Set oWorkBook = Nothing

' Don’t Quit() Excel if there are other Excel instances 
' running, Quit() will shut those down also
if myExcelWorker.Workbooks.Count = 0 Then
End If

Set myExcelWorker = Nothing
Set WshShell = Nothing

You can test this VB Script from command prompt:

>> cscript.exe RunExcel.VBS

Once you have the VB Script file and workbook tested so that it does what you want, you can then use Microsoft Task Scheduler (Control Panel-> Administrative Tools--> Task Scheduler) to execute ‘cscript.exe RunExcel.vbs’ automatically for you.

Please note the path of the macro should be in correct format and inside single quotes like:

strMacroName = "'" & strPath & "\YourWorkBook.xlsm'" & 

scp from Linux to Windows

As @Hesham Eraqi suggested, it worked for me in this way (transfering from Ubuntu to Windows (I tried to add a comment in that answer but because of reputation, I couldn't)):

pscp -v -r -P 53670 [email protected]:/data/genetic_map/sample/P2_283/* \\Desktop-mojbd3n\d\cc_01-1940_data\


-v: show verbose messages.
-r: copy directories recursively.
-P: connect to specified port.
53670: the port number to connect the Ubuntu server.
\\Desktop-mojbd3n\d\genetic_map_data\: I needed to transfer to an external HDD, thus I had to give permissions of sharing to this device.

How to restart service using command prompt?

You could create a .bat-file with following content:

net stop "my service name"
net start "my service name"

How can I determine browser window size on server side C#

There is a solution to solve page_onload problem (can't get size until page load complete) : Create a userControl :

<%@ Control Language="VB" AutoEventWireup="false" CodeFile="ClientSizeDetector.ascx.vb"    Inherits="Project_UserControls_ClientSizeDetector" %>
<%If (IsFirstTime) Then%>
<script type="text/javascript">
var pageURL =\?/) > 0 ? "&" : "?";
window.location.href = window.location.href + pageURL + "clientHeight=" + window.innerHeight + "&clientWidth=" + window.innerWidth;
<%End If%>

Code behind :

 Private _isFirstTime As Boolean = False
 Private _clientWidth As Integer = 0
 Private _clientHeight As Integer = 0

 Public Property ClientWidth() As Integer
        Return _clientWidth
    End Get
    Set(value As Integer)
        _clientWidth = value
    End Set
End Property

Public Property ClientHeight() As Integer
        Return _clientHeight
    End Get
    Set(value As Integer)
        _clientHeight = value
    End Set
End Property

public Property IsFirstTime() As Boolean 
        Return _isFirstTime
    End Get
    Set(value As Boolean)
        _isFirstTime = value
    End Set
End Property

Protected Overrides Sub OnInit(e As EventArgs)

    If (String.IsNullOrEmpty(Request.QueryString("clientHeight")) Or String.IsNullOrEmpty(Request.QueryString("clientWidth"))) Then
        Me._isFirstTime = True
        Integer.TryParse(Request.QueryString("clientHeight").ToString(), ClientHeight)
        Integer.TryParse(Request.QueryString("clientWidth").ToString(), ClientWidth)
        Me._isFirstTime = False
    End If
End Sub

So after, you can call your control properties

Sort array of objects by object fields

if you're using php oop you might need to change to:

public static function cmp($a, $b) 
    return strcmp($a->name, $b->name);

//in this case FUNCTION_NAME would be cmp
usort($your_data, array('YOUR_CLASS_NAME','FUNCTION_NAME')); 

Slidedown and slideup layout with animation

Create two animation xml under res/anim folder


<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="" >

    android:toYDelta="100%" />


<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="" >

    android:toYDelta="0" />

Load animation Like bellow Code and start animation when you want According to your Requirement

//Load animation 
Animation slide_down = AnimationUtils.loadAnimation(getApplicationContext(),

Animation slide_up = AnimationUtils.loadAnimation(getApplicationContext(),

// Start animation

error: (-215) !empty() in function detectMultiScale

I faced a similar issue. It seems correcting the path to XML makes this error to go away.

How can I add or update a query string parameter?

It's so simple with URLSearchParams, supported in all modern browsers (caniuse).

let p = new URLSearchParams();
p.set("foo", "bar");
p.set("name", "Jack & Jill?");
console.log("" + p.toString());

If you want to modify the existing URL, construct the object like this: new URLSearchParams( and assign the string to

SVN how to resolve new tree conflicts when file is added on two branches

I found a post suggesting a solution for that. It's about to run:

svn resolve --accept working <YourPath>

which will claim the local version files as OK.
You can run it for single file or entire project catalogues.

What is the best way to ensure only one instance of a Bash script is running?

I found a pretty simple way to handle "one copy of script per system". It doesn't allow me to run multiple copies of the script from many accounts though (on standard Linux that is).


At the beginning of script, I gave:

pidof -s -o '%PPID' -x $( basename $0 ) > /dev/null 2>&1 && exit

Apparently pidof works great in a way that:

  • it doesn't have limit on program name like ps -C ...
  • it doesn't require me to do grep -v grep ( or anything similar )

And it doesn't rely on lockfiles, which for me is a big win, because relaying on them means you have to add handling of stale lockfiles - which is not really complicated, but if it can be avoided - why not?

As for checking with "one copy of script per running user", i wrote this, but I'm not overly happy with it:

    pidof -s -o '%PPID' -x $( basename $0 ) | tr ' ' '\n'
    ps xo pid= | tr -cd '[0-9\n]'
) | sort | uniq -d

and then I check its output - if it's empty - there are no copies of the script from same user.

What is the difference between char * const and const char *?

Two rules

  1. If const is between char and *, it will affect the left one.
  2. If const is not between char and *, it will affect the nearest one.


  1. char const *. This is a pointer points to a constant char.
  2. char * const. This is a constant pointer points to a char.

Could not read JSON: Can not deserialize instance of hello.Country[] out of START_OBJECT token

Another solution:

public class CountryInfoResponse {
  private List<Object> geonames;

Usage of a generic Object-List solved my problem, as there were other Datatypes like Boolean too.

Regular expression for extracting tag attributes

PHP (PCRE) and Python

Simple attribute extraction (See it working):


Or with tag opening / closure verification, tag name retrieval and comment escaping. This expression foresees unquoted / quoted, single / double quotes, escaped quotes inside attributes, spaces around equals signs, different number of attributes, check only for attributes inside tags, and manage different quotes within an attribute value. (See it working):


(Works better with the "gisx" flags.)


As Javascript regular expressions don't support look-behinds, it won't support most features of the previous expressions I propose. But in case it might fit someone's needs, you could try this version. (See it working).


Why do I get a "permission denied" error while installing a gem?

I think the problem happened when you use rbenv. Try the below commands to fix it.

rbenv shell {rb_version}
rbenv global {rb_version}
rbenv local {rb_version}

How to check if a "lateinit" variable has been initialized?

To check if a lateinit var were initialised or not use a .isInitialized on the reference to that property:

if (foo::bar.isInitialized) {

This checking is only available for the properties that are accessible lexically, i.e. declared in the same type or in one of the outer types, or at top level in the same file.

matrix multiplication algorithm time complexity

The standard way of multiplying an m-by-n matrix by an n-by-p matrix has complexity O(mnp). If all of those are "n" to you, it's O(n^3), not O(n^2). EDIT: it will not be O(n^2) in the general case. But there are faster algorithms for particular types of matrices -- if you know more you may be able to do better.

What's the difference between Cache-Control: max-age=0 and no-cache?

By the way, it's worth noting that some mobile devices, particularly Apple products like iPhone/iPad completely ignore headers like no-cache, no-store, Expires: 0, or whatever else you may try to force them to not re-use expired form pages.

This has caused us no end of headaches as we try to get the issue of a user's iPad say, being left asleep on a page they have reached through a form process, say step 2 of 3, and then the device totally ignores the store/cache directives, and as far as I can tell, simply takes what is a virtual snapshot of the page from its last state, that is, ignoring what it was told explicitly, and, not only that, taking a page that should not be stored, and storing it without actually checking it again, which leads to all kinds of strange Session issues, among other things.

I'm just adding this in case someone comes along and can't figure out why they are getting session errors with particularly iphones and ipads, which seem by far to be the worst offenders in this area.

I've done fairly extensive debugger testing with this issue, and this is my conclusion, the devices ignore these directives completely.

Even in regular use, I've found that some mobiles also totally fail to check for new versions via say, Expires: 0 then checking last modified dates to determine if it should get a new one.

It simply doesn't happen, so what I was forced to do was add query strings to the css/js files I needed to force updates on, which tricks the stupid mobile devices into thinking it's a file it does not have, like: my.css?v=1, then v=2 for a css/js update. This largely works.

User browsers also, by the way, if left to their defaults, as of 2016, as I continuously discover (we do a LOT of changes and updates to our site) also fail to check for last modified dates on such files, but the query string method fixes that issue. This is something I've noticed with clients and office people who tend to use basic normal user defaults on their browsers, and have no awareness of caching issues with css/js etc, almost invariably fail to get the new css/js on change, which means the defaults for their browsers, mostly MSIE / Firefox, are not doing what they are told to do, they ignore changes and ignore last modified dates and do not validate, even with Expires: 0 set explicitly.

This was a good thread with a lot of good technical information, but it's also important to note how bad the support for this stuff is in particularly mobile devices. Every few months I have to add more layers of protection against their failure to follow the header commands they receive, or to properly interpet those commands.

List of swagger UI alternatives

Yes, there are a few of them.

Hosted solutions that support swagger:

Check the following articles for more details:

HTML how to clear input using javascript?

Try this :

<script type="text/javascript">
function clearThis(target){
    if(target.value == "[email protected]")
        target.value= "";

Possible to perform cross-database queries with PostgreSQL?

I have run into this before an came to the same conclusion about cross database queries as you. What I ended up doing was using schemas to divide the table space that way I could keep the tables grouped but still query them all.

Split string with multiple delimiters in Python

Luckily, Python has this built-in :)

import re
re.split('; |, ',str)

Following your comment:

>>> a='Beautiful, is; better*than\nugly'
>>> import re
>>> re.split('; |, |\*|\n',a)
['Beautiful', 'is', 'better', 'than', 'ugly']

VBA test if cell is in a range

@mywolfe02 gives a static range code so his inRange works fine but if you want to add dynamic range then use this one with inRange function of him.this works better with when you want to populate data to fix starting cell and last column is also fixed.

Sub DynamicRange()

Dim sht As Worksheet
Dim LastRow As Long
Dim StartCell As Range
Dim rng As Range

Set sht = Worksheets("xyz")
LastRow = sht.Cells.Find("*", SearchOrder:=xlByRows, SearchDirection:=xlPrevious).row
Set rng = Workbooks("Record.xlsm").Worksheets("xyz").Range(Cells(12, 2), Cells(LastRow, 12))

Debug.Print LastRow

If InRange(ActiveCell, rng) Then
'        MsgBox "Active Cell In Range!"
      MsgBox "Please select the cell within the range!"
  End If

End Sub 

Where to find Application Loader app in Mac?

You can also upload an app using the Application Loader tool by using it from the terminal:

MacBook-Pro:~ denis$ altool --upload-app -f "ios-app.ipa" -u "[email protected]" -p "yourpassword"

To use altool from anywhere in the terminal you could add it to your PATH env variable by typing in terminal:

MacBook-Pro:~ denis$ export PATH=$PATH:/Applications/\
MacBook-Pro:~ denis$ source ~/.bash_profile

Change Orientation of Bluestack : portrait/landscape mode

You could also change resolution of your bluestacks emulator. For example from 800x1280 to 1280x800

Here are instructions for how to change the screen resolution.

To change screen resolution in BlueStacks Android emulator you need to edit two registry items:

  1. Run regedit.exe

  2. Set new resolution (in decimal):




Kill all BlueStacks processes.

Restart BlueStacks

How to format numbers by prepending 0 to single-digit numbers?

with this function you can print with any n digits you want

function frmtDigit(num, n) {
    isMinus = num < 0;
    if (isMinus)
        num *= -1;
    digit = '';
    if (typeof n == 'undefined')
        n = 2;//two digits
    for (i = 1; i < n; i++) {
        if (num < (1 + Array(i + 1).join("0")))
            digit += '0';
    digit = (isMinus ? '-' : '') + digit + num;
    return digit;

Monitor the Graphics card usage

From Unix.SE: A simple command-line utility called gpustat now exists:

It is free software (MIT license) and is packaged in pypi. It is a wrapper of nvidia-smi.

How to output a comma delimited list in jinja python template?

And using the joiner from

{% set comma = joiner(",") %}
{% for user in userlist %}
    {{ comma() }}<a href="/profile/{{ user }}/">{{ user }}</a>
{% endfor %}  

It's made for this exact purpose. Normally a join or a check of forloop.last would suffice for a single list, but for multiple groups of things it's useful.

A more complex example on why you would use it.

{% set pipe = joiner("|") %}
{% if categories %} {{ pipe() }}
    Categories: {{ categories|join(", ") }}
{% endif %}
{% if author %} {{ pipe() }}
    Author: {{ author() }}
{% endif %}
{% if can_edit %} {{ pipe() }}
    <a href="?action=edit">Edit</a>
{% endif %}

How do I handle ImeOptions' done button click?

While most people have answered the question directly, I wanted to elaborate more on the concept behind it. First, I was drawn to the attention of IME when I created a default Login Activity. It generated some code for me which included the following:


You should already be familiar with the inputType attribute. This just informs Android the type of text expected such as an email address, password or phone number. The full list of possible values can be found here.

It was, however, the attribute imeOptions="actionUnspecified" that I didn't understand its purpose. Android allows you to interact with the keyboard that pops up from bottom of screen when text is selected using the InputMethodManager. On the bottom corner of the keyboard, there is a button, typically it says "Next" or "Done", depending on the current text field. Android allows you to customize this using android:imeOptions. You can specify a "Send" button or "Next" button. The full list can be found here.

With that, you can then listen for presses on the action button by defining a TextView.OnEditorActionListener for the EditText element. As in your example:

editText.setOnEditorActionListener(new EditText.OnEditorActionListener() {
    public boolean onEditorAction(EditText v, int actionId, KeyEvent event) {
    if (actionId == EditorInfo.IME_ACTION_DONE) {
       //do here your stuff f
       return true;
    return false;

Now in my example I had android:imeOptions="actionUnspecified" attribute. This is useful when you want to try to login a user when they press the enter key. In your Activity, you can detect this tag and then attempt the login:

    mPasswordView = (EditText) findViewById(;
    mPasswordView.setOnEditorActionListener(new TextView.OnEditorActionListener() {
        public boolean onEditorAction(TextView textView, int id, KeyEvent keyEvent) {
            if (id == || id == EditorInfo.IME_NULL) {
                return true;
            return false;

Create a nonclustered non-unique index within the CREATE TABLE statement with SQL Server

The accepted answer of how to create an Index inline a Table creation script did not work for me. This did:

CREATE TABLE [dbo].[TableToBeCreated]
    ,[ForeignKeyId] BIGINT NOT NULL
    ,CONSTRAINT [FK_TableToBeCreated_ForeignKeyId_OtherTable_Id] FOREIGN KEY ([ForeignKeyId]) REFERENCES [dbo].[OtherTable]([Id])
    ,INDEX [IX_TableToBeCreated_ForeignKeyId] NONCLUSTERED ([ForeignKeyId])

Remember, Foreign Keys do not create Indexes, so it is good practice to index them as you will more than likely be joining on them.

How to return multiple rows from the stored procedure? (Oracle PL/SQL)

I think you want to return a REFCURSOR:

create function test_cursor 
            return sys_refcursor
                    c_result sys_refcursor;
                    open c_result for
                    select * from dual;
                    return c_result;

Update: If you need to call this from SQL, use a table function like @Tony Andrews suggested.

How to insert array of data into mysql using php

    foreach($EMailArr as $key => $value){

    $R_ID = (int) $value['R_ID'];
    $email = mysql_real_escape_string( $value['email'] );
    $name = mysql_real_escape_string( $value['name'] );

    $sql = "INSERT INTO email_list (R_ID, EMAIL, NAME) values ('$R_ID', '$email', '$name')";
    mysql_query($sql) or exit(mysql_error()); 

A better example solution with PDO:

 $q = $sql->prepare("INSERT INTO `email_list` 
                     SET `R_ID` = ?, `EMAIL` = ?, `NAME` = ?");

 foreach($EMailArr as $value){
   $q ->execute( array( $value['R_ID'], $value['email'], $value['name'] ));

Set angular scope variable in markup

If you not in a loop, you can use ng-init else you can use


the "" alows not display your var

How to output in CLI during execution of PHP Unit tests?

You should really think about your intentions: If you need the information now when debugging to fix the test, you will need it next week again when the tests break.

This means that you will need the information always when the test fails - and adding a var_dump to find the cause is just too much work. Rather put the data into your assertions.

If your code is too complex for that, split it up until you reach a level where one assertion (with a custom message) tells you enough to know where it broke, why and how to fix the code.

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

The blog post Grab the Picture of a Facebook Graph Object might offer another form of solution. Use the code in the tutorial along with the Facebook's Graph API and its PHP SDK library.

... And try not to use file_get_contents (unless you're ready to face the consequences - see file_get_contents vs curl).

How to multiply duration by integer?

You have to cast it to a correct format Playground.

yourTime := rand.Int31n(1000)
time.Sleep(time.Duration(yourTime) * time.Millisecond)

If you will check documentation for sleep, you see that it requires func Sleep(d Duration) duration as a parameter. Your rand.Int31n returns int32.

The line from the example works (time.Sleep(100 * time.Millisecond)) because the compiler is smart enough to understand that here your constant 100 means a duration. But if you pass a variable, you should cast it.

How to print HTML content on click of a button, but not the page?

Below Code May Be Help You :

function printPage(id)
   var html="<html>";
   html+= document.getElementById(id).innerHTML;


   var printWin ='','','left=0,top=0,width=1,height=1,toolbar=0,scrollbars=0,status  =0');
<div id="block1">
<table border="1" >
<th colspan="3">Block 1</th>


<div id="block2">
    This is Block 2 content

<input type="button" value="Print Block 1" onclick="printPage('block1');"></input>
<input type="button" value="Print Block 2" onclick="printPage('block2');"></input>

Install a .NET windows service without InstallUtil.exe

Here is a class I use when writing services. I usually have an interactive screen that comes up when the service is not called. From there I use the class as needed. It allows for multiple named instances on the same machine -hence the InstanceID field

Sample Call

  IntegratedServiceInstaller Inst = new IntegratedServiceInstaller();
  Inst.Install("MySvc", "My Sample Service", "Service that executes something",
// System.ServiceProcess.ServiceAccount.LocalService,      // this is more secure, but only available in XP and above and WS-2003 and above
  System.ServiceProcess.ServiceAccount.LocalSystem,       // this is required for WS-2000
  if (controller == null)
    controller = new System.ServiceProcess.ServiceController(String.Format("MySvc_{0}", _InstanceID), ".");
                if (controller.Status == System.ServiceProcess.ServiceControllerStatus.Running)
                    Start_Stop.Text = "Stop Service";
                    Start_Stop_Debugging.Enabled = false;
                    Start_Stop.Text = "Start Service";
                    Start_Stop_Debugging.Enabled = true;

The class itself

using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;
using Microsoft.Win32;

namespace MySvc
    class IntegratedServiceInstaller
        public void Install(String ServiceName, String DisplayName, String Description,
            String InstanceID,
            System.ServiceProcess.ServiceAccount Account, 
            System.ServiceProcess.ServiceStartMode StartMode)
            System.ServiceProcess.ServiceProcessInstaller ProcessInstaller = new System.ServiceProcess.ServiceProcessInstaller();
            ProcessInstaller.Account = Account;

            System.ServiceProcess.ServiceInstaller SINST = new System.ServiceProcess.ServiceInstaller();

            System.Configuration.Install.InstallContext Context = new System.Configuration.Install.InstallContext();
            string processPath = Process.GetCurrentProcess().MainModule.FileName;
            if (processPath != null && processPath.Length > 0)
                System.IO.FileInfo fi = new System.IO.FileInfo(processPath);

                String path = String.Format("/assemblypath={0}", fi.FullName);
                String[] cmdline = { path };
                Context = new System.Configuration.Install.InstallContext("", cmdline);

            SINST.Context = Context;
            SINST.DisplayName = String.Format("{0} - {1}", DisplayName, InstanceID);
            SINST.Description = String.Format("{0} - {1}", Description, InstanceID);
            SINST.ServiceName = String.Format("{0}_{1}", ServiceName, InstanceID);
            SINST.StartType = StartMode;
            SINST.Parent = ProcessInstaller;

            SINST.ServicesDependedOn = new String[] { "Spooler", "Netlogon", "Netman" };

            System.Collections.Specialized.ListDictionary state = new System.Collections.Specialized.ListDictionary();

            using (RegistryKey oKey = Registry.LocalMachine.OpenSubKey(String.Format(@"SYSTEM\CurrentControlSet\Services\{0}_{1}", ServiceName, InstanceID), true))
                    Object sValue = oKey.GetValue("ImagePath");
                    oKey.SetValue("ImagePath", sValue);
                catch (Exception Ex)

        public void Uninstall(String ServiceName, String InstanceID)
            System.ServiceProcess.ServiceInstaller SINST = new System.ServiceProcess.ServiceInstaller();

            System.Configuration.Install.InstallContext Context = new System.Configuration.Install.InstallContext("c:\\install.log", null);
            SINST.Context = Context;
            SINST.ServiceName = String.Format("{0}_{1}", ServiceName, InstanceID);

How do I uninstall nodejs installed from pkg (Mac OS X)?

This is the full list of commands I used (Many thanks to the posters above):

sudo rm -rf /usr/local/lib/node /usr/local/lib/node_modules /var/db/receipts/org.nodejs.*
sudo rm -rf /usr/local/include/node /Users/$USER/.npm
sudo rm /usr/local/bin/node
sudo rm /usr/local/share/man/man1/node.1
brew install node

ORACLE and TRIGGERS (inserted, updated, deleted)

The NEW values (or NEW_BUFFER as you have renamed them) are only available when INSERTING and UPDATING. For DELETING you would need to use OLD (OLD_BUFFER). So your trigger would become:

  REFERENCING OLD AS old_buffer NEW AS new_buffer 
  FOR EACH ROW WHEN (new_buffer.field1 = 'HBP00' OR old_buffer.field1 = 'HBP00') 

You may need to add logic inside the trigger to cater for code that updates field1 from 'HBP000' to something else.

PyCharm error: 'No Module' when trying to import own module (python script)

I was getting the error with "Add source roots to PYTHONPATH" as well. My problem was that I had two folders with the same name, like project/subproject1/thing/src and project/subproject2/thing/src and I had both of them marked as source root. When I renamed one of the "thing" folders to "thing1" (any unique name), it worked.

Maybe if PyCharm automatically adds selected source roots, it doesn't use the full path and hence mixes up folders with the same name.

How can I convert a string to upper- or lower-case with XSLT?

In XSLT 1.0 the upper-case() and lower-case() functions are not available. If you're using a 1.0 stylesheet the common method of case conversion is translate():

<xsl:variable name="lowercase" select="'abcdefghijklmnopqrstuvwxyz'" />
<xsl:variable name="uppercase" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'" />

<xsl:template match="/">
  <xsl:value-of select="translate(doc, $lowercase, $uppercase)" />

How to get a value of an element by name instead of ID

let startDate = $('[name=daterangepicker_start]').val();

Using Excel VBA to run SQL query

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

References required for SQL

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

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

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

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

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

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

Ignore fields from Java object dynamically while sending as JSON from Spring MVC

If I were you and wanted to do so, I wouldn't use my User entity in Controller layer.Instead I create and use UserDto (Data transfer object) to communicate with business(Service) layer and Controller. You can use Apache BeanUtils(copyProperties method) to copy data from User entity to UserDto.

get all the elements of a particular form

var inputs = document.getElementById("formId").getElementsByTagName("input");
var inputs = document.forms[1].getElementsByTagName("input");

Update for 2020:

var inputs = document.querySelectorAll("#formId input");

how to set the default value to the drop down list control?

After your DataBind():

lstDepartment.SelectedIndex = 0;  //first item


lstDepartment.SelectedValue = "Yourvalue"

//add error checking, just an example, FindByValue may return null
lstDepartment.Items.FindByValue("Yourvalue").Selected = true;

//add error checking, just an example, FindByText may return null
lstDepartment.Items.FindByText("Yourvalue").Selected = true;

How to ALTER multiple columns at once in SQL Server

Thanks to Evan's code sample, I was able to modify it more and get it more specific to tables starting with, specific column names AND handle specifics for constraints too. I ran that code and then copied the [CODE] column and executed it without issue.

USE [Table_Name]
 AND (COLUMN_NAME = 'FormInserted' OR COLUMN_NAME = 'FormUpdated')
 AND DATA_TYPE = 'datetime'

Creating a Menu in Python

This should do it. You were missing a ) and you only need """ not 4 of them. Also you don't need a elif at the end.

while ans:
    1.Add a Student
    2.Delete a Student
    3.Look Up Student Record
    ans=raw_input("What would you like to do? ")
    if ans=="1":
      print("\nStudent Added")
    elif ans=="2":
      print("\n Student Deleted")
    elif ans=="3":
      print("\n Student Record Found")
    elif ans=="4":
      print("\n Goodbye") 
      ans = None
       print("\n Not Valid Choice Try again")

CharSequence VS String in Java?

I believe it is best to use CharSequence. The reason is that String implements CharSequence, therefore you can pass a String into a CharSequence, HOWEVER you cannot pass a CharSequence into a String, as CharSequence doesn't not implement String. ALSO, in Android the EditText.getText() method returns an Editable, which also implements CharSequence and can be passed easily into one, while not easily into a String. CharSequence handles all!

Append an int to a std::string

I have a feeling that your ClientID is not of a string type (zero-terminated char* or std::string) but some integral type (e.g. int) so you need to convert number to the string first:

std::stringstream ss;
ss << ClientID;

But you can use operator+ as well (instead of append):

query += ss.str();

SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column?

I was having the same question. Here is a working solution which is similar to eglasius's. I am using postgresql.

UPDATE QuestionTrackings
SET QuestionID = a.QuestionID
FROM QuestionTrackings q, QuestionAnswers a

It complains if q was used in place of table name in line 1, and nothing should precede QuestionID in line 2.

MySQL connection not working: 2002 No such file or directory

Restarting the mysql server might help. In my case, restarting the server saved a lot of time.

service mysql restart

P.S.- use sudo service mysql restart for non-root user.

Swift Beta performance: sorting arrays

Swift 4.1 introduces new -Osize optimization mode.

In Swift 4.1 the compiler now supports a new optimization mode which enables dedicated optimizations to reduce code size.

The Swift compiler comes with powerful optimizations. When compiling with -O the compiler tries to transform the code so that it executes with maximum performance. However, this improvement in runtime performance can sometimes come with a tradeoff of increased code size. With the new -Osize optimization mode the user has the choice to compile for minimal code size rather than for maximum speed.

To enable the size optimization mode on the command line, use -Osize instead of -O.

Further reading :

Change the background color in a twitter bootstrap modal?

I used couple of hours trying to figure how to remove background from launched modal, so far tried

.modal-backdrop {    background: none; }

Didn't work even I have tried to work with javascript like

 <script type="text/javascript">   
 $('#modal-id').on('',  function () {
       $("").hide();     })

Also didn't work either. I just added



<div class="modal fade" id="myModal" data-backdrop="false">......</div>

And Applying css CLASS

.modal {     background-color: transparent !important;  }

Now its working like a charm This worked with Bootstrap 3

Combine two integer arrays

NOTE: didn't test it

int[] concatArray(int[] a, int[] b) {
  int[] c = new int[a.length + b.length];
  int i = 0;
  for (int x : a) { c[i] = x; i ++; }
  for (int x : b) { c[i] = x; i ++; }
  return c;

Converting from hex to string

Like so?

static void Main()
    byte[] data = FromHex("47-61-74-65-77-61-79-53-65-72-76-65-72");
    string s = Encoding.ASCII.GetString(data); // GatewayServer
public static byte[] FromHex(string hex)
    hex = hex.Replace("-", "");
    byte[] raw = new byte[hex.Length / 2];
    for (int i = 0; i < raw.Length; i++)
        raw[i] = Convert.ToByte(hex.Substring(i * 2, 2), 16);
    return raw;

Define a struct inside a class in C++

Yes you can. In c++, class and struct are kind of similar. We can define not only structure inside a class, but also a class inside one. It is called inner class.

As an example I am adding a simple Trie class.

class Trie {
    struct node{
        node* alp[26];
        bool isend;
    node* root;
    node* createNode(){
        node* newnode=new node();
        for(int i=0; i<26; i++){
        return newnode;
    /** Initialize your data structure here. */
    Trie() {

    /** Inserts a word into the trie. */
    void insert(string word) {
        node* head=root;
        for(int i=0; i<word.length(); i++){
                node* newnode=createNode();

    /** Returns if the word is in the trie. */
    bool search(string word) {
        node* head=root;
        for(int i=0; i<word.length(); i++){
                return false;
        if(head->isend){return true;}
        return false;

    /** Returns if there is any word in the trie that starts with the given prefix. */
    bool startsWith(string prefix) {
        node* head=root;
        for(int i=0; i<prefix.length(); i++){
                return false;
        return true;

 * Your Trie object will be instantiated and called as such:
 * Trie* obj = new Trie();
 * obj->insert(word);
 * bool param_2 = obj->search(word);
 * bool param_3 = obj->startsWith(prefix);

Easiest way to compare arrays in C#

If you would like to handle null inputs gracefully, and ignore the order of items, try the following solution:

static class Extensions
    public static bool ItemsEqual<TSource>(this TSource[] array1, TSource[] array2)
        if (array1 == null && array2 == null)
            return true;
        if (array1 == null || array2 == null)
            return false;
        if (array1.Count() != array2.Count())
            return false;
        return !array1.Except(array2).Any() && !array2.Except(array1).Any();

The test code looks like:

public static void Main()
    int[] a1 = new int[] { 1, 2, 3 };
    int[] a2 = new int[] { 3, 2, 1 };
    int[] a3 = new int[] { 1, 3 };
    Console.WriteLine(a1.ItemsEqual(a2)); // Output: True.
    Console.WriteLine(a2.ItemsEqual(a3)); // Output: False.
    Console.WriteLine(a3.ItemsEqual(a2)); // Output: False.
    int[] a4 = new int[] { 1, 1 };
    int[] a5 = new int[] { 1, 2 };
    Console.WriteLine(a4.ItemsEqual(a5)); // Output: False 
    Console.WriteLine(a5.ItemsEqual(a4)); // Output: False 
    int[] a6 = null;
    int[] a7 = null;
    int[] a8 = new int[0];

    Console.WriteLine(a6.ItemsEqual(a7)); // Output: True. No Exception.
    Console.WriteLine(a8.ItemsEqual(a6)); // Output: False. No Exception.
    Console.WriteLine(a7.ItemsEqual(a8)); // Output: False. No Exception.

Is there a Newline constant defined in Java like Environment.Newline in C#?

Be aware that this property isn't as useful as many people think it is. Just because your app is running on a Windows machine, for example, doesn't mean the file it's reading will be using Windows-style line separators. Many web pages contain a mixture of "\n" and "\r\n", having been cobbled together from disparate sources. When you're reading text as a series of logical lines, you should always look for all three of the major line-separator styles: Windows ("\r\n"), Unix/Linux/OSX ("\n") and pre-OSX Mac ("\r").

When you're writing text, you should be more concerned with how the file will be used than what platform you're running on. For example, if you expect people to read the file in Windows Notepad, you should use "\r\n" because it only recognizes the one kind of separator.

How to check if an item is selected from an HTML drop down list?

var card = document.getElementById("cardtype");
if(card.selectedIndex == 0) {
     alert('select one answer');
else {
    var selectedText = card.options[card.selectedIndex].text;

How to import set of icons into Android Studio project

For custom images you created yourself, you can do without the plugin:

Right click on res folder, selecting New > Image Asset. browse image file. Select the largest image you have.

It will create all densities for you. Make sure you select an original image, not an asset studio image with an alpha, or you will semi-transpartent it twice.

JSON: why are forward slashes escaped?

I asked the same question some time ago and had to answer it myself. Here's what I came up with:

It seems, my first thought [that it comes from its JavaScript roots] was correct.

'\/' === '/' in JavaScript, and JSON is valid JavaScript. However, why are the other ignored escapes (like \z) not allowed in JSON?

The key for this was reading, followed by The feature of the slash escape allows JSON to be embedded in HTML (as SGML) and XML.

Serialize JavaScript object into JSON string

Below is another way by which we can JSON data with JSON.stringify() function

var Utils = {};
Utils.MyClass1 = function (id, member) { = id;
    this.member = member;
var myobject = { MyClass1: new Utils.MyClass1("5678999", "text") };

Difference between .keystore file and .jks file

You are confused on this.

A keystore is a container of certificates, private keys etc.

There are specifications of what should be the format of this keystore and the predominant is the #PKCS12

JKS is Java's keystore implementation. There is also BKS etc.

These are all keystore types.

So to answer your question:

difference between .keystore files and .jks files

There is none. JKS are keystore files. There is difference though between keystore types. E.g. JKS vs #PKCS12

How and where to use ::ng-deep?

Just an update:

You should use ::ng-deep instead of /deep/ which seems to be deprecated.

Per documentation:

The shadow-piercing descendant combinator is deprecated and support is being removed from major browsers and tools. As such we plan to drop support in Angular (for all 3 of /deep/, >>> and ::ng-deep). Until then ::ng-deep should be preferred for a broader compatibility with the tools.

You can find it here

System.Windows.Markup.XamlParseException' occurred in PresentationFramework.dll?

When I had this problem, I had literally just forgot to fill in a parameter value in the XAML of the code.

For some reason though, the exception would send me to the CS of the WPF program rather than the XAML. No idea why.

Assign result of dynamic sql to variable

You should try this while getting SEQUENCE value in a variable from the dynamic table.

DECLARE @temp table (#temp varchar (MAX));
DECLARE @SeqID nvarchar(150);
DECLARE @Name varchar(150); 

SET @Name = (Select Name from table)
SET @SeqID = 'SELECT NEXT VALUE FOR '+ @Name + '_Sequence'
insert @temp exec (@SeqID)

SET @SeqID = (select * from @temp )


(1 row(s) affected)

Spring RestTemplate GET with parameters

OK, so I'm being an idiot and I'm confusing query parameters with url parameters. I was kinda hoping there would be a nicer way to populate my query parameters rather than an ugly concatenated String but there we are. It's simply a case of build the URL with the correct parameters. If you pass it as a String Spring will also take care of the encoding for you.

Eclipse : Maven search dependencies doesn't work

You can get this result if you are inside a corporate proxy and the new project isn't pointing to the correct settings.xml file with the proxy credentials.

You can also get this if you are using Maven proxy (Nexus, for example) and the index into the proxy is messed up somehow. I don't know a way to describe how to fix this. Fool around with it or call the one who set up the Maven proxy.

You can also get this if the new workspace hasn't yet downloaded the index either from Maven central or from the proxy. (This is the best one as you just have to wait a while and it will work itself out.)

How to Display Selected Item in Bootstrap Button Dropdown Title

Another simple way (Bootstrap 4) to work with multiple dropdowns

    $('.dropdown-item').on('click',  function(){
        var btnObj = $(this).parent().siblings('button');

I can pass a variable from a JSP scriptlet to JSTL but not from JSTL to a JSP scriptlet without an error

Scripts are raw java embedded in the page code, and if you declare variables in your scripts, then they become local variables embedded in the page.

In contrast, JSTL works entirely with scoped attributes, either at page, request or session scope. You need to rework your scriptlet to fish test out as an attribute:

<c:set var="test" value="test1"/>
  String resp = "abc";
  String test = pageContext.getAttribute("test");
  resp = resp + test;
  pageContext.setAttribute("resp", resp);
<c:out value="${resp}"/>

If you look at the docs for <c:set>, you'll see you can specify scope as page, request or session, and it defaults to page.

Better yet, don't use scriptlets at all: they make the baby jesus cry.

Date validation with ASP.NET validator

Best option would be

Add a compare validator to the web form. Set its controlToValidate. Set its Type property to Date. Set its operator property to DataTypeCheck eg:

    id="dateValidator" runat="server" 
    ErrorMessage="Please enter a valid date.">

Split Strings into words with multiple word boundary delimiters

join = lambda x: sum(x,[])  # a.k.a. flatten1([[1],[2,3],[4]]) -> [1,2,3,4]
# ...alternatively...
join = lambda lists: [x for l in lists for x in l]

Then this becomes a three-liner:

fragments = [text]
for token in tokens:
    fragments = join(f.split(token) for f in fragments)


This is what in Haskell is known as the List monad. The idea behind the monad is that once "in the monad" you "stay in the monad" until something takes you out. For example in Haskell, say you map the python range(n) -> [1,2,...,n] function over a List. If the result is a List, it will be append to the List in-place, so you'd get something like map(range, [3,4,1]) -> [0,1,2,0,1,2,3,0]. This is known as map-append (or mappend, or maybe something like that). The idea here is that you've got this operation you're applying (splitting on a token), and whenever you do that, you join the result into the list.

You can abstract this into a function and have tokens=string.punctuation by default.

Advantages of this approach:

  • This approach (unlike naive regex-based approaches) can work with arbitrary-length tokens (which regex can also do with more advanced syntax).
  • You are not restricted to mere tokens; you could have arbitrary logic in place of each token, for example one of the "tokens" could be a function which splits according to how nested parentheses are.

Where do I find the line number in the Xcode editor?

If you don't want line numbers shown all the time another way to find the line number of a piece of code is to just click in the left-most margin and create a breakpoint (a small blue arrow appears) then go to the breakpoint navigator (?7) where it will list the breakpoint with its line number. You can delete the breakpoint by right clicking on it.

What is the difference between a function expression vs declaration in JavaScript?

The first statement depends on the context in which it is declared.

If it is declared in the global context it will create an implied global variable called "foo" which will be a variable which points to the function. Thus the function call "foo()" can be made anywhere in your javascript program.

If the function is created in a closure it will create an implied local variable called "foo" which you can then use to invoke the function inside the closure with "foo()"


I should have also said that function statements (The first one) are parsed before function expressions (The other 2). This means that if you declare the function at the bottom of your script you will still be able to use it at the top. Function expressions only get evaluated as they are hit by the executing code.


Statements 2 & 3 are pretty much equivalent to each other. Again if used in the global context they will create global variables and if used within a closure will create local variables. However it is worth noting that statement 3 will ignore the function name, so esentially you could call the function anything. Therefore

var foo = function foo() { return 5; }

Is the same as

var foo = function fooYou() { return 5; }

iOS - Calling App Delegate method from ViewController

Sounds like you just need a UINavigationController setup?

You can get the AppDelegate anywhere in the program via

YourAppDelegateName* blah = (YourAppDelegateName*)[[UIApplication sharedApplication]delegate];

In your app delegate you should have your navigation controller setup, either via IB or in code.

In code, assuming you've created your 'House overview' viewcontroller already it would be something like this in your AppDelegate didFinishLaunchingWithOptions...

self.m_window = [[[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds] autorelease];
self.m_navigationController = [[[UINavigationController alloc]initWithRootViewController:homeViewController]autorelease];
[m_window addSubview:self.m_navigationController.view];

After this you just need a viewcontroller per 'room' and invoke the following when a button click event is picked up...

YourAppDelegateName* blah = (YourAppDelegateName*)[[UIApplication sharedApplication]delegate];
[blah.m_navigationController pushViewController:newRoomViewController animated:YES];

I've not tested the above code so forgive any syntax errors but hope the pseudo code is of help...

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

You should be able to "MINUS" or "EXCEPT" depending on the flavor of SQL used by your DBMS.

select * from tableA
select * from tableB

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

Python 101: Can't open file: No such file or directory

Try uninstalling Python and then install it again, but this time make sure that the option Add Python to Path is marked as checked during the installation process.

How do you get the currently selected <option> in a <select> via JavaScript?

This will do it for you:

var yourSelect = document.getElementById( "your-select-id" );
alert( yourSelect.options[ yourSelect.selectedIndex ].value )

Rounding Bigdecimal values with 2 Decimal Places

You may try this:

public static void main(String[] args) {
    BigDecimal a = new BigDecimal("10.12345");
    System.out.println(toPrecision(a, 2));

private static BigDecimal toPrecision(BigDecimal dec, int precision) {
    String plain = dec.movePointRight(precision).toPlainString();
    return new BigDecimal(plain.substring(0, plain.indexOf("."))).movePointLeft(precision);



Can I scroll a ScrollView programmatically in Android?

Adding another answer that does not involve coordinates.

This will bring your desired view to focus (but not to the top position) :


public void RequestChildFocus (View child, View focused)

child - The child of this ViewParent that wants focus. This view will contain the focused view. It is not necessarily the view that actually has focus.

focused - The view that is a descendant of child that actually has focus

Function to Calculate Median in SQL Server

I try with several alternatives, but due my data records has repeated values, the ROW_NUMBER versions seems are not a choice for me. So here the query I used (a version with NTILE):

SELECT distinct
       MAX(CASE WHEN Percent50_Asc=1 THEN TotalDue END) OVER (PARTITION BY CustomerId)  +
       MIN(CASE WHEN Percent50_desc=1 THEN TotalDue END) OVER (PARTITION BY CustomerId) 
   )/2 MEDIAN
     NTILE(2) OVER (
         PARTITION BY CustomerId
         ORDER BY TotalDue ASC) AS Percent50_Asc,
     NTILE(2) OVER (
         PARTITION BY CustomerId
         ORDER BY TotalDue DESC) AS Percent50_desc
   FROM Sales.SalesOrderHeader SOH
) x
ORDER BY CustomerId;

MySQL, Concatenate two columns

In query, CONCAT_WS() function.

This function not only add multiple string values and makes them a single string value. It also let you define separator ( ” “, ” , “, ” – “,” _ “, etc.).

Syntax –

CONCAT_WS( SEPERATOR, column1, column2, ... )


CONCAT_WS( " ", subject, year ) AS subject_year 
FROM table

How can I find the version of the Fedora I use?

You could try

lsb_release -a

which works on at least Debian and Ubuntu (and since it's LSB, it should surely be on most of the other mainstream distros at least). suggests it's been around quite a while.

How do I properly 'printf' an integer and a string in C?

Try this code my friend...

int main(){
   char *s1, *s2;
   char str[10];

   printf("type a string: ");
   scanf("%s", str);

   s1 = &str[0];
   s2 = &str[2];

   printf("%c\n", *s1);   //use %c instead of %s and *s1 which is the content of position 1
   printf("%c\n", *s2);   //use %c instead of %s and *s3 which is the content of position 1

   return 0;

How to read a .xlsx file using the pandas Library in iPython?

If you use read_excel() on a file opened using the function open(), make sure to add rb to the open function to avoid encoding errors

How is AngularJS different from jQuery

I think this is a very good chart describing the differences in short. A quick glance at it shows most of the differences.

enter image description here

One thing I would like to add is that, AngularJS can be made to follow the MVVM design pattern while jQuery does not follow any of the standard Object Oriented patterns.

Setting the focus to a text field

In a JFrame or JDialog you can always overwrite the setVisible() method, it works well. I haven't tried in a JPanel, but can be an alternative.

public void setVisible(boolean value) {

CMD what does /im (taskkill)?

If you type the executable name and a /? switch at the command line, there is typically help information available. Doing so with taskkill /? provides the following, for instance:

TASKKILL [/S system [/U username [/P [password]]]]
         { [/FI filter] [/PID processid | /IM imagename] } [/T] [/F]

    This tool is used to terminate tasks by process id (PID) or image name.

Parameter List:
    /S    system           Specifies the remote system to connect to.

    /U    [domain\]user    Specifies the user context under which the
                           command should execute.

    /P    [password]       Specifies the password for the given user
                           context. Prompts for input if omitted.

    /FI   filter           Applies a filter to select a set of tasks.
                           Allows "*" to be used. ex. imagename eq acme*

    /PID  processid        Specifies the PID of the process to be terminated.
                           Use TaskList to get the PID.

    /IM   imagename        Specifies the image name of the process
                           to be terminated. Wildcard '*' can be used
                           to specify all tasks or image names.

    /T                     Terminates the specified process and any
                           child processes which were started by it.

    /F                     Specifies to forcefully terminate the process(es).

    /?                     Displays this help message.

    Filter Name   Valid Operators           Valid Value(s)
    -----------   ---------------           -------------------------
    STATUS        eq, ne                    RUNNING |
                                            NOT RESPONDING | UNKNOWN
    IMAGENAME     eq, ne                    Image name
    PID           eq, ne, gt, lt, ge, le    PID value
    SESSION       eq, ne, gt, lt, ge, le    Session number.
    CPUTIME       eq, ne, gt, lt, ge, le    CPU time in the format
                                            of hh:mm:ss.
                                            hh - hours,
                                            mm - minutes, ss - seconds
    MEMUSAGE      eq, ne, gt, lt, ge, le    Memory usage in KB
    USERNAME      eq, ne                    User name in [domain\]user
    MODULES       eq, ne                    DLL name
    SERVICES      eq, ne                    Service name
    WINDOWTITLE   eq, ne                    Window title

    1) Wildcard '*' for /IM switch is accepted only when a filter is applied.
    2) Termination of remote processes will always be done forcefully (/F).
    3) "WINDOWTITLE" and "STATUS" filters are not considered when a remote
       machine is specified.

    TASKKILL /IM notepad.exe
    TASKKILL /PID 1230 /PID 1241 /PID 1253 /T
    TASKKILL /F /IM cmd.exe /T 
    TASKKILL /F /FI "PID ge 1000" /FI "WINDOWTITLE ne untitle*"
    TASKKILL /S system /U domain\username /FI "USERNAME ne NT*" /IM *
    TASKKILL /S system /U username /P password /FI "IMAGENAME eq note*"

You can also find this information, as well as documentation for most of the other command-line utilities, in the Microsoft TechNet Command-Line Reference

Docker and securing passwords

run-time only solution

docker-compose also provides a non-swarm mode solution (since v1.11: Secrets using bind mounts).

The secrets are mounted as files below /run/secrets/ by docker-compose. This solves the problem at run-time (running the container), but not at build-time (building the image), because /run/secrets/ is not mounted at build-time. Furthermore this behavior depends on running the container with docker-compose.



FROM alpine
RUN cat /run/secrets/password
CMD sleep inifinity


version: '3.1'
    build: .
      - password

    file: password.txt

To build, execute:

docker-compose up -d

Further reading:

How do I tell Python to convert integers into words

And here comes my solution :) It is various of earlier solutions, but developed on my own - maybe somebody enjoy it more then other propositions.

TENS = {30: 'thirty', 40: 'forty', 50: 'fifty', 60: 'sixty', 70: 'seventy', 80: 'eighty', 90: 'ninety'}
    'zero', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'ten',
    'eleven', 'twelve', 'thirteen', 'fourteen', 'fifteen', 'sixteen', 'seventeen', 'eighteen', 'nineteen', 'twenty'

def number_to_english(n):
    if any(not x.isdigit() for x in str(n)):
        return ''

    if n <= 20:
        return ZERO_TO_TWENTY[n]
    elif n < 100 and n % 10 == 0:
        return TENS[n]
    elif n < 100:
        return number_to_english(n - (n % 10)) + ' ' + number_to_english(n % 10)
    elif n < 1000 and n % 100 == 0:
        return number_to_english(n / 100) + ' hundred'
    elif n < 1000:
        return number_to_english(n / 100) + ' hundred ' + number_to_english(n % 100)
    elif n < 1000000:
        return number_to_english(n / 1000) + ' thousand ' + number_to_english(n % 1000)

    return ''

It is recoursive solution and can be easily expand for bigger numbers

HTML select dropdown list

Simple, I suppose. The onclick attribute works nicely...

<select onchange="if(this.value == '') this.selectedIndex = 1; ">_x000D_
  <option value="">Select an Option</option>_x000D_
  <option value="one">Option 1</option>_x000D_
  <option value="two">Option 2</option>_x000D_

After a different option is selected, if the first option is selected, Option 1 will be selected. If you want an explanation on the javascript, just ask.

How to include a sub-view in Blade templates?

As of Laravel 5.6, if you have this kind of structure and you want to include another blade file inside a subfolder,

|--- views

|------- parentFolder (Folder)

|---------- name.blade.php (Blade File)

|---------- childFolder (Folder)

|-------------- mypage.blade.php (Blade File)



ImportError: No module named PyQt4.QtCore

Try this command to solve your problem.

sudo apt install build-essential python3-dev libqt4-dev

This works for me in python3.

Insert content into iFrame

If you want all the CSS thats on your webpage in your IFrame, try this:

var headClone, iFrameHead;

// Create a clone of the web-page head
headClone = $('head').clone();

// Find the head of the the iFrame we are looking for
iFrameHead = $('#iframe').contents().find('head');

// Replace 'iFrameHead with your Web page 'head'

// You should now have all the Web page CSS in the Iframe

Good Luck.

Are arrays passed by value or passed by reference in Java?

Everything in Java is passed by value. In case of an array (which is nothing but an Object), the array reference is passed by value (just like an object reference is passed by value).

When you pass an array to other method, actually the reference to that array is copied.

  • Any changes in the content of array through that reference will affect the original array.
  • But changing the reference to point to a new array will not change the existing reference in original method.

See this post: Is Java "pass-by-reference" or "pass-by-value"?

See this working example:

public static void changeContent(int[] arr) {

   // If we change the content of arr.
   arr[0] = 10;  // Will change the content of array in main()

public static void changeRef(int[] arr) {
   // If we change the reference
   arr = new int[2];  // Will not change the array in main()
   arr[0] = 15;

public static void main(String[] args) {
    int [] arr = new int[2];
    arr[0] = 4;
    arr[1] = 5;


    System.out.println(arr[0]);  // Will print 10.. 

    System.out.println(arr[0]);  // Will still print 10.. 
                                 // Change the reference doesn't reflect change here..

SQL Server 2008 R2 Express permissions -- cannot create database or modify users

I followed the steps in killthrush's answer and to my surprise it did not work. Logging in as sa I could see my Windows domain user and had made them a sysadmin, but when I tried logging in with Windows auth I couldn't see my login under logins, couldn't create databases, etc. Then it hit me. That login was probably tied to another domain account with the same name (with some sort of internal/hidden ID that wasn't right). I had left this organization a while back and then came back months later. Instead of re-activating my old account (which they might have deleted) they created a new account with the same domain\username and a new internal ID. Using sa I deleted my old login, re-added it with the same name and added sysadmin. I logged back in with Windows Auth and everything looks as it should. I can now see my logins (and others) and can do whatever I need to do as a sysadmin using my Windows auth login.

How to write and read a file with a HashMap?

HashMap implements Serializable so you can use normal serialization to write hashmap to file

Here is the link for Java - Serialization example

Pandas - Compute z-score for all columns

Using Scipy's zscore function:

df = pd.DataFrame(np.random.randint(100, 200, size=(5, 3)), columns=['A', 'B', 'C'])

|    |   A |   B |   C |
|  0 | 163 | 163 | 159 |
|  1 | 120 | 153 | 181 |
|  2 | 130 | 199 | 108 |
|  3 | 108 | 188 | 157 |
|  4 | 109 | 171 | 119 |

from scipy.stats import zscore

|    |         A |         B |         C |
|  0 |  1.83447  | -0.708023 |  0.523362 |
|  1 | -0.297482 | -1.30804  |  1.3342   |
|  2 |  0.198321 |  1.45205  | -1.35632  |
|  3 | -0.892446 |  0.792025 |  0.449649 |
|  4 | -0.842866 | -0.228007 | -0.950897 |

If not all the columns of your data frame are numeric, then you can apply the Z-score function only to the numeric columns using the select_dtypes function:

# Note that `select_dtypes` returns a data frame. We are selecting only the columns
numeric_cols = df.select_dtypes(include=[np.number]).columns

|    |         A |         B |         C |
|  0 |  1.83447  | -0.708023 |  0.523362 |
|  1 | -0.297482 | -1.30804  |  1.3342   |
|  2 |  0.198321 |  1.45205  | -1.35632  |
|  3 | -0.892446 |  0.792025 |  0.449649 |
|  4 | -0.842866 | -0.228007 | -0.950897 |

Vim: How to insert in visual block mode?

Try this

After selecting a block of text, press Shift+i or capital I.

Lowercase i will not work.

Then type the things you want and finally to apply it to all lines, press Esc twice.

If this doesn't work...

Check if you have +visualextra enabled in your version of Vim.

You can do this by typing in :ver and scrolling through the list of features. (You might want to copy and paste it into a buffer and do incremental search because the format is odd.)

Enabling it is outside the scope of this question but I'm sure you can find it somewhere.

Check if an element contains a class in JavaScript?

I think that perfect solution will be this

if ($(this).hasClass("your_Class")) 

Check if list<t> contains any of another list

Here is a sample to find if there are match elements in another list

List<int> nums1 = new List<int> { 2, 4, 6, 8, 10 };
List<int> nums2 = new List<int> { 1, 3, 6, 9, 12};

if (nums1.Any(x => nums2.Any(y => y == x)))
    Console.WriteLine("There are equal elements");
    Console.WriteLine("No Match Found!");

Loop over array dimension in plpgsql

Since PostgreSQL 9.1 there is the convenient FOREACH:

   m   varchar[];
   arr varchar[] := array[['key1','val1'],['key2','val2']];
      RAISE NOTICE 'another_func(%,%)',m[1], m[2];

Solution for older versions:

   arr varchar[] := '{{key1,val1},{key2,val2}}';
   FOR i IN array_lower(arr, 1) .. array_upper(arr, 1)
      RAISE NOTICE 'another_func(%,%)',arr[i][1], arr[i][2];

Also, there is no difference between varchar[] and varchar[][] for the PostgreSQL type system. I explain in more detail here.

The DO statement requires at least PostgreSQL 9.0, and LANGUAGE plpgsql is the default (so you can omit the declaration).

How to execute logic on Optional if not present?

For those of you who want to execute a side-effect only if an optional is absent

i.e. an equivalent of ifAbsent() or ifNotPresent() here is a slight modification to the great answers already provided.

myOptional.ifPresentOrElse(x -> {}, () -> {
  // logic goes here

Select option padding not working in chrome

This simple hack will indent the text. Works well.

select {
  text-indent: 5px;

Encrypt and Decrypt text with RSA in PHP

Yes. Look at

It gives sample code examples for RSA encryption and decryption in PHP as well as RSA encryption in javascript.

If you want to encrypt text instead of just base 10 numbers, you'll also need a base to base conversion. That is convert text to a very large number. Text is really just writing in base 63. 26 lowercase letters plus 26 uppercase + 10 numerals + space character. The code for that is below also.

The $GETn parameter is a file name that holds keys for the cryption functions. If you don't figure it out, ask. I'll help.

I actually posted this whole encryption library yesterday, but Brad Larson a mod, killed it and said this kind of stuff isn't really what Stack Overflow is about. But you can still find all the code examples and the whole function library to carry out client/server encryption decryption for AJAX at the link above.

function RSAencrypt( $num, $GETn){
    if ( file_exists( 'temp/bigprimes'.hash( 'sha256', $GETn).'.php')){
        $t= explode( '>,', file_get_contents('temp/bigprimes'.hash( 'sha256', $GETn).'.php'));
        return JL_powmod( $num, $t[4], $t[10]); 
        return false;

function RSAdecrypt( $num, $GETn){
    if ( file_exists( 'temp/bigprimes'.hash( 'sha256', $GETn).'.php')){
        $t= explode( '>,', file_get_contents('temp/bigprimes'.hash( 'sha256', $GETn).'.php'));
        return JL_powmod( $num, $t[8], $t[10]);     
        return false;

function JL_powmod( $num, $pow, $mod) {
    if ( function_exists('bcpowmod')) {
        return bcpowmod( $num, $pow, $mod);
    $result= '1';
    do {
        if ( !bccomp( bcmod( $pow, '2'), '1')) {
            $result = bcmod( bcmul( $result, $num), $mod);
       $num = bcmod( bcpow( $num, '2'), $mod);

       $pow = bcdiv( $pow, '2');
    } while ( bccomp( $pow, '0'));
    return $result;

function baseToBase ($message, $fromBase, $toBase){
    $from= strlen( $fromBase);
    $b[$from]= $fromBase; 
    $to= strlen( $toBase);
    $b[$to]= $toBase; 

    $result= substr( $b[$to], 0, 1);

    $f= substr( $b[$to], 1, 1);

    $tf= digit( $from, $b[$to]);

    for ($i=strlen($message)-1; $i>=0; $i--){
        $result= badd( $result, bmul( digit( strpos( $b[$from], substr( $message, $i, 1)), $b[$to]), $f, $b[$to]), $b[$to]);
        $f= bmul($f, $tf, $b[$to]);
    return $result;

function digit( $from, $bto){   
    $to= strlen( $bto);
    $b[$to]= $bto; 

    $t[0]= intval( $from);
    $i= 0;
    while ( $t[$i] >= intval( $to)){
        if ( !isset( $t[$i+1])){ 
            $t[$i+1]= 0;
        while ( $t[$i] >= intval( $to)){
            $t[$i]= $t[$i] - intval( $to);

    $res= '';
    for ( $i=count( $t)-1; $i>=0; $i--){ 
        $res.= substr( $b[$to], $t[$i], 1);
    return $res;

function badd( $n1, $n2, $nbase){
    $base= strlen( $nbase);
    $b[$base]= $nbase; 

    while ( strlen( $n1) < strlen( $n2)){
        $n1= substr( $b[$base], 0, 1) . $n1;
    while ( strlen( $n1) > strlen( $n2)){
        $n2= substr( $b[$base], 0, 1) . $n2;
    $n1= substr( $b[$base], 0, 1) . $n1;    
    $n2= substr( $b[$base], 0, 1) . $n2;
    $m1= array();
    for ( $i=0; $i<strlen( $n1); $i++){
        $m1[$i]= strpos( $b[$base], substr( $n1, (strlen( $n1)-$i-1), 1));
    $res= array();
    $m2= array();
    for ($i=0; $i<strlen( $n1); $i++){
        $m2[$i]= strpos( $b[$base], substr( $n2, (strlen( $n1)-$i-1), 1));
        $res[$i]= 0;
    for ($i=0; $i<strlen( $n1)  ; $i++){
        $res[$i]= $m1[$i] + $m2[$i] + $res[$i];
        if ($res[$i] >= $base){
            $res[$i]= $res[$i] - $base;
    $o= '';
    for ($i=0; $i<strlen( $n1); $i++){
        $o= substr( $b[$base], $res[$i], 1).$o;
    $t= false;
    $o= '';
    for ($i=strlen( $n1)-1; $i>=0; $i--){
        if ($res[$i] > 0 || $t){    
            $o.= substr( $b[$base], $res[$i], 1);
            $t= true;
    return $o;
function bmul( $n1, $n2, $nbase){
    $base= strlen( $nbase);
    $b[$base]= $nbase; 

    $m1= array();
    for ($i=0; $i<strlen( $n1); $i++){
        $m1[$i]= strpos( $b[$base], substr($n1, (strlen( $n1)-$i-1), 1));
    $m2= array();
    for ($i=0; $i<strlen( $n2); $i++){
        $m2[$i]= strpos( $b[$base], substr($n2, (strlen( $n2)-$i-1), 1));
    $res= array();
    for ($i=0; $i<strlen( $n1)+strlen( $n2)+2; $i++){
        $res[$i]= 0;
    for ($i=0; $i<strlen( $n1)  ; $i++){
        for ($j=0; $j<strlen( $n2)  ; $j++){
            $res[$i+$j]= ($m1[$i] * $m2[$j]) + $res[$i+$j];
            while ( $res[$i+$j] >= $base){
                $res[$i+$j]= $res[$i+$j] - $base;
    $t= false;
    $o= '';
    for ($i=count( $res)-1; $i>=0; $i--){
        if ($res[$i]>0 || $t){  
            $o.= substr( $b[$base], $res[$i], 1);
            $t= true;
    return $o;

Checking for an empty file in C++

pFile = fopen("file", "r");
fseek (pFile, 0, SEEK_END);
size=ftell (pFile);
if (size) {
  fseek(pFile, 0, SEEK_SET);
  do something...


What is the proper declaration of main in C++?

The main function must be declared as a non-member function in the global namespace. This means that it cannot be a static or non-static member function of a class, nor can it be placed in a namespace (even the unnamed namespace).

The name main is not reserved in C++ except as a function in the global namespace. You are free to declare other entities named main, including among other things, classes, variables, enumerations, member functions, and non-member functions not in the global namespace.

You can declare a function named main as a member function or in a namespace, but such a function would not be the main function that designates where the program starts.

The main function cannot be declared as static or inline. It also cannot be overloaded; there can be only one function named main in the global namespace.

The main function cannot be used in your program: you are not allowed to call the main function from anywhere in your code, nor are you allowed to take its address.

The return type of main must be int. No other return type is allowed (this rule is in bold because it is very common to see incorrect programs that declare main with a return type of void; this is probably the most frequently violated rule concerning the main function).

There are two declarations of main that must be allowed:

int main()               // (1)
int main(int, char*[])   // (2)

In (1), there are no parameters.

In (2), there are two parameters and they are conventionally named argc and argv, respectively. argv is a pointer to an array of C strings representing the arguments to the program. argc is the number of arguments in the argv array.

Usually, argv[0] contains the name of the program, but this is not always the case. argv[argc] is guaranteed to be a null pointer.

Note that since an array type argument (like char*[]) is really just a pointer type argument in disguise, the following two are both valid ways to write (2) and they both mean exactly the same thing:

int main(int argc, char* argv[])
int main(int argc, char** argv)

Some implementations may allow other types and numbers of parameters; you'd have to check the documentation of your implementation to see what it supports.

main() is expected to return zero to indicate success and non-zero to indicate failure. You are not required to explicitly write a return statement in main(): if you let main() return without an explicit return statement, it's the same as if you had written return 0;. The following two main() functions have the same behavior:

int main() { }
int main() { return 0; }

There are two macros, EXIT_SUCCESS and EXIT_FAILURE, defined in <cstdlib> that can also be returned from main() to indicate success and failure, respectively.

The value returned by main() is passed to the exit() function, which terminates the program.

Note that all of this applies only when compiling for a hosted environment (informally, an environment where you have a full standard library and there's an OS running your program). It is also possible to compile a C++ program for a freestanding environment (for example, some types of embedded systems), in which case startup and termination are wholly implementation-defined and a main() function may not even be required. If you're writing C++ for a modern desktop OS, though, you're compiling for a hosted environment.

How to change the button text of <input type="file" />?

You can put an image instead, and do it like this:


<img src="/images/uploadButton.png" id="upfile1" style="cursor:pointer" />
<input type="file" id="file1"  name="file1" style="display:none" />


$("#upfile1").click(function () {

CAVEAT: In IE9 and IE10 if you trigger the onClick in a file input via javascript, the form will be flagged as 'dangerous' and cannot be submitted with javascript, not sure if it can be submitted traditionally.

Difference between links and depends_on in docker_compose.yml

[Update Sep 2016]: This answer was intended for docker compose file v1 (as shown by the sample compose file below). For v2, see the other answer by @Windsooon.

[Original answer]:

It is pretty clear in the documentation. depends_on decides the dependency and the order of container creation and links not only does these, but also

Containers for the linked service will be reachable at a hostname identical to the alias, or the service name if no alias was specified.

For example, assuming the following docker-compose.yml file:

  image: example/my_web_app:latest
    - db
    - cache

  image: postgres:latest

  image: redis:latest

With links, code inside web will be able to access the database using db:5432, assuming port 5432 is exposed in the db image. If depends_on were used, this wouldn't be possible, but the startup order of the containers would be correct.

Dump a NumPy array into a csv file

I believe you can also accomplish this quite simply as follows:

  1. Convert Numpy array into a Pandas dataframe
  2. Save as CSV

e.g. #1:

    # Libraries to import
    import pandas as pd
    import nump as np

    #N x N numpy array (dimensions dont matter)
    corr_mat    #your numpy array
    my_df = pd.DataFrame(corr_mat)  #converting it to a pandas dataframe

e.g. #2:

    #save as csv 
    my_df.to_csv('foo.csv', index=False)   # "foo" is the name you want to give
                                           # to csv file. Make sure to add ".csv"
                                           # after whatever name like in the code

How to fix Error: "Could not find schema information for the attribute/element" by creating schema

Quickest, easiest laziest way to solve the problem:

  1. Right-click on the project icon in Solution Explorer and choose "Properties".
  2. Go to the "Application" tab and choose an earlier .NET target framework.
  3. Save changes.
  4. Go to the "Application" tab and choose the initial .NET target framework.
  5. Save changes => problem solved!

When is null or undefined used in JavaScript?

Regarding this topic the specification (ecma-262) is quite clear

I found it really useful and straightforward, so that I share it: - Here you will find Equality algorithm - Here you will find Strict equality algorithm

I bumped into it reading "Abstract equality, strict equality, and same value" from mozilla developer site, section sameness.

I hope you find it useful.

How to access ssis package variables inside script component

First List the Variable that you want to use them in Script task at ReadOnlyVariables in the Script task editor and Edit the Script

To use your ReadOnlyVariables in script code

String codeVariable = Dts.Variables["User::VariableNameinSSIS"].Value.ToString();

this line of code will treat the ssis package variable as a string.

DataFrame constructor not properly called! error

You are providing a string representation of a dict to the DataFrame constructor, and not a dict itself. So this is the reason you get that error.

So if you want to use your code, you could do:

df = DataFrame(eval(data))

But better would be to not create the string in the first place, but directly putting it in a dict. Something roughly like:

data = []
for row in result_set:
    data.append({'value': row["tag_expression"], 'key': row["tag_name"]})

But probably even this is not needed, as depending on what is exactly in your result_set you could probably:

  • provide this directly to a DataFrame: DataFrame(result_set)
  • or use the pandas read_sql_query function to do this for you (see docs on this)

Java to Jackson JSON serialization: Money fields

I'm one of the maintainers of jackson-datatype-money, so take this answer with a grain of salt since I'm certainly biased. The module should cover your needs and it's pretty light-weight (no additional runtime dependencies). In addition it's mentioned in the Jackson docs, Spring docs and there were even some discussions already about how to integrate it into the official ecosystem of Jackson.

How can I set size of a button?

Try with setPreferredSize instead of setSize.

UPDATE: GridLayout take up all space in its container, and BoxLayout seams to take up all the width in its container, so I added some glue-panels that are invisible and just take up space when the user stretches the window. I have just done this horizontally, and not vertically, but you could implement that in the same way if you want it.

Since GridLayout make all cells in the same size, it doesn't matter if they have a specified size. You have to specify a size for its container instead, as I have done.

import javax.swing.*;
import java.awt.*;

public class PanelModel {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Colored Trails");

        JPanel mainPanel = new JPanel();
        mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.Y_AXIS));

        JPanel firstPanel = new JPanel(new GridLayout(4, 4));
        firstPanel.setPreferredSize(new Dimension(4*100, 4*100));
        for (int i=1; i<=4; i++) {
            for (int j=1; j<=4; j++) {
                firstPanel.add(new JButton());

        JPanel firstGluePanel = new JPanel(new BorderLayout());
        firstGluePanel.add(firstPanel, BorderLayout.WEST);
        firstGluePanel.add(Box.createHorizontalGlue(), BorderLayout.CENTER);
        firstGluePanel.add(Box.createVerticalGlue(), BorderLayout.SOUTH);

        JPanel secondPanel = new JPanel(new GridLayout(13, 5));
        secondPanel.setPreferredSize(new Dimension(5*40, 13*40));
        for (int i=1; i<=5; i++) {
            for (int j=1; j<=13; j++) {
                secondPanel.add(new JButton());

        JPanel secondGluePanel = new JPanel(new BorderLayout());
        secondGluePanel.add(secondPanel, BorderLayout.WEST);
        secondGluePanel.add(Box.createHorizontalGlue(), BorderLayout.CENTER);
        secondGluePanel.add(Box.createVerticalGlue(), BorderLayout.SOUTH);



Twitter - How to embed native video from someone else's tweet into a New Tweet or a DM

I eventually figured out an easy way to do it:

  1. On your Twitter feed, click the date/time of the tweet containing the video. That will open the single tweet view
  2. Look for the down-pointing arrow at the top-right corner of the tweet, click it to open drop-down menue
  3. Select the "Embed Video" option and copy the HTML embed code and Paste it to Notepad
  4. Find the last "" shortened URL inside the HTML code (should be something like this: https://`` Copy this URL and paste it in a new browser tab.
  5. The browser will expand the shortened URL to something which looks like this:

This is the link to the Twitter Card containing the native video. Pasting this link in a new tweet or DM will include the native video in it!

Simple dictionary in C++

Until I was really concerned about performance, I would use a function, that takes a base and returns its match:

char base_pair(char base)
    switch(base) {
        case 'T': return 'A';
        ... etc
        default: // handle error

If I was concerned about performance, I would define a base as one fourth of a byte. 0 would represent A, 1 would represent G, 2 would represent C, and 3 would represent T. Then I would pack 4 bases into a byte, and to get their pairs, I would simply take the complement.

What version of javac built my jar?

I as well wrote my own bash script to dump the Java version required by all the jars passed at the command line... Mine is a bit rough, but works for me ;-)

example usage

$ *.jar
JVM VERSION REQUIRED: 46.0, /private/tmp/jars/WEB-INF/lib/json-simple-1.1.jar
JVM VERSION REQUIRED: 49.0, /private/tmp/jars/WEB-INF/lib/json-smart-1.1.1.jar
JVM VERSION REQUIRED: 50.0, /private/tmp/jars/WEB-INF/lib/jsontoken-1.0.jar
JVM VERSION REQUIRED: 50.0, /private/tmp/jars/WEB-INF/lib/jsr166y-1.7.0.jar


function show_help()
  ME=$(basename $0)
  IT=$(cat <<EOF

  Dumps the version of the JVM required to run the classes in a jar file

  usage: $ME JAR_FILE


  $ME myFile.jar    ->  VERSION: 50.0     myFile.jar

  Java versions are:
  54 = Java 10
  53 = Java 9
  52 = Java 8
  51 = Java 7
  50 = Java 6
  49 = Java 5
  48 = Java 1.4
  47 = Java 1.3
  46 = Java 1.2
  45.3 = Java 1.1

  echo "$IT"

if [ "$1" == "help" ]
if [ -z "$1" ]

function unzipJarToTmp()
  CLASS_FILE=$(jar -tf "$JAR" | grep \.class$ | grep -v '\$' | head -n1 | awk '{print $NF}')
  jar xf "$JAR" "$CLASS_FILE"

  MAJOR=$(javap -v "$OUT_FILE" 2>&1 | grep major | awk -F' ' '{print $3'})
  MINOR=$(javap -v "$OUT_FILE" 2>&1 | grep minor | awk -F' ' '{print $3'})
  if [ -z "$MAJOR" ]
    echo "JVM VERSION REQUIRED: NA as no classes in $JAR"

# loop over cmd line args
for JAR in "$@"
  cd "$DIR"
  JAR_UID=$(basename "$JAR" | sed s/.jar//g)
  mkdir -p "$TMPDIR"
  JAR_ABS_PATH=$(realpath $JAR)

  cd "$TMPDIR"

  #echo "$JAR_ABS_PATH"
  unzipJarToTmp "$JAR_ABS_PATH"
  #sleep 2

cat, grep and cut - translated to python

You need to have better understanding of the python language and its standard library to translate the expression

cat "$filename": Reads the file cat "$filename" and dumps the content to stdout

|: pipe redirects the stdout from previous command and feeds it to the stdin of the next command

grep "something": Searches the regular expressionsomething plain text data file (if specified) or in the stdin and returns the matching lines.

cut -d'"' -f2: Splits the string with the specific delimiter and indexes/splices particular fields from the resultant list

Python Equivalent

cat "$filename"  | with open("$filename",'r') as fin:        | Read the file Sequentially
                 |     for line in fin:                      |   
grep 'something' | import re                                 | The python version returns
                 | line = re.findall(r'something', line)[0]  | a list of matches. We are only
                 |                                           | interested in the zero group
cut -d'"' -f2    | line = line.split('"')[1]                 | Splits the string and selects
                 |                                           | the second field (which is
                 |                                           | index 1 in python)


import re
with open("filename") as origin_file:
    for line in origin_file:
        line = re.findall(r'something', line)
        if line:
           line = line[0].split('"')[1]
        print line

exception in thread 'main' java.lang.NoClassDefFoundError:

I spent four hours trying various permutations & search suggestions.

At last, found this post that worked but not the best solution to change the original code to test it.

  1. Tried changing CLASSPATH, to include class libraries, set classpath=JDKbin;JDKlib;JREbin;JRElib;myClassLib;.
  2. Changed the current directory to parent directory(package folder) and tired java <packageName>.<className> also tried the java ..\<packageName>.<className>

Neither worked.

However first response alone worked. Thank you so much Abhi!!!

"I found one another common reason. If you create the java file inside a package using IDE like eclipse, you will find the package name on the top of your java file like "package pkgName". If you try to run this file from command prompt, you will get the NoClassDefFoundError error. Remove the package name from the java file and use the commands in the command prompt. Wasted 3 hours for this. -- Abhi"

Curious if there is any other way to make it work without having to change the original code? Thank you!

Passing an Object from an Activity to a Fragment

To pass an object to a fragment, do the following:

First store the objects in Bundle, don't forget to put implements serializable in class.

            CategoryRowFragment fragment = new CategoryRowFragment();

            // pass arguments to fragment
            Bundle bundle = new Bundle();

            // event list we want to populate
            bundle.putSerializable("eventsList", eventsList);

            // the description of the row
            bundle.putSerializable("categoryRow", categoryRow);


Then retrieve bundles in Fragment

       // events that will be populated in this row_x000D_
        mEventsList = (ArrayList<Event>)getArguments().getSerializable("eventsList");_x000D_
        // description of events to be populated in this row_x000D_
        mCategoryRow = (CategoryRow)getArguments().getSerializable("categoryRow");

How to loop through an array of objects in swift

You can try using the simple NSArray in syntax for iterating over the array in swift which makes for shorter code. The following is working for me:

class ModelAttachment {
    var id: String?
    var url: String?
    var thumb: String?

var modelAttachementObj = ModelAttachment() = "1"
modelAttachementObj.url = ""
modelAttachementObj.thumb = "thumb"

var imgs: Array<ModelAttachment> = [modelAttachementObj]

for img in imgs  {
    let url = img.url

See docs here

Regular expression for a string that does not start with a sequence

You could use a negative look-ahead assertion:


Or a negative look-behind assertion:


Or just plain old character sets and alternations:


Google Maps Android API v2 Authorization failure

Today I faced with this problem. I used Android Studio 2.1.3, windows 10. While debugging it works fine, but if I update to release mode it does not work. I cleared all proguard conditions, updated, but this was not solution.

The solution is related with project structure. The google_maps_api.xml file was different between app\src\debug\res and app\src\release\res. I did manual copy paste from debug to release folder.

Now it works.

Blurry text after using CSS transform: scale(); in Chrome

Sunderls lead me to the answer. Except filter: scale does not exist, but filter: blur does.

Apply the next declarations to the elements that appear blurred (in my case they were inside a transformed element):

backface-visibility: hidden;    
-webkit-filter: blur(0);

It almost worked perfectly. "Almost" because i'm using a transition and while in transition, elements don't look perfect, but once the transition is done, they do.

grep from tar.gz without extracting [faster one]

If this is really slow, I suspect you're dealing with a large archive file. It's going to uncompress it once to extract the file list, and then uncompress it N times--where N is the number of files in the archive--for the grep. In addition to all the uncompressing, it's going to have to scan a fair bit into the archive each time to extract each file. One of tar's biggest drawbacks is that there is no table of contents at the beginning. There's no efficient way to get information about all the files in the archive and only read that portion of the file. It essentially has to read all of the file up to the thing you're extracting every time; it can't just jump to a filename's location right away.

The easiest thing you can do to speed this up would be to uncompress the file first (gunzip file.tar.gz) and then work on the .tar file. That might help enough by itself. It's still going to loop through the entire archive N times, though.

If you really want this to be efficient, your only option is to completely extract everything in the archive before processing it. Since your problem is speed, I suspect this is a giant file that you don't want to extract first, but if you can, this will speed things up a lot:

tar zxf file.tar.gz
for f in hopefullySomeSubdir/*; do
  grep -l "string" $f

Note that grep -l prints the name of any matching file, quits after the first match, and is silent if there's no match. That alone will speed up the grepping portion of your command, so even if you don't have the space to extract the entire archive, grep -l will help. If the files are huge, it will help a lot.

How remove border around image in css?

Here's how I got rid of mine:

.main .row .thumbnail {
    display: inline-block;
    border: 0px;
    background-color: transparent;

"Couldn't read dependencies" error with npm

My mistake was the I named the file packages.json instead of package.json

How to configure Eclipse build path to use Maven dependencies?

I'm assuming you are using m2eclipse as you mentioned it. However it is not clear whether you created your project under Eclipse or not so I'll try to cover all cases.

  1. If you created a "Java" project under Eclipse (Ctrl+N > Java Project), then right-click the project in the Package Explorer view and go to Maven > Enable Dependency Management (depending on the initial project structure, you may have modify it to match the maven's one, for example by adding src/java to the source folders on the build path).

  2. If you created a "Maven Project" under Eclipse (Ctrl+N > Maven Project), then it should be already "Maven ready".

  3. If you created a Maven project outside Eclipse (manually or with an archetype), then simply import it in Eclipse (right-click the Package Explorer view and select Import... > Maven Projects) and it will be "Maven ready".

Now, to add a dependency, either right-click the project and select Maven > Add Dependency) or edit the pom manually.

PS: avoid using the maven-eclipse-plugin if you are using m2eclipse. There is absolutely no need for it, it will be confusing, it will generate some mess. No, really, don't use it unless you really know what you are doing.

In Java, how do I get the difference in seconds between 2 dates?

That should do it:

Date a = ...;
Date b = ...;


Here the relevant documentation: Date.getTime(). Be aware that this will only work for dates after January 1, 1970, 00:00:00 GMT

Use of exit() function

exit(int code); is declared in stdlib.h so you need an

#include <stdlib.h>

- You have no parameter for the exit(), it requires an int so provide one.
- Burn this book, it uses goto which is (for everyone but linux kernel hackers) bad, very, very, VERY bad.

Oh, and

void main()

is bad, too, it's:

int main(int argc, char *argv[])

nano error: Error opening terminal: xterm-256color

I can confirm this is a terminfo issue. This is what worked for me. SSH in to the remote machine and run

 sudo apt-get install ncurses-term

Boom. Problem solved.

Smooth scroll to specific div on click


$("button").click(function() {
        scrollTop: $(".second").offset().top},

Updated Jsfiddle

How to make a form close when pressing the escape key?

Paste this code into the "On Key Down" Property of your form, also make sure you set "Key Preview" Property to "Yes".

If KeyCode = vbKeyEscape Then DoCmd.Close acForm, "YOUR FORM NAME"

org.json.simple cannot be resolved

Try importing this in build.gradle dependencies

compile group: 'com.googlecode.json-simple', name: 'json-simple', version: '1.1'

SQL Server "AFTER INSERT" trigger doesn't see the just-inserted row

UPDATE: DELETE from a trigger works on both MSSql 7 and MSSql 2008.

I'm no relational guru, nor a SQL standards wonk. However - contrary to the accepted answer - MSSQL deals just fine with both recursive and nested trigger evaluation. I don't know about other RDBMSs.

The relevant options are 'recursive triggers' and 'nested triggers'. Nested triggers are limited to 32 levels, and default to 1. Recursive triggers are off by default, and there's no talk of a limit - but frankly, I've never turned them on, so I don't know what happens with the inevitable stack overflow. I suspect MSSQL would just kill your spid (or there is a recursive limit).

Of course, that just shows that the accepted answer has the wrong reason, not that it's incorrect. However, prior to INSTEAD OF triggers, I recall writing ON INSERT triggers that would merrily UPDATE the just inserted rows. This all worked fine, and as expected.

A quick test of DELETEing the just inserted row also works:

 CREATE TABLE Test ( Id int IDENTITY(1,1), Column1 varchar(10) )


 --SCOPE_IDENTITY() should be the same, but doesn't exist in SQL 7
 PRINT @@IDENTITY --Will print 1. Run it again, and it'll print 2, 3, etc.

 SELECT * FROM Test --No rows

You have something else going on here.

Call an activity method from a fragment

For Kotlin try it out

class DataForm : Fragment() {
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {

    fun getResponse(response: String) {
        // code

class Tasks(private val context: Any) {
    fun getData() {

        val getContext = (context as DataForm).activity
        val getFragment = (context as DataForm)

        val responseListener = Response.Listener<String> { response ->

        val errorListener = Response.ErrorListener { error ->

        val stringRequest = StringRequest(Request.Method.GET, url, responseListener, errorListener)

How to convert integer to decimal in SQL Server query?

select cast (height as decimal)/10 as HeightDecimal


import java.util.ArrayList;
import java.util.List;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

public class Employee implements Serializable{
private static final long serialVersionUID = 1L;
private int id;
private String empName;

List<Address> addList=new ArrayList<Address>();

public int getId() {
    return id;
public void setId(int id) { = id;
public String getEmpName() {
    return empName;
public void setEmpName(String empName) {
    this.empName = empName;

public List<Address> getAddList() {
    return addList;

public void setAddList(List<Address> addList) {
    this.addList = addList;

We have two entities Employee and Address with One to Many relationship.

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

public class Address implements Serializable{

private static final long serialVersionUID = 1L;

private int address_id;
private String address;
Employee employee;

public int getAddress_id() {
    return address_id;
public void setAddress_id(int address_id) {
    this.address_id = address_id;
public String getAddress() {
    return address;
public void setAddress(String address) {
    this.address = address;

public Employee getEmployee() {
    return employee;
public void setEmployee(Employee employee) {
    this.employee = employee;

By this way we can implement inner join between two tables

import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;

public class Main {

public static void main(String[] args) {



private static void saveEmployee() {
    Employee employee=new Employee();
    Employee employee1=new Employee();
    Employee employee2=new Employee();
    Employee employee3=new Employee();

    Address address=new Address();
    Address address1=new Address();
    Address address2=new Address();
    Address address3=new Address();

    address.setAddress("1485,Sector 42 b");
    address1.setAddress("1485,Sector 42 c");
    address2.setAddress("1485,Sector 42 d");
    address3.setAddress("1485,Sector 42 a");




    Session session=HibernateUtil.getSessionFactory().openSession();


private static void retrieveEmployee() {

    String sqlQuery="select e from Employee e inner join e.addList";

    Session session=HibernateUtil.getSessionFactory().openSession();

    Query query=session.createQuery(sqlQuery);

    List<Employee> list=query.list();>{System.out.println(p.getEmpName());});     
    }catch(Exception e){

I have used Java 8 for loop for priting the names. Make sure you have jdk 1.8 with tomcat 8. Also add some more records for better understanding.

 public class HibernateUtil {
 private static SessionFactory sessionFactory ;
 static {
    Configuration configuration = new Configuration();

    configuration.setProperty("hibernate.connection.url", "jdbc:mysql://localhost:3306/hibernate");                                
    configuration.setProperty("hibernate.connection.username", "root");     
    configuration.setProperty("hibernate.connection.password", "root");
    configuration.setProperty("dialect", "org.hibernate.dialect.MySQLDialect");
    configuration.setProperty("", "update");
    configuration.setProperty("hibernate.show_sql", "true");
    configuration.setProperty(" hibernate.connection.pool_size", "10");

   // configuration
    StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
    sessionFactory = configuration.buildSessionFactory(;
public static SessionFactory getSessionFactory() {
    return sessionFactory;

How to pass Multiple Parameters from ajax call to MVC Controller

You're making an HTTP POST, but trying to pass parameters with the GET query string syntax. In a POST, the data are passed as named parameters and do not use the param=value&foo=bar syntax. Using jQuery's ajax method lets you create a javascript object with the named parameters, like so:

  url: '/Home/SaveChart',
  type: 'POST',
  async: false,
  dataType: 'text',
  processData: false,    
  data: { 
      input: JSON.stringify(, 
      name: $("#wrkname").val()
  success: function (data) { }

EXEC sp_executesql with multiple parameters

Here is a simple example:

EXEC sp_executesql @sql, N'@p1 INT, @p2 INT, @p3 INT', @p1, @p2, @p3;

Your call will be something like this

EXEC sp_executesql @statement, N'@LabID int, @BeginDate date, @EndDate date, @RequestTypeID varchar', @LabID, @BeginDate, @EndDate, @RequestTypeID

C# Telnet Library

I ended up finding MinimalistTelnet and adapted it to my uses. I ended up needing to be able to heavily modify the code due to the unique** device that I am attempting to attach to.

** Unique in this instance can be validly interpreted as brain-dead.

How to concat string + i?

according to this it looks like you have to set "N" before trying to use it and it looks like it needs to be an int not string? Don't know much bout MatLab but just what i gathered from that site..hope it helps :)

Proper way to get page content

A simple, fast way to get the content by id :

echo get_post_field('post_content', $id);

And if you want to get the content formatted :

echo apply_filters('the_content', get_post_field('post_content', $id));

Works with pages, posts & custom posts.

Using Linq to group a list of objects into a new grouped list of list of objects

Still an old one, but answer from Lee did not give me the group.Key as result. Therefore, I am using the following statement to group a list and return a grouped list:

public IOrderedEnumerable<IGrouping<string, User>> groupedCustomerList;

groupedCustomerList =
        from User in userList
        group User by User.GroupID into newGroup
        orderby newGroup.Key
        select newGroup;

Each group now has a key, but also contains an IGrouping which is a collection that allows you to iterate over the members of the group.

PHP Warning: mysqli_connect(): (HY000/2002): Connection refused

In my case I was using XAMPP, and there was a log that told me the error. To find it, go to the XAMPP control panel, and click "Configure" for MySQL, then click on "Open Log."

The most current data of the log is at the bottom, and the log is organized by date, time, some number, and text in brackets that may say "Note" or "Error." One that says "Error" is likely causing the issue.

For me, my error was a tablespace that was causing an issue, so I deleted the database files at the given location.

Note: The tablespace files for your installation of XAMPP may be at a different location, but they were in /opt/lampp/var/mysql for me. I think that's typical of XAMPP on Debian-based distributions. Also, my instructions on what to click in the control panel to see the log may be a bit different for you because I'm running XAMPP on an Ubuntu-based distribution of Linux (Feren OS).