Programs & Examples On #Uitouch

UITouch is a class from UIKit framework in Apple iOS. A UITouch object represents the presence or movement of a finger on the screen for a particular event.

How can I detect the touch event of an UIImageView?

For those of you looking for a Swift 4 solution to this answer, you can use the following to detect a touch event on a UIImageView.

let gestureRecognizer: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(imageViewTapped))
imageView.isUserInteractionEnabled = true

You will then need to define your selector as follows:

@objc func imageViewTapped() {
    // Image has been tapped

How to read data From *.CSV file using javascript?

Actually you can use a light-weight library called any-text.

  • install dependencies
npm i -D any-text
  • use custom command to read files
var reader = require('any-text');
reader.getText(`path-to-file`).then(function (data) {

or use async-await :

var reader = require('any-text');
const chai = require('chai');
const expect = chai.expect;
describe('file reader checks', () => {
  it('check csv file content', async () => {
      await reader.getText(`${process.cwd()}/test/files/dummy.csv`)
    ).to.contains('Lorem ipsum');

Is there a way to catch the back button event in javascript?

Check out history.js. There is a html 5 statechange event and you can listen to it.

Function to Calculate a CRC16 Checksum

There are several details you need to 'match up' with for a particular CRC implementation - even using the same polynomial there can be different results because of minor differences in how data bits are handled, using a particular initial value for the CRC (sometimes it's zero, sometimes 0xffff), and/or inverting the bits of the CRC. For example, sometimes one implementation will work from the low order bits of the data bytes up, while sometimes they'll work from the high order bits down (as yours currently does).

Also, you need to 'push out' the last bits of the CRC after you've run all the data bits through.

Keep in mind that CRC algorithms were designed to be implemented in hardware, so some of how bit ordering is handled may not make so much sense from a software point of view.

If you want to match the CRC16 with polynomial 0x8005 as shown on the CRC calculator page, you need to make the following changes to your CRC function:

  • a) run the data bits through the CRC loop starting from the least significant bit instead of from the most significant bit
  • b) push the last 16 bits of the CRC out of the CRC register after you've finished with the input data
  • c) reverse the CRC bits (I'm guessing this bit is a carry over from hardware implementations)

So, your function might look like:

#define CRC16 0x8005

uint16_t gen_crc16(const uint8_t *data, uint16_t size)
    uint16_t out = 0;
    int bits_read = 0, bit_flag;

    /* Sanity check: */
    if(data == NULL)
        return 0;

    while(size > 0)
        bit_flag = out >> 15;

        /* Get next bit: */
        out <<= 1;
        out |= (*data >> bits_read) & 1; // item a) work from the least significant bits

        /* Increment bit counter: */
        if(bits_read > 7)
            bits_read = 0;

        /* Cycle check: */
            out ^= CRC16;


    // item b) "push out" the last 16 bits
    int i;
    for (i = 0; i < 16; ++i) {
        bit_flag = out >> 15;
        out <<= 1;
            out ^= CRC16;

    // item c) reverse the bits
    uint16_t crc = 0;
    i = 0x8000;
    int j = 0x0001;
    for (; i != 0; i >>=1, j <<= 1) {
        if (i & out) crc |= j;

    return crc;

That function returns 0xbb3d for me when I pass in "123456789".

How can I hide select options with JavaScript? (Cross browser)

Had a crack at it myself and this is what I came up with:


    $.fn.extend({detachOptions: function(o) {
        var s = this;
        return s.each(function(){
            var d ='selectOptions') || [];
            s.find(o).each(function() {
  'selectOptions', d);
    }, attachOptions: function(o) {
        var s = this;
        return s.each(function(){
            var d ='selectOptions') || [];
            for (var i in d) {
                if (d[i].is(o)) {
                    // TODO: remove option from data array


// example

You can see the example at

The option elements are fully removed from the selects and can be re-added again by jQuery selector.

Probably needs a bit of work and testing before it works well enough for all cases, but it's good enough for what I need.

How to clear/delete the contents of a Tkinter Text widget?

I think this:

text.delete("1.0", tkinter.END)

Or if you did from tkinter import *

text.delete("1.0", END)

That should work

Adobe Reader Command Line Reference

Call this after the print job has returned:

oShell.AppActivate "Adobe Reader"
oShell.SendKeys "%FX"

How to get data by SqlDataReader.GetValue by column name

thisReader.GetString(int columnIndex)

How can I get the number of records affected by a stored procedure?

WARNING: @@ROWCOUNT may return bogus data if the table being altered has triggers attached to it!

The @@ROWCOUNT will return the number of records affected by the TRIGGER, not the actual statement!

How to calculate 1st and 3rd quartiles?

Coincidentally, this information is captured with the describe method:


count    5.000000
mean     0.496667
std      0.032059
min      0.450000
25%      0.483333
50%      0.500000
75%      0.516667
max      0.533333
Name: time_diff, dtype: float64

Java: Convert String to TimeStamp

I'm sure the solution is that your oldDateString is something like "2009-10-20". Obviously this does not contain any time data lower than days. If you format this string with your new formatter where should it get the minutes, seconds and milliseconds from?

So the result is absolutely correct: 2009-10-20 00:00:00.000

What you'll need to solve this, is the original timestamp (incl. time data) before your first formatting.

How does a Linux/Unix Bash script know its own PID?

In addition to the example given in the Advanced Bash Scripting Guide referenced by Jefromi, these examples show how pipes create subshells:

$ echo $$ $BASHPID | cat -
11656 31528
$ echo $$ $BASHPID
11656 11656
$ echo $$ | while read line; do echo $line $$ $BASHPID; done
11656 11656 31497
$ while read line; do echo $line $$ $BASHPID; done <<< $$
11656 11656 11656

Returning from a void function

Neither is more correct, so take your pick. The empty return; statement is provided to allow a return in a void function from somewhere other than the end. No other reason I believe.

What's the difference between an element and a node in XML?

An element is a type of node as are attributes, text etc.

How to get JSON data from the URL (REST API) to UI using jQuery or plain JavaScript?

You can use us jquery function getJson :

    $.getJSON('/api/rest/abc', function(data) {

graphing an equation with matplotlib

This is because in line

graph(x**3+2*x-4, range(-10, 11))

x is not defined.

The easiest way is to pass the function you want to plot as a string and use eval to evaluate it as an expression.

So your code with minimal modifications will be

import numpy as np  
import matplotlib.pyplot as plt  
def graph(formula, x_range):  
    x = np.array(x_range)  
    y = eval(formula)
    plt.plot(x, y)

and you can call it as

graph('x**3+2*x-4', range(-10, 11))

How to get local server host and port in Spring Boot?

For Spring 2

val hostName = InetAddress.getLocalHost().hostName

var webServerPort: Int = 0
class ApplicationListenerWebServerInitialized : ApplicationListener<WebServerInitializedEvent> {
    override fun onApplicationEvent(event: WebServerInitializedEvent) {
        webServerPort = event.webServer.port

then you can use also webServerPort from anywhere...

Java: How to resolve java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException

This worked for me, I have an spring boot project that compiles in Java 8 but I don't know why one day my maven started compiling with Java 11, in Ubuntu I used to fix it:

sudo update-java-alternatives  -l

That showed me the availave JDK on my pc:

java-1.11.0-openjdk-amd64      1111       /usr/lib/jvm/java-1.11.0-openjdk-amd64
java-1.8.0-openjdk-amd64       1081       /usr/lib/jvm/java-1.8.0-openjdk-amd64`

So I finally run this command to choose the desired one:

sudo update-java-alternatives  -s java-1.8.0-openjdk-amd64 

And that's it, for more into take a look at How to use the command update alternatives

PHP date() with timezone?

For such task, you should really be using PHP's DateTime class. Please ignore all of the answers advising you to use date() or date_set_time_zone, it's simply bad and outdated.

I'll use pseudocode to demonstrate, so try to adjust the code to suit your needs.

Assuming that variable $tz contains string name of a valid time zone and variable $timestamp contains the timestamp you wish to format according to time zone, the code would look like this:

$tz = 'Europe/London';
$timestamp = time();
$dt = new DateTime("now", new DateTimeZone($tz)); //first argument "must" be a string
$dt->setTimestamp($timestamp); //adjust the object to correct timestamp
echo $dt->format('d.m.Y, H:i:s');

DateTime class is powerful, and to grasp all of its capabilities - you should devote some of your time reading about it at To answer your question fully - yes, you can adjust the time zone parameter dynamically (on each iteration while reading from db, you can create a new DateTimeZone() object).

SQL Server copy all rows from one table into another i.e duplicate table

select * into x_history from your_table_here;
truncate table your_table_here;

XPath to fetch SQL XML value

I think the xpath query you want goes something like this:

/xml/box[@stepId="$stepId"]/components/component[@id="$componentId"]/variables/variable[@nom="Enabled" and @valeur="Yes"]

This should get you the variables that are named "Enabled" with a value of "Yes" for the specified $stepId and $componentId. This is assuming that your xml starts with an tag like you show, and not

If the SQL Server 2005 XPath stuff is pretty straightforward (I've never used it), then the above query should work. Otherwise, someone else may have to help you with that.

@Directive vs @Component in Angular

If you refer the official angular docs

There are three kinds of directives in Angular:

  1. Components—directives with a template.
  2. Structural directives—change the DOM layout by adding and removing DOM elements. e.g *ngIf
  3. Attribute directives—change the appearance or behavior of an element, component, or another directive. e.g [ngClass].

As the Application grows we find difficulty in maintaining all these codes. For reusability purpose, we separate our logic in smart components and dumb components and we use directives (structural or attribute) to make changes in the DOM.

How to add icon inside EditText view in Android ?

use android:drawbleStart propery on EditText

        android:drawableStart="@drawable/my_icon" />

window.onload vs $(document).ready()

window.onload: A normal JavaScript event.

document.ready: A specific jQuery event when the entire HTML has been loaded.

How to recursively find and list the latest modified files in a directory with subdirectories and times

To find all files whose file status was last changed N minutes ago:

find -cmin -N

For example:

find -cmin -5

Input and Output binary streams using JERSEY?

I found the following helpful to me and I wanted to share in case it helps you or someone else. I wanted something like MediaType.PDF_TYPE, which doesn't exist, but this code does the same thing:



In my case I was posting a PDF document to another site:

FormDataMultiPart p = new FormDataMultiPart();
p.bodyPart(new FormDataBodyPart(FormDataContentDisposition
        new File("path/to/document.pdf"),

Then p gets passed as the second parameter to post().

This link was helpful to me in putting this code snippet together:

How to put spacing between floating divs?

I'm late to the party but... I've had a similar situation come up and I discovered padding-right (and bottom, top, left too, of course). From the way I understand its definition, it puts a padding area inside the inner div so there's no need to add a negative margin on the parent as you did with a margin.

padding-right: 10px;

This did the trick for me!

how to use Spring Boot profiles

You can specify properties according profiles in one like here. Then mvn clean spring-boot:run should run it correct. It works for me

How to fix/convert space indentation in Sublime Text?

I actually found it's better for my sanity to have user preferences to be defined like so:

"translate_tabs_to_spaces": true,
"tab_size": 2,
"indent_to_bracket": true,
"detect_indentation": false

The detect_indentation: false is especially important, as it forces Sublime to honor these settings in every file, as opposed to the View -> Indentation settings.

If you want to get fancy, you can also define a keyboard shortcut to automatically re-indent your code (YMMV) by pasting the following in Sublime -> Preferences -> Key Binding - User:

  { "keys": ["ctrl+i"], "command": "reindent" }

and to visualize the whitespace:

"indent_guide_options": ["draw_active"],
"trim_trailing_white_space_on_save": true,
"ensure_newline_at_eof_on_save": true,
"draw_white_space": "all",
"rulers": [120],

SQL Statement with multiple SETs and WHEREs

Best option is multiple updates.

Alternatively you can do the following but is NOT recommended:

UPDATE table
SET ID = CASE WHEN ID = 2555 THEN 111111259 
              WHEN ID = 2724 THEN 111111261
              WHEN ID = 2021 THEN 111111263
              WHEN ID = 2017 THEN 111111264
WHERE ID IN (2555,2724,2021,2017)

Maven: How do I activate a profile from command line?

Just remove activation section, I don't know why -Pdev1 doesn't override default false activation. But if you omit this:

<activation> <activeByDefault>false</activeByDefault> </activation>

then your profile will be activated only after explicit declaration as -Pdev1

Min and max value of input in angular4 application

You can control with a change event if the input is within your range, if it is not in the range you assign 0.

  <input type="number" 
    (change)= "rateInput < 0 ? rateInput = 0 : rateInput; rateInput > 100 ? rateInput = 0 : rateIntput;"
  <md-error>Required field</md-error>

log4j configuration via JVM argument(s)?

Do you have a log4j configuration file ? Just reference it using

-Dlog4j.configuration={path to file}

where {path to file} should be prefixed with file:

Edit: If you are working with log4j2, you need to use

-Dlog4j.configurationFile={path to file}

Taken from answer

How to print third column to last column?

awk '{print ""}{for(i=3;i<=NF;++i)printf $i" "}'

Measuring elapsed time with the Time module

Vadim Shender response is great. You can also use a simpler decorator like below:

import datetime
def calc_timing(original_function):                            
    def new_function(*args,**kwargs):                        
        start =                     
        x = original_function(*args,**kwargs)                
        elapsed =                      
        print("Elapsed Time = {0}".format(elapsed-start))     
        return x                                             
    return new_function()  

def a_func(*variables):
    print("do something big!")

how to inherit Constructor from super class to sub class

Say if you have

public KKSSocket(final KKSApp app, final String name) { = app; = name;

then a sub-class named KKSUDPSocket extending KKSSocket could have:

 * @param app
 * @param path
 * @param remoteAddr
public KKSUDPSocket(KKSApp app, String path, KKSAddress remoteAddr) {
    super(app, path, remoteAddr);


 * @param app
 * @param path
public KKSUDPSocket(KKSApp app, String path) {
    super(app, path);

You simply pass the arguments up the constructor chain, like method calls to super classes, but using super(...) which references the super-class constructor and passes in the given args.

Postman: How to make multiple requests at the same time

Run all Collection in a folder in parallel:

'use strict';

global.Promise = require('bluebird');
const path = require('path');
const newman =  Promise.promisifyAll(require('newman'));
const fs = Promise.promisifyAll(require('fs'));
const environment = 'postman_environment.json';
const FOLDER = path.join(__dirname, 'Collections_Folder');

let files = fs.readdirSync(FOLDER);
files => path.join(FOLDER, file))
console.log(files);, file => {

    return newman.runAsync({
    collection: file, // your collection
    environment: path.join(__dirname, environment), //your env
    reporters: ['cli']

}, {
   concurrency: 2

Passing vector by reference

You don't need to use **arr, you can either use:

void do_something(int el, std::vector<int> *arr){


 void do_something(int el, std::vector<int> &arr){

**arr makes no sense but if you insist using it, do it this way:

void do_something(int el, std::vector<int> **arr){

but again there is no reason to do so...

‘ant’ is not recognized as an internal or external command

even with the environment variables set, I found that ant -version does not work in scripts. Try call ant -version

RS256 vs HS256: What's the difference?

In cryptography there are two types of algorithms used:

Symmetric algorithms

A single key is used to encrypt data. When encrypted with the key, the data can be decrypted using the same key. If, for example, Mary encrypts a message using the key "my-secret" and sends it to John, he will be able to decrypt the message correctly with the same key "my-secret".

Asymmetric algorithms

Two keys are used to encrypt and decrypt messages. While one key(public) is used to encrypt the message, the other key(private) can only be used to decrypt it. So, John can generate both public and private keys, then send only the public key to Mary to encrypt her message. The message can only be decrypted using the private key.

HS256 and RS256 Scenario

These algorithms are NOT used to encrypt/decryt data. Rather they are used to verify the origin or the authenticity of the data. When Mary needs to send an open message to Jhon and he needs to verify that the message is surely from Mary, HS256 or RS256 can be used.

HS256 can create a signature for a given sample of data using a single key. When the message is transmitted along with the signature, the receiving party can use the same key to verify that the signature matches the message.

RS256 uses pair of keys to do the same. A signature can only be generated using the private key. And the public key has to be used to verify the signature. In this scenario, even if Jack finds the public key, he cannot create a spoof message with a signature to impersonate Mary.

Count length of array and return 1 if it only contains one element

declare you array as:

$car = array("bmw")


now with powershell syntax:)

$car = [array]"bmw"

Read all files in a folder and apply a function to each data frame

usually i don't use for loop in R, but here is my solution using for loops and two packages : plyr and dostats

plyr is on cran and you can download dostats on (may be using install_github from Hadley devtools package)

Assuming that i have your first two data.frame (Df.1 and Df.2) in csv files, you can do something like this.


files <- list.files(pattern = ".csv")

for (i in seq_along(files)) {

    assign(paste("Df", i, sep = "."), read.csv(files[i]))

    assign(paste(paste("Df", i, sep = ""), "summary", sep = "."), 
           ldply(get(paste("Df", i, sep = ".")), dostats, sum, min, mean, median, max))


Here is the output

R> Df1.summary
  .id sum min   mean median max
1   A  34   4 5.6667    5.5   8
2   B  22   1 3.6667    3.0   9
R> Df2.summary
  .id sum min   mean median max
1   A  21   1 3.5000    3.5   6
2   B  16   1 2.6667    2.5   5

File inside jar is not visible for spring

I had the same issue, ended up using the much more convenient Guava Resources:


How do I perform HTML decoding/encoding using Python/Django?

If anyone is looking for a simple way to do this via the django templates, you can always use filters like this:

{{ node.description|safe }}

I had some data coming from a vendor and everything I posted had html tags actually written on the rendered page as if you were looking at the source.

Detecting the onload event of a window opened with

The core problem seems to be you are opening a window to show a page whose content is already cached in the browser. Therefore no loading happens and therefore no load-event happens.

One possibility could be to use the 'pageshow' -event instead, as described in:

git: fatal: Could not read from remote repository

I had this problem using gitbash on windows 10. I tried several things to solve this problem, the major ones being these:

  1. Recreated my ssh keys and updated to bitbucket. Didn't help
  2. Turned on debugging using this and found out that I was getting "shell request failed on channel 0" as asked here
  3. Rebooted my windows PC

None of the above helped. I ended up re-installing Git for windows This took only a few minutes as compared to other things I did and it solved the problem!

What is FCM token in Firebase?

What is it exactly?

An FCM Token, or much commonly known as a registrationToken like in . As described in the GCM FCM docs:

An ID issued by the GCM connection servers to the client app that allows it to receive messages. Note that registration tokens must be kept secret.

How can I get that token?

Update: The token can still be retrieved by calling getToken(), however, as per FCM's latest version, the FirebaseInstanceIdService.onTokenRefresh() has been replaced with FirebaseMessagingService.onNewToken() -- which in my experience functions the same way as onTokenRefresh() did.

Old answer:

As per the FCM docs:

On initial startup of your app, the FCM SDK generates a registration token for the client app instance. If you want to target single devices or create device groups, you'll need to access this token.

You can access the token's value by extending FirebaseInstanceIdService. Make sure you have added the service to your manifest, then call getToken in the context of onTokenRefresh, and log the value as shown:

public void onTokenRefresh() {
    // Get updated InstanceID token.
    String refreshedToken = FirebaseInstanceId.getInstance().getToken();
    Log.d(TAG, "Refreshed token: " + refreshedToken);

    // TODO: Implement this method to send any registration to your app's servers.

The onTokenRefreshcallback fires whenever a new token is generated, so calling getToken in its context ensures that you are accessing a current, available registration token. FirebaseInstanceID.getToken() returns null if the token has not yet been generated.

After you've obtained the token, you can send it to your app server and store it using your preferred method. See the Instance ID API reference for full detail on the API.

AngularJS access parent scope from child controller

When you are using as syntax, like ParentController as parentCtrl, to define a controller then to access parent scope variable in child controller use following :

var id = $;

Where parentCtrl is name of parent controller using as syntax and id is a variable defined in same controller.

Pull new updates from original GitHub repository into forked GitHub repository


git remote add upstream ORIGINAL_REPOSITORY_URL

This will set your upstream to the repository you forked from. Then do this:

git fetch upstream      

This will fetch all the branches including master from the original repository.

Merge this data in your local master branch:

git merge upstream/master

Push the changes to your forked repository i.e. to origin:

git push origin master

Voila! You are done with the syncing the original repository.

FPDF utf-8 encoding (HOW-TO)

Don't use UTF-8 encoding. Standard FPDF fonts use ISO-8859-1 or Windows-1252. It is possible to perform a conversion to ISO-8859-1 with utf8_decode(): $str = utf8_decode($str); But some characters such as Euro won't be translated correctly. If the iconv extension is available, the right way to do it is the following: $str = iconv('UTF-8', 'windows-1252', $str);

How to enter a series of numbers automatically in Excel

Use formula =row(b2)-x, where x will adjust the entries so that the first S/No is marked as 1 and will increment with the rows.


When you are using a self signed cert urllib3 version 1.25.3 refuses to ignore the SSL cert

To fix remove urllib3-1.25.3 and install urllib3-1.24.3

pip3 uninstall urllib3

pip3 install urllib3==1.24.3

Tested on Linux MacOS and Window$

How to create a SQL Server function to "join" multiple rows from a subquery into a single delimited field?

With the other answers, the person reading the answer must be aware of the vehicle table and create the vehicle table and data to test a solution.

Below is an example that uses SQL Server "Information_Schema.Columns" table. By using this solution, no tables need to be created or data added. This example creates a comma separated list of column names for all tables in the database.

        SELECT ',' + Column_Name
        FROM INFORMATION_SCHEMA.Columns Columns
        WHERE Tables.Table_Name = Columns.Table_Name
        ORDER BY Column_Name
        FOR XML PATH ('')), 1, 1, ''

What does "javax.naming.NoInitialContextException" mean?

It means that there is no initial context :)

But seriously folks, JNDI (javax.naming) is all about looking up objects or resources from some directory or provider. To look something up, you need somewhere to look (this is the InitialContext). NoInitialContextException means "I want to find the telephone number for John Smith, but I have no phonebook to look in".

An InitialContext can be created in any number of ways. It can be done manually, for instance creating a connection to an LDAP server. It can also be set up by an application server inside which you run your application. In this case, the container (application server) already provides you with a "phonebook", through which you can look up anything the application server makes available. This is often configurable and a common way of moving this type of configuration from the application implementation to the container, where it can be shared across all applications in the server.

UPDATE: from the code snippet you post it looks like you are trying to run code stand-alone that is meant to be run in an application server. In this case, the code attempting to get a connection to a database from the "phonebook". This is one of the resources that is often configured in the application server container. So, rather than having to manage configuration and connections to the database in your code, you can configure it in your application server and simple ask for a connection (using JNDI) in your code.

Using Google Text-To-Speech in Javascript

Another option now may be HTML5 text to speech, which is in Chrome 33+ and many others.

Here is a sample:

var msg = new SpeechSynthesisUtterance('Hello World');

With this, perhaps you do not need to use a web service at all.

How can I get href links from HTML using Python?

Try with Beautifulsoup:

from BeautifulSoup import BeautifulSoup
import urllib2
import re

html_page = urllib2.urlopen("")
soup = BeautifulSoup(html_page)
for link in soup.findAll('a'):
    print link.get('href')

In case you just want links starting with http://, you should use:

soup.findAll('a', attrs={'href': re.compile("^http://")})

In Python 3 with BS4 it should be:

from bs4 import BeautifulSoup
import urllib.request

html_page = urllib.request.urlopen("")
soup = BeautifulSoup(html_page, "html.parser")
for link in soup.findAll('a'):

Change Color of Fonts in DIV (CSS)

Your first CSS selector—social.h2—is looking for the "social" element in the "h2", class, e.g.:

<social class="h2">

Class selectors are proceeded with a dot (.). Also, use a space () to indicate that one element is inside of another. To find an <h2> descendant of an element in the social class, try something like:

.social h2 {
  color: pink;
  font-size: 14px;

To get a better understanding of CSS selectors and how they are used to reference your HTML, I suggest going through the interactive HTML and CSS tutorials from CodeAcademy. I hope that this helps point you in the right direction.

How to create a circular ImageView in Android?

I too needed a rounded ImageView, I used the below code, you can modify it accordingly:

import android.content.Context;
import android.util.AttributeSet;
import android.widget.ImageView;

public class RoundedImageView extends ImageView {

    public RoundedImageView(Context context) {

    public RoundedImageView(Context context, AttributeSet attrs) {
        super(context, attrs);

    public RoundedImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

    protected void onDraw(Canvas canvas) {

        Drawable drawable = getDrawable();

        if (drawable == null) {

        if (getWidth() == 0 || getHeight() == 0) {
        Bitmap b = ((BitmapDrawable) drawable).getBitmap();
        Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);

        int w = getWidth();
        int h = getHeight();

        Bitmap roundBitmap = getCroppedBitmap(bitmap, w);
        canvas.drawBitmap(roundBitmap, 0, 0, null);


    public static Bitmap getCroppedBitmap(Bitmap bmp, int radius) {
        Bitmap sbmp;

        if (bmp.getWidth() != radius || bmp.getHeight() != radius) {
            float smallest = Math.min(bmp.getWidth(), bmp.getHeight());
            float factor = smallest / radius;
            sbmp = Bitmap.createScaledBitmap(bmp,
                    (int) (bmp.getWidth() / factor),
                    (int) (bmp.getHeight() / factor), false);
        } else {
            sbmp = bmp;

        Bitmap output = Bitmap.createBitmap(radius, radius, Config.ARGB_8888);
        Canvas canvas = new Canvas(output);

        final String color = "#BAB399";
        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, radius, radius);

        canvas.drawARGB(0, 0, 0, 0);
        canvas.drawCircle(radius / 2 + 0.7f, radius / 2 + 0.7f,
                radius / 2 + 0.1f, paint);
        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        canvas.drawBitmap(sbmp, rect, rect, paint);

        return output;


How to capture a backspace on the onkeydown event

Nowadays, code to do this should look something like:

document.getElementById('foo').addEventListener('keydown', function (event) {
    if (event.keyCode == 8) {
        console.log('BACKSPACE was pressed');

        // Call event.preventDefault() to stop the character before the cursor
        // from being deleted. Remove this line if you don't want to do that.
    if (event.keyCode == 46) {
        console.log('DELETE was pressed');

        // Call event.preventDefault() to stop the character after the cursor
        // from being deleted. Remove this line if you don't want to do that.

although in the future, once they are broadly supported in browsers, you may want to use the .key or .code attributes of the KeyboardEvent instead of the deprecated .keyCode.

Details worth knowing:

  • Calling event.preventDefault() in the handler of a keydown event will prevent the default effects of the keypress. When pressing a character, this stops it from being typed into the active text field. When pressing backspace or delete in a text field, it prevents a character from being deleted. When pressing backspace without an active text field, in a browser like Chrome where backspace takes you back to the previous page, it prevents that behaviour (as long as you catch the event by adding your event listener to document instead of a text field).

  • Documentation on how the value of the keyCode attribute is determined can be found in section B.2.1 How to determine keyCode for keydown and keyup events in the W3's UI Events Specification. In particular, the codes for Backspace and Delete are listed in B.2.3 Fixed virtual key codes.

  • There is an effort underway to deprecate the .keyCode attribute in favour of .key and .code. The W3 describe the .keyCode property as "legacy", and MDN as "deprecated".

    One benefit of the change to .key and .code is having more powerful and programmer-friendly handling of non-ASCII keys - see the specification that lists all the possible key values, which are human-readable strings like "Backspace" and "Delete" and include values for everything from modifier keys specific to Japanese keyboards to obscure media keys. Another, which is highly relevant to this question, is distinguishing between the meaning of a modified keypress and the physical key that was pressed.

    On small Mac keyboards, there is no Delete key, only a Backspace key. However, pressing Fn+Backspace is equivalent to pressing Delete on a normal keyboard - that is, it deletes the character after the text cursor instead of the one before it. Depending upon your use case, in code you might want to handle a press of Backspace with Fn held down as either Backspace or Delete. That's why the new key model lets you choose.

    The .key attribute gives you the meaning of the keypress, so Fn+Backspace will yield the string "Delete". The .code attribute gives you the physical key, so Fn+Backspace will still yield the string "Backspace".

    Unfortunately, as of writing this answer, they're only supported in 18% of browsers, so if you need broad compatibility you're stuck with the "legacy" .keyCode attribute for the time being. But if you're a reader from the future, or if you're targeting a specific platform and know it supports the new interface, then you could write code that looked something like this:

    document.getElementById('foo').addEventListener('keydown', function (event) {
        if (event.code == 'Delete') {
            console.log('The physical key pressed was the DELETE key');
        if (event.code == 'Backspace') {
            console.log('The physical key pressed was the BACKSPACE key');
        if (event.key == 'Delete') {
            console.log('The keypress meant the same as pressing DELETE');
            // This can happen for one of two reasons:
            // 1. The user pressed the DELETE key
            // 2. The user pressed FN+BACKSPACE on a small Mac keyboard where
            //    FN+BACKSPACE deletes the character in front of the text cursor,
            //    instead of the one behind it.
        if (event.key == 'Backspace') {
            console.log('The keypress meant the same as pressing BACKSPACE');

Eclipse Error: "Failed to connect to remote VM"

I've encountered like this in Hybris.

  1. Check your port in Resource Monitor > Network. Check if other service is using your port.

1.2 If yes, then you need to change your properties in

1.3 Change your address, any available address. In my case, I changed from 8000 to 8080. then save.

java -Xdebug -Xrunjdwp:server=y,transport=dt_socket,address=8080,suspend=n yourServer
  1. In your console, rebuild your ant using command 'ant all'

  2. Then debug again, using the command 'hybrisserver.bat debug'

format a number with commas and decimals in C# ( MVC3)

Maybe you simply want the standard format string "N", as in


It will use thousand separators, and a fixed number of fractional decimals. The symbol for thousands separators and the symbol for the decimal point depend on the format provider (typically CultureInfo) you use, as does the number of decimals (which will normally by 2, as you require).

If the format provider specifies a different number of decimals, and if you don't want to change the format provider, you can give the number of decimals after the N, as in .ToString("N2").

Edit: The sizes of the groups between the commas are governed by the


array, given that you don't specify a special format provider.

Managing SSH keys within Jenkins for Git

It looks like the host which jenkins tries to connect to is not listed under the Jenkins user's $HOME/.ssh/known_hosts. Jenkins runs on most distros as the user jenkins and hence has its own .ssh directory to store the list of public keys and known_hosts.

The easiest solution I can think of to fix this problem is:

# Login as the jenkins user and specify shell explicity,
# since the default shell is /bin/false for most
# jenkins installations.
sudo su jenkins -s /bin/bash

# git clone YOUR_GITHUB_URL

# Allow adding the SSH host key to your known_hosts

# Exit from su

Deleting all files in a directory with Python

On Linux and macOS you can run simple command to the shell:'rm /tmp/*.bak', shell=True)

Appending an id to a list if not already present in a string

I agree with other answers that you are doing something weird here. You have a list containing a string with multiple entries that are themselves integers that you are comparing to an integer id.

This is almost surely not what you should be doing. You probably should be taking input and converting it to integers before storing in your list. You could do that with:

input = '350882 348521 350166\r\n'
list.append([int(x) for x in input.split()])

Then your test will pass. If you really are sure you don't want to do what you're currently doing, the following should do what you want, which is to not add the new id that already exists:

list = ['350882 348521 350166\r\n']
id = 348521
if id not in [int(y) for x in list for y in x.split()]:
print list

How can I disable editing cells in a WPF Datagrid?

I see users in comments wondering how to disable cell editing while allowing row deletion : I managed to do this by setting all columns individually to read only, instead of the DataGrid itself.

<DataGrid IsReadOnly="False">
        <DataGridTextColumn IsReadOnly="True"/>
        <DataGridTextColumn IsReadOnly="True"/>

What is the correct wget command syntax for HTTPS with username and password?

By specifying the option --user and --ask-password wget will ask for the credentials. Below is an example. Change the username and download link to your needs.

wget --user=username --ask-password

LINQ Contains Case Insensitive

Honestly, this doesn't need to be difficult. It may seem that on the onset, but it's not. Here's a simple linq query in C# that does exactly as requested.

In my example, I'm working against a list of persons that have one property called FirstName.

var results = ClientsRepository().Where(c => c.FirstName.ToLower().Contains(searchText.ToLower())).ToList();

This will search the database on lower case search but return full case results.

Characters allowed in GET parameter

From RFC 1738 on which characters are allowed in URLs:

Only alphanumerics, the special characters "$-_.+!*'(),", and reserved characters used for their reserved purposes may be used unencoded within a URL.

The reserved characters are ";", "/", "?", ":", "@", "=" and "&", which means you would need to URL encode them if you wish to use them.

Import Excel Data into PostgreSQL 9.3

You can handle loading the excel file content by writing Java code using Apache POI library ( The library is developed for working with MS office application data including Excel.

I have recently created the application based on the technology that will help you to load Excel files to the Postgres database. The application is available under The application is tested only for Windows, but should work for Linux as well.

The application automatically creates necessary tables with the same columns as in the Excel files and populate the tables with content. You can export several files in parallel. You can skip the step to convert the files into the CSV format. The application handles the xls and xlsx formats.

Overall application stages are :

  1. Load the excel file content. Here is the code depending on file extension:


fileExtension = FilenameUtils.getExtension(inputSheetFile.getName());
    if (fileExtension.equalsIgnoreCase("xlsx")) {
        workbook = createWorkbook(openOPCPackage(inputSheetFile));
    } else {
        workbook =     

sheet = workbook.getSheetAt(0);


  1. Establish Postgres JDBC connection
  2. Create a Postgres table
  3. Iterate over the sheet and inset rows into the table. Here is a piece of Java code :


Iterator<Row> rowIterator = InitInputFilesImpl.sheet.rowIterator();

//skip a header
if (rowIterator.hasNext()) {;
while (rowIterator.hasNext()) {
    Row row = (Row);
    // inserting rows


Here you can find all Java code for the application created for exporting excel to Postgres (

HTTP redirect: 301 (permanent) vs. 302 (temporary)

The main issue with 301 is browser will cache the redirection even if you disabled the redirection from the server level.

Its always better to use 302 if you are enabling the redirection for a short maintenance window.

HTML5 LocalStorage: Checking if a key exists

This method worked for me:

if ("username" in localStorage) {
} else {

++i or i++ in for loops ??

when you use postfix it instantiates on more object in memory. Some people say that it is better to use suffix operator in for loop

How to pass variable from jade template file to a script file?

If you're like me and you use this method of passing variables a lot, here's a write-less-code solution.

In your node.js route, pass the variables in an object called window, like this:

router.get('/', function (req, res, next) {
    res.render('index', {
        window: {
            instance: instance

Then in your pug/jade layout file (just before the block content), you get them out like this:

if window
    each object, key in window
            window.!{key} = !{JSON.stringify(object)};

As my layout.pug file gets loaded with each pug file, I don't need to 'import' my variables over and over.

This way all variables/objects passed to window 'magically' end up in the real window object of your browser where you can use them in Reactjs, Angular, ... or vanilla javascript.

How to select a range of the second row to the last row

Try this:

Dim Lastrow As Integer
Lastrow = ActiveSheet.Cells(Rows.Count, 1).End(xlUp).Row

Range("A2:L" & Lastrow).Select

Let's pretend that the value of Lastrow is 50. When you use the following:

Range("A2:L2" & Lastrow).Select

Then it is selecting a range from A2 to L250.

How can I convert an Integer to localized month name in Java?

Using SimpleDateFormat.

import java.text.SimpleDateFormat;

public String formatMonth(String month) {
    SimpleDateFormat monthParse = new SimpleDateFormat("MM");
    SimpleDateFormat monthDisplay = new SimpleDateFormat("MMMM");
    return monthDisplay.format(monthParse.parse(month));


Result: February

Bash Shell Script - Check for a flag and grab its value

Use $# to grab the number of arguments, if it is unequal to 2 there are not enough arguments provided:

if [ $# -ne 2 ]; then

Next, check if $1 equals -t, otherwise an unknown flag was used:

if [ "$1" != "-t" ]; then

Finally store $2 in FLAG:


Note: usage() is some function showing the syntax. For example:

function usage {
   cat << EOF
Usage: -t <application>

Performs some activity
   exit 1

How to set limits for axes in ggplot2 R plots?

Quick note: if you're also using coord_flip() to flip the x and the y axis, you won't be able to set range limits using coord_cartesian() because those two functions are exclusive (see here).

Fortunately, this is an easy fix; set your limits within coord_flip() like so:

p + coord_flip(ylim = c(3,5), xlim = c(100, 400))

This just alters the visible range (i.e. doesn't remove data points).

Why does sudo change the PATH?

Looks like this bug has been around for quite a while! Here are some bug references you may find helpful (and may want to subscribe to / vote up, hint, hint...):

Debian bug #85123 ("sudo: SECURE_PATH still can't be overridden") (from 2001!)

It seems that Bug#20996 is still present in this version of sudo. The changelog says that it can be overridden at runtime but I haven't yet discovered how.

They mention putting something like this in your sudoers file:

Defaults secure_path="/bin:/usr/bin:/usr/local/bin"

but when I do that in Ubuntu 8.10 at least, it gives me this error:

visudo: unknown defaults entry `secure_path' referenced near line 10

Ubuntu bug #50797 ("sudo built with --with-secure-path is problematic")

Worse still, as far as I can tell, it is impossible to respecify secure_path in the sudoers file. So if, for example, you want to offer your users easy access to something under /opt, you must recompile sudo.

Yes. There needs to be a way to override this "feature" without having to recompile. Nothing worse then security bigots telling you what's best for your environment and then not giving you a way to turn it off.

This is really annoying. It might be wise to keep current behavior by default for security reasons, but there should be a way of overriding it other than recompiling from source code! Many people ARE in need of PATH inheritance. I wonder why no maintainers look into it, which seems easy to come up with an acceptable solution.

I worked around it like this:

mv /usr/bin/sudo /usr/bin/sudo.orig

then create a file /usr/bin/sudo containing the following:

/usr/bin/sudo.orig env PATH=$PATH "$@"

then your regular sudo works just like the non secure-path sudo

Ubuntu bug #192651 ("sudo path is always reset")

Given that a duplicate of this bug was originally filed in July 2006, I'm not clear how long an ineffectual env_keep has been in operation. Whatever the merits of forcing users to employ tricks such as that listed above, surely the man pages for sudo and sudoers should reflect the fact that options to modify the PATH are effectively redundant.

Modifying documentation to reflect actual execution is non destabilising and very helpful.

Ubuntu bug #226595 ("impossible to retain/specify PATH")

I need to be able to run sudo with additional non-std binary folders in the PATH. Having already added my requirements to /etc/environment I was surprised when I got errors about missing commands when running them under sudo.....

I tried the following to fix this without sucess:

  1. Using the "sudo -E" option - did not work. My existing PATH was still reset by sudo

  2. Changing "Defaults env_reset" to "Defaults !env_reset" in /etc/sudoers -- also did not work (even when combined with sudo -E)

  3. Uncommenting env_reset (e.g. "#Defaults env_reset") in /etc/sudoers -- also did not work.

  4. Adding 'Defaults env_keep += "PATH"' to /etc/sudoers -- also did not work.

Clearly - despite the man documentation - sudo is completely hardcoded regarding PATH and does not allow any flexibility regarding retaining the users PATH. Very annoying as I can't run non-default software under root permissions using sudo.

How can I extract a good quality JPEG image from a video file with ffmpeg?

Output the images in a lossless format such as PNG:

ffmpeg.exe -i 10fps.h264 -r 10 -f image2 10fps.h264_%03d.png

Edit/Update: Not quite sure why I originally gave a strange filename example (with a possibly made-up extension).

I have since found that -vsync 0 is simpler than -r 10 because it avoids needing to know the frame rate.

This is something like what I currently use:

mkdir stills
ffmpeg -i my-film.mp4 -vsync 0 -f image2 stills/my-film-%06d.png

To extract only the key frames (which are likely to be of higher quality post-edit):

ffmpeg -skip_frame nokey -i my-film.mp4 -vsync 0 -f image2 stills/my-film-%06d.png

Then use another program (where you can more precisely specify quality, subsampling and DCT method – e.g. GIMP) to convert the PNGs you want to JPEG.

It is possible to obtain slightly sharper images in JPEG format this way than is possible with -qmin 1 -q:v 1 and outputting as JPEG directly from ffmpeg.

bootstrap responsive table content wrapping

The UberNeo response is Ok and i like it because you do not have to modify anything else except the TD. The only point is that you also have to add "white-space:normal" to the style in order to maintain the responsive characteristics of the table, if not, at certain resolutions the wrap is not made and the scroll of the table does not appear.

style="word-wrap: break-word;min-width: 160px;max-width: 160px;white-space:normal;"

Get current date, given a timezone in PHP?

If you have access to PHP 5.3, the intl extension is very nice for doing things like this.

Here's an example from the manual:

$fmt = new IntlDateFormatter( "en_US" ,IntlDateFormatter::FULL, IntlDateFormatter::FULL,
    'America/Los_Angeles',IntlDateFormatter::GREGORIAN  );
$fmt->format(0); //0 for current time/date

In your case, you can do:

$fmt = new IntlDateFormatter( "en_US" ,IntlDateFormatter::FULL, IntlDateFormatter::FULL,
 $fmt->format($datetime); //where $datetime may be a DateTime object, an integer representing a Unix timestamp value (seconds since epoch, UTC) or an array in the format output by localtime(). 

As you can set a Timezone such as America/New_York, this is much better than using a GMT or UTC offset, as this takes into account the day light savings periods as well.

Finaly, as the intl extension uses ICU data, which contains a lot of very useful features when it comes to creating your own date/time formats.

Create or write/append in text file

You can do it the OO way, just an alternative and flexible:

class Logger {


    public function __construct($filename) {
        $this->file = $filename;

    public function setTimestamp($format) {
        $this->timestamp = date($format)." &raquo; ";

    public function putLog($insert) {
        if (isset($this->timestamp)) {
            file_put_contents($this->file, $this->timestamp.$insert."<br>", FILE_APPEND);
        } else {
            trigger_error("Timestamp not set", E_USER_ERROR);

    public function getLog() {
        $content = @file_get_contents($this->file);
        return $content;


Then use it like this .. let's say you have user_name stored in a session (semi pseudo code):

$log = new Logger("log.txt");
$log->setTimestamp("D M d 'y h.i A");

if (user logs in) {
    $log->putLog("Successful Login: ".$_SESSION["user_name"]);
if (user logs out) {
    $log->putLog("Logout: ".$_SESSION["user_name"]);

Check your log with this:


Result is like:

Sun Jul 02 '17 05.45 PM » Successful Login: JohnDoe
Sun Jul 02 '17 05.46 PM » Logout: JohnDoe

Pass element ID to Javascript function

In jsFiddle by default the code you type into the script block is wrapped in a function executed on window.onload:

<script type='text/javascript'>//<![CDATA[ 
    window.onload = function () {
        function myFunc(id){

Because of this, your function myFunc is not in the global scope so is not available to your html buttons. By changing the option to No-wrap in <head> as Sergio suggests your code isn't wrapped:

<script type='text/javascript'>//<![CDATA[ 
    function myFunc(id){

and so the function is in the global scope and available to your html buttons.

Package doesn't exist error in intelliJ

I tried compile a java 8 project with JDK 12 and has the same issue. None of previous answer solved my problem.

I changed o Shortel Command Line to "JAR Manifest" and worked like a charm.


cancelling a handler.postdelayed process

It worked for me when I called CancelCallBacks(this) inside the post delayed runnable by handing it via a boolean

Runnable runnable = new Runnable(){
    public void run() {
        Log.e("HANDLER", "run: Outside Runnable");
        if (IsRecording) {
            Log.e("HANDLER", "run: Runnable");
            handler.postDelayed(this, 2000);

Statically rotate font-awesome icons

New Font-Awesome v5 has Power Transforms

You can rotate any icon by adding attribute data-fa-transform to icon

<i class="fas fa-magic" data-fa-transform="rotate-45"></i>

Here is a fiddle

For more information, check this out : Font-Awesome5 Power Tranforms

Mounting multiple volumes on a docker container?

Pass multiple -v arguments.

For instance:

docker -v /on/my/host/1:/on/the/container/1 \
       -v /on/my/host/2:/on/the/container/2 \

Find number of decimal places in decimal value regardless of culture

Most people here seem to be unaware that decimal considers trailing zeroes as significant for storage and printing.

So 0.1m, 0.10m and 0.100m may compare as equal, they are stored differently (as value/scale 1/1, 10/2 and 100/3, respectively), and will be printed as 0.1, 0.10 and 0.100, respectively, by ToString().

As such, the solutions that report "too high a precision" are actually reporting the correct precision, on decimal's terms.

In addition, math-based solutions (like multiplying by powers of 10) will likely be very slow (decimal is ~40x slower than double for arithmetic, and you don't want to mix in floating-point either because that's likely to introduce imprecision). Similarly, casting to int or long as a means of truncating is error-prone (decimal has a much greater range than either of those - it's based around a 96-bit integer).

While not elegant as such, the following will likely be one of the fastest way to get the precision (when defined as "decimal places excluding trailing zeroes"):

public static int PrecisionOf(decimal d) {
  var text = d.ToString(System.Globalization.CultureInfo.InvariantCulture).TrimEnd('0');
  var decpoint = text.IndexOf('.');
  if (decpoint < 0)
    return 0;
  return text.Length - decpoint - 1;

The invariant culture guarantees a '.' as decimal point, trailing zeroes are trimmed, and then it's just a matter of seeing of how many positions remain after the decimal point (if there even is one).

Edit: changed return type to int

Listing information about all database files in SQL Server

If you rename your Database, MS SQL Server does not rename the underlying files.

Following query gives you the current name of the database and the Logical file name (which might be the original name of the Database when it was created) and also corresponding physical file names.

Note: Un-comment the last line to see only the actual data files

select  db.database_id, "Database Name", "Logical File Name",
from    sys.master_files files 
        join sys.databases db on db.database_id = files.database_id 
--                           and files.type_desc = 'ROWS'


how to set the query timeout from SQL connection string

See:- ConnectionStrings content on this subject. There is no default command timeout property.

How to set "style=display:none;" using jQuery's attr method?

You can use the jquery attr() method to achieve the setting of teh attribute and the method removeAttr() to delete the attribute for your element msform As seen in the code

$('#msform').attr('style', 'display:none;');


What's the meaning of exception code "EXC_I386_GPFLT"?

I got this error while doing this:

 NSMutableDictionary *aDictionary=[[NSMutableDictionary alloc] initWithObjectsAndKeys:<#(nonnull id), ...#>, nil]; //with 17 objects and keys

It went away when I reverted to:

NSMutableDictionary *aDictionary=[[NSMutableDictionary alloc] init];
[aDictionary setObject:object1 forKey:@"Key1"]; //17 times

You must add a reference to assembly 'netstandard, Version=

We started getting this error on the production server after deploying the application migrated from 4.6.1 to 4.7.2.

We noticed that the .NET framework 4.7.2 was not installed there. In order to solve this issue we did the following steps:

  1. Installed the .NET Framework 4.7.2 from:

  2. Restarted the machine

  3. Confirmed the .NET Framework version with the help of How do I find the .NET version?

Running the application again with the .Net Framework 4.7.2 version installed on the machine fixed the issue.

Cannot download Docker images behind a proxy

This doesn't exactly answer the question, but might help, especially if you don't want to deal with service files.

In case you are the one is hosting the image, one way is to convert the image as a tar archive instead, using something like the following at the server.

docker save <image-name> --output <archive-name>.tar

Simply download the archive and turn it back into an image.

docker load <archive-name>.tar

Better way to generate array of all letters in the alphabet

I think that this ends up a little cleaner, you don't have to deal with the subtraction and indexing:

char[] alphabet = "abcdefghijklmnopqrstuvwxyz".toCharArray();

"A namespace cannot directly contain members such as fields or methods"

The snippet you're showing doesn't seem to be directly responsible for the error.

This is how you can CAUSE the error:

namespace MyNameSpace

   class MyClass

If you don't immediately see what is "outside" the class, this may be due to misplaced or extra closing bracket(s) }.

Insert line break in wrapped cell via code

You could also use vbCrLf which corresponds to Chr(13) & Chr(10).

How to hide .php extension in .htaccess

1) Are you sure mod_rewrite module is enabled? Check phpinfo()

2) Your above rule assumes the URL starts with "folder". Is this correct? Did you acutally want to have folder in the URL? This would match a URL like:

/folder/thing -> /folder/thing.php

If you actually want

/thing -> /folder/thing.php

You need to drop the folder from the match expression.

I usually use this to route request to page without php (but yours should work which leads me to think that mod_rewrite may not be enabled):

RewriteRule ^([^/\.]+)/?$ $1.php  [L,QSA]

3) Assuming you are declaring your rules in an .htaccess file, does your installation allow for setting Options (AllowOverride) overrides in .htaccess files? Some shared hosts do not.

When the server finds an .htaccess file (as specified by AccessFileName) it needs to know which directives declared in that file can override earlier access information.

how to convert date to a format `mm/dd/yyyy`

Use CONVERT with the Value specifier of 101, whilst casting your data to date:


Access index of the parent ng-repeat from child ng-repeat

You can also get control of grand parent index by the following code


Format SQL in SQL Server Management Studio

Late answer, but hopefully worthwhile: The Poor Man's T-SQL Formatter is an open-source (free) T-SQL formatter with complete T-SQL batch/script support (any DDL, any DML), SSMS Plugin, command-line bulk formatter, and other options.

It's available for immediate/online use at, and just today graduated to "version 1.0" (it was in beta version for a few months), having just acquired support for MERGE statements, OUTPUT clauses, and other finicky stuff.

The SSMS Add-in allows you to set your own hotkey (default is Ctrl-K, Ctrl-F, to match Visual Studio), and formats the entire script or just the code you have selected/highlighted, if any. Output formatting is customizable.

In SSMS 2008 it combines nicely with the built-in intelli-sense, effectively providing more-or-less the same base functionality as Red Gate's SQL Prompt (SQL Prompt does, of course, have extra stuff, like snippets, quick object scripting, etc).

Feedback/feature requests are more than welcome, please give it a whirl if you get the chance!

Disclosure: This is probably obvious already but I wrote this library/tool/site, so this answer is also shameless self-promotion :)

Convert a string into an int

How about

[@"7" intValue];

Additionally if you want an NSNumber you could do

NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
[numberFormatter numberFromString:@"7"];

How to remove item from a python list in a loop?

You can't remove items from a list while iterating over it. It's much easier to build a new list based on the old one:

y = [s for s in x if len(s) == 2]

Starting a shell in the Docker Alpine container

Nowadays, Alpine images will boot directly into /bin/sh by default, without having to specify a shell to execute:

$ sudo docker run -it --rm alpine  
/ # echo $0  

This is since the alpine image Dockerfiles now contain a CMD command, that specifies the shell to execute when the container starts: CMD ["/bin/sh"].

In older Alpine image versions (pre-2017), the CMD command was not used, since Docker used to create an additional layer for CMD which caused the image size to increase. This is something that the Alpine image developers wanted to avoid. In recent Docker versions (1.10+), CMD no longer occupies a layer, and so it was added to alpine images. Therefore, as long as CMD is not overridden, recent Alpine images will boot into /bin/sh.

For reference, see the following commit to the official Alpine Dockerfiles by Glider Labs:

How do you implement a Stack and a Queue in JavaScript?

Construct a Queue using two Stacks.

O(1) for both enqueue and dequeue operations.

class Queue {
  constructor() {
    this.s1 = []; // in
    this.s2 = []; // out

  enqueue(val) {

  dequeue() {
    if (this.s2.length === 0) {

    return this.s2.pop(); // return undefined if empty

  _move() {
    while (this.s1.length) {

How to export data to CSV in PowerShell?

simply use the Out-File cmd but DON'T forget to give an encoding type: -Encoding UTF8

so use it so:

$log | Out-File -Append C:\as\whatever.csv -Encoding UTF8

-Append is required if you want to write in the file more then once.

Difference between ApiController and Controller in ASP.NET MVC

Every method in Web API will return data (JSON) without serialization.

However, in order to return JSON Data in MVC controllers, we will set the returned Action Result type to JsonResult and call the Json method on our object to ensure it is packaged in JSON.

How to print all information from an HTTP request to the screen, in PHP

file_get_contents('php://input') will not always work.

I have a request with in the headers "content-length=735" and "php://input" is empty string. So depends on how good/valid the HTTP request is.

Tools for making latex tables in R

I have a few tricks and work arounds to interesting 'features' of xtable and Latex that I'll share here.

Trick #1: Removing Duplicates in Columns and Trick #2: Using Booktabs

First, load packages and define my clean function

<<label=first, include=FALSE, echo=FALSE>>= 

    cleanf <- function(x){     
        oldx <- c(FALSE, x[-1]==x[-length(x)])  
        # is the value equal to the previous?    
        res <- x
        res[oldx] <- NA

Now generate some fake data

data<-data.frame(animal=sample(c("elephant", "dog", "cat", "fish", "snake"), 100,replace=TRUE),
            colour=sample(c("red", "blue", "green", "yellow"), 100,replace=TRUE),
            size=rnorm(100,mean=500, sd=150),
            age=rlnorm(100, meanlog=3, sdlog=0.5))

    #generate a table
    datatable<-ddply(data, .(animal, colour), function(df) {
                return(data.frame(size=mean(df$size), age=mean(df$age)))

Now we can generate a table, and use the clean function to remove duplicate entries in the label columns.


this is a normal xtable

<<label=normal, results=tex, echo=FALSE>>=

this is a normal xtable where a custom function has turned duplicates to NA

<<label=cleandata, results=tex, echo=FALSE>>=

This table uses the booktab package (and needs a \usepackage{booktabs} in the headers)

        \caption{table using booktabs.}
<<label=booktabs, echo=F,results=tex>>= 
            mat <- xtable(cleandata,digits=rep(2,ncol(cleandata)+1))
                  sanitize.text.function = function(x){x},
                  command=c("\\toprule ", "\\midrule ", "\\bottomrule ")))
  #could extend this with \cmidrule to have a partial line over
  #a sub category column and \addlinespace to add space before a total row

What is the meaning of the term "thread-safe"?

Instead of thinking of code or classes as thread safe or not, I think it is more helpful to think of actions as being thread-safe. Two actions are thread safe if they will be behave as specified when run from arbitrary threading contexts. In many cases, classes will support some combinations of actions in thread-safe fashion and others not.

For example, many collections like array-lists and hash sets will guarantee that if they are initially accessed exclusively with one thread, and they are never modified after a reference becomes visible to any other threads, they may be read in arbitrary fashion by any combination of threads without interference.

More interestingly, some hash-set collections such as the original non-generic one in .NET, may offer a guarantee that as long as no item is ever removed, and provided that only one thread ever writes to them, any thread that tries to read the collection will behave as though accessing a collection where updates might be delayed and occur in arbitrary order, but which will otherwise behave normally. If thread #1 adds X and then Y, and thread #2 looks for and sees Y and then X, it would be possible for thread #2 to see that Y exists but X doesn't; whether or not such behavior is "thread-safe" would depend upon whether thread #2 is prepared to deal with that possibility.

As a final note, some classes--especially blocking communications libraries--may have a "close" or "Dispose" method which is thread-safe with respect to all other methods, but no other methods that are thread-safe with respect to each other. If a thread performs a blocking read request and a user of the program clicks "cancel", there would be no way for a close request to be issued by the thread that's attempting to perform the read. The close/dispose request, however, may asynchronously set a flag which will cause the read request to be canceled as soon as possible. Once close is performed on any thread, the object would become useless, and all attempts at future actions would fail immediately, but being able to asynchronously terminate any attempted I/O operations is better than require that the close request be synchronized with the read (since if the read blocks forever, the synchronization request would be likewise blocked).

Oracle SQL Where clause to find date records older than 30 days


 WHERE creation_date <= TRUNC(SYSDATE) - 30

SYSDATE returns the date & time; TRUNC resets the date to being as of midnight so you can omit it if you want the creation_date that is 30 days previous including the current time.

Depending on your needs, you could also look at using ADD_MONTHS:

 WHERE creation_date <= ADD_MONTHS(TRUNC(SYSDATE), -1)

How do I get the raw request body from the Request.Content object using .net 4 api endpoint

For other future users who do not want to make their controllers asynchronous, or cannot access the HttpContext, or are using dotnet core (this answer is the first I found on Google trying to do this), the following worked for me:

public IActionResult Put(int pathId, int subPathId, [FromBody] myViewModel viewModel)

    var body = new StreamReader(Request.Body);
    //The modelbinder has already read the stream and need to reset the stream index
    body.BaseStream.Seek(0, SeekOrigin.Begin); 
    var requestBody = body.ReadToEnd();
    //etc, we use this for an audit trail

'if' in prolog?

You should read Learn Prolog Now! Chapter 10.2 Using Cut. This provides an example:

max(X,Y,Z) :- X =< Y,!, Y = Z.

to be said,

Z is equal to Y IF ! is true (which it always is) AND X is <= Y.

How to style the option of an html "select" element?

Bootstrap allows you to use styling via data-content:

<select class="selectpicker">
  <option data-content="<span class='label label-success'>Relish</span>">Relish</option>


Create SQL script that create database and tables

Not sure why SSMS doesn’t take into account execution order but it just doesn’t. This is not an issue for small databases but what if your database has 200 objects? In that case order of execution does matter because it’s not really easy to go through all of these.

For unordered scripts generated by SSMS you can go following

a) Execute script (some objects will be inserted some wont, there will be some errors)

b) Remove all objects from the script that have been added to database

c) Go back to a) until everything is eventually executed

Alternative option is to use third party tool such as ApexSQL Script or any other tools already mentioned in this thread (SSMS toolpack, Red Gate and others).

All of these will take care of the dependencies for you and save you even more time.

How do I check if a list is empty?

we could use a simple if else:

if len(item_list) == 0:
    print("list is empty")
    print("list is not empty")

Java correct way convert/cast object to Double

I tried this and it worked:

Object obj = 10;
String str = obj.toString(); 
double d = Double.valueOf(str).doubleValue();

Reverse a string in Java

package ThingsInArray;

public class MagicWithSelectionSort {

    public static void main(String[] arg) {

    private static void isSort(String name) {
        String revName="";
        for (int i = name.toCharArray().length-1; i >0 ; i--) {


Import numpy on pycharm

It seems that each project may have a separate collection of python libraries in a project specific computing environment. To get this working with numpy I went to the terminal at the bottom of the pycharm window and ran pip install numpy and once the process finished running the install and indexing my python project was able to import numpy from the line of code import numpy as np. It seems you may need to do this for each project you setup in numpy.

'git' is not recognized as an internal or external command

Did you open the cmd prompt before installation of git? If so, close and reopen it.

Javascript querySelector vs. getElementById

"Better" is subjective.

querySelector is the newer feature.

getElementById is better supported than querySelector.

querySelector is better supported than getElementsByClassName.

querySelector lets you find elements with rules that can't be expressed with getElementById and getElementsByClassName

You need to pick the appropriate tool for any given task.

(In the above, for querySelector read querySelector / querySelectorAll).

How do I get the object if it exists, or None if it does not exist?

Here's a variation on the helper function that allows you to optionally pass in a QuerySet instance, in case you want to get the unique object (if present) from a queryset other than the model's all objects queryset (e.g. from a subset of child items belonging to a parent instance):

def get_unique_or_none(model, queryset=None, **kwargs):
        Performs the query on the specified `queryset`
        (defaulting to the `all` queryset of the `model`'s default manager)
        and returns the unique object matching the given
        keyword arguments.  Returns `None` if no match is found.
        Throws a `model.MultipleObjectsReturned` exception
        if more than one match is found.
    if queryset is None:
        queryset = model.objects.all()
        return queryset.get(**kwargs)
    except model.DoesNotExist:
        return None

This can be used in two ways, e.g.:

  1. obj = get_unique_or_none(Model, **kwargs) as previosuly discussed
  2. obj = get_unique_or_none(Model, parent.children, **kwargs)

How can I get Apache gzip compression to work?

First of all go to apache/bin/conf/httpd.conf and make sure that is enabled.

Then go to the .htaccess file and add this line:

SetOutputFilter DEFLATE

This should output all the content served as gzipped, i have tried it and it works.

How to change the color of winform DataGridview header?

dataGridView1.ColumnHeadersDefaultCellStyle.BackColor = Color.Blue;

How to read xml file contents in jQuery and display in html elements?

 $.get("/folder_name/filename.xml", function (xml) {_x000D_
 var xmlInnerhtml = xml.documentElement.innerHTML;_x000D_

Error retrieving parent for item: No resource found that matches the given name '@android:style/TextAppearance.Holo.Widget.ActionBar.Title'

This happens because in r6 it shows an error when you try to extend private styles.

Refer to this link

How can I determine the current CPU utilization from the shell?

Maybe something like this

ps -eo pid,pcpu,comm

And if you like to parse and maybe only look at some processes.

ps -eo pid,pcpu,comm | awk '{if ($2 > 4) print }' >> ~/ps_eo_test.txt

Can (a== 1 && a ==2 && a==3) ever evaluate to true?

Here's another variation, using an array to pop off whatever values you want.

const a = {_x000D_
  n: [3,2,1],_x000D_
  toString: function () {_x000D_
    return a.n.pop();_x000D_
if(a == 1 && a == 2 && a == 3) {_x000D_

Android SDK manager won't open

I encountered a similar problem where SDK manager would flash a command window and die.

This is what worked for me: My processor and OS both are 64-bit. I had installed 64-bit JDK version. The problem wouldn't go away with reinstalling JDK or modifying path. My theory was that SDK Manager may be needed 32-bit version of JDK. Don't know why that should matter but I ended up installing 32-bit version of JDK and magic. And SDK Manager successfully launched.

How to properly seed random number generator

just to toss it out for posterity: it can sometimes be preferable to generate a random string using an initial character set string. This is useful if the string is supposed to be entered manually by a human; excluding 0, O, 1, and l can help reduce user error.

var alpha = "abcdefghijkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789"

// generates a random string of fixed size
func srand(size int) string {
    buf := make([]byte, size)
    for i := 0; i < size; i++ {
        buf[i] = alpha[rand.Intn(len(alpha))]
    return string(buf)

and I typically set the seed inside of an init() block. They're documented here:

What is the difference between Sprint and Iteration in Scrum and length of each Sprint?

"___ is largely an organizational issue caused by long hours, little down time, and continual peer, customer, and superior surveillance"

No this is not the definition of scrum, it is the wikipedia excerpt on the definition of burnout.

Dont do too many short 10 days sprints. You will burnout your team eventually. Use short sprints where you really need them, and don't do too many in a row. Think long-term. A distance runner always paces themselves for the full race and does sprints in short distances only where it matters.

If you burnout your team you can toss out all them fancy scrum charts, they won't do a thing for your team's plummeting productivity.

Maven build Compilation error : Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project Maven

This is an irritating error that pops up once in a while , jotting down some steps which help:

Writing answer from eclipse perspective as base logic will remain the same whether done by Intellij or command line

  1. Rt click your project -> Maven -> Update project -> Select Force update -> Click OK
  2. Under properties tag , add :
  1. In some instances, you will start seeing error as we tried force update saying , failure to transfer X dependency from Y path , resolutions will not be reattempted , bla bla bla

    In such case quickly fix it by cd to .m2/repository folder and run following command :

for /r %i in (*.lastUpdated) do del %i

Google Chrome Full Black Screen

If you have the Adblock extension, make sure you add the domain into the exception list. I had that problem with Google Analytics

Using the slash character in Git branch name

Are you sure branch labs does not already exist (as in this thread)?

You can't have both a file, and a directory with the same name.

You're trying to get git to do basically this:

% cd .git/refs/heads
% ls -l
total 0
-rw-rw-r-- 1 jhe jhe 41 2009-11-14 23:51 labs
-rw-rw-r-- 1 jhe jhe 41 2009-11-14 23:51 master
% mkdir labs
mkdir: cannot create directory 'labs': File exists

You're getting the equivalent of the "cannot create directory" error.
When you have a branch with slashes in it, it gets stored as a directory hierarchy under .git/refs/heads.

Can't type in React input text field

Using value={whatever} will make it so you cannot type in the input field. You should use defaultValue="Hello!".


Also, the onchange should be onChange as @davnicwil points out.

How to embed fonts in CSS?

I used Ataturk's font like this. I didn't use "TTF" version. I translated orginal font version ("otf" version) to "eot" and "woof" version. Then It works in local but not working when I uploaded the files to server. So I added "TTF" version too like this. Now, It's working on Chrome and Firefox but Internet Explorer still defence. When you installed on your computer "Ataturk" font, then working IE too. But I wanted to use this font without installing.

@font-face {
    font-family: 'Ataturk';
    font-style: normal;
    font-weight: normal;
    src: url('font/ataturk.eot');
    src: local('Ataturk Regular'), url('font/ataturk.ttf') format('truetype'), 
    url('font/ataturk.woff') format('woff');

You can see it on my website here:

Getting the parent of a directory in Bash

parentdir="$(dirname "$dir")"

Works if there is a trailing slash, too.

How to display text in pygame?

When displaying I sometimes make a new file called Funk. This will have the font, size etc. This is the code for the class:

import pygame

def text_to_screen(screen, text, x, y, size = 50,
            color = (200, 000, 000), font_type = 'data/fonts/orecrusherexpand.ttf'):

        text = str(text)
        font = pygame.font.Font(font_type, size)
        text = font.render(text, True, color)
        screen.blit(text, (x, y))

    except Exception, e:
        print 'Font Error, saw it coming'
        raise e

Then when that has been imported when I want to display text taht updates E.G score I do:

Funk.text_to_screen(screen, 'Text {0}'.format(score), xpos, ypos)

If it is just normal text that isn't being updated:

Funk.text_to_screen(screen, 'Text', xpos, ypos)

You may notice {0} on the first example. That is because when .format(whatever) is used that is what will be updated. If you have something like Score then target score you'd do {0} for score then {1} for target score then .format(score, targetscore)

How can I send JSON response in symfony2 controller

Since Symfony 3.1 you can use JSON Helper

public function indexAction()
// returns '{"username":"jane.doe"}' and sets the proper Content-Type header
return $this->json(array('username' => 'jane.doe'));

// the shortcut defines three optional arguments
// return $this->json($data, $status = 200, $headers = array(), $context = array());

When to use DataContract and DataMember attributes?

  1. Data contract: It specifies that your entity class is ready for Serialization process.

  2. Data members: It specifies that the particular field is part of the data contract and it can be serialized.

UnicodeEncodeError: 'latin-1' codec can't encode character

Latin-1 (aka ISO 8859-1) is a single octet character encoding scheme, and you can't fit \u201c () into a byte.

Did you mean to use UTF-8 encoding?

How to put space character into a string name in XML?

If the output is HTML, then in HTML multiple spaces display as a single space. To prevent this, use non-breaking spaces (xA0) instead of ordinary spaces.

How can one display images side by side in a GitHub

This is the best way to make add images/screenshots of your app and keep your repository look clean.

Create a screenshot folder in your repository and add the images you want to display.

Now go to and add this HTML code to form a table.

#### Flutter App Screenshots

    <td>First Screen Page</td>
     <td>Holiday Mention</td>
     <td>Present day in purple and selected day in pink</td>
    <td><img src="screenshots/Screenshot_1582745092.png" width=270 height=480></td>
    <td><img src="screenshots/Screenshot_1582745125.png" width=270 height=480></td>
    <td><img src="screenshots/Screenshot_1582745139.png" width=270 height=480></td>

In the <td><img src="(COPY IMAGE PATH HERE)" width=270 height=480></td>

** To get the image path --> Go to the screenshot folder and open the image and on the right most side, you will find Copy path button.

You will get a table like this in your repository--->

enter image description here

How to make an HTML back link?

<a href="#" onclick="history.back();">Back</a>

Prevent double curly brace notation from displaying momentarily before angular.js compiles/interpolates document

I think that you are looking for the ngCloak directive:

From the documentation:

The ngCloak directive is used to prevent the Angular html template from being briefly displayed by the browser in its raw (uncompiled) form while your application is loading. Use this directive to avoid the undesirable flicker effect caused by the html template display.

The directive can be applied to the <body> element, but the preferred usage is to apply multiple ngCloak directives to small portions of the page to permit progressive rendering of the browser view

How can one see the structure of a table in SQLite?

PRAGMA table_info(table_name);

This will work for both: command-line and when executed against a connected database.

A link for more details and example. thanks SQLite Pragma Command

Problem in running .net framework 4.0 website on iis 7.0

If you look in the ISAPI And CGI Restrictions, and everything is already set to Allowed, and the ASP.NET installed is v4.0.30319, then in the right, at the "Actions" panel click in the "Edit Feature Settings..." and check both boxes. In my case, they were not.

Incompatible implicit declaration of built-in function ‘malloc’

The only solution for such warnings is to include stdlib.h in the program.

session handling in jquery

In my opinion you should not load and use plugins you don't have to. This particular jQuery plugin doesn't give you anything since directly using the JavaScript sessionStorage object is exactly the same level of complexity. Nor, does the plugin provide some easier way to interact with other jQuery functionality. In addition the practice of using a plugin discourages a deep understanding of how something works. sessionStorage should be used only if its understood. If its understood, then using the jQuery plugin is actually MORE effort.

Consider using sessionStorage directly:

How to capture a list of specific type with mockito

If you're not afraid of old java-style (non type safe generic) semantics, this also works and is simple'ish:

ArgumentCaptor<List> argument = ArgumentCaptor.forClass(List.class);
verify(subject.method(argument.capture()); // run your code
List<SomeType> list = argument.getValue(); // first captured List, etc.

Inserting records into a MySQL table using Java

This should work for any table, instead of hard-coding the columns.

//Source details_x000D_
    String sourceUrl = "jdbc:oracle:thin:@//server:1521/db";_x000D_
    String sourceUserName = "src";_x000D_
    String sourcePassword = "***";_x000D_
    // Destination details_x000D_
    String destinationUserName = "dest";_x000D_
    String destinationPassword = "***";_x000D_
    String destinationUrl = "jdbc:mysql://server:3306/db";_x000D_
    Connection srcConnection = getSourceConnection(sourceUrl, sourceUserName, sourcePassword);_x000D_
    Connection destConnection = getDestinationConnection(destinationUrl, destinationUserName, destinationPassword);_x000D_
    PreparedStatement sourceStatement = srcConnection.prepareStatement("SELECT *  FROM src_table ");_x000D_
    ResultSet rs = sourceStatement.executeQuery();_x000D_
    rs.setFetchSize(1000); // not needed_x000D_
    ResultSetMetaData meta = rs.getMetaData();_x000D_
    List<String> columns = new ArrayList<>();_x000D_
    for (int i = 1; i <= meta.getColumnCount(); i++)_x000D_
    try (PreparedStatement destStatement = destConnection.prepareStatement(_x000D_
            "INSERT INTO dest_table ("_x000D_
                    +", "))_x000D_
                    + ") VALUES ("_x000D_
                    + -> "?").collect(Collectors.joining(", "))_x000D_
                    + ")"_x000D_
        int count = 0;_x000D_
        while ( {_x000D_
            for (int i = 1; i <= meta.getColumnCount(); i++) {_x000D_
                destStatement.setObject(i, rs.getObject(i));_x000D_
        destStatement.executeBatch(); // you will see all the rows in dest once this statement is executed_x000D_
        System.out.println("done " + count);_x000D_

Getting the "real" Facebook profile picture URL from graph API

$url = '';
$hd = $rray[4];

This will return the url that you asked, and the problem of changing the url by facebook doesn't matter because you are dynamically calling the url from the original url.

Python: CSV write by column rather than row

Updating lines in place in a file is not supported on most file system (a line in a file is just some data that ends with newline, the next line start just after that).

As I see it you have two options:

  1. Have your data generating loops be generators, this way they won't consume a lot of memory - you'll get data for each row "just in time"
  2. Use a database (sqlite?) and update the rows there. When you're done - export to CSV

Small example for the first method:

from itertools import islice, izip, count
print list(islice(izip(count(1), count(2), count(3)), 10))

This will print

[(1, 2, 3), (2, 3, 4), (3, 4, 5), (4, 5, 6), (5, 6, 7), (6, 7, 8), (7, 8, 9), (8, 9, 10), (9, 10, 11), (10, 11, 12)]

even though count generate an infinite sequence of numbers

How to print without newline or space?

The new (as of Python 3.x) print function has an optional end parameter that lets you modify the ending character:

print("HELLO", end="")



There's also sep for separator:

print("HELLO", "HELLO", "HELLO", sep="")



If you wanted to use this in Python 2.x just add this at the start of your file:

from __future__ import print_function

What's the best way to join on the same table twice?

First, I would try and refactor these tables to get away from using phone numbers as natural keys. I am not a fan of natural keys and this is a great example why. Natural keys, especially things like phone numbers, can change and frequently so. Updating your database when that change happens will be a HUGE, error-prone headache. *

Method 1 as you describe it is your best bet though. It looks a bit terse due to the naming scheme and the short aliases but... aliasing is your friend when it comes to joining the same table multiple times or using subqueries etc.

I would just clean things up a bit:

SELECT t.PhoneNumber1, t.PhoneNumber2, 
   t1.SomeOtherFieldForPhone1, t2.someOtherFieldForPhone2
FROM Table1 t
JOIN Table2 t1 ON t1.PhoneNumber = t.PhoneNumber1
JOIN Table2 t2 ON t2.PhoneNumber = t.PhoneNumber2

What i did:

  • No need to specify INNER - it's implied by the fact that you don't specify LEFT or RIGHT
  • Don't n-suffix your primary lookup table
  • N-Suffix the table aliases that you will use multiple times to make it obvious

*One way DBAs avoid the headaches of updating natural keys is to not specify primary keys and foreign key constraints which further compounds the issues with poor db design. I've actually seen this more often than not.

Make a dictionary in Python from input values

n = int(input())          #n is the number of items you want to enter
d ={}                     
for i in range(n):        
    text = input().split()     #split the input text based on space & store in the list 'text'
    d[text[0]] = text[1]       #assign the 1st item to key and 2nd item to value of the dictionary



A1023 CRT

A1029 Regulator

A1030 Therm

NOTE: I have added an extra line for each input for getting each input on individual lines on this site. As placing without an extra line creates a single line.


{'A1023': 'CRT', 'A1029': 'Regulator', 'A1030': 'Therm'}

Read a plain text file with php

You can also produce array by using file:

$array = file('/path/to/text.txt');

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

You have make div as server control using following code,

<div class="tab-pane active" id="portlet_tab1" runat="server">

then this div will be accessible in code behind.

Equivalent to AssemblyInfo in dotnet core/csproj

Adding to NightOwl888's answer, you can go one step further and add an AssemblyInfo class rather than just a plain class:

enter image description here

Open Cygwin at a specific folder

Here's what I use. It doesn't require chere package or registry tinkering. Works on Windows 7.

Go to your "Send To" folder:


Create a shortcut named Bash Here having this in the Target field:

C:\cygwin\bin\mintty.exe -i /Cygwin-Terminal.ico  C:\cygwin\bin\bash.exe  -l -c "cd \"$0\" ; exec bash"

In the Windows Explorer, you right-click on a folder & select Send To > Bash Here.

And here's the opposite trick, opening a Windows Explorer in your current bash dir. Create this alias:

alias winx='/cygdrive/c/Windows/explorer.exe /e,\`cygpath -w .\`'

Note: the cygpath -w . part above is enclosed in back-ticks.

Now just type winx at the bash prompt, and a Win Explorer pops up there.

Note: If winx directs you to your documents folder, try

alias winx='/cygdrive/c/Windows/explorer.exe /e,`cygpath -w $PWD`'

What is "Signal 15 received"

This indicates the linux has delivered a SIGTERM to your process. This is usually at the request of some other process (via kill()) but could also be sent by your process to itself (using raise()). This signal requests an orderly shutdown of your process.

If you need a quick cheatsheet of signal numbers, open a bash shell and:

$ kill -l
63) SIGRTMAX-1  64) SIGRTMAX    

You can determine the sender by using an appropriate signal handler like:

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

void sigterm_handler(int signal, siginfo_t *info, void *_unused)
  fprintf(stderr, "Received SIGTERM from process with pid = %u\n",

int main (void)
  struct sigaction action = {
    .sa_handler = NULL,
    .sa_sigaction = sigterm_handler,
    .sa_mask = 0,
    .sa_flags = SA_SIGINFO,
    .sa_restorer = NULL

  sigaction(SIGTERM, &action, NULL);

  return 0;

Notice that the signal handler also includes a call to exit(). It's also possible for your program to continue to execute by ignoring the signal, but this isn't recommended in general (if it's a user doing it there's a good chance it will be followed by a SIGKILL if your process doesn't exit, and you lost your opportunity to do any cleanup then). localhost/ - Connection refused

its working for me. I use genymotion for Run App.

1.Firstly i was checked my local ip. goto command mode>> And write ipconfig. Example: Windows 10>> search cmd>>then Write ipconfig . 2. Then get your local ip information >>> 3.Use give your localhost ip and virtual box ip. You need to use virtual box ip for genymotion.Check below screenshot. You can you below any ip under virtualbox host network enter image description here

Windows: XAMPP vs WampServer vs EasyPHP vs alternative

EasyPHP is very good :

  • lightweight & portable : no windows service (like wamp)
  • easy to configure (all configuration files in the same folder : httpd.conf, php.ini & my.ini)
  • auto restarts apache when you edit httpd.conf

WAMP or UWAMP are good choices if you need to test with multiples versions of PHP and Apache.

But you can also use multiple versions of PHP with EasyPHP (by downloading the PHP version you need on, and loading this version by editing httpd.conf) :

LoadModule php4_module "${path}/php4/php4apache2_2.dll"

Static extension methods

No, but you could have something like:

bool b;
b = b.YourExtensionMethod();

Configure active profile in SpringBoot via Maven

The Maven profile and the Spring profile are two completely different things. Your pom.xml defines variable which is available in the build process, but not at runtime. That is why only the default profile is activated.

How to bind Maven profile with Spring?

You need to pass the build variable to your application so that it is available when it is started.

  1. Define a placeholder in your

    [email protected]@

    The variable must match the declared property from the Maven profile.

  2. Enable resource filtering in you pom.xml:


    When the build is executed, all files in the src/main/resources directory will be processed by Maven and the placeholder in your will be replaced with the variable you defined in your Maven profile.

For more details you can go to my post where I described this use case.

Clear text field value in JQuery

If you want to clear the text field, use:


Removing duplicate characters from a string

from collections import OrderedDict
def remove_duplicates(value):
        for i in m:
        return s

Check/Uncheck all the checkboxes in a table

This will select and deselect all checkboxes:

function checkAll()
     var checkboxes = document.getElementsByTagName('input'), val = null;    
     for (var i = 0; i < checkboxes.length; i++)
         if (checkboxes[i].type == 'checkbox')
             if (val === null) val = checkboxes[i].checked;
             checkboxes[i].checked = val;



You can use querySelectAll directly on the table to get the list of checkboxes instead of searching the whole document, but It might not be compatible with old browsers so you need to check that first:

 function checkAll()
     var table = document.getElementById ('dataTable');
     var checkboxes = table.querySelectorAll ('input[type=checkbox]');
     var val = checkboxes[0].checked;
     for (var i = 0; i < checkboxes.length; i++) checkboxes[i].checked = val;

Or to be more specific for the provided html structure in the OP question, this would be more efficient when selecting the checkboxes as it will access them directly instead of searching for them:

function checkAll (tableID)
    var table = document.getElementById (tableID);
    var val = table.rows[0].cells[0].children[0].checked;
    for (var i = 1; i < table.rows.length; i++)
        table.rows[i].cells[0].children[0].checked = val;


Is there a program to decompile Delphi?

Languages like Delphi, C and C++ Compile to processor-native machine code, and the output executables have little or no metadata in them. This is in contrast with Java or .Net, which compile to object-oriented platform-independent bytecode, which retains the names of methods, method parameters, classes and namespaces, and other metadata.

So there is a lot less useful decompiling that can be done on Delphi or C code. However, Delphi typically has embedded form data for any form in the project (generated by the $R *.dfm line), and it also has metadata on all published properties, so a Delphi-specific tool would be able to extract this information.

Trimming text strings in SQL Server 2008

You can use the RTrim function to trim all whitespace from the right. Use LTrim to trim all whitespace from the left. For example

UPDATE Table SET Name = RTrim(Name)

Or for both left and right trim

UPDATE Table SET Name = LTrim(RTrim(Name))

How can I use a batch file to write to a text file?

You can use echo, and redirect the output to a text file (see notes below):

rem Saved in D:\Temp\WriteText.bat
@echo off
echo This is a test> test.txt
echo 123>> test.txt
echo 245.67>> test.txt



D:\Temp>type test.txt
This is a test



  • @echo off turns off printing of each command to the console
  • Unless you give it a specific path name, redirection with > or >> will write to the current directory (the directory the code is being run in).
  • The echo This is a test > test.txt uses one > to overwrite any file that already exists with new content.
  • The remaining echo statements use two >> characters to append to the text file (add to), instead of overwriting it.
  • The type test.txt simply types the file output to the command window.

How do I set up access control in SVN?

Apache Subversion supports path-based authorization that helps you configure granular permissions for user and group accounts on paths in your repositories (files or directories). Path-based authorization supports three access levels - No Access, Read Only and Read / Write.

Path-based authorization permissions are stored in per-repository or per-server authorization files with a special syntax. Here is an example from SVNBook:

harry = rw
sally = r

When you require a complex permission structure with many paths and accounts you can benefit from a GUI-based permission management tools provided by VisualSVN Server:

  • Server administrators can manage user and group permissions via the VisualSVN Server Manager console or PowerShell,
  • Non-admin users can manage permissions via RepoCfg.

Repository permissions in VisualSVN Server Manager enter image description here

Repository permissions in PowerShell enter image description here

Non-admin users can manage permissions via the RepoCfg tool enter image description here

"The system cannot find the file specified"

Considering that a LocalDb instance only intended for use in development. LocalDb is not available for production servers When you deploy the final result.

I think your connection string is pointing to a LocalDb instance and you need to take certain steps to turn it into the SQL Server database. It's not just a matter of copying an mdf file either. It will possibly differ from one hosting company to another, but typically, you need to create a backup of your existing database (a .bak file) and then restore that to the hosting company's SQL Server. You should ask them where you can find instructions on deploying your database into production.

How to embed a Facebook page's feed into my website

If you are looking for a custom code instead of plugin, then this might help you. Facebook graph has under gone some changes since it has evolved. These steps are for the latest Graph API which I tried recently and worked well.

There are two main steps involved - 1. Getting Facebook Access Token, 2. Calling the Graph API passing the access token.

1. Getting the access token - Here is the step by step process to get the access token for your Facebook page. - Embed Facebook page feed on my website. As per this you need to create an app in Facebook developers page which would give you an App Id and an App Secret. Use these two and get the Access Token.

2. Calling the Graph API - This would be pretty simple once you get the access token. You just need to form a URL to Graph API with all the fields/properties you want to retrieve and make a GET request to this URL. Here is one example on how to do it in MVC. Embedding facebook feeds using mvc. This should be pretty similar in any other technology as it would be just a HTTP GET request.

Sample FQL Query:,picture,link,message,created_time&limit=5&access_token=YOUR_ACCESS_TOKEN_HERE

HTML text input allow only numeric input

I realize an old post but i thought this could help someone. Recently I had to limit a text box to just 5 decimal places. In my case ALSO the users input had to be less than 0.1

<input type="text" value="" maxlength=7 style="width:50px" id="fmargin" class="formText"  name="textfield" onkeyup="return doCheck('#fmargin',event);">

Here is the doCheck function

function doCheck(id,evt)
    var temp=parseFloat($(id).val());

    if (isNaN(temp))
    if (temp==0)


Here is the same function except to force integer input

function doCheck(id,evt)
    var temp=parseInt($(id).val());

    if (isNaN(temp))


hope that helps someone

ReferenceError: variable is not defined

Got the error (in the function init) with the following code ;

"use strict" ;

var hdr ;

function init(){ // called on load
    hdr = document.getElementById("hdr");

... while using the stock browser on a Samsung galaxy Fame ( crap phone which makes it a good tester ) - userAgent ; Mozilla/5.0 (Linux; U; Android 4.1.2; en-gb; GT-S6810P Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30

The same code works everywhere else I tried including the stock browser on an older HTC phone - userAgent ; Mozilla/5.0 (Linux; U; Android 2.3.5; en-gb; HTC_WildfireS_A510e Build/GRJ90) AppleWebKit/533.1 (KHTML, like Gecko) Version/4.0 Mobile Safari/533.1

The fix for this was to change

var hdr ;


var hdr = null ;

ActiveXObject is not defined and can't find variable: ActiveXObject

A web app can request access to a sandboxed file system by calling window.requestFileSystem(). Works in Chrome.

window.requestFileSystem = window.requestFileSystem || window.webkitRequestFileSystem;
var fs = null;

window.requestFileSystem(window.TEMPORARY, 1024 * 1024, function (filesystem) {
    fs = filesystem;
}, errorHandler);

fs.root.getFile('Hello.txt', {
    create: true
}, null, errorHandler);

function errorHandler(e) {
  var msg = '';

  switch (e.code) {
    case FileError.QUOTA_EXCEEDED_ERR:
      msg = 'QUOTA_EXCEEDED_ERR';
    case FileError.NOT_FOUND_ERR:
      msg = 'NOT_FOUND_ERR';
    case FileError.SECURITY_ERR:
      msg = 'SECURITY_ERR';
    case FileError.INVALID_STATE_ERR:
      msg = 'INVALID_STATE_ERR';
      msg = 'Unknown Error';

  console.log('Error: ' + msg);

More info here.


In SQL without SELECT you cannot result anything. Instead of IF-ELSE block I prefer to use CASE statement for this

                      FROM   tblGLUserAccess
                      WHERE  GLUserName = 'xxxxxxxx') THEN 1
         ELSE 2

How to have Ellipsis effect on Text

const styles = theme => ({_x000D_
    overflow: 'hidden',_x000D_
    textOverflow: 'ellipsis',_x000D_
    display: '-webkit-box',_x000D_
 }   _x000D_
render () {_x000D_
    <div className={classes.contentClass}>_x000D_

Free XML Formatting tool

Try The algorithm is similar to HTML Tidy, but is more complete. The program is written entirely in JavaScript, so you don't have to install anything.

Space between two divs

DIVs inherently lack any useful meaning, other than to divide, of course.

Best course of action would be to add a meaningful class name to them, and style their individual margins in CSS.

<h1>Important Title</h1>
<div class="testimonials">...</div>
<div class="footer">...</div>

h1 {margin-bottom: 0.1em;}
div.testimonials {margin-bottom: 0.2em;}
div.footer {margin-bottom: 0;}

Safe width in pixels for printing web pages?

I doubt there is one... It depends on browser, on printer (physical max dpi) and its driver, on paper size as you point out (and I might want to print on B5 paper too...), on settings (landscape or portrait?), plus you often can change the scale (percentage), etc.
Let the users tweak their settings...

How to initialize a dict with keys from a list and empty value in Python?

>>> keyDict = {"a","b","c","d"}

>>> dict([(key, []) for key in keyDict])


{'a': [], 'c': [], 'b': [], 'd': []}

Could not transfer artifact org.apache.maven.plugins:maven-surefire-plugin:pom:2.7.1 from/to central (

We have the Proxy set on company level.

After disabling proxy in Internet Explorer this issue was solved (looks like it is then disabled on 'system' level), so all other browsers will pick this change too.

Now I can issue MVN commands from CMD prompt and I have no problem while e.g.


...that was causing 'Build failure'

Disabling proxy in IE needs to be done on daily basis in our case, because on each system start it gets set

Output ("echo") a variable to a text file

Here is an easy one:

$myVar > "c:\myfilepath\myfilename.myextension"

You can also try:

Get-content "c:\someOtherPath\someOtherFile.myextension" > "c:\myfilepath\myfilename.myextension"

Simple int to char[] conversion

If you want to convert an int which is in the range 0-9 to a char, you may usually write something like this:

int x;
char c = '0' + x;

Now, if you want a character string, just add a terminating '\0' char:

char s[] = {'0' + x, '\0'};

Note that:

  1. You must be sure that the int is in the 0-9 range, otherwise it will fail,
  2. It works only if character codes for digits are consecutive. This is true in the vast majority of systems, that are ASCII-based, but this is not guaranteed to be true in all cases.

How to unapply a migration in ASP.NET Core with EF Core

Note: It might be troublesome later on, I used it as a last resort since non of the solutions provided above and others did not work in my case:

  1. Copy the code from the body of previous successful migration's down() method.
  2. Add a new migration using Add-Migration "migration-name"
  3. Paste the copied code from the down() method of previous migration to the new migration's Up() method:
    Up(){ //paste here }
  4. Run Update-Database
  5. Done, your changes from the previous migration should now have been reverted!

Difference between CR LF, LF and CR line break types?

This is a good summary I found:

The Carriage Return (CR) character (0x0D, \r) moves the cursor to the beginning of the line without advancing to the next line. This character is used as a new line character in Commodore and Early Macintosh operating systems (OS-9 and earlier).

The Line Feed (LF) character (0x0A, \n) moves the cursor down to the next line without returning to the beginning of the line. This character is used as a new line character in UNIX based systems (Linux, Mac OSX, etc)

The End of Line (EOL) sequence (0x0D 0x0A, \r\n) is actually two ASCII characters, a combination of the CR and LF characters. It moves the cursor both down to the next line and to the beginning of that line. This character is used as a new line character in most other non-Unix operating systems including Microsoft Windows, Symbian OS and others.


Printf width specifier to maintain precision of floating-point value

To my knowledge, there is a well diffused algorithm allowing to output to the necessary number of significant digits such that when scanning the string back in, the original floating point value is acquired in dtoa.c written by Daniel Gay, which is available here on Netlib (see also the associated paper). This code is used e.g. in Python, MySQL, Scilab, and many others.

pip installs packages successfully, but executables not found from command line

When you install Python or Python3 using MacOS installer (downloaded from Python website) - it adds an exporter to your ~/.profile script. All you need to do is just source it. Restarting all the terminals should also do the trick.

WARNING - I believe it's better to just use pip3 with Python3 - for future benefits.

If you already have Python3 installed, the following steps work for me on macOS Mojave:

  1. Install ansible first using sudo - sudo -H pip3 install ansible

  2. you create a symlink to the Python's bin path

sudo ln -s /Library/Frameworks/Python.framework/Versions/Current/bin /Library/Frameworks/Python.framework/current_python_bin

and staple it to .profile

export PATH=$PATH:/Library/Frameworks/Python.framework/current_python_bin

  1. run source ~/.profile and restart all terminal shells.

  2. Type ansible --version

How to add leading zeros?

For other circumstances in which you want the number string to be consistent, I made a function.

Someone may find this useful:

idnamer<-function(x,y){#Alphabetical designation and number of integers required
    for (i in 1:length(id)){

Sorry about the formatting.

How do I replace text inside a div element?

$('field_name').innerHTML = 'Your text.';

One of the nifty features of Prototype is that $('field_name') does the same thing as document.getElementById('field_name'). Use it! :-)

John Topley's answer using Prototype's update function is another good solution.

How to create a md5 hash of a string in C?

To be honest, the comments accompanying the prototypes seem clear enough. Something like this should do the trick:

void compute_md5(char *str, unsigned char digest[16]) {
    MD5Context ctx;
    MD5Update(&ctx, str, strlen(str));
    MD5Final(digest, &ctx);

where str is a C string you want the hash of, and digest is the resulting MD5 digest.

LINQ-to-SQL vs stored procedures?

Linq to Sql.

Sql server will cache the query plans, so there's no performance gain for sprocs.

Your linq statements, on the other hand, will be logically part of and tested with your application. Sprocs are always a bit separated and are harder to maintain and test.

If I was working on a new application from scratch right now I would just use Linq, no sprocs.

Java resource as file

ClassLoader.getResourceAsStream and Class.getResourceAsStream are definitely the way to go for loading the resource data. However, I don't believe there's any way of "listing" the contents of an element of the classpath.

In some cases this may be simply impossible - for instance, a ClassLoader could generate data on the fly, based on what resource name it's asked for. If you look at the ClassLoader API (which is basically what the classpath mechanism works through) you'll see there isn't anything to do what you want.

If you know you've actually got a jar file, you could load that with ZipInputStream to find out what's available. It will mean you'll have different code for directories and jar files though.

One alternative, if the files are created separately first, is to include a sort of manifest file containing the list of available resources. Bundle that in the jar file or include it in the file system as a file, and load it before offering the user a choice of resources.

ORA-01461: can bind a LONG value only for insert into a LONG column-Occurs when querying

A collegue of me and I found out the following:

When we use the Microsoft .NET Oracle driver to connect to an oracle Database (System.Data.OracleClient.OracleConnection)

And we are trying to insert a string with a length between 2000 and 4000 characters into an CLOB or NCLOB field using a database-parameter

// Add string-parameters with different lengths
// oraCommand.Parameters.Add("PARAMETER1", new string(' ', 1900)); // ok
oraCommand.Parameters.Add("PARAMETER1", new string(' ', 2500));  // Exception
//oraCommand.Parameters.Add("PARAMETER1", new string(' ', 4100)); // ok
  • any string with a length under 2000 characters will not throw this exception
  • any string with a length of more than 4000 characters will not throw this exception
  • only strings with a length between 2000 and 4000 characters will throw this exception

We opened a ticket at microsoft for this bug many years ago, but it has still not been fixed.

Read/write to file using jQuery

both HTML5 and Google Gears add local storage capabilities, mainly by an embedded SQLite API.

SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens on line 102

You didn't bind all your bindings here

$sql = "SELECT SQL_CALC_FOUND_ROWS *, UNIX_TIMESTAMP(publicationDate) AS publicationDate     FROM comments WHERE articleid = :art 
ORDER BY " . mysqli_escape_string($order) . " LIMIT :numRows";

$st = $conn->prepare( $sql );
$st->bindValue( ":art", $art, PDO::PARAM_INT );

You've declared a binding called :numRows but you never actually bind anything to it.

UPDATE 2019: I keep getting upvotes on this and that reminded me of another suggestion

Double quotes are string interpolation in PHP, so if you're going to use variables in a double quotes string, it's pointless to use the concat operator. On the flip side, single quotes are not string interpolation, so if you've only got like one variable at the end of a string it can make sense, or just use it for the whole string.

In fact, there's a micro op available here since the interpreter doesn't care about parsing the string for variables. The boost is nearly unnoticable and totally ignorable on a small scale. However, in a very large application, especially good old legacy monoliths, there can be a noticeable performance increase if strings are used like this. (and IMO, it's easier to read anyway)

How to use the pass statement?

The best and most accurate way to think of pass is as a way to explicitly tell the interpreter to do nothing. In the same way the following code:

def foo(x,y):
    return x+y

means "if I call the function foo(x, y), sum the two numbers the labels x and y represent and hand back the result",

def bar():

means "If I call the function bar(), do absolutely nothing."

The other answers are quite correct, but it's also useful for a few things that don't involve place-holding.

For example, in a bit of code I worked on just recently, it was necessary to divide two variables, and it was possible for the divisor to be zero.

c = a / b

will, obviously, produce a ZeroDivisionError if b is zero. In this particular situation, leaving c as zero was the desired behavior in the case that b was zero, so I used the following code:

    c = a / b
except ZeroDivisionError:

Another, less standard usage is as a handy place to put a breakpoint for your debugger. For example, I wanted a bit of code to break into the debugger on the 20th iteration of a for... in statement. So:

for t in range(25):
    if t == 20:

with the breakpoint on pass.

Count number of days between two dates

Very late, but it may help others:

end_date.mjd - start_date.mjd

How to disable HTML button using JavaScript?

Try the following:

document.getElementById("id").setAttribute("disabled", "disabled");