Programs & Examples On #Vector graphics

Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon(s), which are all based on mathematical equations, to represent images in computer graphics. Images are drawn at run-time from the information stored, and so vector images do not get distorted after zoom/resize etc.

SVG rounded corner

You are using a path element, why don't you just give the path a curve? See here for how to make curves using path elements:

Change fill color on vector asset in Android Studio

Add this library to the Gradle to enable color vector drawable in old android Devices.

compile ''

and re sync gradle. I think it will solve the problem.

Do I use <img>, <object>, or <embed> for SVG files?

The best option is to use SVG Images on different devices :)

<img src="your-svg-image.svg" alt="Your Logo Alt" onerror="this.src='your-alternative-image.png'">

How to enable or disable an anchor using jQuery?

Disable or Enable any element with the disabled property.

// Disable 
$("#myAnchor").prop( "disabled", true );

// Enable
$( "#myAnchor" ).prop( "disabled", false );

Check if XML Element exists

You can validate that and much more by using an XML schema language, like XSD.

If you mean conditionally, within code, then XPath is worth a look as well.

Open soft keyboard programmatically

I used it as singleton like:

public static void showSoftKeyboard(final Context context, final EditText editText) {
        try {
                    new Runnable() {
                        public void run() {
                            InputMethodManager keyboard = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE);
                            keyboard.showSoftInput(editText, 0);
                    , 200);
        } catch (NullPointerException npe) {
        } catch (Exception e) {

Use it in your activity like:

showSoftKeyboard(this, yourEditTextToFocus);

jQuery preventDefault() not triggered

Try this one:

   $("div.subtab_left li.notebook a").click(function(e) {
    return false;   

Looping through rows in a DataView

//You can convert DataView to Table. using DataView.ToTable();

foreach (DataRow drGroup in dtGroups.Rows)
    dtForms.DefaultView.RowFilter = "ParentFormID='" + drGroup["FormId"].ToString() + "'";

    if (dtForms.DefaultView.Count > 0)
        foreach (DataRow drForm in dtForms.DefaultView.ToTable().Rows)
            drNew = dtNew.NewRow();

            drNew["FormId"] = drForm["FormId"];
            drNew["FormCaption"] = drForm["FormCaption"];
            drNew["GroupName"] = drGroup["GroupName"];

// Or You Can Use

// 2.

dtForms.DefaultView.RowFilter = "ParentFormID='" + drGroup["FormId"].ToString() + "'";

DataTable DTFormFilter = dtForms.DefaultView.ToTable();

foreach (DataRow drFormFilter in DTFormFilter.Rows)
                            //Your logic goes here

How to grep with a list of words

You need to use the option -f:

$ grep -f A B

The option -F does a fixed string search where as -f is for specifying a file of patterns. You may want both if the file only contains fixed strings and not regexps.

$ grep -Ff A B

You may also want the -w option for matching whole words only:

$ grep -wFf A B

Read man grep for a description of all the possible arguments and what they do.

Duplicate line in Visual Studio Code


Duplicate Line Down : Ctrl + Shift + D

How to include view/partial specific styling in AngularJS

I know this question is old now, but after doing a ton of research on various solutions to this problem, I think I may have come up with a better solution.

UPDATE 1: Since posting this answer, I have added all of this code to a simple service that I have posted to GitHub. The repo is located here. Feel free to check it out for more info.

UPDATE 2: This answer is great if all you need is a lightweight solution for pulling in stylesheets for your routes. If you want a more complete solution for managing on-demand stylesheets throughout your application, you may want to checkout Door3's AngularCSS project. It provides much more fine-grained functionality.

In case anyone in the future is interested, here's what I came up with:

1. Create a custom directive for the <head> element:

app.directive('head', ['$rootScope','$compile',
    function($rootScope, $compile){
        return {
            restrict: 'E',
            link: function(scope, elem){
                var html = '<link rel="stylesheet" ng-repeat="(routeCtrl, cssUrl) in routeStyles" ng-href="{{cssUrl}}" />';
                scope.routeStyles = {};
                $rootScope.$on('$routeChangeStart', function (e, next, current) {
                    if(current && current.$$route && current.$$route.css){
                            current.$$route.css = [current.$$route.css];
                        angular.forEach(current.$$route.css, function(sheet){
                            delete scope.routeStyles[sheet];
                    if(next && next.$$route && next.$$route.css){
                            next.$$route.css = [next.$$route.css];
                        angular.forEach(next.$$route.css, function(sheet){
                            scope.routeStyles[sheet] = sheet;

This directive does the following things:

  1. It compiles (using $compile) an html string that creates a set of <link /> tags for every item in the scope.routeStyles object using ng-repeat and ng-href.
  2. It appends that compiled set of <link /> elements to the <head> tag.
  3. It then uses the $rootScope to listen for '$routeChangeStart' events. For every '$routeChangeStart' event, it grabs the "current" $$route object (the route that the user is about to leave) and removes its partial-specific css file(s) from the <head> tag. It also grabs the "next" $$route object (the route that the user is about to go to) and adds any of its partial-specific css file(s) to the <head> tag.
  4. And the ng-repeat part of the compiled <link /> tag handles all of the adding and removing of the page-specific stylesheets based on what gets added to or removed from the scope.routeStyles object.

Note: this requires that your ng-app attribute is on the <html> element, not on <body> or anything inside of <html>.

2. Specify which stylesheets belong to which routes using the $routeProvider:

app.config(['$routeProvider', function($routeProvider){
        .when('/some/route/1', {
            templateUrl: 'partials/partial1.html', 
            controller: 'Partial1Ctrl',
            css: 'css/partial1.css'
        .when('/some/route/2', {
            templateUrl: 'partials/partial2.html',
            controller: 'Partial2Ctrl'
        .when('/some/route/3', {
            templateUrl: 'partials/partial3.html',
            controller: 'Partial3Ctrl',
            css: ['css/partial3_1.css','css/partial3_2.css']

This config adds a custom css property to the object that is used to setup each page's route. That object gets passed to each '$routeChangeStart' event as .$$route. So when listening to the '$routeChangeStart' event, we can grab the css property that we specified and append/remove those <link /> tags as needed. Note that specifying a css property on the route is completely optional, as it was omitted from the '/some/route/2' example. If the route doesn't have a css property, the <head> directive will simply do nothing for that route. Note also that you can even have multiple page-specific stylesheets per route, as in the '/some/route/3' example above, where the css property is an array of relative paths to the stylesheets needed for that route.

3. You're done Those two things setup everything that was needed and it does it, in my opinion, with the cleanest code possible.

Hope that helps someone else who might be struggling with this issue as much as I was.

Are loops really faster in reverse?

In very simple words

"i-- and i++. Actually, they're both takes the same time".

but in this case when you have incremental operation.. processor evaluate the .length every time variable is incremented by 1 and in case of decrement.. particularly in this case, it will evaluate .length only once till we get 0.

How to iterate through range of Dates in Java?

private static void iterateBetweenDates(Date startDate, Date endDate) {
    Calendar startCalender = Calendar.getInstance();
    Calendar endCalendar = Calendar.getInstance();

    for(; startCalender.compareTo(endCalendar)<=0;
          startCalender.add(Calendar.DATE, 1)) {
        // write your main logic here


RSpec: how to test if a method was called?

To fully comply with RSpec ~> 3.1 syntax and rubocop-rspec's default option for rule RSpec/MessageSpies, here's what you can do with spy:

Message expectations put an example's expectation at the start, before you've invoked the code-under-test. Many developers prefer using an arrange-act-assert (or given-when-then) pattern for structuring tests. Spies are an alternate type of test double that support this pattern by allowing you to expect that a message has been received after the fact, using have_received.

# arrange.
invitation = spy('invitation')

# act.
invitation.deliver("[email protected]")

# assert.
expect(invitation).to have_received(:deliver).with("[email protected]")

If you don't use rubocop-rspec or using non-default option. You may, of course, use RSpec 3 default with expect.

dbl = double("Some Collaborator")
expect(dbl).to receive(:foo).with("[email protected]")

How to get the file ID so I can perform a download of a file from Google Drive API on Android?

If you know the the name of the file and if you always want to download that specific file, then you can easily get the ID and other attributes for your desired file from: (towards the bottom you will find a way to run queries). In the q field enter title = 'your_file_name' and run it. You should see some result show up right below and within it should be an "id" field. That is the id you are looking for.

You can also play around with additional parameters from:

How can I compare two strings in java and define which of them is smaller than the other alphabetically?

If you would like to ignore case you could use the following:

String s = "yip";
String best = "yodel";
int compare = s.compareToIgnoreCase(best);
if(compare < 0){
    //-1, --> s is less than best. ( s comes alphabetically first)
else if(compare > 0 ){
// best comes alphabetically first.
    // strings are equal.

Laravel 5.2 - Use a String as a Custom Primary Key for Eloquent Table becomes 0

I was using Postman to test my Laravel API.

I received an error that stated

"SQLSTATE[42S22]: Column not found: 1054 Unknown column" because Laravel was trying to automatically create two columns "created_at" and "updated_at".

I had to enter public $timestamps = false; to my model. Then, I tested again with Postman and saw that an "id" = 0 variable was being created in my database.

I finally had to add public $incrementing false; to fix my API.

array filter in python?

If the order is not important, you should use set.difference. However, if you want to retain order, a simple list comprehension is all it takes.

result = [a for a in A if a not in subset_of_A]

EDIT: As delnan says, performance will be substantially improved if subset_of_A is an actual set, since checking for membership in a set is O(1) as compared to O(n) for a list.

A = [6, 7, 8, 9, 10, 11, 12]
subset_of_A = set([6, 9, 12]) # the subset of A

result = [a for a in A if a not in subset_of_A]

Bootstrap: How do I identify the Bootstrap version?

The easiest would be to locate the bootstrap file (bootstrap.css OR bootstrap.min.css) and read through the docblock, you'll see something like this

Bootstrap v3.3.6 (

How can I make a CSS glass/blur effect work for an overlay?

Here is an example that uses svg filter.

The idea is to use an svg element with height same as the #overlay and apply the feGaussianblur filter on it. This filter is applied on an svg image element. To give it an extruded effect, you could use a box-shadow at the bottom of the overlay.

Browser Support for svg filters.

Demo on Codepen

body {
  background: #222222;
#container {
  position: relative;
  width: 450px;
  margin: 0 auto;
img {
  height: 300px;
#overlay {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  z-index: 1;
  color: rgba(130, 130, 130, 0.5);
  font-size: 50px;
  text-align: center;
  line-height: 100px;
  box-shadow: 0 3px 5px rgba(0, 0, 0, 0.3);
<div id="container">
  <img src="" />
  <div id="overlay">WET</div>
  <svg width="450" height="100" viewBox="0 0 450 100" style="position: absolute; top: 0;">
      <filter id="blur">
        <feGaussianBlur in="SourceGraphic" stdDeviation="3" />
    <image filter="url(#blur)" xlink:href="" x="0" y="0" height="300px" width="450px" />

Issue pushing new code in Github

I got this error on Azure Git, and this solves the problem:

git fetch
git pull
git push --no-verify

How to get the Android Emulator's IP address?

If you do truly want the IP assigned to your emulator:

adb shell
ifconfig eth0

Which will give you something like:

eth0: ip mask flags [up broadcast running multicast]

How to allow download of .json file with ASP.NET

If you want to manually add support to your site, you can just add the following to your web.config in the system.webServer section:

    <mimeMap fileExtension=".json" mimeType="application/json" />

This will add a "local" configuration under IIS. This does not work in IIS6, but does work in IIS7 and newer.

How do I install Eclipse with C++ in Ubuntu 12.10 (Quantal Quetzal)?

I was in the same boat. Installed Eclipse, realized need CDT.

sudo apt-get install eclipse eclipse-cdt g++

This just adds the CDT package on top of existing installation - no un-installation etc. required.

What are the git concepts of HEAD, master, origin?

HEAD is not the latest revision, it's the current revision. Usually, it's the latest revision of the current branch, but it doesn't have to be.

master is a name commonly given to the main branch, but it could be called anything else (or there could be no main branch).

origin is a name commonly given to the main remote. remote is another repository that you can pull from and push to. Usually it's on some server, like github.

Simplest way to detect a pinch

None of these answers achieved what I was looking for, so I wound up writing something myself. I wanted to pinch-zoom an image on my website using my MacBookPro trackpad. The following code (which requires jQuery) seems to work in Chrome and Edge, at least. Maybe this will be of use to someone else.

function setupImageEnlargement(el)
    // "el" represents the image element, such as the results of document.getElementByd('image-id')
    var img = $(el);
    $(window, 'html', 'body').bind('scroll touchmove mousewheel', function(e)
        //TODO: need to limit this to when the mouse is over the image in question

        //TODO: behavior not the same in Safari and FF, but seems to work in Edge and Chrome

        if (typeof e.originalEvent != 'undefined' && e.originalEvent != null
            && e.originalEvent.wheelDelta != 'undefined' && e.originalEvent.wheelDelta != null)
            if (e.originalEvent.wheelDelta > 0)
                // zooming
                var newW = 1.1 * parseFloat(img.width());
                var newH = 1.1 * parseFloat(img.height());
                if (newW < el.naturalWidth && newH < el.naturalHeight)
                    // Go ahead and zoom the image
                    //console.log('zooming the image');
                        "width": newW + 'px',
                        "height": newH + 'px',
                        "max-width": newW + 'px',
                        "max-height": newH + 'px'
                    // Make image as big as it gets
                    //console.log('making it as big as it gets');
                        "width": el.naturalWidth + 'px',
                        "height": el.naturalHeight + 'px',
                        "max-width": el.naturalWidth + 'px',
                        "max-height": el.naturalHeight + 'px'
            else if (e.originalEvent.wheelDelta < 0)
                // shrinking
                var newW = 0.9 * parseFloat(img.width());
                var newH = 0.9 * parseFloat(img.height());

                //TODO: I had added these data-attributes to the image onload.
                // They represent the original width and height of the image on the screen.
                // If your image is normally 100% width, you may need to change these values on resize.
                var origW = parseFloat(img.attr('data-startwidth'));
                var origH = parseFloat(img.attr('data-startheight'));

                if (newW > origW && newH > origH)
                    // Go ahead and shrink the image
                    //console.log('shrinking the image');
                        "width": newW + 'px',
                        "height": newH + 'px',
                        "max-width": newW + 'px',
                        "max-height": newH + 'px'
                    // Make image as small as it gets
                    //console.log('making it as small as it gets');
                    // This restores the image to its original size. You may want
                    //to do this differently, like by removing the css instead of defining it.
                        "width": origW + 'px',
                        "height": origH + 'px',
                        "max-width": origW + 'px',
                        "max-height": origH + 'px'

Can you animate a height change on a UITableViewCell when selected?

Swift version of Simon Lee's answer:


Keep in mind that you should modify the height properties BEFORE endUpdates().

c++ custom compare function for std::sort()

Your comparison function is not even wrong.

Its arguments should be the type stored in the range, i.e. std::pair<K,V>, not const void*.

It should return bool not a positive or negative value. Both (bool)1 and (bool)-1 are true so your function says every object is ordered before every other object, which is clearly impossible.

You need to model the less-than operator, not strcmp or memcmp style comparisons.

See StrictWeakOrdering which describes the properties the function must meet.

How to find the installed pandas version

Simplest Solution


import pandas as pd

**Its double underscore before and after the word "version".



How to use sessions in an ASP.NET MVC 4 application?

U can store any value in session like Session["FirstName"] = FirstNameTextBox.Text; but i will suggest u to take as static field in model assign value to it and u can access that field value any where in application. U don't need session. session should be avoided.

public class Employee
   public int UserId { get; set; }
   public string EmailAddress { get; set; }
   public static string FullName { get; set; }

on controller - Employee.FullName = "ABC"; Now u can access this full Name anywhere in application.

How do you fade in/out a background color using jquery?

Using jQuery only (no UI library/plugin). Even jQuery can be easily eliminated

//Color row background in HSL space (easier to manipulate fading)

var d = 1000;
for(var i=50; i<=100; i=i+0.1){ //i represents the lightness
    d  += 10;
        }, dd);    

Demo :

  • SetTimeout increases the lightness from 50% to 100%, essentially making the background white (you can choose any value depending on your color).
  • SetTimeout is wrapped in an anonymous function for it to work properly in a loop ( reason )

How to enter quotes in a Java string?

suppose ROM is string variable which equals "strval" you can simply do

String value= " \" "+ROM+" \" ";

it will be stored as

value= " "strval" ";    

Programmatically change the height and width of a UIImageView Xcode Swift

The accepted answer in Swift 3:

let screenSize: CGRect = UIScreen.main.bounds
image.frame = CGRect(x: 0, y: 0, width: 50, height: screenSize.height * 0.2)

git pull aborted with error filename too long

Solution1 - set global config, by running this command:

git config --system core.longpaths true

Solution2 - or you can edit directly your specific git config file like below:

YourRepoFolder -> .git -> config:

    repositoryformatversion = 0
    filemode = false
    longpaths = true        <-- (add this line under core section)

Solution3 - when cloning a new repository: here.

PHP - include a php file and also send query parameters

You can use $GLOBALS to solve this issue as well.

$myvar = "Hey";

include ("test.php");

echo $GLOBALS["myvar"];

How to adjust the size of y axis labels only in R?

As the title suggests that we want to adjust the size of the labels and not the tick marks I figured that I actually might add something to the question, you need to use the mtext() if you want to specify one of the label sizes, or you can just use par(cex.lab=2) as a simple alternative. Here's a more advanced mtext() example:

foo <- data.frame(X = rnorm(10), Y = rnorm(10))
plot(Y ~ X, data=foo,
     yaxt="n", ylab="", 
     xlab="Regular boring x", 
mtext("Awesome Y variable", side=2, line=2.2, cex=2)

enter image description here

You may need to adjust the line= option to get the optimal positioning of the text but apart from that it's really easy to use.

Match multiline text using regular expression

This has nothing to do with the MULTILINE flag; what you're seeing is the difference between the find() and matches() methods. find() succeeds if a match can be found anywhere in the target string, while matches() expects the regex to match the entire string.

Pattern p = Pattern.compile("xyz");

Matcher m = p.matcher("123xyzabc");
System.out.println(m.find());    // true
System.out.println(m.matches()); // false

Matcher m = p.matcher("xyz");
System.out.println(m.matches()); // true

Furthermore, MULTILINE doesn't mean what you think it does. Many people seem to jump to the conclusion that you have to use that flag if your target string contains newlines--that is, if it contains multiple logical lines. I've seen several answers here on SO to that effect, but in fact, all that flag does is change the behavior of the anchors, ^ and $.

Normally ^ matches the very beginning of the target string, and $ matches the very end (or before a newline at the end, but we'll leave that aside for now). But if the string contains newlines, you can choose for ^ and $ to match at the start and end of any logical line, not just the start and end of the whole string, by setting the MULTILINE flag.

So forget about what MULTILINE means and just remember what it does: changes the behavior of the ^ and $ anchors. DOTALL mode was originally called "single-line" (and still is in some flavors, including Perl and .NET), and it has always caused similar confusion. We're fortunate that the Java devs went with the more descriptive name in that case, but there was no reasonable alternative for "multiline" mode.

In Perl, where all this madness started, they've admitted their mistake and gotten rid of both "multiline" and "single-line" modes in Perl 6 regexes. In another twenty years, maybe the rest of the world will have followed suit.

WPF: Setting the Width (and Height) as a Percentage Value

Typically, you'd use a built-in layout control appropriate for your scenario (e.g. use a grid as a parent if you want scaling relative to the parent). If you want to do it with an arbitrary parent element, you can create a ValueConverter do it, but it probably won't be quite as clean as you'd like. However, if you absolutely need it, you could do something like this:

public class PercentageConverter : IValueConverter
    public object Convert(object value, 
        Type targetType, 
        object parameter, 
        System.Globalization.CultureInfo culture)
        return System.Convert.ToDouble(value) * 

    public object ConvertBack(object value, 
        Type targetType, 
        object parameter, 
        System.Globalization.CultureInfo culture)
        throw new NotImplementedException();

Which can be used like this, to get a child textbox 10% of the width of its parent canvas:

<Window x:Class="WpfApplication1.Window1"
    Title="Window1" Height="300" Width="300">
        <local:PercentageConverter x:Key="PercentageConverter"/>
    <Canvas x:Name="canvas">
        <TextBlock Text="Hello"
                       Converter={StaticResource PercentageConverter}, 

Difference between ProcessBuilder and Runtime.exec()

Yes there is a difference.

  • The Runtime.exec(String) method takes a single command string that it splits into a command and a sequence of arguments.

  • The ProcessBuilder constructor takes a (varargs) array of strings. The first string is the command name and the rest of them are the arguments. (There is an alternative constructor that takes a list of strings, but none that takes a single string consisting of the command and arguments.)

So what you are telling ProcessBuilder to do is to execute a "command" whose name has spaces and other junk in it. Of course, the operating system can't find a command with that name, and the command execution fails.

How to make HTML code inactive with comments

Just create a multi-line comment around it. When you want it back, just erase the comment tags.

For example, <!-- Stuff to comment out or make inactive -->

Matplotlib figure facecolor (background color)

If you want to change background color, try this:

plt.rcParams['figure.facecolor'] = 'white'

Jenkins: Is there any way to cleanup Jenkins workspace?

If you want to just remove one dir (or file) you can use Groovy and Manage Jenkins ? Scripts Console run a script which removes it.

For example, you can look at the files with:

dh = new File('./bitnami/jenkins/jenkins_home/workspace/jobname/folder')
dh.eachFile {

And then, when you have the folder you want to delete in dh, you could simply append the next code:


And it will be deleted.

Note: The path shown in the example is for a Bitnami Jenkins installation, yours could be different.

Assert that a method was called in a Python unit test

I'm not aware of anything built-in. It's pretty simple to implement:

class assertMethodIsCalled(object):
    def __init__(self, obj, method):
        self.obj = obj
        self.method = method

    def called(self, *args, **kwargs):
        self.method_called = True
        self.orig_method(*args, **kwargs)

    def __enter__(self):
        self.orig_method = getattr(self.obj, self.method)
        setattr(self.obj, self.method, self.called)
        self.method_called = False

    def __exit__(self, exc_type, exc_value, traceback):
        assert getattr(self.obj, self.method) == self.called,
            "method %s was modified during assertMethodIsCalled" % self.method

        setattr(self.obj, self.method, self.orig_method)

        # If an exception was thrown within the block, we've already failed.
        if traceback is None:
            assert self.method_called,
                "method %s of %s was not called" % (self.method, self.obj)

class test(object):
    def a(self):
        print "test"
    def b(self):

obj = test()
with assertMethodIsCalled(obj, "a"):

This requires that the object itself won't modify self.b, which is almost always true.

How do I debug error ECONNRESET in Node.js?

I had this Error too and was able to solve it after days of debugging and analysis:

my solution

For me VirtualBox (for Docker) was the Problem. I had Port Forwarding configured on my VM and the error only occured on the forwarded port.

general conclusions

The following observations may save you days of work I had to invest:

  • For me the problem only occurred on connections from localhost to localhost on one port. -> check changing any of these constants solves the problem.
  • For me the problem only occurred on my machine -> let someone else try it.
  • For me the problem only occurred after a while and couldn't be reproduced reliably
  • My Problem couldn't be inspected with any of nodes or expresses (debug-)tools. -> don't waste time on this

-> figure out if something is messing around with your network (-settings), like VMs, Firewalls etc., this is probably the cause of the problem.

Redirect form to different URL based on select option element

you can use this simple way

<select onchange="location = this.value;">
                <option value="/finished">Finished</option>
                <option value="/break">Break</option>
                <option value="/issue">Issues</option>
                <option value="/downtime">Downtime</option>

will redirect to route url you can direct to .html page or direct to some link just change value in option.

Favicon dimensions?

16x16 pixels, *.ico format.

Custom height Bootstrap's navbar

I believe you are using Bootstrap 3. If so, please try this code, here is the bootply

    <div class="navbar navbar-static-top navbar-default">
        <div class="navbar-header">
            <a class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
                <span class="glyphicon glyphicon-th-list"></span>
        <div class="container" style="background:yellow;">
            <a href="/">
                <img src="img/logo.png" class="logo img-responsive">

            <nav class="navbar-collapse collapse pull-right" style="line-height:150px; height:150px;">
                <ul class="nav navbar-nav" style="display:inline-block;">
                    <li><a href="">Portfolio</a></li>
                    <li><a href="">Blog</a></li>
                    <li><a href="">Contact</a></li>

What is the difference between MOV and LEA?

MOV can do same thing as LEA [label], but MOV instruction contain the effective address inside the instruction itself as an immediate constant (calculated in advance by the assembler). LEA uses PC-relative to calculate the effective address during the execution of the instruction.

Visual Studio 2015 or 2017 does not discover unit tests

If you are working with multiple App or Web.Config files. eg:

enter image description here

Its likely you are using a Config that is RELEASE MODE and that will strip the Debug mode setting from the config:

    <compilation xdt:Transform="RemoveAttributes(debug)" />

Change the Config to one that doesn't remove DEBUG MODE.

Select distinct using linq

myList.GroupBy(i => => group.First())

Removing spaces from a variable input using PowerShell 4.0

The Replace operator means Replace something with something else; do not be confused with removal functionality.

Also you should send the result processed by the operator to a variable or to another operator. Neither .Replace(), nor -replace modifies the original variable.

To remove all spaces, use 'Replace any space symbol with empty string'

$string = $string -replace '\s',''

To remove all spaces at the beginning and end of the line, and replace all double-and-more-spaces or tab symbols to spacebar symbol, use

$string = $string -replace '(^\s+|\s+$)','' -replace '\s+',' '

or the more native System.String method

$string = $string.Trim()

Regexp is preferred, because ' ' means only 'spacebar' symbol, and '\s' means 'spacebar, tab and other space symbols'. Note that $string.Replace() does 'Normal' replace, and $string -replace does RegEx replace, which is more heavy but more functional.

Note that RegEx have some special symbols like dot (.), braces ([]()), slashes (\), hats (^), mathematical signs (+-) or dollar signs ($) that need do be escaped. ( '' -replace '\.','-' => 'my-space-com'. A dollar sign with a number (ex $1) must be used on a right part with care

'2033' -replace '(\d+)',$( 'Data: $1')
Data: 2033

UPDATE: You can also use $str = $str.Trim(), along with TrimEnd() and TrimStart(). Read more at System.String MSDN page.

Python: Remove division decimal

if val % 1 == 0:
    val = int(val)

    val = float(val)

This worked for me.

How it works: if the remainder of the quotient of val and 1 is 0, val has to be an integer and can, therefore, be declared to be int without having to worry about losing decimal numbers.

Compare these two situations:


val = 12.00

if val % 1 == 0:
    val = int(val)
    val = float(val)


In this scenario, the output is 12, because 12.00 divided by 1 has the remainder of 0. With this information we know, that val doesn't have any decimals and we can declare val to be int.


val = 13.58

if val % 1 == 0:
    val = int(val)
    val = float(val)


This time the output is 13.58, because when val is divided by 1 there is a remainder (0.58) and therefore val is declared to be a float.

By just declaring the number to be an int (without testing the remainder) decimal numbers will be cut off.

This way there are no zeros in the end and no other than the zeros will be ignored.

ASP.NET MVC Razor pass model to layout

Let's assume your model is a collection of objects (or maybe a single object). For each object in the model do the following.

1) Put the object you want to display in the ViewBag. For example:

  ViewBag.YourObject = yourObject;

2) Add a using statement at the top of _Layout.cshtml that contains the class definition for your objects. For example:

@using YourApplication.YourClasses;

3) When you reference yourObject in _Layout cast it. You can apply the cast because of what you did in (2).

Fatal error: Can't open and lock privilege tables: Table '' doesn't exist

If you move your datadir, you not only need to give the new datadir permissions, but you need to ensure all parent directories have permission.

I moved my datadir to a hard drive, mounted in Ubuntu as:


and my datadir was Databases.

I had to set permissions to 771 to each of the media, user and Data directories:

sudo chmod 771 *DIR*

If this does not work, another way you can get mysql to work is to change user in /etc/mysql/my.cnf to root; though there are no doubt some issues with doing that from a security perspective.

Get width in pixels from element with style set with %?

This jQuery worked for me:


This will get you the computed width

if (select count(column) from table) > 0 then

not so elegant but you dont need to declare any variable:

for k in (select max(1) from table where 1 = 1) loop
    update x where column = value;
end loop;

Ping site and return result in PHP

function urlExists($url=NULL)  
    if($url == NULL) return false;  
    $ch = curl_init($url);  
    curl_setopt($ch, CURLOPT_TIMEOUT, 5);  
    curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 5);  
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);  
    $data = curl_exec($ch);  
    $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);  
    if($httpcode>=200 && $httpcode<300){  
        return true;  
    } else {  
        return false;  

This was grabbed from this post on how to check if a URL exists. Because Twitter should provide an error message above 300 when it is in maintenance, or a 404, this should work perfectly.

Portable way to check if directory exists [Windows/Linux, C]

stat() works on Linux., UNIX and Windows as well:

#include <sys/types.h>
#include <sys/stat.h>

struct stat info;

if( stat( pathname, &info ) != 0 )
    printf( "cannot access %s\n", pathname );
else if( info.st_mode & S_IFDIR )  // S_ISDIR() doesn't exist on my windows 
    printf( "%s is a directory\n", pathname );
    printf( "%s is no directory\n", pathname );

Launching Google Maps Directions via an intent on Android

Well you can try to open the built-in application Android Maps by using the Intent.setClassName method.

Intent i = new Intent(Intent.ACTION_VIEW,Uri.parse("geo:37.827500,-122.481670"));

how to change color of TextinputLayout's label and edittext underline android

<style name="Widget.Design.TextInputLayout" parent="android:Widget">
    <item name="hintTextAppearance">@style/TextAppearance.Design.Hint</item>
    <item name="errorTextAppearance">@style/TextAppearance.Design.Error</item>

You can override this style for layout

And also you can change inner EditText-item style too.

CSS position:fixed inside a positioned element

Seems, css transforms can be used

"‘transform’ property establishes a new local coordinate system at the element",

but ... this is not cross-browser, seems only Opera works correctly

Saving image to file

If you are drawing on the Graphics of the Control than you should do something draw on the Bitmap everything you are drawing on the canvas, but have in mind that Bitmap needs to be the exact size of the control you are drawing on:

  Bitmap bmp = new Bitmap(myControl.ClientRectangle.Width,myControl.ClientRectangle.Height);
  Graphics gBmp = Graphics.FromImage(bmp);
  gBmp.DrawEverything(); //this is your code for drawing
  bmp.Save("image.png", ImageFormat.Png);

Or you can use a DrawToBitmap method of the Control. Something like this:

Bitmap bmp = new Bitmap(myControl.ClientRectangle.Width, myControl.ClientRectangle.Height);
myControl.DrawToBitmap(bmp,new Rectangle(0,0,bmp.Width,bmp.Height));
bmp.Save("image.png", ImageFormat.Png);

How to convert Milliseconds to "X mins, x seconds" in Java?

    long startTime = System.currentTimeMillis();
    // do your work...
    long endTime=System.currentTimeMillis();
    long diff=endTime-startTime;       
    long hours=TimeUnit.MILLISECONDS.toHours(diff);
    long min=TimeUnit.MILLISECONDS.toMinutes(diff);
    long seconds=TimeUnit.MILLISECONDS.toSeconds(diff);
    //hour, min and seconds variables contains the time elapsed on your work

Warning: push.default is unset; its implicit value is changing in Git 2.0

I realize this is an old post but as I just ran into the same issue and had trouble finding the answer I thought I'd add a bit.

So @hammar's answer is correct. Using push.default simple is, in a way, like configuring tracking on your branches so you don't need to specify remotes and branches when pushing and pulling. The matching option will push all branches to their corresponding counterparts on the default remote (which is the first one that was set up unless you've configured your repo otherwise).

One thing I hope others find useful in the future is that I was running Git 1.8 on OS X Mountain Lion and never saw this error. Upgrading to Mavericks is what suddenly made it show up (running git --version will show git version (Apple Git-47) which I'd never seen until the update to the OS.

Adding a column to a data.frame

Approach based on identifying number of groups (x in mapply) and its length (y in mapply)

mytb<-read.table(text="h_no  h_freq  h_freqsq group
1     0.09091 0.008264628 1
2     0.00000 0.000000000 1
3     0.04545 0.002065702 1
4     0.00000 0.000000000 1  
1     0.13636 0.018594050 2
2     0.00000 0.000000000 2
3     0.00000 0.000000000 2
4     0.04545 0.002065702 2
5     0.31818 0.101238512 2
6     0.00000 0.000000000 2
7     0.50000 0.250000000 2 
1     0.13636 0.018594050 3 
2     0.09091 0.008264628 3
3     0.40909 0.167354628 3
4     0.04545 0.002065702 3", header=T, stringsAsFactors=F)


  rep(x,y),                      # repeat x number y times
  x= 1:length(positionsof1s),    # x is 1 to number of nth group = g1:g3
  y= c( diff(positionsof1s),     # y is number of repeats of groups g1 to penultimate (g2) = 4, 7
        nrow(mytb)-              # this line and the following gives number of repeat for last group (g3)
          (positionsof1s[length(positionsof1s )]-1 )  # number of rows - position of penultimate group (g2) 
      ) ) )

How to "z-index" to make a menu always on top of the content

Ok, Im assuming you want to put the .left inside the container so I suggest you edit your html. The key is the position:absolute and right:0

#right { 
    background-color: red;
    height: 300px;
    width: 300px;
    z-index: 999999;
    margin-top: 0px;
    position: absolute;

here is the full code:

Django {% with %} tags within {% if %} {% else %} tags?

Like this:

{% if age > 18 %}
    {% with patient as p %}
    <my html here>
    {% endwith %}
{% else %}
    {% with patient.parent as p %}
    <my html here>
    {% endwith %}
{% endif %}

If the html is too big and you don't want to repeat it, then the logic would better be placed in the view. You set this variable and pass it to the template's context:

p = (age > 18 && patient) or patient.parent

and then just use {{ p }} in the template.

Calculate text width with JavaScript

In case anyone else got here looking both for a way to measure the width of a string and a way to know what's the largest font size that will fit in a particular width, here is a function that builds on @Domi's solution with a binary search:

 * Find the largest font size (in pixels) that allows the string to fit in the given width.
 * @param {String} text - The text to be rendered.
 * @param {String} font - The css font descriptor that text is to be rendered with (e.g. "bold ?px verdana") -- note the use of ? in place of the font size.
 * @param {Number} width - The width in pixels the string must fit in
 * @param {Number} minFontPx - The smallest acceptable font size in pixels
 * @param {Number} maxFontPx - The largest acceptable font size in pixels
function GetTextSizeForWidth(text, font, width, minFontPx, maxFontPx) {
  for (;;) {
    var s = font.replace("?", maxFontPx);
    var w = GetTextWidth(text, s);
    if (w <= width) {
      return maxFontPx;

    var g = (minFontPx + maxFontPx) / 2;

    if (Math.round(g) == Math.round(minFontPx) || Math.round(g) == Math.round(maxFontPx)) {
      return g;

    s = font.replace("?", g);
    w = GetTextWidth(text, s);
    if (w >= width) {
      maxFontPx = g;
    } else {
      minFontPx = g;

ImportError: No Module Named bs4 (BeautifulSoup)

A lot of tutorials/references were written for Python 2 and tell you to use pip install somename. If you're using Python 3 you want to change that to pip3 install somename.

Mysql select distinct

Are you looking for "SELECT * FROM temp_tickets GROUP BY ticket_id ORDER BY ticket_id ?


(SELECT ticket_id, MAX(id) as id FROM temp_tickets GROUP BY ticket_id) a  
INNER JOIN temp_tickets t ON ( =

Command to list all files in a folder as well as sub-folders in windows

Following commands we can use for Linux or Mac. For Windows we can use below on git bash.

List all files, first level folders, and their contents

ls * -r

List all first-level subdirectories and files

file */*

Save file list to text

file */* *>> ../files.txt
file */* -r *>> ../files-recursive.txt

Get everything

find . -type f

Save everything to file

find . -type f > ../files-all.txt

How can I iterate through a string and also know the index (current position)?

I would use it-str.begin() In this particular case std::distance and operator- are the same. But if container will change to something without random access, std::distance will increment first argument until it reach second, giving thus linear time and operator- will not compile. Personally I prefer the second behaviour - it's better to be notified when you algorithm from O(n) became O(n^2)...

Redis command to get all available keys?

-->Get all keys from redis-cli

-redis> keys *

-->Get list of patterns

-redis> keys d??

This will produce keys which start by 'd' with three characters.

-redis> keys *t*

This wil get keys with matches 't' character in key

-->Count keys from command line by

-redis-cli keys * |wc -l

-->Or you can use dbsize

-redis-cli dbsize

Change text from "Submit" on input tag

<input name="submitBnt" type="submit" value="like"/>

name is useful when using $_POST in php and also in javascript as document.getElementByName('submitBnt'). Also you can use name as a CS selector like input[name="submitBnt"]; Hope this helps

set gvim font in .vimrc file

  1. Start a graphical vim session.
  2. Do :e $MYGVIMRC Enter
  3. Use the graphical font selection dialog to select a font.
  4. Type :set guifont= Tab Enter.
  5. Type G o to start a new line at the end of the file.
  6. Type Ctrl+R followed by :.

The command in step 6 will insert the contents of the : special register which contains the last ex-mode command used. Here that will be the command from step 4, which has the properly formatted font name thanks to the tab completion of the value previously set using the GUI dialog.

Conditional operator in Python?

simple is the best and works in every version.

if a>10: 

How to explicitly obtain post data in Spring MVC?

Another answer to the OP's exact question is to set the consumes content type to "text/plain" and then declare a @RequestBody String input parameter. This will pass the text of the POST data in as the declared String variable (postPayload in the following example).

Of course, this presumes your POST payload is text data (as the OP stated was the case).


    @RequestMapping(value = "/your/url/here", method = RequestMethod.POST, consumes = "text/plain")
    public ModelAndView someMethod(@RequestBody String postPayload) {    
        // ...    

Deleting rows with Python in a CSV file

You should have if row[2] != "0". Otherwise it's not checking to see if the string value is equal to 0.

Xcode stops working after set "xcode-select -switch"

You should be pointing it towards the Developer directory, not the Xcode application bundle. Run this:

sudo xcode-select --switch /Applications/

With recent versions of Xcode, you can go to Xcode ? Preferences… ? Locations and pick one of the options for Command Line Tools to set the location.

Using the value in a cell as a cell reference in a formula?


=SUM(INDIRECT(<start cell here> & ":" & <end cell here>))

JQuery html() vs. innerHTML

"This method uses the browser's innerHTML property." - jQuery API

C# find biggest number

using System;
using System.Linq;

class Program
    static void Main(string[] args)
        int[] numbers = { 3, 9, 5 };
        int biggestNumber = numbers.Max();

Where to place $PATH variable assertions in zsh?

I had similar problem (in bash terminal command was working correctly but zsh showed command not found error)


just paste whatever you were earlier pasting in ~/.bashrc to:


Swift: Display HTML data in a label or textView

Swift 3.0

var attrStr = try! NSAttributedString(
        data: "<b><i>text</i></b>".data(using: String.Encoding.unicode, allowLossyConversion: true)!,
        options: [ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType],
        documentAttributes: nil)
label.attributedText = attrStr

How to use font-family lato?

Download it from here and extract LatoOFL.rar then go to TTF and open this font-face-generator click at Choose File choose font which you want to use and click at generate then download it and then go html file open it and you see the code like this

@font-face {
        font-family: "Lato Black";
        src: url('698242188-Lato-Bla.eot');
        src: url('698242188-Lato-Bla.eot?#iefix') format('embedded-opentype'),
        url('698242188-Lato-Bla.svg#Lato Black') format('svg'),
        url('698242188-Lato-Bla.woff') format('woff'),
        url('698242188-Lato-Bla.ttf') format('truetype');
        font-weight: normal;
        font-style: normal;
    font-family: "Lato Black";
    direction: ltr;

change the src code and give the url where your this font directory placed, now you can use it at your website...

If you don't want to download it use this

<link type='text/css' href=',700' />

How to revert to origin's master branch's version of file

I've faced same problem and came across to this thread but my problem was with upstream. Below git command worked for me.


git checkout {remoteName}/{branch} -- {../path/file.js}


git checkout upstream/develop -- public/js/index.js

How to set scope property with ng-init?

Try this Code

var app = angular.module('myapp', []);
  app.controller('testController', function ($scope, $http) {
       $scope.init = function(){           

<body ng-app="myapp">_x000D_
      <div ng-controller='testController' data-ng-init="testInput='value'; init();" class="col-sm-9 col-lg-9" >_x000D_

Modify SVG fill color when being served as Background-Image

Now you can achieve this on the client side like this:

var green = '3CB54A';
var red = 'ED1F24';
var svg = '<svg version="1.1" id="Layer_1" xmlns="" xmlns:xlink="" x="0px" y="0px"  width="320px" height="100px" viewBox="0 0 320 100" enable-background="new 0 0 320 100" xml:space="preserve"> <polygon class="mystar" fill="#'+green+'" points="134.973,14.204 143.295,31.066 161.903,33.77 148.438,46.896 151.617,65.43 134.973,56.679 118.329,65.43 121.507,46.896 108.042,33.77 126.65,31.066 "/><circle class="mycircle" fill="#'+red+'" cx="202.028" cy="58.342" r="12.26"/></svg>';      
var encoded = window.btoa(svg); = "url(data:image/svg+xml;base64,"+encoded+")";

Fiddle here!

jQuery UI " $("#datepicker").datepicker is not a function"

I know that this post is quite old, but for reference I fixed this issue by updating the version of datepicker

It is worth trying that too to avoid hours of debugging.

Text that shows an underline on hover

You just need to specify text-decoration: underline; with pseudo-class :hover.


<span class="underline-on-hover">Hello world</span>


.underline-on-hover:hover {
    text-decoration: underline;

I have whipped up a working Code Pen Demo.

Python 3.6 install win32api?

Information provided by @Gord

As of September 2019 pywin32 is now available from PyPI and installs the latest version (currently version 224). This is done via the pip command

pip install pywin32

If you wish to get an older version the sourceforge link below would probably have the desired version, if not you can use the command, where xxx is the version you require, e.g. 224

pip install pywin32==xxx

This differs to the pip command below as that one uses pypiwin32 which currently installs an older (namely 223)

Browsing the docs I see no reason for these commands to work for all python3.x versions, I am unsure on python2.7 and below so you would have to try them and if they do not work then the solutions below will work.

Probably now undesirable solutions but certainly still valid as of September 2019

There is no version of specific version ofwin32api. You have to get the pywin32module which currently cannot be installed via pip. It is only available from this link at the moment.

The install does not take long and it pretty much all done for you. Just make sure to get the right version of it depending on your python version :)


Since I posted my answer there are other alternatives to downloading the win32api module.

It is now available to download through pip using this command;

pip install pypiwin32

Also it can be installed from this GitHub repository as provided in comments by @Heath

UnicodeEncodeError: 'ascii' codec can't encode character u'\xe9' in position 7: ordinal not in range(128)

You need to encode Unicode explicitly before writing to a file, otherwise Python does it for you with the default ASCII codec.

Pick an encoding and stick with it:

f.write(printinfo.encode('utf8') + '\n')

or use to create a file object that'll encode for you as you write to the file:

import io

f =, 'w', encoding='utf8')

You may want to read:

before continuing.

How to create SPF record for multiple IPs?

Yes the second syntax is fine.

Have you tried using the SPF wizard?

It can quickly generate basic and complex SPF records.

Setting paper size in FPDF

/*$mpdf = new mPDF('',    // mode - default ''
 '',    // format - A4, for example, default ''
 0,     // font size - default 0
 '',    // default font family
 15,    // margin_left
 15,    // margin right
 16,     // margin top
 16,    // margin bottom
 9,     // margin header
 9,     // margin footer
 'L');  // L - landscape, P - portrait*/

Git - deleted some files locally, how do I get them from a remote repository

Since git is a distributed VCS, your local repository contains all of the information. No downloading is necessary; you just need to extract the content you want from the repo at your fingertips.

If you haven't committed the deletion, just check out the files from your current commit:

git checkout HEAD <path>

If you have committed the deletion, you need to check out the files from a commit that has them. Presumably it would be the previous commit:

git checkout HEAD^ <path>

but if it's n commits ago, use HEAD~n, or simply fire up gitk, find the SHA1 of the appropriate commit, and paste it in.

Import functions from another js file. Javascript

From a quick glance on MDN I think you may need to include the .js at the end of your file name so the import would read import './course.js' instead of import './course'


What is the difference between Bower and npm?

Found this useful explanation from

On one hand npm was created to install modules used in a node.js environment, or development tools built using node.js such Karma, lint, minifiers and so on. npm can install modules locally in a project ( by default in node_modules ) or globally to be used by multiple projects. In large projects the way to specify dependencies is by creating a file called package.json which contains a list of dependencies. That list is recognized by npm when you run npm install, which then downloads and installs them for you.

On the other hand bower was created to manage your frontend dependencies. Libraries like jQuery, AngularJS, underscore, etc. Similar to npm it has a file in which you can specify a list of dependencies called bower.json. In this case your frontend dependencies are installed by running bower install which by default installs them in a folder called bower_components.

As you can see, although they perform a similar task they are targeted to a very different set of libraries.

How to fill Matrix with zeros in OpenCV?

How to fill Matrix with zeros in OpenCV?

To fill a pre-existing Mat object with zeros, you can use Mat::zeros()

Mat m1 = ...;
m1 = Mat::zeros(1, 1, CV_64F);

To intialize a Mat so that it contains only zeros, you can pass a scalar with value 0 to the constructor:

Mat m1 = Mat(1,1, CV_64F, 0.0);
//                        ^^^^double literal

The reason your version failed is that passing 0 as fourth argument matches the overload taking a void* better than the one taking a scalar.

Powershell: Get FQDN Hostname

Local Computer FQDN via dotNet class





Dns Methods (System.Net)

note: GetHostByName method is obsolete

Local computer FQDN via WMI query

$myFQDN=(Get-WmiObject win32_computersystem).DNSHostName+"."+(Get-WmiObject win32_computersystem).Domain
Write-Host $myFQDN


Win32_ComputerSystem class

Multiple selector chaining in jQuery?

$("#Create").find(".myClass").add("#Edit .myClass").plugin({});

Use $.fn.add to concatenate two sets.

What is the best way to tell if a character is a letter or number in Java without using regexes?

 import java.util.Scanner;
 public class v{
 public static void main(String args[]){
 Scanner in=new Scanner(;
    String str;
    int l;
    int flag=0;
    System.out.println("Enter the String:");
    char[] ch=str.toCharArray();
    for(int i=0;i<l;i++){
        if ((ch[i] >= 'a' && ch[i]<= 'z') || (ch[i] >= 'A' && ch[i] <= 'Z')){

    System.out.println("Onlt char");


How to create a new variable in a data.frame based on a condition?

One obvious and straightforward possibility is to use "if-else conditions". In that example

x <- c(1, 2, 4)
y <- c(1, 4, 5)
w <- ifelse(x <= 1, "good", ifelse((x >= 3) & (x <= 5), "bad", "fair"))
data.frame(x, y, w)

** For the additional question in the edit** Is that what you expect ?

> d1 <- c("e", "c", "a")
> d2 <- c("e", "a", "b")
> w <- ifelse((d1 == "e") & (d2 == "e"), 1, 
+    ifelse((d1=="a") & (d2 == "b"), 2,
+    ifelse((d1 == "e"), 3, 99)))
> data.frame(d1, d2, w)
  d1 d2  w
1  e  e  1
2  c  a 99
3  a  b  2

If you do not feel comfortable with the ifelse function, you can also work with the if and else statements for such applications.

How can I read a large text file line by line using Java?

What you can do is scan the entire text using Scanner and go through the text line by line. Of course you should import the following:

import java.util.Scanner;
public static void readText throws FileNotFoundException {
    Scanner scan = new Scanner(new File("samplefilename.txt"));
        String line = scan.nextLine();
        //Here you can manipulate the string the way you want

Scanner basically scans all the text. The while loop is used to traverse through the entire text.

The .hasNextLine() function is a boolean that returns true if there are still more lines in the text. The .nextLine() function gives you an entire line as a String which you can then use the way you want. Try System.out.println(line) to print the text.

Side Note: .txt is the file type text.

Reading from stdin

You can do something like this to read 10 bytes:

char buffer[10];
read(STDIN_FILENO, buffer, 10);

remember read() doesn't add '\0' to terminate to make it string (just gives raw buffer).

To read 1 byte at a time:

char ch;
while(read(STDIN_FILENO, &ch, 1) > 0)
 //do stuff

and don't forget to #include <unistd.h>, STDIN_FILENO defined as macro in this file.

There are three standard POSIX file descriptors, corresponding to the three standard streams, which presumably every process should expect to have:

Integer value   Name
       0        Standard input (stdin)
       1        Standard output (stdout)
       2        Standard error (stderr)

So instead STDIN_FILENO you can use 0.

In Linux System you can find this using following command:

$ sudo grep 'STDIN_FILENO' /usr/include/* -R | grep 'define'
/usr/include/unistd.h:#define   STDIN_FILENO    0   /* Standard input.  */

Notice the comment /* Standard input. */

How to define a default value for "input type=text" without using attribute 'value'?

A non-jQuery way would be setting the value after the document is loaded:

<input type="text" id="foo" />

    document.addEventListener('DOMContentLoaded', function(event) { 
        document.getElementById('foo').value = 'bar';

Connect to sqlplus in a shell script and run SQL scripts

For example:

sqlplus -s admin/password << EOF
whenever sqlerror exit sql.sqlcode;
set echo off 
set heading off



Removing an element from an Array (Java)

You could use commons lang's ArrayUtils.

array = ArrayUtils.removeElement(array, element) library:Javadocs

http://localhost/ not working on Windows 7. What's the problem?

Uncommenting the following line in host file worked for me,

# localhost

Regular Expression to match only alphabetic characters

If you need to include non-ASCII alphabetic characters, and if your regex flavor supports Unicode, then


would be the correct regex.

Some regex engines don't support this Unicode syntax but allow the \w alphanumeric shorthand to also match non-ASCII characters. In that case, you can get all alphabetics by subtracting digits and underscores from \w like this:


\A matches at the start of the string, \z at the end of the string (^ and $ also match at the start/end of lines in some languages like Ruby, or if certain regex options are set).

Undefined reference to `pow' and `floor'

You need to compile with the link flag -lm, like this:

gcc fib.c -lm -o fibo

This will tell gcc to link your code against the math lib. Just be sure to put the flag after the objects you want to link.

How can I let a table's body scroll but keep its head fixed in place?

What you need is :

1) have a table body of limited height as scroll occurs only when contents is bigger than the scrolling window. However tbody cannot be sized, and you have to display it as a block to do so:

tbody {
   overflow-y: auto;
   display: block;
   max-height: 10em;    // For example

2) Re-sync table header and table body columns widths as making the latter a block made it an unrelated element. The only way to do so is to simulate synchronization by enforcing the same columns width to both.

However, since tbody itself is a block now, it can no longer behave like a table. Since you still need a table behavior to display you columns correctly, the solution is to ask for each of your rows to display as individual tables:

thead {         
   display: table;  
   width: 100%;     // Fill the containing table
tbody tr {
   display: table;
   width: 100%;     // Fill the containing table

(Note that, using this technique, you won't be able to span across rows anymore).

Once that done, you can enforce column widths to have the same width in both thead and tbody. You could not that:

  • individually for each column (through specific CSS classes or inline styling), which is quite tedious to do for each table instance ;
  • uniformly for all columns (through th, td { width: 20%; } if you have 5 columns for example), which is more practical (no need to set width for each table instance) but cannot work for any columns count
  • uniformly for any columns count, through a fixed table layout.

I prefer the last option, which requires adding:

thead {
   table-layout: fixed;   // Same layout for all cells
tbody tr {
   table-layout: fixed;   // Same layout for all cells
th, td {
   width: auto;   // Same width for all cells, if table has fixed layout

See a demo here, forked from the answer to this question.

BOOLEAN or TINYINT confusion

As of MySql 5.1 version reference

BIT(M) =  approximately (M+7)/8 bytes, 
BIT(1) =  (1+7)/8 = 1 bytes (8 bits)


TINYINT(1) take 8 bits.

Could not autowire field:RestTemplate in Spring boot application

Error points directly that RestTemplate bean is not defined in context and it cannot load the beans.

  1. Define a bean for RestTemplate and then use it
  2. Use a new instance of the RestTemplate

If you are sure that the bean is defined for the RestTemplate then use the following to print the beans that are available in the context loaded by spring boot application

ApplicationContext ctx =, args);
String[] beanNames = ctx.getBeanDefinitionNames();
for (String beanName : beanNames) {

If this contains the bean by the name/type given, then all good. Or else define a new bean and then use it.

How to read user input into a variable in Bash?

Yep, you'll want to do something like this:

echo -n "Enter Fullname: " 
read fullname

Another option would be to have them supply this information on the command line. Getopts is your best bet there.

Using getopts in bash shell script to get long and short command line options

Understanding the main method of python

If you import the module (.py) file you are creating now from another python script it will not execute the code within

if __name__ == '__main__':

If you run the script directly from the console, it will be executed.

Python does not use or require a main() function. Any code that is not protected by that guard will be executed upon execution or importing of the module.

This is expanded upon a little more at

how to remove only one style property with jquery

You can also replace "-moz-user-select:none" with "-moz-user-select:inherit". This will inherit the style value from any parent style or from the default style if no parent style was defined.

How to set up tmux so that it starts up with specified windows opened?

From my "get.all" script, which I invoke each morning to run a bunch of subsequent "get.XXX" jobs to refresh the software that I track. Some of them are auto-quitting. Others require more interaction once the get has finished (like asking to build emacs).

tmux att -t get ||
tmux \
  new -s get -n capp \; \
  send-keys 'get.capp' C-m \; \
  neww -n emacs \; \
  send-keys 'get.emacs' C-m \; \
  neww -n git \; \
  send-keys 'get.git' C-m \; \
  neww -n mini \; \
  send-keys '' C-m \; \
  neww -n port \; \
  send-keys 'get.port' C-m \; \
  neww -n rakudo \; \
  send-keys 'get.rakudo' C-m \; \
  neww -n neil \; \
  send-keys 'get.neil && get.neil2 && exit' C-m \; \
  neww -n red \; \
  send-keys ' && exit' C-m \; \
  neww -n cpan \; \
  send-keys 'get.cpan && exit' C-m \; \
  selectw -t emacs

VBA (Excel) Initialize Entire Array without Looping

You can initialize the array by specifying the dimensions. For example

Dim myArray(10) As Integer
Dim myArray(1 to 10) As Integer

If you are working with arrays and if this is your first time then I would recommend visiting Chip Pearson's WEBSITE.

What does this initialize to? For example, what if I want to initialize the entire array to 13?

When you want to initailize the array of 13 elements then you can do it in two ways

Dim myArray(12) As Integer
Dim myArray(1 to 13) As Integer

In the first the lower bound of the array would start with 0 so you can store 13 elements in array. For example

myArray(0) = 1
myArray(1) = 2
myArray(12) = 13

In the second example you have specified the lower bounds as 1 so your array starts with 1 and can again store 13 values

myArray(1) = 1
myArray(2) = 2
myArray(13) = 13

Wnen you initialize an array using any of the above methods, the value of each element in the array is equal to 0. To check that try this code.

Sub Sample()
    Dim myArray(12) As Integer
    Dim i As Integer

    For i = LBound(myArray) To UBound(myArray)
        Debug.Print myArray(i)
    Next i
End Sub


Sub Sample()
    Dim myArray(1 to 13) As Integer
    Dim i As Integer

    For i = LBound(myArray) To UBound(myArray)
        Debug.Print myArray(i)
    Next i
End Sub


So, in this example every value would be 13. So if I had an array Dim myArray(300) As Integer, all 300 elements would hold the value 13

Like I mentioned, AFAIK, there is no direct way of achieving what you want. Having said that here is one way which uses worksheet function Rept to create a repetitive string of 13's. Once we have that string, we can use SPLIT using "," as a delimiter. But note this creates a variant array but can be used in calculations.

Note also, that in the following examples myArray will actually hold 301 values of which the last one is empty - you would have to account for that by additionally initializing this value or removing the last "," from sNum before the Split operation.

Sub Sample()
    Dim sNum As String
    Dim i As Integer
    Dim myArray

    '~~> Create a string with 13 three hundred times separated by comma
    '~~> 13,13,13,13...13,13 (300 times)
    sNum = WorksheetFunction.Rept("13,", 300)
    sNum = Left(sNum, Len(sNum) - 1)

    myArray = Split(sNum, ",")

    For i = LBound(myArray) To UBound(myArray)
        Debug.Print myArray(i)
    Next i
End Sub

Using the variant array in calculations

Sub Sample()
    Dim sNum As String
    Dim i As Integer
    Dim myArray

    '~~> Create a string with 13 three hundred times separated by comma
    sNum = WorksheetFunction.Rept("13,", 300)
    sNum = Left(sNum, Len(sNum) - 1)

    myArray = Split(sNum, ",")

    For i = LBound(myArray) To UBound(myArray)
        Debug.Print Val(myArray(i)) + Val(myArray(i))
    Next i
End Sub

window.location (JS) vs header() (PHP) for redirection

It depends on how and when you want to redirect the user to another page.

If you want to instantly redirect a user to another page without him seeing anything of a site in between, you should use the PHP header redirect method.

If you have a Javascript and some action of the user has to result in him entering another page, that is when you should use window.location.

The meta tag refresh is often used on download sites whenever you see these "Your download should start automatically" messages. You can let the user load a page, wait for a certain amount of time, then redirect him (e.g. to a to-be-downloaded file) without Javascript.

Phone Number Validation MVC

Try this:

[DataType(DataType.PhoneNumber, ErrorMessage = "Provided phone number not valid")]

pip installing in global site-packages instead of virtualenv

I had a similar problem on Windows. It was caused by renaming folder structures in my project within a virtualenv folder name. The paths in files didn't change but stayed as they were when virtual env was created. As Chase Ries mentioned I've changed the paths to VIRTUAL_ENV and python.exe in files

  1. ./venv/Scripts/activate.bat, set "VIRTUAL_ENV=path_to_venv\venv" 11 line in file
  2. ./venv/Scripts/Activate.ps1, $env:VIRTUAL_ENV="path_to_venv\venv" 30 line in file
  3. ./venv/Scripts/pip.exe, #!d:\path_to_env\venv\scripts\python.exe this line is at the end of a file, in my case moved to the right in 667 line, I am working on disc d so at the begining of the path is the letter of it
  4. ./venv/Scripts/pip3.7.exe, #!d:\path_to_env\venv\scripts\python.exe this line is at the end of a file, in my case moved to the right in 667 line
  5. ./venv/Scripts/pip3.exe, #!d:\path_to_env\venv\scripts\python.exe this line is at the end of a file, in my case moved to the right in 667 line

Accessing SQL Database in Excel-VBA

Add set nocount on to the beginning of the stored proc (if you're on SQL Server). I just solved this problem in my own work and it was caused by intermediate results, such as "1203 Rows Affected", being loaded into the Recordset I was trying to use.

How to change date format (MM/DD/YY) to (YYYY-MM-DD) in date picker

Just need to define yy-mm-dd here. dateFormat

Default is mm-dd-yy

Change mm-dd-yy to yy-mm-dd. Look example below

  $(function() {
    $( "#datepicker" ).datepicker({
      dateFormat: 'yy-mm-dd',
      changeMonth: true,
      changeYear: true
  } );

Date: <input type="text" id="datepicker">

Recreate the default website in IIS

Try this:

In the IIS Manager right click on Web sites, chose New, then Web site...

This way you can recreate the Default Web Site.

After these steps restart IIS: Right click on local computer, All Tasks, Restart IIS...

A KeyValuePair in Java

Android programmers could use BasicNameValuePair


BasicNameValuePair is now deprecated (API 22). Use Pair instead.

Example usage:

Pair<Integer, String> simplePair = new Pair<>(42, "Second");
Integer first = simplePair.first; // 42
String second = simplePair.second; // "Second"

Using Postman to access OAuth 2.0 Google APIs

This is an old question, but it has no chosen answer, and I just solved this problem myself. Here's my solution:

  1. Make sure you are set up to work with your Google API in the first place. See Google's list of prerequisites. I was working with Google My Business, so I also went through it's Get Started process.

  2. In the OAuth 2.0 playground, Step 1 requires you to select which API you want to authenticate. Select or input as applicable for your case (in my case for Google My Business, I had to input into the "Input your own scopes" input field). Note: this is the same as what's described in step 6 of the "Make a simple HTTP request" section of the Get Started guide.

  3. Assuming successful authentication, you should get an "Access token" returned in the "Step 1's result" step in the OAuth playground. Copy this token to your clipboard.

  4. Open Postman and open whichever collection you want as necessary.

  5. In Postman, make sure "GET" is selected as the request type, and click on the "Authorization" tab below the request type drop-down.

  6. In the Authorization "TYPE" dropdown menu, select "Bearer Token"

  7. Paste your previously copied "Access Token" which you copied from the OAuth playground into the "Token" field which displays in Postman.

  8. Almost there! To test if things work, put into the main URL input bar in Postman and click the send button. You should get a JSON list of accounts back in the response that looks something like the following:

        "accounts": [
                "name": "accounts/REDACTED",
                "accountName": "REDACTED",
                "type": "PERSONAL",
                "state": {
                    "status": "UNVERIFIED"
                "name": "accounts/REDACTED",
                "accountName": "REDACTED",
                "type": "LOCATION_GROUP",
                "role": "OWNER",
                "state": {
                    "status": "UNVERIFIED"
                "permissionLevel": "OWNER_LEVEL"

Waiting for Target Device to Come Online

Make sure you have enabled USB debugging on your device

Depending on the version of Android you're using, proceed as follows:

  • On Android 8.0 and higher, go to Settings > System > About phone and tap Build number seven times.
  • On Android 4.2 through 7.1.2, go to Settings > About phone and tap Build number seven times.

Return to the main Settings menu to find Developer options at the bottom. In the Developer options menu, scroll down and enable USB debugging.

Getting the filenames of all files in a folder

Here's how to look in the documentation.

First, you're dealing with IO, so look in the package.

There are two classes that look interesting: FileFilter and FileNameFilter. When I clicked on the first, it showed me that there was a a listFiles() method in the File class. And the documentation for that method says:

Returns an array of abstract pathnames denoting the files in the directory denoted by this abstract pathname.

Scrolling up in the File JavaDoc, I see the constructors. And that's really all I need to be able to create a File instance and call listFiles() on it. Scrolling still further, I can see some information about how files are named in different operating systems.

Why would one omit the close tag?

According to the docs, it's preferable to omit the closing tag if it's at the end of the file for the following reason:

If a file is pure PHP code, it is preferable to omit the PHP closing tag at the end of the file. This prevents accidental whitespace or new lines being added after the PHP closing tag, which may cause unwanted effects because PHP will start output buffering when there is no intention from the programmer to send any output at that point in the script.

PHP Manual > Language Reference > Basic syntax > PHP tags

How to send password using sftp batch file

You'll want to install the sshpass program. Then:


Obviously, it's better to setup public key authentication. Only use this if that's impossible to do, for whatever reason.

How do I use HTML as the view engine in Express?

I recommend using - extremely lightwave and blazingly fast template engine. The name is a bit misleading as it can work without expressjs too.

The basics required to integrate express-es6-template-engine in your app are pretty simple and quite straight forward to implement:

const express = require('express'),_x000D_
  es6Renderer = require('express-es6-template-engine'),_x000D_
  app = express();_x000D_
app.engine('html', es6Renderer);_x000D_
app.set('views', 'views');_x000D_
app.set('view engine', 'html');_x000D_
app.get('/', function(req, res) {_x000D_
  res.render('index', {locals: {title: 'Welcome!'}});_x000D_
_x000D_ Here is the content of the index.html file locate inside your 'views' directory:

<!DOCTYPE html>

How can I programmatically determine if my app is running in the iphone simulator?

The previous answers are a little dated. I found that all you need to do is query the TARGET_IPHONE_SIMULATOR macro (no need to include any other header files [assuming you are coding for iOS]).

I attempted TARGET_OS_IPHONE but it returned the same value (1) when running on an actual device and simulator, that's why I recommend using TARGET_IPHONE_SIMULATOR instead.

ArrayList - How to modify a member of an object?

You can do this:

myList.get(3).setEmail("new email");

How to fix 'Microsoft Excel cannot open or save any more documents'

Go to this key on Registry Editor (Run | Regedit) HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders

change key Cache to something like C:\Windows\Temp

My similar problem was solved like this.



Python: Checking if a 'Dictionary' is empty doesn't seem to work

Here are three ways you can check if dict is empty. I prefer using the first way only though. The other two ways are way too wordy.

test_dict = {}

if not test_dict:
    print "Dict is Empty"

if not bool(test_dict):
    print "Dict is Empty"

if len(test_dict) == 0:
    print "Dict is Empty"

HTML-5 date field shows as "mm/dd/yyyy" in Chrome, even when valid date is set

In chrome to set the value you need to do YYYY-MM-DD i guess because this worked :

So to make it work you need to set the date as 2012-10-01

inject bean reference into a Quartz job in Spring?

A solution from Hary works very well. It's simpler, doesn't need so many special factory beans, and support multiple triggers and jobs. Would just add that Quartz job can be made to be generic, with specific jobs implemented as regular Spring beans.

public interface BeanJob {
  void executeBeanJob();

public class GenericJob implements Job {

  public void execute(JobExecutionContext context) throws JobExecutionException {
    JobDataMap dataMap = context.getMergedJobDataMap();


public class RealJob implements BeanJob {
  private SomeService service;

  public RealJob(SomeService service) {
    this.service = service;

  public void executeBeanJob() {
      //do do job with service


What is a "slug" in Django?

It's a descriptive part of the URL that is there to make it more human descriptive, but without necessarily being required by the web server - in What is a "slug" in Django? the slug is 'in-django-what-is-a-slug', but the slug is not used to determine the page served (on this site at least)

Change IPython/Jupyter notebook working directory

import sys

Purpose of "%matplotlib inline"

If you don't know what backend is , you can read this:

Some people use matplotlib interactively from the python shell and have plotting windows pop up when they type commands. Some people run Jupyter notebooks and draw inline plots for quick data analysis. Others embed matplotlib into graphical user interfaces like wxpython or pygtk to build rich applications. Some people use matplotlib in batch scripts to generate postscript images from numerical simulations, and still others run web application servers to dynamically serve up graphs. To support all of these use cases, matplotlib can target different outputs, and each of these capabilities is called a backend; the "frontend" is the user facing code, i.e., the plotting code, whereas the "backend" does all the hard work behind-the-scenes to make the figure.

So when you type %matplotlib inline , it activates the inline backend. As discussed in the previous posts :

With this backend, the output of plotting commands is displayed inline within frontends like the Jupyter notebook, directly below the code cell that produced it. The resulting plots will then also be stored in the notebook document.

Parse DateTime string in JavaScript

Use Date object:

var time = Date.parse('02.02.1999');

Give: 917902800000

Android - SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length

I ran into this problem too when I copied some text from the Internet. My solution is to trim the text/remove formatting before doing any further processing.

how to add key value pair in the JSON object already declared

You can add more key value pair in the same object without replacing old ones in following way:

var obj = {};

obj = {
"1": "aa",
"2": "bb"

obj["3"] = "cc";

Below is the code and jsfiddle link to sample demo that will add more key value pairs to the already existed obj on clicking of button:

var obj = {
    "1": "aa",
    "2": "bb"

var noOfItems = Object.keys(obj).length;

$('#btnAddProperty').on('click', function() {
    obj[noOfItems] = $.trim($('#txtName').val());

Generate fixed length Strings filled with whitespaces

This simple function works for me:

public static String leftPad(String string, int length, String pad) {
      return pad.repeat(length - string.length()) + string;


String s = leftPad(myString, 10, "0");

How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?

This problem has been bothering me for a long time. I noticed that this discussion does not point out the solution on RHEL/Fecora. I am using RHEL and I do not find the configuration files corresponding to AppArmer on Ubuntu, but I solved my problem by making EVERY directory in the directory PATH readable and accessible by mysql. For example, if you create a directory /tmp, the following two commands make SELECT INTO OUTFILE able to output the .sql AND .sql file

chown mysql:mysql /tmp
chmod a+rx /tmp

If you create a directory in your home directory /home/tom, you must do this for both /home and /home/tom.

Implements vs extends: When to use? What's the difference?

Extends : This is used to get attributes of a parent class into base class and may contain already defined methods that can be overridden in the child class.

Implements : This is used to implement an interface (parent class with functions signatures only but not their definitions) by defining it in the child class.

There is one special condition: "What if I want a new Interface to be the child of an existing interface?". In the above condition, the child interface extends the parent interface.

Do on-demand Mac OS X cloud services exist, comparable to Amazon's EC2 on-demand instances?

I just came across this tonight. Can't say if they are legit, how long in business, and whether they'll be around long, but seems interesting. I may give them a try, and will post update if I do.

Per the website, they say they offer hourly pay-as-you-go and weekly/monthly plans, plus there's a free trial.

Per @Iterator, posting update on my findings for this service, moving out from my comments:

I did the trial/evaluation. The trial can be misleading on how the trial works. You may need to signup to see prices but the trial so far, per the trial software download, doesn't appear to be time limited. It's just feature restricted. You signup to get your own account, but you actually use a generic trial login account to do the trial, not your own account. Your own account is used when you actually pay for the service. The trial limits what you can do, install, save, etc. but good enough to give you an idea of how things work. So it doesn't hurt to signup to evaluate and not pay anything.

Persistence of data is offered via saving files to DropBox (pre-installed, you just need login/configure), etc. There is no concept of AMIs, EBS, or some VM image. Their service is actually like a shared website hosting solution, where users timeshare a Mac machine (like timesharing a Unix/Linux server), and I think they limit or periodically purge what you put on the machine, or perhaps rather they don't backup your files, hence use of DropBox to do the backup. One should contact them to clarify this if desired.

They have various pricing options, as you mention the all day pass, monthly plans at $20, and their is a pay as you go plan at $1/hr. I'd probably go with pay as you go based on my usage. The pay as you go is based on prepaid credits (1 credit = 1 hour, billed at 30 credit increments). One caveat is that you need to periodically use the plan at least once every 60 days for the pay as you go plan or else you lose unused credits. So that's like minimum of spending 1 credit /1 hour every 60 days.

One last comment for now, from my evaluation, you'll need high bandwidth to use the service effectively. It's usable over 1.5 Mbps DSL but kind of slow in response. You'd want to use it from a corporate network with Gbps bandwidth for optimal use. Or at least a higher speed cable/DSL broadband connection. On my last test ~3Mbps seemed sufficient on the low bandwidth profile (they have multiple bandwidth connection profiles, low, medium, high, optimized for some bandwidth ranges). I didn't test on the higher ones. Your mileage may vary.

How to Exit a Method without Exiting the Program?

If the function is a void, ending the function will return. Otherwise, you need to do an explicit return someValue. As Mark mentioned, you can also throw an exception. What's the context of your question? Do you have a larger code sample with which to show you some ways to exit the function?

Setting java locale settings

With the user.language, and user.variant properties.


java -Duser.language=th -Duser.variant=TH SomeClass

How to install a PHP IDE plugin for Eclipse directly from the Eclipse environment?

Easy as pie:

Open Eclipse and go to Help-> Software Updates-> Find and Install Select "Search for new features to install" and click "Next" Create a New Remote Site with the following details:

Name: PDT


Get the latest above mentioned URLfrom -

Check the PDT box and click "Next" to start the installation

Hope it helps

Neither user 10102 nor current process has android.permission.READ_PHONE_STATE

On Android >=6.0, We have to request permission runtime.

Step1: add in AndroidManifest.xml file

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

Step2: Request permission.

int permissionCheck = ContextCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE);

if (permissionCheck != PackageManager.PERMISSION_GRANTED) {
    ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_PHONE_STATE}, REQUEST_READ_PHONE_STATE);
} else {

Step3: Handle callback when you request permission.

public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
    switch (requestCode) {
            if ((grantResults.length > 0) && (grantResults[0] == PackageManager.PERMISSION_GRANTED)) {


Edit: Read official guide here Requesting Permissions at Run Time

How to add MVC5 to Visual Studio 2013?

Also, while installing Visual Studio 2013, ensure that you have checked "Web Developer Tools"

Java - How to convert type collection into ArrayList?

Try this code

Convert ArrayList to Collection

  ArrayList<User> usersArrayList = new ArrayList<User>();

  Collection<User> userCollection = new HashSet<User>(usersArrayList);

Convert Collection to ArrayList

  Collection<User> userCollection = new HashSet<User>(usersArrayList);

  List<User> userList = new ArrayList<User>(userCollection );

What are some alternatives to ReSharper?

The main alternative is:

  • CodeRush, by DevExpress. Most consider either this or ReSharper the way to go. You cannot go wrong with either. Both have their fans, both are powerful, and both have talented teams constantly improving them. We have all benefited from the competition between these two. I won't repeat the many good discussions/comparisons about them that can be found on Stack Overflow and elsewhere.

Another alternative worth checking out:

  • JustCode, by Telerik. This is new, still with kinks, but initial reports are positive. An advantage could be licensing with other Telerik products and integration with them. There are bundled licenses available that could make things cheaper / easier to handle.

Create Word Document using PHP in Linux

The Apache project has a library called POI which can be used to generate MS Office files. It is a Java library but the advantage is that it can run on Linux with no trouble. This library has its limitations but it may do the job for you, and it's probably simpler to use than trying to run Word.

Another option would be OpenOffice but I can't exactly recommend it since I've never used it.

Basic example for sharing text or image with UIActivityViewController in Swift

I found this to work flawlessly if you want to share whole screen.

@IBAction func shareButton(_ sender: Any) {

    let bounds = UIScreen.main.bounds
    UIGraphicsBeginImageContextWithOptions(bounds.size, true, 0.0)
    self.view.drawHierarchy(in: bounds, afterScreenUpdates: false)
    let img = UIGraphicsGetImageFromCurrentImageContext()
    let activityViewController = UIActivityViewController(activityItems: [img!], applicationActivities: nil)
    activityViewController.popoverPresentationController?.sourceView = self.view
    self.present(activityViewController, animated: true, completion: nil)

Gradient of n colors ranging from color 1 and color 2

The above answer is useful but in graphs, it is difficult to distinguish between darker gradients of black. One alternative I found is to use gradients of gray colors as follows

palette(gray.colors(10, 0.9, 0.4))

More info on gray scale here.


When I used the code above for different colours like blue and black, the gradients were not that clear. heat.colors() seems more useful.

This document has more detailed information and options. pdf

Creating all possible k combinations of n items in C++

It can also be done using backtracking by maintaining a visited array.

void foo(vector<vector<int> > &s,vector<int> &data,int go,int k,vector<int> &vis,int tot)


    for(int i=go+1;i<=tot;++i)

vector<vector<int> > Solution::combine(int n, int k) {
   vector<int> data;
   vector<int> vis(n+1,0);
   vector<vector<int> > sol;
   for(int i=1;i<=n;++i)
       for(int i=1;i<=n;++i) vis[i]=0;
   return sol;


Best way to run scheduled tasks

This library works like a charm

It allows you to manage Windows scheduled tasks directly through your .NET code.


The best approach I know is to do an update, followed by an insert. The "overhead of a select" is necessary, but it is not a terrible burden since you are searching on the primary key, which is fast.

You should be able to modify the below statements with your table & field names to do what you want.

--first, update any matches
  MY_FIELD1 = (
              SELECT MY_FIELD1
              FROM SOURCE_TABLE ST
 ,MY_FIELD2 = (
              SELECT MY_FIELD2
              FROM SOURCE_TABLE ST
              SOURCE_TABLE ST2

--second, insert any non-matches
 ,NULL AS MY_FIELD2  --insert NULL into this field
                SELECT DT2.PRIMARY_KEY

How to set back button text in Swift

Back-button text is taken from parent view-controller's navigation item title. So whatever you set on previous view-controller's navigation item title, will be shown on current view controller's back button text. You can just put "" as navigation item title in parent view-controller's viewWillAppear method.

self.navigationItem.title = ""

Another way is to put

self.navigationController?.navigationBar.topItem?.title = ""

in current view controller's viewWillAppear method. This one will cause some other problem if navigation stack is too nested.

How do I delete everything in Redis?

You can use FLUSHALL which will delete all keys from your every database. Where as FLUSHDB will delete all keys from our current database.

redirect while passing arguments

I found that none of the answers here applied to my specific use case, so I thought I would share my solution.

I was looking to redirect an unauthentciated user to public version of an app page with any possible URL params. Example:

/app/4903294/my-great-car? to


Here's the solution that worked for me.

return redirect(url_for('app.vehicle', vid=vid, year_make_model=year_make_model, **request.args))

Hope this helps someone!

Import a custom class in Java

If your classes are in the same package, you won't need to import. To call a method from class B in class A, you should use classB.methodName(arg)

How to commit and rollback transaction in sql server?

As per

@@ERROR: Returns the error number for the last Transact-SQL statement executed.

You will have to check after each statement in order to perform the rollback and return.

Commit can be at the end.


How to convert java.sql.timestamp to LocalDate (java8) java.time?

The accepted answer is not ideal, so I decided to add my 2 cents


is a bad solution in general, I'm not even sure why they added this method to the JDK as it makes things really confusing by doing an implicit conversion using the system timezone. Usually when using only java8 date classes the programmer is forced to specify a timezone which is a good thing.

The good solution is


Where zoneId is the timezone you want to use which is typically either ZoneId.systemDefault() if you want to use your system timezone or some hardcoded timezone like ZoneOffset.UTC

The general approach should be

  1. Break free to the new java8 date classes using a class that is directly related, e.g. in our case java.time.Instant is directly related to java.sql.Timestamp, i.e. no timezone conversions are needed between them.
  2. Use the well-designed methods in this java8 class to do the right thing. In our case atZone(zoneId) made it explicit that we are doing a conversion and using a particular timezone for it.

Solr vs. ElasticSearch

If you are already using SOLR, remain stick to it. If you are starting up, go for Elastic search.

Maximum major issues have been fixed in SOLR and it is quite mature.

how to access iFrame parent page using jquery?

in parent window put :

function ifDoneChildFrame(val)

and in iframe src file put :

<script>window.parent.ifDoneChildFrame('Your value here');</script>

What is an idiomatic way of representing enums in Go?

Referring to the answer of jnml, you could prevent new instances of Base type by not exporting the Base type at all (i.e. write it lowercase). If needed, you may make an exportable interface that has a method that returns a base type. This interface could be used in functions from the outside that deal with Bases, i.e.

package a

type base int

const (
    A base = iota

type Baser interface {
    Base() base

// every base must fulfill the Baser interface
func(b base) Base() base {
    return b

func(b base) OtherMethod()  {

package main

import "a"

// func from the outside that handles a.base via a.Baser
// since a.base is not exported, only exported bases that are created within package a may be used, like a.A, a.C, a.T. and a.G
func HandleBasers(b a.Baser) {
    base := b.Base()

// func from the outside that returns a.A or a.C, depending of condition
func AorC(condition bool) a.Baser {
    if condition {
       return a.A
    return a.C

Inside the main package a.Baser is effectively like an enum now. Only inside the a package you may define new instances.

How to access static resources when mapping a global front controller servlet on /*

With regard to Tomcat, a lot depends on the particular version. There was a bug fix which means the servlet-mapping (other than for '/') for the default servlet behaves differently in Tomcat 6.0.29 (and earlier) compared with later versions.

Passing command line arguments in Visual Studio 2010?

  • Right click your project in Solution Explorer and select Properties from the menu
  • Go to Configuration Properties -> Debugging
  • Set the Command Arguments in the property list.

Adding Command Line Arguments

Eliminate extra separators below UITableView

For iOS 7+ using Storyboards

Simply drag a UIView into your UITableView as the footer. Set the footer view's height to 0.

How do I escape only single quotes?

Use the native function htmlspecialchars. It will escape from all special character. If you want to escape from a quote specifically, use with ENT_COMPAT or ENT_QUOTES. Here is the example:

$str = "Jane & 'Tarzan'";
echo htmlspecialchars($str, ENT_COMPAT); // Will only convert double quotes
echo "<br>";

echo htmlspecialchars($str, ENT_QUOTES); // Converts double and single quotes
echo "<br>";

echo htmlspecialchars($str, ENT_NOQUOTES); // Does not convert any quotes

The output would be like this:

Jane &amp; 'Tarzan'<br>
Jane &amp; &#039;Tarzan&#039;<br>
Jane &amp; 'Tarzan'

Read more in PHP htmlspecialchars() Function

Create space at the beginning of a UITextField

//MARK:-  Use this class for different type of Roles

import UIKit

class HelperExtensionViewController: UIViewController {


//MARK:- Extension

extension UIImageView
    func setImageCornerRadius()
        self.layer.cornerRadius = self.frame.size.height/2
        self.clipsToBounds = true

    func setImageCornerRadiusInPoints(getValue:CGFloat)
        self.layer.cornerRadius = getValue
        self.clipsToBounds = true

extension UIButton
    func setButtonCornerRadiusOnly()
        self.layer.cornerRadius = self.frame.size.height/2
        self.clipsToBounds = true

    func setBtnCornerRadiusInPoints(getValue:CGFloat)
        self.layer.cornerRadius = getValue
        self.clipsToBounds = true


extension UITextField
    func setTextFieldCornerRadiusWithBorder()
        self.layer.cornerRadius = self.frame.size.height/2
        self.layer.borderColor = UIColor.darkGray.cgColor
        self.backgroundColor = UIColor.clear
        self.layer.borderWidth = 0.5
        self.clipsToBounds = true

    func setLeftPaddingPoints(_ amount:CGFloat){
        let paddingView = UIView(frame: CGRect(x: 0, y: 0, width: amount, height: self.frame.size.height))
        self.leftView = paddingView
        self.leftViewMode = .always
    func setRightPaddingPoints(_ amount:CGFloat) {
        let paddingView = UIView(frame: CGRect(x: 0, y: 0, width: amount, height: self.frame.size.height))
        self.rightView = paddingView
        self.rightViewMode = .always

extension UIView

    func setCornerRadius()
        self.layer.cornerRadius = self.frame.size.height/2
        self.clipsToBounds = true

    // OUTPUT 1
    func setViewCornerRadiusWithBorder()
        self.layer.cornerRadius = self.frame.size.height/2
        self.layer.borderColor = UIColor.init(red: 95.0/255.0, green: 229.0/255.0, blue: 206.0/255.0, alpha: 1.0).cgColor
        self.backgroundColor = UIColor.clear
        self.layer.borderWidth = 1.0
        self.clipsToBounds = true

    func layoutSubviews(myView:UIView)
        let shadowPath = UIBezierPath(rect: myView.bounds)
        myView.layer.masksToBounds = false
        myView.layer.shadowColor = UIColor.lightGray.cgColor
        myView.layer.shadowOffset = CGSize(width: -1.0, height: 2.0)
        myView.layer.shadowOpacity = 0.5
        myView.layer.shadowPath = shadowPath.cgPath

    func layoutSubviews2(myView:UIView)
        let shadowPath = UIBezierPath(rect: myView.bounds)
        myView.clipsToBounds = true
        myView.layer.masksToBounds = false
        myView.layer.shadowColor =
        myView.layer.shadowOffset = CGSize(width: 0.0, height: 1.0)
        myView.layer.shadowOpacity = 0.2
        myView.layer.shadowPath = shadowPath.cgPath


    func setViewCornerRadiusInPoints(getValue:CGFloat)
        self.layer.cornerRadius = getValue
        self.clipsToBounds = true

    func dropShadow(scale: Bool = true) {
        layer.masksToBounds = false
        layer.shadowColor =
        layer.shadowOpacity = 0.5
        layer.shadowOffset = CGSize(width: -1, height: 1)
        layer.shadowRadius = 1

        layer.shadowPath = UIBezierPath(rect: bounds).cgPath
        layer.shouldRasterize = true
        layer.rasterizationScale = scale ? UIScreen.main.scale : 1

    // OUTPUT 2
    func dropShadow(color: UIColor, opacity: Float = 0.5, offSet: CGSize, radius: CGFloat = 1, scale: Bool = true) {
        layer.masksToBounds = false
        layer.shadowColor = color.cgColor
        layer.shadowOpacity = opacity
        layer.shadowOffset = offSet
        layer.shadowRadius = radius

        layer.shadowPath = UIBezierPath(rect: self.bounds).cgPath
        layer.shouldRasterize = true
        layer.rasterizationScale = scale ? UIScreen.main.scale : 1

    func setGradientBackground(myview:UIView) {
        let colorTop =  UIColor(red: 100.0/255.0, green: 227.0/255.0, blue: 237.0/255.0, alpha: 1.0).cgColor
        let colorBottom = UIColor(red: 141.0/255.0, green: 109.0/255.0, blue: 164.0/255.0, alpha: 1.0).cgColor

        let gradientLayer = CAGradientLayer()
        gradientLayer.colors = [colorTop, colorBottom]
        gradientLayer.locations = [1.0, 1.0]
        gradientLayer.frame = myview.bounds

        myview.layer.insertSublayer(gradientLayer, at:0)

How to restart Jenkins manually?

On Ubuntu or Debian, when installed through apt-get/dpkg:

$ sudo /etc/init.d/jenkins restart
Usage: /etc/init.d/jenkins {start|stop|status|restart|force-reload}

what does the __file__ variable mean/do?

When a module is loaded from a file in Python, __file__ is set to its path. You can then use that with other functions to find the directory that the file is located in.

Taking your examples one at a time:

A = os.path.join(os.path.dirname(__file__), '..')
# A is the parent directory of the directory where program resides.

B = os.path.dirname(os.path.realpath(__file__))
# B is the canonicalised (?) directory where the program resides.

C = os.path.abspath(os.path.dirname(__file__))
# C is the absolute path of the directory where the program resides.

You can see the various values returned from these here:

import os
print(os.path.join(os.path.dirname(__file__), '..'))

and make sure you run it from different locations (such as ./, ~/python/ and so forth) to see what difference that makes.

I just want to address some confusion first. __file__ is not a wildcard it is an attribute. Double underscore attributes and methods are considered to be "special" by convention and serve a special purpose. shows many of the special methods and attributes, if not all of them.

In this case __file__ is an attribute of a module (a module object). In Python a .py file is a module. So import amodule will have an attribute of __file__ which means different things under difference circumstances.

Taken from the docs:

__file__ is the pathname of the file from which the module was loaded, if it was loaded from a file. The __file__ attribute is not present for C modules that are statically linked into the interpreter; for extension modules loaded dynamically from a shared library, it is the pathname of the shared library file.

In your case the module is accessing it's own __file__ attribute in the global namespace.

To see this in action try:

# file:

print globals()
print __file__

And run:


{'__builtins__': <module '__builtin__' (built-in)>, '__name__': '__main__', '__file__':
 '', '__doc__': None, '__package__': None}

How do I set the proxy to be used by the JVM

I am also behind firewall, this worked for me!!

System.setProperty("http.proxyHost", "proxy host addr");
System.setProperty("http.proxyPort", "808");
Authenticator.setDefault(new Authenticator() {
    protected PasswordAuthentication getPasswordAuthentication() {

        return new PasswordAuthentication("domain\\user","password".toCharArray());

URL url = new URL("");
URLConnection con = url.openConnection();

BufferedReader in = new BufferedReader(new InputStreamReader(

// Read it ...
String inputLine;
while ((inputLine = in.readLine()) != null)


How to get the location of the DLL currently executing?

In my case (dealing with my assemblies loaded [as file] into Outlook):


Note the use of CodeBase (not Location) on the Assembly. Others have pointed out alternative methods of locating the assembly.

How do I disable text selection with CSS or JavaScript?

Try this CSS code for cross-browser compatibility.

-webkit-user-select: none;
-khtml-user-select: none;
-moz-user-select: none;
-o-user-select: none;
user-select: none;

How to implement reCaptcha for ASP.NET MVC?

I have added reCaptcha to a project I'm currently working on. I needed it to use the AJAX API as the reCaptcha element was loaded into the page dynamically. I couldn't find any existing controls and the API is simple so I created my own.

I'll post my code here in case anyone finds it useful.

1: Add the script tag to the master page headers

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

2: Add your keys to the web.config

    <add key="ReCaptcha.PrivateKey" value="[key here]" />
    <add key="ReCaptcha.PublicKey" value="[key here]" />

3: Create the Action Attribute and Html Helper extensions

namespace [Your chosen namespace].ReCaptcha
    public enum Theme { Red, White, BlackGlass, Clean }

    public class InvalidKeyException : ApplicationException
        public InvalidKeyException() { }
        public InvalidKeyException(string message) : base(message) { }
        public InvalidKeyException(string message, Exception inner) : base(message, inner) { }

    public class ReCaptchaAttribute : ActionFilterAttribute
        public override void OnActionExecuting(ActionExecutingContext filterContext)
            var userIP = filterContext.RequestContext.HttpContext.Request.UserHostAddress;

            var privateKey = ConfigurationManager.AppSettings.GetString("ReCaptcha.PrivateKey", "");

            if (string.IsNullOrWhiteSpace(privateKey))
                throw new InvalidKeyException("ReCaptcha.PrivateKey missing from appSettings");

            var postData = string.Format("&privatekey={0}&remoteip={1}&challenge={2}&response={3}",

            var postDataAsBytes = Encoding.UTF8.GetBytes(postData);

            // Create web request
            var request = WebRequest.Create("");
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";
            request.ContentLength = postDataAsBytes.Length;
            var dataStream = request.GetRequestStream();
            dataStream.Write(postDataAsBytes, 0, postDataAsBytes.Length);

            // Get the response.
            var response = request.GetResponse();

            using (dataStream = response.GetResponseStream())
                using (var reader = new StreamReader(dataStream))
                    var responseFromServer = reader.ReadToEnd();

                    if (!responseFromServer.StartsWith("true"))
                        ((Controller)filterContext.Controller).ModelState.AddModelError("ReCaptcha", "Captcha words typed incorrectly");

    public static class HtmlHelperExtensions
        public static MvcHtmlString GenerateCaptcha(this HtmlHelper helper, Theme theme, string callBack = null)
            const string htmlInjectString = @"<div id=""recaptcha_div""></div>
<script type=""text/javascript"">
    Recaptcha.create(""{0}"", ""recaptcha_div"", {{ theme: ""{1}"" {2}}});

            var publicKey = ConfigurationManager.AppSettings.GetString("ReCaptcha.PublicKey", "");

            if (string.IsNullOrWhiteSpace(publicKey))
                throw new InvalidKeyException("ReCaptcha.PublicKey missing from appSettings");

            if (!string.IsNullOrWhiteSpace(callBack))
                callBack = string.Concat(", callback: ", callBack);

            var html = string.Format(htmlInjectString, publicKey, theme.ToString().ToLower(), callBack);
            return MvcHtmlString.Create(html);

4: Add the captcha to your view

@using (Html.BeginForm("MyAction", "MyController"))
   @Html.TextBox("EmailAddress", Model.EmailAddress)
   <input type="submit" value="Submit" />

5: Add the attribute to your action

public ActionResult MyAction(MyModel model)
   if (!ModelState.IsValid) // Will have a Model Error "ReCaptcha" if the user input is incorrect
      return Json(new { capthcaInvalid = true });

   ... other stuff ...

6: Note you will need to reload the captcha after each post even if it was valid and another part of the form was invalid. Use Recaptcha.reload();

How to put a UserControl into Visual Studio toolBox

Recompiling did the trick for me!

java.lang.IllegalStateException: Fragment not attached to Activity

This error can happen if you are instantiating a fragment that somehow can't be instantiated:

Fragment myFragment = MyFragment.NewInstance();

public classs MyFragment extends Fragment {
  public void onCreate() {
   // Some error here, or anywhere inside the class is preventing it from being instantiated

In my case, i have met this when i tried to use:

private String loading = getString(R.string.loading);

How to define Typescript Map of key value pair. where key is a number and value is an array of objects

The most simple way is to use Record type Record<number, productDetails >

interface productDetails {
   productId : number , 
   price : number , 
   discount : number

const myVar : Record<number, productDetails> = {
   1: {
       productId : number , 
       price : number , 
       discount : number

Android-Studio upgraded from 0.1.9 to 0.2.0 causing gradle build errors now

For people who have this problem today(to example to switch from 2.8.0 to 2.10.0), move to file and set distributionUrl with the value you need. distributionUrl=https\://

I changed 2.8.0 to 2.10.0 and dont forget to Sync after

Simplest way to do grouped barplot

There are several ways to do plots in R; lattice is one of them, and always a reasonable solution, +1 to @agstudy. If you want to do this in base graphics, you could try the following:

Reasonstats <- read.table(text="Category         Reason  Species
                                 Decline        Genuine       24
                                Improved        Genuine       16
                                Improved  Misclassified       85
                                 Decline  Misclassified       41
                                 Decline      Taxonomic        2
                                Improved      Taxonomic        7
                                 Decline        Unclear       41
                                Improved        Unclear      117", header=T)

ReasonstatsDec <- Reasonstats[which(Reasonstats$Category=="Decline"),]
ReasonstatsImp <- Reasonstats[which(Reasonstats$Category=="Improved"),]
Reasonstats3   <- cbind(ReasonstatsImp[,3], ReasonstatsDec[,3])
colnames(Reasonstats3) <- c("Improved", "Decline")
rownames(Reasonstats3) <- ReasonstatsImp$Reason

  barplot(t(Reasonstats3), beside=TRUE, ylab="number of species", 
          cex.names=0.8, las=2, ylim=c(0,120), col=c("darkblue","red"))

enter image description here

Here's what I did: I created a matrix with two columns (because your data were in columns) where the columns were the species counts for Decline and for Improved. Then I made those categories the column names. I also made the Reasons the row names. The barplot() function can operate over this matrix, but wants the data in rows rather than columns, so I fed it a transposed version of the matrix. Lastly, I deleted some of your arguments to your barplot() function call that were no longer needed. In other words, the problem was that your data weren't set up the way barplot() wants for your intended output.

Append to the end of a file in C

Open with append:

pFile2 = fopen("myfile2.txt", "a");

then just write to pFile2, no need to fseek().

How can I install Visual Studio Code extensions offline?

UPDATE 2017-12-13

You can now download the extension directly from the marketplace.

Enter image description here

As of Visual Studio Code 1.7.1 dragging or opening the extension does not work any more. In order to install it manually you need to:

  • open the extensions sidebar
  • click on the ellipsis in the right upper corner
  • choose Install from VSIX

Install from VSIX...

Old Method

According to the documentation it is possible to download an extension directly:

An extension's direct download URL is in the form:

https://${publisher}${publisher}/extension/${extension name}/${version}/assetbyname/Microsoft.VisualStudio.Services.VSIXPackage

This means that in order to download the extension you need to know

  • the publisher name
  • the version
  • the extension name

You can find all this information in the URL.


Here's an example for downloading an installing the C# v1.3.0 extension:

Publisher, Extension and Version

You can find the publisher and the extension names on the extension's homepage inside its URL:

Here the publisher is ms-vscode and the extension name is csharp.

The version can be found on the right side in the More Info area.

To download it you need to create a link from the template above:

All packages will have the same name Microsoft.VisualStudio.Services.VSIXPackage, so you'll need to rename it after downloading if you want to know what package it was later.


In order to install the extension

  • Rename the file and give it the *.vsix extension
  • Open Visual Studio Code, go to menu FileOpen File... or Ctrl + O and select the .vsix file
  • If everything went fine, you should see this message at the top of the window:

Extension was successfully installed. Restart to enable it.

Difference between string and text in rails?

String translates to "Varchar" in your database, while text translates to "text". A varchar can contain far less items, a text can be of (almost) any length.

For an in-depth analysis with good references check

Edit: Some database engines can load varchar in one go, but store text (and blob) outside of the table. A SELECT name, amount FROM products could, be a lot slower when using text for name than when you use varchar. And since Rails, by default loads records with SELECT * FROM... your text-columns will be loaded. This will probably never be a real problem in your or my app, though (Premature optimization is ...). But knowing that text is not always "free" is good to know.

jQuery same click event for multiple elements

I have a link to an object containig many input fields, which requires to be handled by the same event. So I simply use find() to get all the inside objects, that need to have the event

var form = $('<form></form>');
// ... apending several input fields

form.find('input').on('change', onInputChange);

In case your objects are one level down the link children() instead find() method can be used.

Where can I download Spring Framework jars without using Maven?

Please edit to keep this list of mirrors current

I found this maven repo where you could download from directly a zip file containing all the jars you need.

Alternate solution: Maven

The solution I prefer is using Maven, it is easy and you don't have to download each jar alone. You can do it with the following steps:

  1. Create an empty folder anywhere with any name you prefer, for example spring-source

  2. Create a new file named pom.xml

  3. Copy the xml below into this file

  4. Open the spring-source folder in your console

  5. Run mvn install

  6. After download finished, you'll find spring jars in /spring-source/target/dependencies

    <project xmlns="" xmlns:xsi="" xsi:schemaLocation="">

Also, if you need to download any other spring project, just copy the dependency configuration from its corresponding web page.

For example, if you want to download Spring Web Flow jars, go to its web page, and add its dependency configuration to the pom.xml dependencies, then run mvn install again.


Set selected item in Android BottomNavigationView


There are plenty of (mostly repeated or outdated) answers here but none of them handles a very common need: dynamically passing different arguments to the Fragment loaded into a tab.

You can't dynamically pass different arguments to the loaded Fragment by using setSelectedItemId(, which ends up calling the static OnNavigationItemSelectedListener. To overcome this limitation I've ended up doing this in my MainActivity that contains the tabs:

fun loadArticleTab(articleId: String) { = true // use setChecked() in Java
        .replace(, ArticleFragment.newInstance(articleId))

The ArticleFragment.newInstance() method is implemented as usual:

private const val ARG_ARTICLE_ID = "ARG_ARTICLE_ID"

class ArticleFragment : Fragment() {

    companion object {
         * @return An [ArticleFragment] that shows the article with the given ID.
        fun newInstance(articleId: String): ArticleFragment {
            val args = Bundle()
            args.putString(ARG_ARTICLE_ID, day)
            val fragment = ArticleFragment()
            fragment.arguments = args
            return fragment


DateTimePicker time picker in 24 hour but displaying in 12hr?

The catch is that hh is for format 12 hours and HH is for 24 hours.

24 hour format

$(function () {
        format: 'HH:mm',           

12 hour format

$(function () {
        format: 'hh:mm',           

Get a json via Http Request in NodeJS

Just tell request that you are using json:true and forget about header and parse

var options = {
    hostname: '',
    port: app.get('port'),
    path: '/users',
    method: 'GET',
request(options, function(error, response, body){
    if(error) console.log(error);
    else console.log(body);

and the same for post

var options = {
    hostname: '',
    port: app.get('port'),
    path: '/users',
    method: 'POST',
    json: {"name":"John", "lastname":"Doe"}
request(options, function(error, response, body){
    if(error) console.log(error);
    else console.log(body);

What is the attribute property="og:title" inside meta tag?

Probably part of Open Graph Protocol for Facebook.

Edit: guess not only Facebook - that's only one example of using it.

Check if a temporary table exists and delete if it exists before creating a temporary table

When you change a column in a temp table, you must drop the table before running the query again. (Yes, it is annoying. Just what you have to do.)

I have always assumed this is because the "invalid column" check is done by parser before the query is run, so it is based on the columns in the table before it is dropped..... and that is what pnbs also said.

Is it possible to use a batch file to establish a telnet session, send a command and have the output written to a file?

The microsoft telnet.exe is not scriptable without using another script (which needs keyboard focus), as shown in another answer to this question, but there is a free

Telnet Scripting Tool v.1.0 by Albert Yale

that you can google for and which is both scriptable and loggable and can be launched from a batch file without needing keyboard focus.

The problem with telnet.exe and a second script when keyboard focus is being used is that if someone is using the computer at the time the script runs, then it is highly likely that the script will fail due to mouse clicks and keyboard use at that moment in time.

Call to undefined function App\Http\Controllers\ [ function name ]

If they are in the same controller class, it would be:

foreach ( $characters as $character) {
    $num += $this->getFactorial($index) * $index;
    $index ++;

Otherwise you need to create a new instance of the class, and call the method, ie:

$controller = new MyController();
foreach ( $characters as $character) {
    $num += $controller->getFactorial($index) * $index;
    $index ++;

How do I run Python script using arguments in windows command line

To execute your program from the command line, you have to call the python interpreter, like this :

C:\Python27>python 1 1

If you code resides in another directory, you will have to set the python binary path in your PATH environment variable, to be able to run it, too. You can find detailed instructions here.

Inline CSS styles in React: how to implement a:hover?

This can be a nice hack for having inline style inside a react component (and also using :hover CSS function):


  {`.galleryThumbnail.selected:hover{outline:2px solid #00c6af}`}