Programs & Examples On #Lzo

LZO is a (text) compression algorithm from the Lempel-Ziv family, which favours speed against compression ratio.

Uncaught (in promise): Error: StaticInjectorError(AppModule)[options]

Here is what worked for me (Angular 7):

First import HttpClientModule in your app.module.ts if you didn't:

import { HttpClientModule } from '@angular/common/http';
imports: [

Then change your service

export class FooService {


    providedIn: 'root'
export class FooService {

Hope it helps.



Determines which injectors will provide the injectable, by either associating it with an @NgModule or other InjectorType, or by specifying that this injectable should be provided in one of the following injectors:

'root' : The application-level injector in most apps.

'platform' : A special singleton platform injector shared by all applications on the page.

'any' : Provides a unique instance in every module (including lazy modules) that injects the token.

Be careful platform is available only since Angular 9 (

Read more about Injectable here:

Pods stuck in Terminating status

The original question is "What could be the reason for this issue?" and the answer is discussed at & & see

Its caused by docker mount leaking into some other namespace.

You can logon to pod host to investigate.

minikube ssh
docker container ps | grep <id>
docker container stop <id> 

How do I resolve this "ORA-01109: database not open" error?

I was facing some problem from SQL PLUS Command Promt.

So I resolve this issue from windows CMD ,I follow such steps--->

1: open CMD (Windows)

2: type show pdbs;

   now u have to unmount the data base which is mounted

3: type alter pluggable database database_Name open;

4: type show pdbs;(for cross check)

It works for me

get all keys set in memcached

The easiest way is to use python-memcached-stats package,

The keys() method should get you going.

Example -

from memcached_stats import MemcachedStats
mem = MemcachedStats()

 ... ]

Python base64 data decode

Note Slipstream's response, that base64.b64encode and base64.b64decode need bytes-like object, not string.

>>> import base64
>>> a = '{"name": "John", "age": 42}'
>>> base64.b64encode(a)
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/usr/lib/python3.6/", line 58, in b64encode
    encoded = binascii.b2a_base64(s, newline=False)
TypeError: a bytes-like object is required, not 'str'

How to get CPU temperature?

I'm pretty sure it's manufacturer dependent, since they will be accessed through an I/O port. If you have a specific board you're trying to work with, try looking through the manuals and/or contacting the manufacturer.

If you want to do this for a lot of different boards, I'd recommend contacting someone at something like SiSoftware or be prepared to read a LOT of motherboard manuals.

As another note, not all boards have temperature monitors.

You also might run into problems getting privileged access from the kernel.

How to programmatically set the layout_align_parent_right attribute of a Button in Relative Layout?

For adding a RelativeLayout attribute whose value is true or false use 0 for false and RelativeLayout.TRUE for true:

RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) button.getLayoutParams()
params.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, RelativeLayout.TRUE)

It doesn't matter whether or not the attribute was already added, you still use addRule(verb, subject) to enable/disable it. However, post-API 17 you can use removeRule(verb) which is just a shortcut for addRule(verb, 0).

Git push error pre-receive hook declined

GitLab by default marks master branch as protected (See part Protecting your code in why). If so in your case, then this can help:

Open your project > Settings > Repository and go to "Protected branches", find "master" branch into the list and click "Unprotect" and try again.


For version 8.11 and above how-to here:

How to float a div over Google Maps?

absolute positioning is evil... this solution doesn't take into account window size. If you resize the browser window, your div will be out of place!

Swift: Display HTML data in a label or textView

For Swift 5:

extension String {
    var htmlToAttributedString: NSAttributedString? {
        guard let data = data(using: .utf8) else { return nil }
        do {
            return try NSAttributedString(data: data, options: [.documentType: NSAttributedString.DocumentType.html, .characterEncoding:String.Encoding.utf8.rawValue], documentAttributes: nil)
        } catch {
            return nil
    var htmlToString: String {
        return htmlToAttributedString?.string ?? ""

Then, whenever you want to put HTML text in a UITextView use:

textView.attributedText = htmlText.htmlToAttributedString

Prepend line to beginning of a file

If the file is the too big to use as a list, and you simply want to reverse the file, you can initially write the file in reversed order and then read one line at the time from the file's end (and write it to another file) with file-read-backwards module

How can I change text color via keyboard shortcut in MS word 2010

You could use a macro, but it’s simpler to use styles. Define a character style that has the desired text color and assign a shortcut key to it, say Alt+R. In order to be able to switch color using just the keyboard, define another character style, say “normal”, that has no special feature—just for use to get normal text after switching to your colored style, and assign another shortcut to it, say Alt+N. Then you would just type text, press Alt+R to switch to colored text, type that text, press Alt+N to resume normal text color, etc.

Creating a generic method in C#

You can use sort of Maybe monad (though I'd prefer Jay's answer)

public class Maybe<T>
    private readonly T _value;

    public Maybe(T value)
        _value = value;
        IsNothing = false;

    public Maybe()
        IsNothing = true;

    public bool IsNothing { get; private set; }

    public T Value
            if (IsNothing)
                throw new InvalidOperationException("Value doesn't exist");
            return _value;

    public override bool Equals(object other)
        if (IsNothing)
            return (other == null);
        if (other == null)
            return false;
        return _value.Equals(other);

    public override int GetHashCode()
        if (IsNothing)
            return 0;
        return _value.GetHashCode();

    public override string ToString()
        if (IsNothing)
            return "";
        return _value.ToString();

    public static implicit operator Maybe<T>(T value)
        return new Maybe<T>(value);

    public static explicit operator T(Maybe<T> value)
        return value.Value;

Your method would look like:

    public static Maybe<T> GetQueryString<T>(string key) where T : IConvertible
        if (String.IsNullOrEmpty(HttpContext.Current.Request.QueryString[key]) == false)
            string value = HttpContext.Current.Request.QueryString[key];

                return (T)Convert.ChangeType(value, typeof(T));
                //Could not convert.  Pass back default value...
                return new Maybe<T>();

        return new Maybe<T>();

How to: Add/Remove Class on mouseOver/mouseOut - JQuery .hover?

You could just use: {in and out function callback}

$(".result").hover(function () {

For your example, better will be to use CSS pseudo class :hover: {no js/jquery needed}

.result {
    height: 72px;
    width: 100%;
    border: 1px solid #000;
  .result:hover {
    background-color: #000;

Pass in an enum as a method parameter

Change the signature of the CreateFile method to expect a SupportedPermissions value instead of plain Enum.

public string CreateFile(string id, string name, string description, SupportedPermissions supportedPermissions)
    file = new File
        Name = name,
        Id = id,
        Description = description,
        SupportedPermissions = supportedPermissions

    return file.Id;

Then when you call your method you pass the SupportedPermissions value to your method

  var basicFile = CreateFile(myId, myName, myDescription, SupportedPermissions.basic);

How to use regex with find command?

Try to use single quotes (') to avoid shell escaping of your string. Remember that the expression needs to match the whole path, i.e. needs to look like:

 find . -regex '\./[a-f0-9-]*.jpg'

Apart from that, it seems that my find (GNU 4.4.2) only knows basic regular expressions, especially not the {36} syntax. I think you'll have to make do without it.

Create local maven repository

Yes you can! For a simple repository that only publish/retrieve artifacts, you can use nginx.

  1. Make sure nginx has http dav module enabled, it should, but nonetheless verify it.

  2. Configure nginx http dav module:

    In Windows: d:\servers\nginx\nginx.conf

    location / {
        # maven repository
        dav_methods  PUT DELETE MKCOL COPY MOVE;
        create_full_put_path  on;
        dav_access  user:rw group:rw all:r;

    In Linux (Ubuntu): /etc/nginx/sites-available/default

    location / {
            # First attempt to serve request as file, then
            # as directory, then fall back to displaying a 404.
            # try_files $uri $uri/ =404;  # IMPORTANT comment this
            dav_methods  PUT DELETE MKCOL COPY MOVE;
            create_full_put_path  on;
            dav_access  user:rw group:rw all:r;

    Don't forget to give permissions to the directory where the repo will be located:

    sudo chmod +777 /var/www/html/repository

  3. In your project's pom.xml add the respective configuration:

    Retrieve artifacts:


    Publish artifacts:

  4. To publish artifacts use mvn deploy. To retrieve artifacts, maven will do it automatically.

And there you have it a simple maven repo.

How to quickly form groups (quartiles, deciles, etc) by ordering column(s) in a data frame

The method I use is one of these or Hmisc::cut2(value, g=4):

temp$quartile <- with(temp, cut(value, 
                                breaks=quantile(value, probs=seq(0,1, by=0.25), na.rm=TRUE), 

An alternate might be:

temp$quartile <- with(temp, factor(
                            findInterval( val, c(-Inf,
                               quantile(val, probs=c(0.25, .5, .75)), Inf) , na.rm=TRUE), 

The first one has the side-effect of labeling the quartiles with the values, which I consider a "good thing", but if it were not "good for you", or the valid problems raised in the comments were a concern you could go with version 2. You can use labels= in cut, or you could add this line to your code:

temp$quartile <- factor(temp$quartile, levels=c("1","2","3","4") )

Or even quicker but slightly more obscure in how it works, although it is no longer a factor, but rather a numeric vector:

temp$quartile <- as.numeric(temp$quartile)

Remove all subviews?

Use the Following code to remove all subviews.

for (UIView *view in [self.view subviews]) 
 [view removeFromSuperview];

JavaScript: Get image dimensions

Make a new Image

var img = new Image();

Set the src

img.src = your_src

Get the width and the height


Capture close event on Bootstrap Modal

Alternative way to check would be:

if (!$('#myModal').is(':visible')) {
    // if modal is not shown/visible then do something

can you add HTTPS functionality to a python flask web server?

For a quick n' dirty self-signed cert, you can also use flask run --cert adhoc or set the FLASK_RUN_CERT env var.

$ export FLASK_APP=""
$ export FLASK_ENV=development
$ export FLASK_RUN_CERT=adhoc

$ flask run
 * Serving Flask app "" (lazy loading)
 * Environment: development
 * Debug mode: on
 * Running on (Press CTRL+C to quit)
 * Restarting with stat
 * Debugger is active!
 * Debugger PIN: 329-665-000

The adhoc option isn't well documented (for good reason, never do this in production), but it's mentioned in the source code.

There's a thorough explanation of this by Miguel Grinberg at Running Your Flask Application Over HTTPS.

How to remove a directory from git repository?

To add new directory:


But now Git is not aware by this new directory, because Git keep tracks of file not directories DIRECTORY

git status

Git won't be aware with the change we've made, so we add hidden .keep file to make Git aware by this new change.

touch /YOUR-directory/.keep

Now, if you hit git status Git will be aware with the changes.

And If you want to delete the directory, you should use this command.


And If you checked by using git status, you will see the directory has been removed.

Select current element in jQuery

You will find the siblings() and parent() methods useful here.

// assuming A1 is clicked
$('div a').click(function(e) {
    $(this); // A1
    $(this).parent(); // the div containing A1
    $(this).siblings(); // A2 and A3

Combining those methods with andSelf() will let you manipulate any combination of those elements you want.

Edit: The comment left by Mark regarding event delegation on Shog9's answer is a very good one. The easiest way to accomplish this in jQuery would be by using the live() method.

// assuming A1 is clicked
$('div a').live('click', function(e) {
    $(this); // A1
    $(this).parent(); // the div containing A1
    $(this).siblings(); // A2 and A3

I think it actually binds the event to the root element, but the effect is that same. Not only is it more flexible, it also improves performance in a lot of cases. Just be sure to read the documentation to avoid any gotchas.

What does "subject" mean in certificate?

My typical expectation is than when "subject" is used a context like this, it means the target of the certificate. If you think of a certificate as a cryptographically secured description of a thing (person, device, communication channel, etc), then the subject is the stuff related to that thing.

It's not the thing itself. For example, no one would say "the subject takes his SmartCard and authenticates his PIN". That would be the "user".

But it usually relates to the various data items related to that that thing. For example:

  • Subject DN = Subject Distinguished Name = the unique identifier for what this thing is. Includes information about the thing being certified, including common name, organization, organization unit, country codes, etc.
  • Subject Key = part (or all) of the certificate's private/public key pair. If it's coming from the certificate, it's the public key. If it's coming from a key store in a secure location, it's probably the private key. Either part of the key is the cryptographic data used by the thing that received the certificate.
  • Subject certificate - the end point for the transaction - this is the thing requesting some secure capability - like integrity checking, authentication, privacy, etc.

Usually, it's used to distinguish between the other players in the PKI world. Namely the "issuer" and the "root". The issuer is the CA that issued the cert (to the subject), and the root is the CA that is end point of all the trust in the heirarchy. The typical relationship is root--->issuer--->subject.

"The transaction log for database is full due to 'LOG_BACKUP'" in a shared host

Call your hosting company and either have them set up regular log backups or set the recovery model to simple. I'm sure you know what informs the choice, but I'll be explicit anyway. Set the recovery model to full if you need the ability to restore to an arbitrary point in time. Either way the database is misconfigured as is.

Append an empty row in dataframe using pandas

Assuming df is your dataframe,

df_prime = pd.concat([df, pd.DataFrame([[np.nan] * df.shape[1]], columns=df.columns)], ignore_index=True)

where df_prime equals df with an additional last row of NaN's.

Note that pd.concat is slow so if you need this functionality in a loop, it's best to avoid using it. In that case, assuming your index is incremental, you can use

df.loc[df.iloc[-1].name + 1,:] = np.nan

Are 'Arrow Functions' and 'Functions' equivalent / interchangeable?

tl;dr: No! Arrow functions and function declarations / expressions are not equivalent and cannot be replaced blindly.
If the function you want to replace does not use this, arguments and is not called with new, then yes.

As so often: it depends. Arrow functions have different behavior than function declarations / expressions, so let's have a look at the differences first:

1. Lexical this and arguments

Arrow functions don't have their own this or arguments binding. Instead, those identifiers are resolved in the lexical scope like any other variable. That means that inside an arrow function, this and arguments refer to the values of this and arguments in the environment the arrow function is defined in (i.e. "outside" the arrow function):

// Example using a function expression
function createObject() {
  console.log('Inside `createObject`:',;
  return {
    foo: 42,
    bar: function() {
      console.log('Inside `bar`:',;
}{foo: 21}).bar(); // override `this` inside createObject

// Example using a arrow function
function createObject() {
  console.log('Inside `createObject`:',;
  return {
    foo: 42,
    bar: () => console.log('Inside `bar`:',,
}{foo: 21}).bar(); // override `this` inside createObject

In the function expression case, this refers to the object that was created inside the createObject. In the arrow function case, this refers to this of createObject itself.

This makes arrow functions useful if you need to access the this of the current environment:

// currently common pattern
var that = this;
getData(function(data) { = data;

// better alternative with arrow functions
getData(data => { = data;

Note that this also means that is not possible to set an arrow function's this with .bind or .call.

If you are not very familiar with this, consider reading

2. Arrow functions cannot be called with new

ES2015 distinguishes between functions that are callable and functions that are constructable. If a function is constructable, it can be called with new, i.e. new User(). If a function is callable, it can be called without new (i.e. normal function call).

Functions created through function declarations / expressions are both constructable and callable.
Arrow functions (and methods) are only callable. class constructors are only constructable.

If you are trying to call a non-callable function or to construct a non-constructable function, you will get a runtime error.

Knowing this, we can state the following.


  • Functions that don't use this or arguments.
  • Functions that are used with .bind(this)

Not replaceable:

  • Constructor functions
  • Function / methods added to a prototype (because they usually use this)
  • Variadic functions (if they use arguments (see below))

Lets have a closer look at this using your examples:

Constructor function

This won't work because arrow functions cannot be called with new. Keep using a function declaration / expression or use class.

Prototype methods

Most likely not, because prototype methods usually use this to access the instance. If they don't use this, then you can replace it. However, if you primarily care for concise syntax, use class with its concise method syntax:

class User {
  constructor(name) { = name;
  getName() {

Object methods

Similarly for methods in an object literal. If the method wants to reference the object itself via this, keep using function expressions, or use the new method syntax:

const obj = {
  getName() {
    // ...


It depends. You should definitely replace it if you are aliasing the outer this or are using .bind(this):

// old
setTimeout(function() {
  // ...
}.bind(this), 500);

// new
setTimeout(() => {
  // ...
}, 500);

But: If the code which calls the callback explicitly sets this to a specific value, as is often the case with event handlers, especially with jQuery, and the callback uses this (or arguments), you cannot use an arrow function!

Variadic functions

Since arrow functions don't have their own arguments, you cannot simply replace them with an arrow function. However, ES2015 introduces an alternative to using arguments: the rest parameter.

// old
function sum() {
  let args = [];
  // ...

// new
const sum = (...args) => {
  // ...

Related question:

Further resources:

Passing arguments forward to another javascript function

The explanation that none of the other answers supplies is that the original arguments are still available, but not in the original position in the arguments object.

The arguments object contains one element for each actual parameter provided to the function. When you call a you supply three arguments: the numbers 1, 2, and, 3. So, arguments contains [1, 2, 3].

function a(args){
    console.log(arguments) // [1, 2, 3]

When you call b, however, you pass exactly one argument: a's arguments object. So arguments contains [[1, 2, 3]] (i.e. one element, which is a's arguments object, which has properties containing the original arguments to a).

function b(args){
    // arguments are lost?
    console.log(arguments) // [[1, 2, 3]]


As @Nick demonstrated, you can use apply to provide a set arguments object in the call.

The following achieves the same result:

function a(args){
    b(arguments[0], arguments[1], arguments[2]); // three arguments

But apply is the correct solution in the general case.

How to do a scatter plot with empty circles in Python?

Here's another way: this adds a circle to the current axes, plot or image or whatever :

from matplotlib.patches import Circle  # $matplotlib/

def circle( xy, radius, color="lightsteelblue", facecolor="none", alpha=1, ax=None ):
    """ add a circle to ax= or current axes
        # from .../pylab_examples/
    e = Circle( xy=xy, radius=radius )
    if ax is None:
        ax = pl.gca()  # ax = subplot( 1,1,1 )
    e.set_edgecolor( color )
    e.set_facecolor( facecolor )  # "none" not None
    e.set_alpha( alpha )

alt text

(The circles in the picture get squashed to ellipses because imshow aspect="auto" ).

Removing duplicate objects with Underscore for Javascript

Implementation of Shiplu's answer.

var foo = [ { "a" : "1" }, { "b" : "2" }, { "a" : "1" } ];

var x = _.uniq( _.collect( foo, function( x ){
    return JSON.stringify( x );

console.log( x ); // returns [ { "a" : "1" }, { "b" : "2" } ]

Angular js init ng-model from default values

As others pointed out, it is not good practice to initialize data on views. Initializing data on Controllers, however, is recommended. (see

So you can write

<input name="card[description]" ng-model="card.description">


$scope.card = { description: 'Visa-4242' };

$http.get('/getCardInfo.php', function(data) {
   $scope.card = data;

This way the views do not contain data, and the controller initializes the value while the real values are being loaded.

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

In MCEdit toggle Shift+F3 (ie F13) or F9->Edit ->Mark columns.

P.S. In this case, MCEdit is an editor written for the Midnight Commander.

How do I make a composite key with SQL Server Management Studio?

In design mode (right click table select modify) highlight both columns right click and choose set primary key

How do I change UIView Size?

You can do this in Interface Builder:

1) Control-drag from a frame view (e.g. questionFrame) to main View, in the pop-up select "Equal heights".

2)Then go to size inspector of the frame, click edit "Equal height to Superview" constraint, set the multiplier to 0.7 and hit return.

You'll see that constraint has changed from "Equal height to..." to "Proportional height to...".

PHP Warning: include_once() Failed opening '' for inclusion (include_path='.;C:\xampp\php\PEAR')

This should work if current file is located in same directory where initcontrols is:

$base_dir = realpath(dirname(__FILE__)  . $ds . '..') . $ds;
$file = "{$base_dir}initcontrols{$ds}header_myworks.php"; 
echo $plHeader;?>   

What is Persistence Context?

Both the org.hibernate.Session API and javax.persistence.EntityManager API represent a context for dealing with persistent data.

This concept is called a persistence context. Persistent data has a state in relation to both a persistence context and the underlying database.

How to use a decimal range() step value?

You can use this function:

def frange(start,end,step):
    return map(lambda x: x*step, range(int(start*1./step),int(end*1./step)))

Can you issue pull requests from the command line on GitHub?

I've created a tool recently that does exactly what you want:

It automates everything in a single command, forking the repo, pushing the PR etc. It also supports updating the PR if you need to edit/fix it!

Android: keeping a background service alive (preventing process death)

When you bind your Service to Activity with BIND_AUTO_CREATE your service is being killed just after your Activity is Destroyed and unbound. It does not depend on how you've implemented your Services unBind method it will be still killed.

The other way is to start your Service with startService method from your Activity. This way even if your Activity is destroyed your service won't be destroyed or even paused but you have to pause/destroy it by yourself with stopSelf/stopService when appropriate.

How to Decode Json object in laravel and apply foreach loop on that in laravel

your string is NOT a valid json to start with.

a valid json will be,

    "area": [
            "area": "kothrud"
            "area": "katraj"

if you do a json_decode, it will yield,

stdClass Object
    [area] => Array
            [0] => stdClass Object
                    [area] => kothrud

            [1] => stdClass Object
                    [area] => katraj



Update: to use

$string = '

    "area": [
            "area": "kothrud"
            "area": "katraj"

            $area = json_decode($string, true);

            foreach($area['area'] as $i => $v)
                echo $v['area'].'<br/>';



Update #2:

for that true:

When TRUE, returned objects will be converted into associative arrays. for more information, click here

How to resize images proportionally / keeping the aspect ratio?

If I understand the question correctly, you don't even need jQuery for this. Shrinking the image proportionally on the client can be done with CSS alone: just set its max-width and max-height to 100%.

<div style="height: 100px">
<img src=""
    style="max-height: 100%; max-width: 100%">

Here's the fiddle:

Programmatically set image to UIImageView with Xcode 6.1/Swift

This code is in the wrong place:

var image : UIImage = UIImage(named:"afternoon")!
bgImage = UIImageView(image: image)
bgImage.frame = CGRect(x: 0, y: 0, width: 100, height: 200)

You must place it inside a function. I recommend moving it inside the viewDidLoad function.

In general, the only code you can add within the class that's not inside of a function are variable declarations like:

@IBOutlet weak var bgImage: UIImageView!

How to convert an IPv4 address into a integer in C#?

My question was closed, I have no idea why . The accepted answer here is not the same as what I need.

This gives me the correct integer value for an IP..

public double IPAddressToNumber(string IPaddress)
    int i;
    string [] arrDec;
    double num = 0;
    if (IPaddress == "")
        return 0;
        arrDec = IPaddress.Split('.');
        for(i = arrDec.Length - 1; i >= 0 ; i = i -1)
                num += ((int.Parse(arrDec[i])%256) * Math.Pow(256 ,(3 - i )));
        return num;

How do I do an OR filter in a Django query?

It is worth to note that it's possible to add Q expressions.

For example:

from django.db.models import Q

query = Q(first_name='mark')
query.add(Q(email='[email protected]'), Q.OR)
query.add(Q(last_name='doe'), Q.AND)

queryset = User.objects.filter(query)

This ends up with a query like :

(first_name = 'mark' or email = '[email protected]') and last_name = 'doe'

This way there is no need to deal with or operators, reduce's etc.

Saving results with headers in Sql Server Management Studio

I also face the same issue. When I used right click in the query window and select Query Options. But header rows does not show up in output CSV file.

Then I logoff the server, login again and run the script. Then it worked.

Get last 5 characters in a string

Error check:

result = str.Substring(Math.Max(0, str.Length - 5))

Difference between signed / unsigned char

I slightly disagree with the above. The unsigned char simply means: Use the most significant bit instead of treating it as a bit flag for +/- sign when performing arithmetic operations.

It makes significance if you use char as a number for instance:

typedef char BYTE1;
typedef unsigned char BYTE2;

BYTE1 a;
BYTE2 b;

For variable a, only 7 bits are available and its range is (-127 to 127) = (+/-)2^7 -1. For variable b all 8 bits are available and the range is 0 to 255 (2^8 -1).

If you use char as character, "unsigned" is completely ignored by the compiler just as comments are removed from your program.

Remove non-numeric characters (except periods and commas) from a string

If letters are always in the beginning or at the end, you can simply just use regex needed

$string = trim($string, "a..zA..Z"); // this also take care of lowercase

"AR3,373.31" --> "3,373.31"
"12.322,11T" --> "12.322,11"
"12.322,11"  --> "12.322,11"

Generate signed apk android studio

you can add this to your build gradel

android {
    defaultConfig { ... }
    signingConfigs {
        release {
            storeFile file("my.keystore")
            storePassword "password"
            keyAlias "MyReleaseKey"
            keyPassword "password"
    buildTypes {
        release {
            signingConfig signingConfigs.release

if you then need a keyHash do like this via android stdio terminal on project root folder

keytool -exportcert -alias my.keystore -keystore app/my.keystore.jks | openssl sha1 -binary | openssl base64

Extract names of objects from list

You can just use:

> names(LIST)
[1] "A" "B"

Obviously the names of the first element is just

> names(LIST)[1]
[1] "A"

Retrieving a Foreign Key value with django-rest-framework serializers

Another thing you can do is to:

  • create a property in your Item model that returns the category name and
  • expose it as a ReadOnlyField.

Your model would look like this.

class Item(models.Model):
    name = models.CharField(max_length=100)
    category = models.ForeignKey(Category, related_name='items')

    def __unicode__(self):

    def category_name(self):

Your serializer would look like this. Note that the serializer will automatically get the value of the category_name model property by naming the field with the same name.

class ItemSerializer(serializers.ModelSerializer):
    category_name = serializers.ReadOnlyField()

    class Meta:
        model = Item

How to save a git commit message from windows cmd?

Press Shift-zz. Saves changes and Quits. Escape didn't work for me.

I am using Git Bash in windows. And couldn't get past this either. My commit messages are simple so I dont want to add another editor atm.

window.location.href doesn't redirect

window.location.href wasn't working in Android. I cleared cache in Android Chrome and it works fine. Suggest trying this first before getting involved in various coding.

Upgrading PHP in XAMPP for Windows?

1) Download new PHP from the official site (better some zip). Old php directory rename to php_old and create again php directory and put there unzipped files.

In php.ini connect needed modules if you used something that was turned off by default (like Memcached etc.), but doesn't forget to add corresponding .dll files.

2) In my case, I had to update Apache. So repeat the same steps: download the new package, rename directories, create new apache directory and put their new files.

Now you can try to restart apache running apache_start.bat from xampp folder (better run this bat, than restart apache service from Windows services window, cause in this case in console you'll see all errors if there will be some, including lines in config where you'll have problem). If you updated Apache and run this file, in the list of services you'll see Apache2.2, but in description you can get another version (in my case that was Apache/2.4.7).

In case of Apache update you can get some problems, so mind:

  • after you replace the whole directory, you may need to configure you apache/conf/httpd.conf file (copy virtual hosts from old config, set up DocumentRoots, permissions for directories, all paths, extend the list of index files (by default apache has only index.html so other index files will be just ignored and Apache will just list the site root directory in browser), configure you logs etc.)

  • connect modules you need (if you used something that was not turned on by default like mod_rewrite etc.)

How to use "/" (directory separator) in both Linux and Windows in Python?

Don't build directory and file names your self, use python's included libraries.

In this case the relevant one is os.path. Especially join which creates a new pathname from a directory and a file name or directory and split that gets the filename from a full path.

Your example would be

p = os.path.join(pathfile, 'output')
p = os.path.join( p, 'log.txt')

C++ Error 'nullptr was not declared in this scope' in Eclipse IDE

Finally found out what to do. Added the -std=c++0x compiler argument under Project Properties -> C/C++ Build -> Settings -> GCC C++ Compiler -> Miscellaneous. It works now!

But how to add this flag by default for all C++ projects? Anybody?

Visual Studio debugging/loading very slow

Deleting .vs folder inside solution folder fixed the slowness for me in VS2019.

Pandas - Get first row value of a given column

To select the ith row, use iloc:

In [31]: df_test.iloc[0]
ATime     1.2
X         2.0
Y        15.0
Z         2.0
Btime     1.2
C        12.0
D        25.0
E        12.0
Name: 0, dtype: float64

To select the ith value in the Btime column you could use:

In [30]: df_test['Btime'].iloc[0]
Out[30]: 1.2

There is a difference between df_test['Btime'].iloc[0] (recommended) and df_test.iloc[0]['Btime']:

DataFrames store data in column-based blocks (where each block has a single dtype). If you select by column first, a view can be returned (which is quicker than returning a copy) and the original dtype is preserved. In contrast, if you select by row first, and if the DataFrame has columns of different dtypes, then Pandas copies the data into a new Series of object dtype. So selecting columns is a bit faster than selecting rows. Thus, although df_test.iloc[0]['Btime'] works, df_test['Btime'].iloc[0] is a little bit more efficient.

There is a big difference between the two when it comes to assignment. df_test['Btime'].iloc[0] = x affects df_test, but df_test.iloc[0]['Btime'] may not. See below for an explanation of why. Because a subtle difference in the order of indexing makes a big difference in behavior, it is better to use single indexing assignment:

df.iloc[0, df.columns.get_loc('Btime')] = x

df.iloc[0, df.columns.get_loc('Btime')] = x (recommended):

The recommended way to assign new values to a DataFrame is to avoid chained indexing, and instead use the method shown by andrew,

df.loc[df.index[n], 'Btime'] = x


df.iloc[n, df.columns.get_loc('Btime')] = x

The latter method is a bit faster, because df.loc has to convert the row and column labels to positional indices, so there is a little less conversion necessary if you use df.iloc instead.

df['Btime'].iloc[0] = x works, but is not recommended:

Although this works, it is taking advantage of the way DataFrames are currently implemented. There is no guarantee that Pandas has to work this way in the future. In particular, it is taking advantage of the fact that (currently) df['Btime'] always returns a view (not a copy) so df['Btime'].iloc[n] = x can be used to assign a new value at the nth location of the Btime column of df.

Since Pandas makes no explicit guarantees about when indexers return a view versus a copy, assignments that use chained indexing generally always raise a SettingWithCopyWarning even though in this case the assignment succeeds in modifying df:

In [22]: df = pd.DataFrame({'foo':list('ABC')}, index=[0,2,1])
In [24]: df['bar'] = 100
In [25]: df['bar'].iloc[0] = 99
/home/unutbu/data/binky/bin/ipython:1: SettingWithCopyWarning: 
A value is trying to be set on a copy of a slice from a DataFrame

See the caveats in the documentation:
  self._setitem_with_indexer(indexer, value)

In [26]: df
  foo  bar
0   A   99  <-- assignment succeeded
2   B  100
1   C  100

df.iloc[0]['Btime'] = x does not work:

In contrast, assignment with df.iloc[0]['bar'] = 123 does not work because df.iloc[0] is returning a copy:

In [66]: df.iloc[0]['bar'] = 123
/home/unutbu/data/binky/bin/ipython:1: SettingWithCopyWarning: 
A value is trying to be set on a copy of a slice from a DataFrame

See the caveats in the documentation:

In [67]: df
  foo  bar
0   A   99  <-- assignment failed
2   B  100
1   C  100

Warning: I had previously suggested df_test.ix[i, 'Btime']. But this is not guaranteed to give you the ith value since ix tries to index by label before trying to index by position. So if the DataFrame has an integer index which is not in sorted order starting at 0, then using ix[i] will return the row labeled i rather than the ith row. For example,

In [1]: df = pd.DataFrame({'foo':list('ABC')}, index=[0,2,1])

In [2]: df
0   A
2   B
1   C

In [4]: df.ix[1, 'foo']
Out[4]: 'C'

jQuery set checkbox checked

This works.

 $("div.row-form input[type='checkbox']").attr('checked','checked');

Update GCC on OSX

I'm just dropping in to say that using a soft link to accomplish this is a terrible, no-good, horrible idea.

One of the key things about writing software is reproduceability - you want to be able to get the same results every time. These systems are so complex that you want to reduce all invisible sources of error.

Having a soft link is an invisible source of error. It's the sort of thing you'll forget in a month, then move to a different machine, and wonder why you are getting different results - or, you'll try to upgrade your system, and you'll get weird errors because it's not expecting a softlink there.

Moreover, this isn't guaranteed to work - in particular, it's not clear that you will get the correct system include files, which have certainly changed between iterations of gcc.

gcc_select is a systematic way of doing the same thing which will work predictably, or in the very worst case you can file a bug report and get an eventual fix or fix it yourself.

Unfortunately :-( gcc_select does not affect which compiler XCode uses so it's not the way to go if you need to work in XCode (which I do). I still don't know what that way might be.

Subtracting Number of Days from a Date in PL/SQL

Use sysdate-1 to subtract one day from system date.

select sysdate, sysdate -1 from dual;


-------- ---------
22-10-13 21-10-13 

How to get Url Hash (#) from server side

Probably the only choice is to read it on the client side and transfer it manually to the server (GET/POST/AJAX). Regards Artur

You may see also how to play with back button and browser history at Malcan

Pyspark: Filter dataframe based on multiple conditions

faster way (without pyspark.sql.functions)

    df.filter((df.d<5)&((df.col1 != df.col3) |
                    (df.col2 != df.col4) & 
                    (df.col1 ==df.col3)))\

Determine file creation date in Java

in java1.7+ You can use this code to get file`s create time !

private static LocalDateTime getCreateTime(File file) throws IOException {
        Path path = Paths.get(file.getPath());
        BasicFileAttributeView basicfile = Files.getFileAttributeView(path, BasicFileAttributeView.class, LinkOption.NOFOLLOW_LINKS);
        BasicFileAttributes attr = basicfile.readAttributes();
        long date = attr.creationTime().toMillis();
        Instant instant = Instant.ofEpochMilli(date);
        return LocalDateTime.ofInstant(instant, ZoneId.systemDefault());

How to convert a String into an ArrayList?

Ok i'm going to extend on the answers here since a lot of the people who come here want to split the string by a whitespace. This is how it's done:

List<String> List = new ArrayList<String>(Arrays.asList(s.split("\\s+")));

How to convert a Base64 string into a Bitmap image to show it in a ImageView?

I have tried all the solutions and this one worked for me

let temp = base64String.components(separatedBy: ",")
let dataDecoded : Data = Data(base64Encoded: temp[1], options: 
let decodedimage = UIImage(data: dataDecoded)

yourImage.image = decodedimage

List of foreign keys and the tables they reference in Oracle DB

Its a bit late to anwser, but I hope my answer been useful for someone, who needs to select Composite foreign keys.


CSS Box Shadow Bottom Only

Try this

-moz-box-shadow:0 5px 5px rgba(182, 182, 182, 0.75);
-webkit-box-shadow: 0 5px 5px rgba(182, 182, 182, 0.75);
box-shadow: 0 5px 5px rgba(182, 182, 182, 0.75);

You can see it in

Change Placeholder Text using jQuery

If the input is inside the div than you can try this:

$('#div_id input').attr("placeholder", "placeholder text");

Click in OK button inside an Alert (Selenium IDE)

This is Pythoncode
Problem with alert boxes (especially sweet-alerts is that they have a delay and Selenium is pretty much too fast)

An Option that worked for me is:

while True:
        driver.find_element_by_xpath('//div[@class="sweet-alert showSweetAlert visible"]')
        wait = WebDriverWait(driver, 1000)

confirm_button = driver.find_element_by_xpath('//button[@class="confirm"]')

What should I do when 'svn cleanup' fails?

I had the exact same problem. I couldn't commit, and cleanup would fail.

Using a command-line client I was able to see an error message indicating that it was failing to move a file from .svn/props to .svn/prop-base.

I looked at the specific file and found that it was marked read-only. After removing the read-only attribute I was able to cleanup the folder and the commit my changes.

If else in stored procedure sql server

You do not have to have the RETURN stament.

Have anther look at Using a Stored Procedure with Output Parameters

Also have another look at the OUT section in CREATE PROCEDURE

Memory errors and list limits?

If you want to circumvent this problem you could also use the shelve. Then you would create files that would be the size of your machines capacity to handle, and only put them on the RAM when necessary, basically writing to the HD and pulling the information back in pieces so you can process it.

Create binary file and check if information is already in it if yes make a local variable to hold it else write some data you deem necessary.

Data ='File01')
   for i in range(0,100):
     Matrix_Shelve = 'Matrix' + str(i)
     if Matrix_Shelve in Data:
        Matrix_local = Data[Matrix_Shelve]
        Data[Matrix_Selve] = 'somenthingforlater'

Hope it doesn't sound too arcaic.

What are WSDL, SOAP and REST?

A WSDL document describes a webservice. It specifies the location of the service and the methods of the service using these major elements: data types using in webservice data elements for each operation describe the operations that can be performed and the messages envolved

SOAP (Simple Object Access Protocol) is a messaging protocol that allows programs that run on disparate operating systems to communicate using http and xml.

Windows batch script to move files

Create a file called MoveFiles.bat with the syntax

move c:\Sourcefoldernam\*.* e:\destinationFolder

then schedule a task to run that MoveFiles.bat every 10 hours.

Changing MongoDB data store directory

Here is what I did, hope it is helpful to anyone else :


  1. Stop your services that are using mongodb
  2. Stop mongod - my way of doing this was with my rc file /etc/rc.d/rc.mongod stop, if you use something else, like systemd you should check your documentation how to do that
  3. Create a new directory on the fresh harddisk - mkdir /mnt/database
  4. Make sure that mongodb has privileges to read / write from that directory ( usually chown mongodb:mongodb -R /mnt/database/mongodb ) - thanks @DanailGabenski.
  5. Copy the data folder of your mongodb to the new location - cp -R /var/lib/mongodb/ /mnt/database/
  6. Remove the old database folder - rm -rf /var/lib/mongodb/
  7. Create symbolic link to the new database folder - ln -s /mnt/database/mongodb /var/lib/mongodb
  8. Start mongod - /etc/rc.d/rc.mongod start
  9. Check the log of your mongod and do some sanity checking ( try mongo to connect to your database to see if everything is all right )
  10. Start your services that you stopped in point 1

There is no need to tell that you should be careful when you do this, especialy with rm -rf but I think this is the best way to do it.

You should never try to copy database dir while mongod is running, because there might be services that write / read from it which will change the content of your database.

How can I refresh a page with jQuery?

This should work on all browsers even without jQuery:


Could not reserve enough space for object heap to start JVM

It looks like the machine you're trying to run this on has only 256 MB memory.

Maybe the JVM tries to allocate a large, contiguous block of 64 MB memory. The 192 MB that you have free might be fragmented into smaller pieces, so that there is no contiguous block of 64 MB free to allocate.

Try starting your Java program with a smaller heap size, for example:

java -Xms16m ...

PLS-00428: an INTO clause is expected in this SELECT statement

In PLSQL block, columns of select statements must be assigned to variables, which is not the case in SQL statements.

The second BEGIN's SQL statement doesn't have INTO clause and that caused the error.

   DSC           VARCHAR (512);
    WHERE PART_NUM = 'S0146404';

             || ','
             || RTRIM (PLANID.DESC_TEXT)
             || ','
             || CASE
                   WHEN PLANID.HIGH = 'TEST123'
                         WHEN TO_DATE (PROD.START_DATE) + 30 > SYSDATE
             || ','
             || 'GB'
             || ','
        INTO DSC
                ON PROD.PART_NUM = PLANID.VAL
                ON PROD.PROD_ID = PROD.ROW_ID
                ON VIS.PROD_ID = VISPROD.ROW_ID
       WHERE     PLANID.TYPE = 'Test Plan'
             AND PLANID.ACTIVE_FLG = 'Y'
             AND PROD.STATUS_CD = 'Active'


How to convert a pandas DataFrame subset of columns AND rows into a numpy array?

.loc accept row and column selectors simultaneously (as do .ix/.iloc FYI) This is done in a single pass as well.

In [1]: df = DataFrame(np.random.rand(4,5), columns = list('abcde'))

In [2]: df
          a         b         c         d         e
0  0.669701  0.780497  0.955690  0.451573  0.232194
1  0.952762  0.585579  0.890801  0.643251  0.556220
2  0.900713  0.790938  0.952628  0.505775  0.582365
3  0.994205  0.330560  0.286694  0.125061  0.575153

In [5]: df.loc[df['c']>0.5,['a','d']]
          a         d
0  0.669701  0.451573
1  0.952762  0.643251
2  0.900713  0.505775

And if you want the values (though this should pass directly to sklearn as is); frames support the array interface

In [6]: df.loc[df['c']>0.5,['a','d']].values
array([[ 0.66970138,  0.45157274],
       [ 0.95276167,  0.64325143],
       [ 0.90071271,  0.50577509]])

maven... Failed to clean project: Failed to delete ..\org.ow2.util.asm-asm-tree-3.1.jar

Maven complains if you do not have admin permissions on the target folder.Check if you have admin right to delete that folder.

enter image description here

How to configure welcome file list in web.xml

Its based on from which file you are trying to access those files.

If it is in the same folder where your working project file is, then you can use just the file name. no need of path.

If it is in the another folder which is under the same parent folder of your working project file then you can use location like in the following /javascript/sample.js

In your example if you are trying to access your js file from your html file you can use the following location


the prefix../ will go to the parent folder of the file(Folder upward journey)

'uint32_t' does not name a type

just navigate to /usr/include/x86_64-linux-gnu/bits open stdint-uintn.h and add these lines

typedef __uint8_t uint8_t;
typedef __uint16_t uint16_t;
typedef __uint32_t uint32_t;
typedef __uint64_t uint64_t;

again open stdint-intn.h and add

typedef __int8_t int8_t;
typedef __int16_t int16_t;
typedef __int32_t int32_t;
typedef __int64_t int64_t;

note these lines are already present just copy and add the missing lines cheerss..

What's the best way to use R scripts on the command line (terminal)?

If the program you're using to execute your script needs parameters, you can put them at the end of the #! line:

#!/usr/bin/R --random --switches --f

Not knowing R, I can't test properly, but this seems to work:

axa@artemis:~$ cat r.test
#!/usr/bin/R -q -f
axa@artemis:~$ ./r.test
> #!/usr/bin/R -q -f
> error
Error: object "error" not found
Execution halted

Resize iframe height according to content height in it

Fitting IFRAME contents is kind of an easy thing to find on Google. Here's one solution:

<script type="text/javascript">
    function autoIframe(frameId) {
       try {
          frame = document.getElementById(frameId);
          innerDoc = (frame.contentDocument) ? frame.contentDocument : frame.contentWindow.document;
          objToResize = ( ? : frame;
          objToResize.height = innerDoc.body.scrollHeight + 10;
       catch(err) {
          window.status = err.message;

This of course doesn't solve the cross-domain problem you are having... Setting document.domain might help if these sites are in the same place. I don't think there is a solution if you are iframe-ing random sites.

CMake error at CMakeLists.txt:30 (project): No CMAKE_C_COMPILER could be found

I had the same errors with CMake. In my case, I have used the wrong Visual Studio version in the initial CMake dialog where we have to select the Visual Studio compiler.

Then I changed it to "Visual Studio 11 2012" and things worked. (I have Visual Studio Ultimate 2012 version on my PC). In general, try to input an older version of Visual Studio version in the initial CMake configuration dialog.

How to customise the Jackson JSON mapper implicitly used by Spring Boot?

You can add a following method inside your bootstrap class which is annotated with @SpringBootApplication

    public ObjectMapper objectMapper(Jackson2ObjectMapperBuilder builder) {
    ObjectMapper objectMapper = builder.createXmlMapper(false).build();
    objectMapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);
    objectMapper.configure(SerializationFeature.WRITE_DATE_TIMESTAMPS_AS_NANOSECONDS, false);

    objectMapper.registerModule(new JodaModule());

    return objectMapper;

What is the max size of localStorage values?

Actually Opera doesn't have 5MB limit. It offers to increase limit as applications requires more. User can even choose "Unlimited storage" for a domain.

You can easily test localStorage limits/quota yourself.

How to unzip a file in Powershell?

Here is a simple way using ExtractToDirectory from System.IO.Compression.ZipFile:

Add-Type -AssemblyName System.IO.Compression.FileSystem
function Unzip
    param([string]$zipfile, [string]$outpath)

    [System.IO.Compression.ZipFile]::ExtractToDirectory($zipfile, $outpath)

Unzip "C:\" "C:\a"

Note that if the target folder doesn't exist, ExtractToDirectory will create it. Other caveats:

See also:

"Rate This App"-link in Google Play store app on the phone

Here is my version using the BuildConfig class:

Intent marketIntent = new Intent(Intent.ACTION_VIEW, uri);



try {
} catch (ActivityNotFoundException e) {
    startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("" + BuildConfig.APPLICATION_ID)));

Finding the number of non-blank columns in an Excel sheet using VBA

Jean-François Corbett's answer is perfect. To be exhaustive I would just like to add that with some restrictons you could also use UsedRange.Columns.Count or UsedRange.Rows.Count.
The problem is that UsedRange is not always updated when deleting rows/columns (at least until you reopen the workbook).

In Java 8 how do I transform a Map<K,V> to another Map<K,V> using a lambda?

The way without re-inserting all entries into the new map should be the fastest it won't because HashMap.clone internally performs rehash as well.

Map<String, Column> newColumnMap = originalColumnMap.clone();
newColumnMap.replaceAll((s, c) -> new Column(c));

C Linking Error: undefined reference to 'main'

You are overwriting your object file runexp.o by running this command :

 gcc -o runexp.o scd.o data_proc.o -lm -fopenmp

In fact, the -o is for the output file. You need to run :

gcc -o runexp.out runexp.o scd.o data_proc.o -lm -fopenmp

runexp.out will be you binary file.

Angular 2 Sibling Component Communication

I have been passing down setter methods from the parent to one of its children through a binding, calling that method with the data from the child component, meaning that the parent component is updated and can then update its second child component with the new data. It does require binding 'this' or using an arrow function though.

This has the benefit that the children aren't so coupled to each other as they don't need a specific shared service.

I am not entirely sure that this is best practice, would be interesting to hear others views on this.

Getting only hour/minute of datetime

Try this:

var src = DateTime.Now;
var hm = new DateTime(src.Year, src.Month, src.Day, src.Hour, src.Minute, 0);

MySQL my.cnf file - Found option without preceding group

Missing config header

Just add [mysqld] as first line in the /etc/mysql/my.cnf file.


default-time-zone = "+08:00"

Afterwards, remember to restart your MySQL Service.

sudo mysqld stop
sudo mysqld start

Upgrade version of Pandas

According to an article on Medium, this will work:

install --upgrade pandas==1.0.0rc0

HTML5 pattern for formatting input box to take date mm/dd/yyyy?


This is pattern to enter the date for textbox in HTML5.
The first one[0-9]{1,2} will take only decimal number minimum 1 and maximum 2.
And other similarly.

"continue" in cursor.forEach()

Here is a solution using for of and continue instead of forEach:

let elementsCollection = SomeElements.find();

for (let el of elementsCollection) {

    // continue will exit out of the current 
    // iteration and continue on to the next
    if (!el.shouldBeProcessed){



This may be a bit more useful if you need to use asynchronous functions inside your loop which do not work inside forEach. For example:

(async fuction(){

for (let el of elementsCollection) {

    if (!el.shouldBeProcessed){

    let res;

    try {
        res = await doSomeLengthyAsyncOperation();
    } catch (err) {
        return Promise.reject(err)



How to get a cross-origin resource sharing (CORS) post request working

I had the exact same issue where jquery ajax only gave me cors issues on post requests where get requests worked fine - I tired everything above with no results. I had the correct headers in my server etc. Changing over to use XMLHTTPRequest instead of jquery fixed my issue immediately. No matter which version of jquery I used it didn't fix it. Fetch also works without issues if you don't need backward browser compatibility.

        var xhr = new XMLHttpRequest()'POST', '', true)
        xhr.withCredentials = true
        xhr.onreadystatechange = function() {
          if (xhr.readyState === 2) {// do something}
        xhr.setRequestHeader('Content-Type', 'application/json')

Hopefully this helps anyone else with the same issues.

How to use a PHP class from another file?

Use include_once instead.
This error means that you have already included this file.


Why is NULL undeclared?

NULL is not a built-in constant in the C or C++ languages. In fact, in C++ it's more or less obsolete, just use a plain literal 0 instead, the compiler will do the right thing depending on the context.

In newer C++ (C++11 and higher), use nullptr (as pointed out in a comment, thanks).

Otherwise, add

#include <stddef.h>

to get the NULL definition.

How to decompile a whole Jar file?

If you happen to have both a bash shell and jad:

JAR=(your jar file name)
unzip -d $JAR.tmp $JAR
pushd $JAR.tmp
for f in `find . -name '*.class'`; do
    jad -d $(dirname $f) -s java -lnc $f

I might be a tiny, tiny bit off with that, but it should work more or less as advertised. You should end up with $JAR.tmp containing your decompiled files.

Slack URL to open a channel from browser

The URI to open a specific channel in Slack app is:


You will probably need these resources of the Slack API to get IDs of your team and channel:

Here's the full documentation from Slack

Get the short Git version hash

Try this:

git rev-parse --short HEAD

The command git rev-parse can do a remarkable number of different things, so you'd need to go through the documentation very carefully to spot that though.

JavaScript and Threads

Another possible method is using an javascript interpreter in the javascript environment.

By creating multiple interpreters and controlling their execution from the main thread, you can simulate multi-threading with each thread running in its own environment.

The approach is somewhat similar to web workers, but you give the interpreter access to the browser global environment.

I made a small project to demonstrate this.

A more detailed explanation in this blog post.

How to print time in format: 2009-08-10 18:17:54.811


    int time_len = 0, n;
    struct tm *tm_info;
    struct timeval tv;

    gettimeofday(&tv, NULL);
    tm_info = localtime(&tv.tv_sec);
    time_len+=strftime(log_buff, sizeof log_buff, "%y%m%d %H:%M:%S", tm_info);
    time_len+=snprintf(log_buff+time_len,sizeof log_buff-time_len,".%03ld ",tv.tv_usec/1000);

CodeIgniter -> Get current URL relative to base url

I see that this post is old. But in version CI v3 here is the answer:

echo $this->uri->uri_string();


Should IBOutlets be strong or weak under ARC?

Be aware, IBOutletCollection should be @property (strong, nonatomic).

Error : getaddrinfo ENOTFOUND

I had the same issue. The reason was the corporate proxy issue. Solution was to set the proxy setting as @rsp says.

npm config set proxy
npm config set https-proxy

But later I face the same issue. This time reason was my password contains a special character.

In this command you can’t provide a password with special character

. So solution is to provide percentage encoded special character in the password.

For example # has to provide as %23

How to output an Excel *.xls file from classic ASP

You must specify the file to be downloaded (attachment) by the client in the http header:

Response.ContentType = "application/"
Response.AppendHeader "content-disposition", "attachment: filename=excelTest.xls"

The meaning of NoInitialContextException error

Do this:

Properties props = new Properties();
props.setProperty(Context.INITIAL_CONTEXT_FACTORY, "com.sun.enterprise.naming.SerialInitContextFactory");
Context initialContext = new InitialContext(props);

Also add this to the libraries of the project:

C:\installs\glassfish\glassfish-4.1\glassfish\lib\gf-client.jar adjust path accordingly

Update Multiple Rows in Entity Framework from a list of ids

something like below

var idList=new int[]{1, 2, 3, 4};
using (var db=new SomeDatabaseContext())
    var friends= db.Friends.Where(f=>idList.Contains(f.ID)).ToList();


you can update multiple fields as below

friends.ForEach(a =>
                         a.property1 = value1;
                         a.property2 = value2;

How do I hide a menu item in the actionbar?

Try this:

MenuItem myitem = menu.findItem(;

Replace spaces with dashes and make all letters lower-case

You can also use split and join:

"Sonic Free Games".split(" ").join("-").toLowerCase(); //sonic-free-games

Using PHP with

Erm, why would you want to? Leave PHP on the backend and NodeJS/Sockets to do its non-blocking thing.

Here is something to get you started:

Personally I have express running with an endpoint that is listening expressly for interaction from PHP.

For example, if I have sent a user an email, I want to display a real-time notification to the user.

Want interaction from to php, well you can just do something like this:

var http = require('http'),
            host = WWW_HOST,
            clen = 'userid=' + userid,
            site = http.createClient(80, host),
            request = site.request("POST", "/modules/nodeim/includes/",  

request.write('userid=' + userid);      

Seriously, PHP is great for doing server side stuff and let it be with the connections it has no place in this domain now. Why do anything long-polling when you have websockets or flashsockets.

How to get current date & time in MySQL?

Even though there are many accepted answers, I think this way is also possible:

Create your 'servers' table as following :

CREATE TABLE `servers`
      id int(11) NOT NULL PRIMARY KEY auto_increment,
      server_name varchar(45) NOT NULL,
      online_status varchar(45) NOT NULL,
      _exchange varchar(45) NOT NULL, 
      disk_space varchar(45) NOT NULL,
      network_shares varchar(45) NOT NULL,

And your INSERT statement should be :

INSERT INTO servers (server_name, online_status, _exchange, disk_space, network_shares)
VALUES('m1', 'ONLINE', 'ONLINE', '100GB', 'ONLINE');

My Environment:

Core i3 Windows Laptop with 4GB RAM, and I did the above example on MySQL Workbench 6.2 (Version Build 397 64 Bits)

Get Selected value from Multi-Value Select Boxes by jquery-select2?

Returns the selected data in structure of object:


Something like:


Returns the selected val:


Something like:

["1", "2"]

$.widget is not a function

Place your widget.js after core.js, but before any other jquery that calls the widget.js file. (Example: draggable.js) Precedence (order) matters in what javascript/jquery can 'see'. Always position helper code before the code that uses the helper code.

Differences between Microsoft .NET 4.0 full Framework and Client Profile

What's new in .NET Framework 4 Client Profile RTM explains many of the differences:

When to use NET4 Client Profile and when to use NET4 Full Framework?
NET4 Client Profile:
Always target NET4 Client Profile for all your client desktop applications (including Windows Forms and WPF apps).

NET4 Full framework:
Target NET4 Full only if the features or assemblies that your app need are not included in the Client Profile. This includes:

  • If you are building Server apps. Such as:
    o ASP.Net apps
    o Server-side ASMX based web services
  • If you use legacy client scenarios. Such as:
    o Use System.Data.OracleClient.dll which is deprecated in NET4 and not included in the Client Profile.
    o Use legacy Windows Workflow Foundation 3.0 or 3.5 (WF3.0 , WF3.5)
  • If you targeting developer scenarios and need tool such as MSBuild or need access to design assemblies such as System.Design.dll

However, as stated on MSDN, this is not relevant for >=4.5:

Starting with the .NET Framework 4.5, the Client Profile has been discontinued and only the full redistributable package is available. Optimizations provided by the .NET Framework 4.5, such as smaller download size and faster deployment, have eliminated the need for a separate deployment package. The single redistributable streamlines the installation process and simplifies your app's deployment options.

android - how to convert int to string and place it in a EditText?

Try using String.format() :

ed = (EditText) findViewById (; 
int x = 10; 

javascript cell number validation

function IsMobileNumber(txtMobId) {
    var mob = /^[1-9]{1}[0-9]{9}$/;
    var txtMobile = document.getElementById(txtMobId);
    if (mob.test(txtMobile.value) == false) {
        alert("Please enter valid mobile number.");
        return false;
    return true;

Calling Validation Mobile Number Function HTML Code -

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

Use srcset

Most current browsers today support the srcset attribute, which allows specifying different images to different users. For example, you can use it for 1x and 2x pixel density, and the browser will select the correct file.

In this case, if you specify an SVG in the srcset and the browser doesn't support it, it'll fallback on the src.

<img src="logo.png" srcset="logo.svg" alt="My logo">

This method has several benefits over other solutions:

  1. It's not relying on any weird hacks or scripts
  2. It's simple
  3. You can still include alt text
  4. Browsers that support srcset should know how to handle it so that it only downloads the file it needs.

How can I customize the tab-to-space conversion factor?

That is lonefy.vscode-js-css-html-formatter to blame. Disable it, and install HookyQR.beautify.

Now on save your tabs wouldn't be converted.

Serialize form data to JSON

If you are sending the form with JSON you must remove [] in the sending string. You can do that with the jQuery function serializeObject():

var frm = $(document.myform);
var data = JSON.stringify(frm.serializeObject());

$.fn.serializeObject = function() {
    var o = {};
    //    var a = this.serializeArray();
    $(this).find('input[type="hidden"], input[type="text"], input[type="password"], input[type="checkbox"]:checked, input[type="radio"]:checked, select').each(function() {
        if ($(this).attr('type') == 'hidden') { //if checkbox is checked do not take the hidden field
            var $parent = $(this).parent();
            var $chb = $parent.find('input[type="checkbox"][name="' +\[/g, '\[').replace(/\]/g, '\]') + '"]');
            if ($chb != null) {
                if ($chb.prop('checked')) return;
        if ( === null || === undefined || === '')
        var elemValue = null;
        if ($(this).is('select'))
            elemValue = $(this).find('option:selected').val();
        else elemValue = this.value;
        if (o[] !== undefined) {
            if (!o[].push) {
                o[] = [o[]];
            o[].push(elemValue || '');
        } else {
            o[] = elemValue || '';
    return o;

Dependency Walker reports IESHIMS.DLL and WER.DLL missing?

ieshims.dll is an artefact of Vista/7 where a shim DLL is used to proxy certain calls (such as CreateProcess) to handle protected mode IE, which doesn't exist on XP, so it is unnecessary. wer.dll is related to Windows Error Reporting and again is probably unused on Windows XP which has a slightly different error reporting system than Vista and above.

I would say you shouldn't need either of them to be present on XP and would normally be delay loaded anyway.

How do I import from Excel to a DataSet using Microsoft.Office.Interop.Excel?

What about using Excel Data Reader (previously hosted here) an open source project on codeplex? Its works really well for me to export data from excel sheets.

The sample code given on the link specified:

FileStream stream = File.Open(filePath, FileMode.Open, FileAccess.Read);

//1. Reading from a binary Excel file ('97-2003 format; *.xls)
IExcelDataReader excelReader = ExcelReaderFactory.CreateBinaryReader(stream);
//2. Reading from a OpenXml Excel file (2007 format; *.xlsx)
IExcelDataReader excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream);
//3. DataSet - The result of each spreadsheet will be created in the result.Tables
DataSet result = excelReader.AsDataSet();
//4. DataSet - Create column names from first row
excelReader.IsFirstRowAsColumnNames = true;
DataSet result = excelReader.AsDataSet();

//5. Data Reader methods
while (excelReader.Read())

//6. Free resources (IExcelDataReader is IDisposable)


After some search around, I came across this article: Faster MS Excel Reading using Office Interop Assemblies. The article only uses Office Interop Assemblies to read data from a given Excel Sheet. The source code is of the project is there too. I guess this article can be a starting point on what you trying to achieve. See if that helps


The code below takes an excel workbook and reads all values found, for each excel worksheet inside the excel workbook.

private static void TestExcel()
        ApplicationClass app = new ApplicationClass();
        Workbook book = null;
        Range range = null;

            app.Visible = false;
            app.ScreenUpdating = false;
            app.DisplayAlerts = false;

            string execPath = Path.GetDirectoryName(Assembly.GetExecutingAssembly().CodeBase);

            book = app.Workbooks.Open(@"C:\data.xls", Missing.Value, Missing.Value, Missing.Value
                                              , Missing.Value, Missing.Value, Missing.Value, Missing.Value
                                             , Missing.Value, Missing.Value, Missing.Value, Missing.Value
                                            , Missing.Value, Missing.Value, Missing.Value);
            foreach (Worksheet sheet in book.Worksheets)

                Console.WriteLine(@"Values for Sheet "+sheet.Index);

                // get a range to work with
                range = sheet.get_Range("A1", Missing.Value);
                // get the end of values to the right (will stop at the first empty cell)
                range = range.get_End(XlDirection.xlToRight);
                // get the end of values toward the bottom, looking in the last column (will stop at first empty cell)
                range = range.get_End(XlDirection.xlDown);

                // get the address of the bottom, right cell
                string downAddress = range.get_Address(
                    false, false, XlReferenceStyle.xlA1,
                    Type.Missing, Type.Missing);

                // Get the range, then values from a1
                range = sheet.get_Range("A1", downAddress);
                object[,] values = (object[,]) range.Value2;

                // View the values
                for (int i = 1; i <= values.GetLength(0); i++)
                    for (int j = 1; j <= values.GetLength(1); j++)
                        Console.Write("{0}\t", values[i, j]);

        catch (Exception e)
            range = null;
            if (book != null)
                book.Close(false, Missing.Value, Missing.Value);
            book = null;
            if (app != null)
            app = null;

In the above code, values[i, j] is the value that you need to be added to the dataset. i denotes the row, whereas, j denotes the column.

What is the best way to initialize a JavaScript Date to midnight?

In case you already have d3.js as a dependency in your project, or don't mind bringing it in, d3-time (d3.js library is modular as of v4.0.0) has got Intervals.

They might prove useful when setting dates to "default" values, e.g. midnight, 0.00 seconds, the first of the month, etc.

var d = new Date(); // Wed Aug 02 2017 15:01:07 GMT+0200 (CEST)
d3.timeHour(d) // Wed Aug 02 2017 00:00:00 GMT+0200 (CEST)
d3.timeMonth(d) // Tue Aug 01 2017 00:00:00 GMT+0200 (CEST)

Preferred way of loading resources in Java

I search three places as shown below. Comments welcome.

public URL getResource(String resource){

    URL url ;

    //Try with the Thread Context Loader. 
    ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
    if(classLoader != null){
        url = classLoader.getResource(resource);
        if(url != null){
            return url;

    //Let's now try with the classloader that loaded this class.
    classLoader = Loader.class.getClassLoader();
    if(classLoader != null){
        url = classLoader.getResource(resource);
        if(url != null){
            return url;

    //Last ditch attempt. Get the resource from the classpath.
    return ClassLoader.getSystemResource(resource);

How to present UIActionSheet iOS Swift?

Code for adding alerts to actionsheet in swift4

   *That means when we click actionsheet values(like edit/ on) it shows 
   an alert option that is set with Yes or No option*

   class ViewController: UIViewController

override func viewDidLoad() {
    // Do any additional setup after loading the view, typically from a nib.

@IBAction func action_sheet1(_ sender: Any) {

    let action_sheet1 = UIAlertController(title: "Hi Bro", message: "Please Select an Option: ", preferredStyle: .actionSheet)

    action_sheet1.addAction(UIAlertAction(title: "Approve", style: .default , handler:{ (alert: UIAlertAction!) -> Void in
        print("User click Approve button")

        let alert = UIAlertController(title: "Approve", message: "Would you like to approve the file ", preferredStyle: UIAlertController.Style.alert)

        alert.addAction(UIAlertAction(title: "Yes", style: UIAlertAction.Style.default, handler: nil))

        alert.addAction(UIAlertAction(title: "No", style: UIAlertAction.Style.default, handler: nil))

        self.present(alert, animated: true, completion: nil)


    action_sheet1.addAction(UIAlertAction(title: "Edit", style: .default , handler:{ (alert: UIAlertAction!) -> Void in
        print("User click Edit button")

        let alert = UIAlertController(title: "Edit", message: "Would you like to edit the file ", preferredStyle: UIAlertController.Style.alert)

        alert.addAction(UIAlertAction(title: "Yes", style: UIAlertAction.Style.default, handler: nil))

        alert.addAction(UIAlertAction(title: "No", style: UIAlertAction.Style.default, handler: nil))

        self.present(alert, animated: true, completion: nil)


    action_sheet1.addAction(UIAlertAction(title: "Delete", style: .destructive , handler: { (alert: UIAlertAction!) -> Void in
        print("User click Delete button")

        let alert = UIAlertController(title: "Delete", message: "Would you like to delete the file permenently?", preferredStyle: UIAlertController.Style.alert)

        alert.addAction(UIAlertAction(title: "Yes", style: UIAlertAction.Style.default, handler: nil))

        alert.addAction(UIAlertAction(title: "No", style: UIAlertAction.Style.default, handler: nil))

        self.present(alert, animated: true, completion: nil)


    action_sheet1.addAction(UIAlertAction(title: "cancel", style: .cancel, handler:{ (alert: UIAlertAction!) -> Void in
         print("User click cancel button")

        let alert = UIAlertController(title: "Cancel", message: "Would you like to cancel?", preferredStyle: UIAlertController.Style.alert)

        alert.addAction(UIAlertAction(title: "Yes", style: UIAlertAction.Style.default, handler: nil))

        alert.addAction(UIAlertAction(title: "No", style: UIAlertAction.Style.default, handler: nil))

        self.present(alert, animated: true, completion: nil)


        self.present(action_sheet1, animated: true, completion: {
        print("completion block")


How to force cp to overwrite without confirmation

You probably have an alias somewhere, mapping cp to cp -i; because with the default settings, cp won't ask to overwrite. Check your .bashrc, your .profile etc.

See cp manpage: Only when -i parameter is specified will cp actually prompt before overwriting.

You can check this via the alias command:

$ alias
alias cp='cp -i'
alias diff='diff -u'

To undefine the alias, use:

$ unalias cp

Sibling package imports

You need to look to see how the import statements are written in the related code. If examples/ uses the following import statement:

import api.api

...then it expects the root directory of the project to be in the system path.

The easiest way to support this without any hacks (as you put it) would be to run the examples from the top level directory, like this:

PYTHONPATH=$PYTHONPATH:. python examples/ 

Loop timer in JavaScript

Note that setTimeout and setInterval are very different functions:

  • setTimeout will execute the code once, after the timeout.
  • setInterval will execute the code forever, in intervals of the provided timeout.

Both functions return a timer ID which you can use to abort the timeout. All you have to do is store that value in a variable and use it as argument to clearTimeout(tid) or clearInterval(tid) respectively.

So, depending on what you want to do, you have two valid choices:

// set timeout
var tid = setTimeout(mycode, 2000);
function mycode() {
  // do some stuff...
  tid = setTimeout(mycode, 2000); // repeat myself
function abortTimer() { // to be called when you want to stop the timer


// set interval
var tid = setInterval(mycode, 2000);
function mycode() {
  // do some stuff...
  // no need to recall the function (it's an interval, it'll loop forever)
function abortTimer() { // to be called when you want to stop the timer

Both are very common ways of achieving the same.

How to create a zip file in Java

There is another option by using zip4j at

Creating a zip file with single file in it / Adding single file to an existing zip

new ZipFile("").addFile("filename.ext"); Or

new ZipFile("").addFile(new File("filename.ext"));

Creating a zip file with multiple files / Adding multiple files to an existing zip

new ZipFile("").addFiles(Arrays.asList(new File("first_file"), new File("second_file")));

Creating a zip file by adding a folder to it / Adding a folder to an existing zip

new ZipFile("").addFolder(new File("/user/myuser/folder_to_add"));

Creating a zip file from stream / Adding a stream to an existing zip new ZipFile("").addStream(inputStream, new ZipParameters());

Generate an integer that is not among four billion given ones

For the 10 MB memory constraint:

  1. Convert the number to its binary representation.
  2. Create a binary tree where left = 0 and right = 1.
  3. Insert each number in the tree using its binary representation.
  4. If a number has already been inserted, the leafs will already have been created.

When finished, just take a path that has not been created before to create the requested number.

4 billion number = 2^32, meaning 10 MB might not be sufficient.


An optimization is possible, if two ends leafs have been created and have a common parent, then they can be removed and the parent flagged as not a solution. This cuts branches and reduces the need for memory.


There is no need to build the tree completely too. You only need to build deep branches if numbers are similar. If we cut branches too, then this solution might work in fact.

Set width of a "Position: fixed" div relative to parent div

Use this CSS:

#container {
    width: 400px;
    border: 1px solid red;

#fixed {
    position: fixed;
    width: inherit;
    border: 1px solid green;

The #fixed element will inherit it's parent width, so it will be 100% of that.

How to find if a file contains a given string using Windows command line

From other post:

    find /c "string" file >NUL
    if %errorlevel% equ 1 goto notfound
        echo found
    goto done
        echo notfound
    goto done

Use the /i switch when you want case insensitive checking:

    find /i /c "string" file >NUL

Or something like: if not found write to file.

    find /c "%%P" file.txt  || ( echo %%P >> newfile.txt )

Or something like: if found write to file.

    find /c "%%P" file.txt  && ( echo %%P >> newfile.txt )

Or something like:

    find /c "%%P" file.txt  && ( echo found ) || ( echo not found )

What does `m_` variable prefix mean?

One argument that I haven't seen yet is that a prefix such as m_ can be used to prevent name clashing with #define'd macro's.

Regex search for #define [a-z][A-Za-z0-9_]*[^(] in /usr/include/term.h from curses/ncurses.


WHERE clause is used to eliminate the tuples in a relation,and HAVING clause is used to eliminate the groups in a relation.

HAVING clause is used for aggregate functions such as MIN,MAX,COUNT,SUM .But always use GROUP BY clause before HAVING clause to minimize the error.

Difference between id and name attributes in HTML

The id will give an element a id, so once you write real code, (like JavaScript) you can use the id to read elements. The name is just a name so the user can see the name of the element, I guess.


<h1 id="heading">text</h1>
  document.getElementById("heading"); //Reads the element that has the id "heading".
//You can also use something like this:
document.getElementById("heading").value; //Reads the value of the selected element.

Is it helpful? Let me know if there is some problems.

What does the "More Columns than Column Names" error mean?

Depending on the data (e.g. tsv extension) it may use tab as separators, so you may try sep = '\t' with read.csv.

Validate that end date is greater than start date with jQuery

If the format is guaranteed to be correct YYYY/MM/DD and exactly the same between the two fields then you can use:

if (startdate > enddate) {

As a string comparison

Rotate and translate

Something that may get missed: in my chaining project, it turns out a space separated list also needs a space separated semicolon at the end.

In other words, this doesn't work:

transform: translate(50%, 50%) rotate(90deg);

but this does:

transform: translate(50%, 50%) rotate(90deg) ; //has a space before ";"

Convert pem key to ssh-rsa format

I did with

ssh-keygen -i -f $sshkeysfile >> authorized_keys

Credit goes here

How do I plot in real-time in a while loop using matplotlib?

I know this question is old, but there's now a package available called drawnow on GitHub as "python-drawnow". This provides an interface similar to MATLAB's drawnow -- you can easily update a figure.

An example for your use case:

import matplotlib.pyplot as plt
from drawnow import drawnow

def make_fig():
    plt.scatter(x, y)  # I think you meant this

plt.ion()  # enable interactivity
fig = plt.figure()  # make a figure

x = list()
y = list()

for i in range(1000):
    temp_y = np.random.random()
    y.append(temp_y)  # or any arbitrary update to your figure's data
    i += 1

python-drawnow is a thin wrapper around plt.draw but provides the ability to confirm (or debug) after figure display.

Debugging WebSocket in Google Chrome

I have used Chrome extension called Simple WebSocket Client v0.1.3 that is published by user hakobera. It is very simple in its usage where it allows opening websockets on a given URL, send messages and close the socket connection. It is very minimalistic.


Just looking at the message it sounds like one or more of the components that you reference, or one or more of their dependencies is not registered properly.

If you know which component it is you can use regsvr32.exe to register it, just open a command prompt, go to the directory where the component is and type regsvr32 filename.dll (assuming it's a dll), if it works, try to run the code again otherwise come back here with the error.

If you don't know which component it is, try re-installing/repairing the GIS software (I assume you've installed some GIS software that includes the component you're trying to use).

How to create a JSON object

$post_data = [
  "item" => [
    'item_type_id' => $item_type,
    'string_key' => $string_key,
    'string_value' => $string_value,
    'string_extra' => $string_extra,
    'is_public' => $public,
    'is_public_for_contacts' => $public_contacts

$post_data = json_encode(post_data);
$post_data = json_decode(post_data);
return $post_data;

using CASE in the WHERE clause

FROM logs
WHERE pw='correct'
          WHEN id<800 THEN success=1
          ELSE 1=1

Formatting NSDate into particular styles for both year, month, day, and hour, minute, seconds

nothing new but still want to share my method:

+(NSString*) getDateStringFromSrcFormat:(NSString *) srcFormat destFormat:(NSString *)
destFormat scrString:(NSString *) srcString
    NSString *dateString = srcString;
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    //[dateFormatter setDateFormat:@"MM-dd-yyyy"];
    [dateFormatter setDateFormat:srcFormat];
    NSDate *date = [dateFormatter dateFromString:dateString];

    // Convert date object into desired format
    //[dateFormatter setDateFormat:@"yyyy-MM-dd"];
    [dateFormatter setDateFormat:destFormat];
    NSString *newDateString = [dateFormatter stringFromDate:date];
    return newDateString;

submitting a form when a checkbox is checked

You can submit form by just clicking on checkbox by simple method in JavaScript. Inside form tag or Input attribute add following attribute:



           <input type="checkbox">

For a boolean field, what is the naming convention for its getter/setter?

For a field named isCurrent, the correct getter / setter naming is setCurrent() / isCurrent() (at least that's what Eclipse thinks), which is highly confusing and can be traced back to the main problem:

Your field should not be called isCurrent in the first place. Is is a verb and verbs are inappropriate to represent an Object's state. Use an adjective instead, and suddenly your getter / setter names will make more sense:

private boolean current;

public boolean isCurrent(){
    return current;

public void setCurrent(final boolean current){
    this.current = current;

Run PHP Task Asynchronously

It's a great idea to use cURL as suggested by rojoca.

Here is an example. You can monitor text.txt while the script is running in background:


function doCurl($begin)
    echo "Do curl<br />\n";
    $url = 'http://'.$_SERVER['SERVER_NAME'].$_SERVER['REQUEST_URI'];
    $url = preg_replace('/\?.*/', '', $url);
    $url .= '?begin='.$begin;
    echo 'URL: '.$url.'<br>';
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $result = curl_exec($ch);
    echo 'Result: '.$result.'<br>';

if (empty($_GET['begin'])) {
else {
    while (ob_get_level())
    header('Connection: close');
    echo 'Connection Closed';
    $size = ob_get_length();
    header("Content-Length: $size");

    $begin = $_GET['begin'];
    $fp = fopen("text.txt", "w");
    fprintf($fp, "begin: %d\n", $begin);
    for ($i = 0; $i < 15; $i++) {
        fprintf($fp, "i: %d\n", $i);
    if ($begin < 10)
        doCurl($begin + 1);


Xcode build failure "Undefined symbols for architecture x86_64"

For me, this started to happen after merge conflict.

I tried to clean and remove build folder, but none of it helped. This issue kept happening regardless. Then I relinked the reference by deleting the groups that was problematic and re-added to the project and it worked.

Adding a background image to a <div> element

<div id="image">Example to have Background Image</div>

We need to Add the below content in Style tag:

.image {
  background-image: url('C:\Users\ajai\Desktop\10.jpg');

JavaScript adding decimal numbers issue

function add(){
    var first=parseFloat($("#first").val());
    var second=parseFloat($("#second").val());


"unable to locate adb" using Android Studio

if using avast go for virus chest,will find adb,restore it by clicking right button..thats all,perfectly works

How do I redirect with JavaScript?

  • If you want to simulate someone clicking on a link, use location.href.
  • If you want to simulate an HTTP redirect, use location.replace.

For example:

// Similar behavior as an HTTP redirect

// Similar behavior as clicking on a link
window.location.href = "";

Information copied from this answer to a duplicate question

Unit Tests not discovered in Visual Studio 2017

In my case, it turned out that I simply had to upgrade my test adapters and test framework. Done.

Example using the NuGet Package Manager:

enter image description here

How to update ruby on linux (ubuntu)?

Generally the verions of programs are linked to the version of your operating system. So if you were running gutsy you would either have to upgrade to the new jaunty jackalope version which has ruby 1.9 or add the respoistories for jaunty to your /etc/apt/sources.list file. Once you have done that you can start up the synaptic package manager and you should see it in there.

Using awk to print all columns from the nth to the last

I wasn't happy with any of the awk solutions presented here because I wanted to extract the first few columns and then print the rest, so I turned to perl instead. The following code extracts the first two columns, and displays the rest as is:

echo -e "a  b  c  d\te\t\tf g" | \
  perl -ne 'my @f = split /\s+/, $_, 3; printf "first: %s second: %s rest: %s", @f;'

The advantage compared to the perl solution from Chris Koknat is that really only the first n elements are split off from the input string; the rest of the string isn't split at all and therefor stays completely intact. My example demonstrates this with a mix of spaces and tabs.

To change the amount of columns that should be extracted, replace the 3 in the example with n+1.

Passing data between view controllers

There are tons of ways to do this and it's important to pick the right one. Probably one of the biggest architectural decisions lies on how the model code will be shared or accessed throughout the app.

I wrote a blog post about this a while back: Sharing Model Code. Here's a brief summary:

Shared data

One approach is to share pointers to the model objects between view controllers.

  • Brute force iteration on view controllers (in Navigation or Tab Bar Controller) to set the data
  • Set data in prepareForSegue (if storyboards) or init (if programmatic)

Since prepare for segue is the most common here is an example:

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    var next = segue.destinationViewController as NextViewController
    next.dataSource = dataSource

Independent access

Another approach is to handle a screen full of data at a time and instead of coupling the view controllers to each other couple each view controller to single data source that they can get to independently.

The most common way I've seen this done is a singleton instance. So if your singleton object was DataAccess you could do the following in the viewDidLoad method of UIViewController:

func viewDidLoad() {
    var data = dataAccess.requestData()

There are addition tools that also help pass along data:

  • Key-Value Observing
  • NSNotification
  • Core Data
  • NSFetchedResultsController
  • Data Source

Core Data

The nice thing about Core Data is that it has inverse relationships. So if you want to just give a NotesViewController the notes object you can because it'll have an inverse relationship to something else like the notebook. If you need data on the notebook in the NotesViewController you can walk back up the object graph by doing the following:

let notebookName =

Read more about this in my blog post: Sharing Model Code

How to split a string with any whitespace chars as delimiters

Something in the lines of


This groups all white spaces as a delimiter.

So if I have the string:

"Hello[space character][tab character]World"

This should yield the strings "Hello" and "World" and omit the empty space between the [space] and the [tab].

As VonC pointed out, the backslash should be escaped, because Java would first try to escape the string to a special character, and send that to be parsed. What you want, is the literal "\s", which means, you need to pass "\\s". It can get a bit confusing.

The \\s is equivalent to [ \\t\\n\\x0B\\f\\r].

How to get exception message in Python properly

I had the same problem. I think the best solution is to use log.exception, which will automatically print out stack trace and error message, such as:


JQuery Event for user pressing enter in a textbox?

heres a jquery plugin to do that

(function($) {
    $.fn.onEnter = function(func) {
        this.bind('keypress', function(e) {
            if (e.keyCode == 13) func.apply(this, [e]);    
        return this; 

to use it, include the code and set it up like this:

$( function () {
    $("input").onEnter( function() {
        $(this).val("Enter key pressed");                

jsfiddle of it here

How do I write a batch script that copies one directory to another, replaces old files?

Have you considered using the "xcopy" command?

The xcopy command will do all that for you.

Ajax post request in laravel 5 return error 500 (Internal Server Error)

You can add your URLs to VerifyCsrfToken.php middleware. The URLs will be excluded from CSRF verification.

protected $except = [
    "your url",
    "your url/abc"

Why does using an Underscore character in a LIKE filter give me all the results?

In case people are searching how to do it in BigQuery:

  • An underscore "_" matches a single character or byte.

  • You can escape "\", "_", or "%" using two backslashes. For example, "\%". If you are using raw strings, only a single backslash is required. For example, r"\%".

WHERE mycolumn LIKE '%\\_%'


How to zip a file using cmd line?

ZIP FILE via Cross-platform Java without manifest and META-INF folder:

jar -cMf {} {yourfolder}

Finding repeated words on a string and counting the repetitions

Try this,

public class DuplicateWordSearcher {
public static void main(String[] args) {

    String text = "a r b k c d se f g a d f s s f d s ft gh f ws w f v x s g h d h j j k f sd j e wed a d f";

    List<String> list = Arrays.asList(text.split(" "));

    Set<String> uniqueWords = new HashSet<String>(list);
    for (String word : uniqueWords) {
        System.out.println(word + ": " + Collections.frequency(list, word));


Check if Key Exists in NameValueCollection

I am using this collection, when I worked in small elements collection.

Where elements lot, I think need use "Dictionary". My code:

NameValueCollection ProdIdes;
string prodId = _cfg.ProdIdes[key];
if (string.IsNullOrEmpty(prodId))

Or may be use this:

 string prodId = _cfg.ProdIdes[key] !=null ? "found" : "not found";

How SID is different from Service name in Oracle tnsnames.ora

Quote by @DAC

In short: SID = the unique name of your DB, ServiceName = the alias used when connecting

Not strictly true. SID = unique name of the INSTANCE (eg the oracle process running on the machine). Oracle considers the "Database" to be the files.

Service Name = alias to an INSTANCE (or many instances). The main purpose of this is if you are running a cluster, the client can say "connect me to", the DBA can on the fly change the number of instances which are available to requests, or even move to a completely different database without the client needing to change any settings.

Make columns of equal width in <table>

Use following property same as table and its fully dynamic:

ul {_x000D_
    width: 100%;_x000D_
    display: table;_x000D_
    table-layout: fixed; /* optional, for equal spacing */_x000D_
    border-collapse: collapse;_x000D_
li {_x000D_
    display: table-cell;_x000D_
    text-align: center;_x000D_
    border: 1px solid pink;_x000D_
    vertical-align: middle;_x000D_
  <li>baz klxjgkldjklg </li>_x000D_
  <li>baz lds.jklklds</li>_x000D_

May be its solve your issue.

Using jQuery how to get click coordinates on the target element

see here enter link description here


<p>This is a paragraph.</p>
<div id="myPosition">




       var elm = $(this);
       var xPos = e.pageX - elm.offset().left;
       var yPos = e.pageY - elm.offset().top;
       alert("X position: " + xPos + ", Y position: " + yPos);

Convert Int to String in Swift

Swift 2:

var num1 = 4
var numString = "56"
var sum2 = String(num1) + numString
var sum3 = Int(numString)

Multiple Errors Installing Visual Studio 2015 Community Edition

For some reason the installation broke while in process. After this, nothing helped and repair/unistall only produced package errors. What finally helped was this thing:

after I ran it a couple times (it didn't remove everything on the first I was finally able to start a fresh installation and it worked.

How to set textColor of UILabel in Swift

The easiest workaround is create dummy labels in IB, give them the text the color you like and set to hidden. You can then reference this color in your code to set your label to the desired color.

yourLabel.textColor = hiddenLabel.textColor

The only way I could change the text color programmatically was by using the standard colors, UIColor.white,

Docker command can't connect to Docker daemon

Tested in Ubuntu 16.04

# Create the docker group and add your user to the docker group
groupadd docker
usermod -aG docker $USER
newgrp docker

# Configure docker service to be exposed
mkdir -p /etc/systemd/system/docker.service.d
echo -e '[Service]\nExecStart=\nExecStart=/usr/bin/dockerd -H fd:// -H tcp://' >> /etc/systemd/system/docker.service.d/override.conf

# restart service
systemctl daemon-reload
service docker restart

Android view pager with page indicator

I have also used the SimpleViewPagerIndicator from @JROD. It also crashes as described by @manuelJ.

According to his documentation:

SimpleViewPagerIndicator pageIndicator = (SimpleViewPagerIndicator) findViewById(;

Make sure you add this line as well:


It crashes with an array out of bounds exception because the SimpleViewPagerIndicator is not getting instantiated properly and the items are empty. Calling the notifyDataSetChanged results in all the values being set properly or rather reset properly.

How do I change the value of a global variable inside of a function

Just reference the variable inside the function; no magic, just use it's name. If it's been created globally, then you'll be updating the global variable.

You can override this behaviour by declaring it locally using var, but if you don't use var, then a variable name used in a function will be global if that variable has been declared globally.

That's why it's considered best practice to always declare your variables explicitly with var. Because if you forget it, you can start messing with globals by accident. It's an easy mistake to make. But in your case, this turn around and becomes an easy answer to your question.

How do I wait until Task is finished in C#?

A clean example that answers the Title

string output = "Error";
Task task = Task.Factory.StartNew(() =>
    output = "Complete";


Switch statement fall-through...should it be allowed?

It can be very useful a few times, but in general, no fall-through is the desired behavior. Fall-through should be allowed, but not implicit.

An example, to update old versions of some data:

switch (version) {
    case 1:
        // Update some stuff
    case 2:
        // Update more stuff
    case 3:
        // Update even more stuff
    case 4:
        // And so on

How to get city name from latitude and longitude coordinates in Google Maps?

I am using this code. You can also your this for getting city and other details about a Latitude and longitude :

public class getReverseGeoCoding {
    private String Address1 = "", Address2 = "", City = "", State = "", Country = "", County = "", PIN = "";
    public void getAddress() {
        Address1 = "";
        Address2 = "";
        City = "";
        State = "";
        Country = "";
        County = "";
        PIN = "";
        try {
            JSONObject jsonObj = parser_Json.getJSONfromURL("" + Global.curLatitude + ","
                    + Global.curLongitude + "&sensor=true&key=YOUR_API_KEY");
            String Status = jsonObj.getString("status");
            if (Status.equalsIgnoreCase("OK")) {
                JSONArray Results = jsonObj.getJSONArray("results");
                JSONObject zero = Results.getJSONObject(0);
                JSONArray address_components = zero.getJSONArray("address_components");
                for (int i = 0; i < address_components.length(); i++) {
                    JSONObject zero2 = address_components.getJSONObject(i);
                    String long_name = zero2.getString("long_name");
                    JSONArray mtypes = zero2.getJSONArray("types");
                    String Type = mtypes.getString(0);
                    if (TextUtils.isEmpty(long_name) == false || !long_name.equals(null) || long_name.length() > 0 || long_name != "") {
                        if (Type.equalsIgnoreCase("street_number")) {
                            Address1 = long_name + " ";
                        } else if (Type.equalsIgnoreCase("route")) {
                            Address1 = Address1 + long_name;
                        } else if (Type.equalsIgnoreCase("sublocality")) {
                            Address2 = long_name;
                        } else if (Type.equalsIgnoreCase("locality")) {
                            // Address2 = Address2 + long_name + ", ";
                            City = long_name;
                        } else if (Type.equalsIgnoreCase("administrative_area_level_2")) {
                            County = long_name;
                        } else if (Type.equalsIgnoreCase("administrative_area_level_1")) {
                            State = long_name;
                        } else if (Type.equalsIgnoreCase("country")) {
                            Country = long_name;
                        } else if (Type.equalsIgnoreCase("postal_code")) {
                            PIN = long_name;
                    // JSONArray mtypes = zero2.getJSONArray("types");
                    // String Type = mtypes.getString(0);
                    // Log.e(Type,long_name);
        } catch (Exception e) {
    public String getAddress1() {
        return Address1;
    public String getAddress2() {
        return Address2;
    public String getCity() {
        return City;
    public String getState() {
        return State;
    public String getCountry() {
        return Country;
    public String getCounty() {
        return County;
    public String getPIN() {
        return PIN;

For more detail on how to get Google Map Api key


public class parser_Json {
    public static JSONObject getJSONfromURL(String url) {

        // initialize
        InputStream is = null;
        String result = "";
        JSONObject jObject = null;

        // http post
        try {
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost(url);
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();
            is = entity.getContent();

        } catch (Exception e) {
            Log.e("log_tag", "Error in http connection " + e.toString());

        // convert response to string
        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            result = sb.toString();
        } catch (Exception e) {
            Log.e("log_tag", "Error converting result " + e.toString());

        // try parse the string to a JSON object
        try {
            jObject = new JSONObject(result);
        } catch (JSONException e) {
            Log.e("log_tag", "Error parsing data " + e.toString());

        return jObject;


You can get more info from this question : Get the particular address using latitude and longitude

create a white rgba / CSS3

I believe

rgba( 0, 0, 0, 0.8 )

is equivalent in shade with #333.

Live demo:

CSS last-child selector: select last-element of specific class, not last child inside of parent?

:last-child only works when the element in question is the last child of the container, not the last of a specific type of element. For that, you want :last-of-type

As per @BoltClock's comment, this is only checking for the last article element, not the last element with the class of .comment.

body {_x000D_
  background: black;_x000D_
.comment {_x000D_
  width: 470px;_x000D_
  border-bottom: 1px dotted #f0f0f0;_x000D_
  margin-bottom: 10px;_x000D_
.comment:last-of-type {_x000D_
  border-bottom: none;_x000D_
  margin-bottom: 0;_x000D_
<div class="commentList">_x000D_
  <article class="comment " id="com21"></article>_x000D_
  <article class="comment " id="com20"></article>_x000D_
  <article class="comment " id="com19"></article>_x000D_
  <div class="something"> hello </div>_x000D_

How do I prevent and/or handle a StackOverflowException?

From Microsoft:

Starting with the .NET Framework version 2.0, a StackOverflowException object cannot be caught by a try-catch block and the corresponding process is terminated by default. Consequently, users are advised to write their code to detect and prevent a stack overflow. For example, if your application depends on recursion, use a counter or a state condition to terminate the recursive loop.

I'm assuming the exception is happening within an internal .NET method, and not in your code.

You can do a couple things.

  • Write code that checks the xsl for infinite recursion and notifies the user prior to applying a transform (Ugh).
  • Load the XslTransform code into a separate process (Hacky, but less work).

You can use the Process class to load the assembly that will apply the transform into a separate process, and alert the user of the failure if it dies, without killing your main app.

EDIT: I just tested, here is how to do it:


// This is just an example, obviously you'll want to pass args to this.
Process p1 = new Process();
p1.StartInfo.FileName = "ApplyTransform.exe";
p1.StartInfo.UseShellExecute = false;
p1.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;


if (p1.ExitCode == 1)    
   Console.WriteLine("StackOverflow was thrown");

ApplyTransform Process:

class Program
    static void Main(string[] args)
        AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
        throw new StackOverflowException();

    // We trap this, we can't save the process, 
    // but we can prevent the "ILLEGAL OPERATION" window 
    static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
        if (e.IsTerminating)

How to position the div popup dialog to the center of browser screen?

You can use CSS3 'transform':


  background-color: rgba(102, 102, 102, .5);
  position: fixed;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  z-index: 10;
  background-color: white;
  position: fixed;
  top: 50%;
  left: 50%;
  z-index: 11;
-webkit-transform: translate(-50%, -50%);
-moz-transform: translate(-50%, -50%);
-ms-transform: translate(-50%, -50%);
-o-transform: translate(-50%, -50%);
transform: translate(-50%, -50%);


<div class="popup-bck"></div>
<div class="popup-content-box">
Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. 

*so you don't have to use margin-left: -width/2 px;

How to send email from localhost WAMP Server to send email Gmail Hotmail or so forth?

Configuring a working email client from localhost is quite a chore, I have spent hours of frustration attempting it. At last I have found this way to send mails (using WAMP, XAMPP, etc.):

Install hMailServer

Configure this hMailServer setting:

  1. Open hMailServer Administrator.
  2. Click the "Add domain ..." button to create a new domain.
  3. Under the domain text field, enter your computer's localhost IP.
    • Example: is your localhost IP.
  4. Click the "Save" button.
  5. Now go to Settings > Protocols > SMTP and select the "Delivery of Email" tab.
  6. Find the localhost field enter "localhost".
  7. Click the Save button.

Configure your Gmail account, perform following modification:

  1. Go to Settings > Protocols > SMTP and select "Delivery of Email" tab.
  2. Enter "" in the Remote Host name field.
  3. Enter "465" as the port number.
  4. Check "Server requires authentication".
  5. Enter your Google Mail address in the Username field.
  6. Enter your Google Mail password in the password field.
  7. Check mark "Use SSL"
  8. Save all changes.


If you want to send email from another computer you need to allow deliveries from External to External accounts by following steps:

  1. Go to Settings > Advanced > IP Ranges and double click on "My Computer" which should have IP address of
  2. Check the Allow Deliveries from External to External accounts Checkbox.
  3. Save settings using Save button.

What is the best way to get the count/length/size of an iterator?

iterator object contains the same number of elements what your collection contained.

List<E> a =...;
Iterator<E> i = a.iterator();
int size = a.size();//Because iterators size is equal to list a's size.

But instead of getting the size of iterator and iterating through index 0 to that size, it is better to iterate through the method next() of the iterator.

Duplicating a MySQL table, indices, and data

To copy with indexes and triggers do these 2 queries:

CREATE TABLE newtable LIKE oldtable; 
INSERT INTO newtable SELECT * FROM oldtable;

To copy just structure and data use this one:

CREATE TABLE tbl_new AS SELECT * FROM tbl_old;

I've asked this before:

Copy a MySQL table including indexes

How to make/get a multi size .ico file?

Visual Studio Resource Editor (free as VS 2013 Community edition) can import PNG (and other formats) and export ICO.

Strings in C, how to get subString

#include <string.h>
char otherString[6]; // note 6, not 5, there's one there for the null terminator
strncpy(otherString, someString, 5);
otherString[5] = '\0'; // place the null terminator

Method to Add new or update existing item in Dictionary

Could there be any problem if i replace Method-1 by Method-2?

No, just use map[key] = value. The two options are equivalent.

Regarding Dictionary<> vs. Hashtable: When you start Reflector, you see that the indexer setters of both classes call this.Insert(key, value, add: false); and the add parameter is responsible for throwing an exception, when inserting a duplicate key. So the behavior is the same for both classes.

Using a global variable with a thread

Well, running example:


Use semaphores, shared variables, etc. to avoid rush conditions.

from threading import Thread
import time

a = 0  # global variable

def thread1(threadname):
    global a
    for k in range(100):
        print("{} {}".format(threadname, a))
        if k == 5:
            a += 100

def thread2(threadname):
    global a
    for k in range(10):
        a += 1

thread1 = Thread(target=thread1, args=("Thread-1",))
thread2 = Thread(target=thread2, args=("Thread-2",))



and the output:

Thread-1 0
Thread-1 1
Thread-1 2
Thread-1 2
Thread-1 3
Thread-1 3
Thread-1 104
Thread-1 104
Thread-1 105
Thread-1 105
Thread-1 106
Thread-1 106
Thread-1 107
Thread-1 107
Thread-1 108
Thread-1 108
Thread-1 109
Thread-1 109
Thread-1 110
Thread-1 110
Thread-1 110
Thread-1 110
Thread-1 110
Thread-1 110
Thread-1 110
Thread-1 110

If the timing were right, the a += 100 operation would be skipped:

Processor executes at T a+100 and gets 104. But it stops, and jumps to next thread Here, At T+1 executes a+1 with old value of a, a == 4. So it computes 5. Jump back (at T+2), thread 1, and write a=104 in memory. Now back at thread 2, time is T+3 and write a=5 in memory. Voila! The next print instruction will print 5 instead of 104.

VERY nasty bug to be reproduced and caught.

How to change default JRE for all Eclipse workspaces?

Finally got it: The way Eclipse picks up the JRE is using the system's PATH.

I did not have C:\home\SFTWR\jdk1.6.0_21\bin in the path at all before and I did have C:\Program Files (x86)\Java\jre6\bin. I had both JRE_HOME and JAVA_HOME set to C:\home\SFTWR\jdk1.6.0_21 but neither of those two mattered. I guess Eclipse did (something to the effect of) where java (or which on UNIX/Linux) to see where Java is in the path and took the JRE to which that java.exe belonged. In my case, despite all the configuration tweaks I had done (including eclipse.ini -vm option as suggested above), it remained stuck to what was in the path.

I removed the old JRE bin from the path, put the new one in, and it works for all workspaces.

Count characters in textarea

<script src=""></script>


            function countChar(val) 

             var limit = 1024;

            if ( val.length > limit )
              $("#comment").val(val.substring(0, limit-1));
              val.length = limit;



        <textarea id="comment" onKeyUp="countChar(this.value)" required></textarea>

        <div id="count"></div>

Use the following to skip using else and also skip getting negative count.

How to modify values of JsonObject / JsonArray directly?

It's actually all in the documentation.
JSONObject and JSONArray can both be used to replace the standard data structure.
To implement a setter simply call a remove(String name) before a put(String name, Object value).

Here's an simple example:

public class BasicDB {

private JSONObject jData = new JSONObject;

public BasicDB(String username, String tagline) {
    try {
        jData.put("username", username);
        jData.put("tagline" , tagline);
    } catch (JSONException e) {
        // TODO Auto-generated catch block

public String getUsername () { 
    String ret = null;
    try {
        ret = jData.getString("username");
    } catch (JSONException e) {
    // TODO Auto-generated catch block
    return ret;

public void setUsername (String username) { 
    try {
        jData.put("username" , username);
    } catch (JSONException e) {
        // TODO Auto-generated catch block

public String getTagline () {
    String ret = null;
    try {
        ret = jData.getString("tagline");
    } catch (JSONException e) {
    // TODO Auto-generated catch block
    return ret;

How do I alter the position of a column in a PostgreSQL database table?

"Alter column position" in the PostgreSQL Wiki says:

PostgreSQL currently defines column order based on the attnum column of the pg_attribute table. The only way to change column order is either by recreating the table, or by adding columns and rotating data until you reach the desired layout.

That's pretty weak, but in their defense, in standard SQL, there is no solution for repositioning a column either. Database brands that support changing the ordinal position of a column are defining an extension to SQL syntax.

One other idea occurs to me: you can define a VIEW that specifies the order of columns how you like it, without changing the physical position of the column in the base table.

flutter corner radius with transparent background

If you wrap your Container with rounded corners inside of a parent with the background color set to Colors.transparent I think that does what you're looking for. If you're using a Scaffold the default background color is white. Change that to Colors.transparent if that achieves what you want.

        new Container(
          height: 300.0,
          color: Colors.transparent,
          child: new Container(
            decoration: new BoxDecoration(
              borderRadius: new BorderRadius.only(
                topLeft: const Radius.circular(40.0),
                topRight: const Radius.circular(40.0),
            child: new Center(
            child: new Text("Hi modal sheet"),

Failed to open/create the internal network Vagrant on Windows10

I found a solution

  1. Open Windows Network Connections
  2. Right click on VirtualBox Host only adapter that created
  3. Choose properties
  4. Check "VirtualBox NDIS6 Bridged Networking driver"
  5. disable and Enable the adapter


How to include Javascript file in Asp.Net page

I assume that you are using MasterPage so within your master page you should have

<head runat="server">
    <asp:ContentPlaceHolder ID="head" runat="server">

And within any of your pages based on that MasterPage add this

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
    <script src="js/yourscript.js" type="text/javascript"></script>

Android Split string

You might also want to consider the Android specific TextUtils.split() method.

The difference between TextUtils.split() and String.split() is documented with TextUtils.split():

String.split() returns [''] when the string to be split is empty. This returns []. This does not remove any empty strings from the result.

I find this a more natural behavior. In essence TextUtils.split() is just a thin wrapper for String.split(), dealing specifically with the empty-string case. The code for the method is actually quite simple.

Why do you create a View in a database?

Views can be a godsend when when doing reporting on legacy databases. In particular, you can use sensical table names instead of cryptic 5 letter names (where 2 of those are a common prefix!), or column names full of abbreviations that I'm sure made sense at the time.