Programs & Examples On #Ksoap

kSOAP is a SOAP web service client library for constrained Java environments such as Applets or J2ME applications.

How to call a .NET Webservice from Android using KSOAP2?

You can Use below code to call the web service and get response .Make sure that your Web Service return the response in Data Table Format..This code help you if you using data from SQL Server database .If you you using MYSQL you need to change one thing just replace word NewDataSet from sentence obj2=(SoapObject) obj1.getProperty("NewDataSet"); by DocumentElement

private static final String NAMESPACE = "";
private static final String URL = "http://localhost/Web_Service.asmx?"; // you can use   IP address instead of localhost
private static final String METHOD_NAME = "Function_Name";
private static final String SOAP_ACTION = NAMESPACE + METHOD_NAME;

SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
request.addProperty("parm_name", prm_value); // Parameter for Method
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
envelope.dotNet = true;
HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);

try {, envelope); //call the eb service Method
} catch (Exception e) {
} //Next task is to get Response and format that response

SoapObject obj, obj1, obj2, obj3;
obj = (SoapObject) envelope.getResponse();
obj1 = (SoapObject) obj.getProperty("diffgram");
obj2 = (SoapObject) obj1.getProperty("NewDataSet");

for (int i = 0; i < obj2.getPropertyCount(); i++) //the method getPropertyCount() return the number of rows
    obj3 = (SoapObject) obj2.getProperty(i);
    obj3.getProperty(0).toString(); //value of column 1
    obj3.getProperty(1).toString(); //value of column 2
    //like that you will get value from each column

If you have any problem regarding this you can write me..

Sum of values in an array using jQuery

    var arr = ["20.0","40.1","80.2","400.3"],
    sum = 0;
$.each(arr,function(){sum+=parseFloat(this) || 0; });

Worked perfectly for what i needed. Thanks vol7ron

Is there a way to make numbers in an ordered list bold?

I had a similar issue while writing a newsletter. So I had to inline the style this way:

    <li style="font-weight:bold"><span style="font-weight:normal">something</span></li>
    <li style="font-weight:bold"><span style="font-weight:normal">something</span></li>
    <li style="font-weight:bold"><span style="font-weight:normal">something</span></li>

Inheriting from a template class in c++

Make Rectangle a template and pass the typename on to Area:

template <typename T>
class Rectangle : public Area<T>


How to initialise memory with new operator in C++?

Typically for dynamic lists of items, you use a std::vector.

Generally I use memset or a loop for raw memory dynamic allocation, depending on how variable I anticipate that area of code to be in the future.

Converting JavaScript object with numeric keys into array

Here is an example of how you could get an array of objects and then sort the array.

  function osort(obj)
  {  // map the object to an array [key, obj[key]]
    return Object.keys(obj).map(function(key) { return [key, obj[key]] }).sort(
      function (keya, keyb)
      { // sort(from largest to smallest)
          return keyb[1] - keya[1];

VBA Count cells in column containing specified value

This isn't exactly what you are looking for but here is how I've approached this problem in the past;

You can enter a formula like;


...into a cell. This will count the Number of cells between A1 and A10 that contain the text "Green". You can then select this cell value in a VBA Macro and assign it to a variable as normal.

Pass C# ASP.NET array to Javascript array

For array of objects:

var array= JSON.parse('@Newtonsoft.Json.JsonConvert.SerializeObject(numbers)'.replace(/&quot;/g, "\""));

For array of int:

 var array= JSON.parse('@Newtonsoft.Json.JsonConvert.SerializeObject(numbers)');

Get all child elements

Here is a code to get the child elements (In java):

String childTag = childElement.getTagName();
    return "/html[1]"+current;
WebElement parentElement = childElement.findElement(By.xpath("..")); 
List<WebElement> childrenElements = parentElement.findElements(By.xpath("*"));
int count = 0;
for(int i=0;i<childrenElements.size(); i++) 
    WebElement childrenElement = childrenElements.get(i);
    String childrenElementTag = childrenElement.getTagName();

How to display custom view in ActionBar?

For example, you can define a layout file which contains a EditText element.

<?xml version="1.0" encoding="utf-8"?>
<EditText xmlns:android=""
    android:inputType="textFilter" >


you can do

public class MainActivity extends Activity {

  protected void onCreate(Bundle savedInstanceState) {

    ActionBar actionBar = getActionBar();
    // add the custom view to the action bar
    EditText search = (EditText) actionBar.getCustomView().findViewById(;
    search.setOnEditorActionListener(new OnEditorActionListener() {

      public boolean onEditorAction(TextView v, int actionId,
          KeyEvent event) {
        Toast.makeText(MainActivity.this, "Search triggered",
        return false;
        | ActionBar.DISPLAY_SHOW_HOME);


Enum to String C++

Kind of an anonymous lookup table rather than a long switch statement:

return (const char *[]) {
    "bananas & monkeys",
    "Round and orange", 

Find index of last occurrence of a sub-string using T-SQL

Old but still valid question, so heres what I created based on the info provided by others here.

create function fnLastIndexOf(@text varChar(max),@char varchar(1))
returns int
return len(@text) - charindex(@char, reverse(@text)) -1

ansible : how to pass multiple commands

If a value in YAML begins with a curly brace ({), the YAML parser assumes that it is a dictionary. So, for cases like this where there is a (Jinja2) variable in the value, one of the following two strategies needs to be adopted to avoiding confusing the YAML parser:

Quote the whole command:

- command: "{{ item }} chdir=/src/package/"
  - ./configure
  - /usr/bin/make
  - /usr/bin/make install    

or change the order of the arguments:

- command: chdir=/src/package/ {{ item }}
  - ./configure
  - /usr/bin/make
  - /usr/bin/make install

Thanks for @RamondelaFuente alternative suggestion.

CMake link to external library

Set libraries search path first:


And then just do


'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension method

Make sure that you have installed the correct NuGet package in your console application:

<package id="Microsoft.AspNet.WebApi.Client" version="4.0.20710.0" />

and that you are targeting at least .NET 4.0.

This being said, your GetAllFoos function is defined to return an IEnumerable<Prospect> whereas in your ReadAsAsync method you are passing IEnumerable<Foo> which obviously are not compatible types.

Install-Package Microsoft.AspNet.WebApi.Client

Select project in project manager console

How to convert CharSequence to String?

There is a subtle issue here that is a bit of a gotcha.

The toString() method has a base implementation in Object. CharSequence is an interface; and although the toString() method appears as part of that interface, there is nothing at compile-time that will force you to override it and honor the additional constraints that the CharSequence toString() method's javadoc puts on the toString() method; ie that it should return a string containing the characters in the order returned by charAt().

Your IDE won't even help you out by reminding that you that you probably should override toString(). For example, in intellij, this is what you'll see if you create a new CharSequence implementation: Note the absence of toString().

If you rely on toString() on an arbitrary CharSequence, it should work provided the CharSequence implementer did their job properly. But if you want to avoid any uncertainty altogether, you should use a StringBuilder and append(), like so:

final StringBuilder sb = new StringBuilder(charSequence.length());
return sb.toString();

How can I get the domain name of my site within a Django template?

In a Django template you can do:

<a href="{{ request.scheme }}://{{ request.META.HTTP_HOST }}{{ request.path }}?{{ request.GET.urlencode }}" >link</a>

how to stop a running script in Matlab

Consider having multiple matlab sessions. Keep the main session window (the pretty one with all the colours, file manager, command history, workspace, editor etc.) for running stuff that you know will terminate.

Stuff that you are experimenting with, say you are messing with ode suite and you get lots of warnings: matrix singular, because you altered some parameter and didn't predict what would happen, run in a separate session:

dos('matlab -automation -r &')

You can kill that without having to restart the whole of Matlab.

iPhone/iOS JSON parsing tutorial

As of iOS 5.0 Apple provides the NSJSONSerialization class "to convert JSON to Foundation objects and convert Foundation objects to JSON". No external frameworks to incorporate and according to benchmarks its performance is quite good, significantly better than SBJSON.

How to compare two strings are equal in value, what is the best method?

string1.equals(string2) is the way.

It returns true if string1 is equals to string2 in value. Else, it will return false.

equals reference

How to redirect back to form with input - Laravel 5

this will work definately !!!

  $v = Validator::make($request->all(),[
  'name' => ['Required','alpha']

     //this will return the errors & to check put "dd($errors);" in your blade(view)
     return back()->withErrors($v)->withInput();

background-size in shorthand background property (CSS3)

  1. Your jsfiddle uses background-image instead of background
  2. It seems to be a case of "not supported by this browser yet".

This works in Opera :
But it doesn't work in FF5 nor IE8. (yay for outdated browsers :D )

Code :

body {
  background:url( 400px 200px / 600px 400px no-repeat;

You could do it like this :

body {
    background:url( 400px 400px no-repeat;
    background-size:20px 20px

Which works in FF5 and Opera but not in IE8.

Appending an element to the end of a list in Scala

This is similar to one of the answers but in different way :

scala> val x = List(1,2,3)
x: List[Int] = List(1, 2, 3)

scala> val y = x ::: 4 :: Nil
y: List[Int] = List(1, 2, 3, 4)

Update query PHP MySQL

Need to add quote for that need to use dot operator:

mysql_query("UPDATE blogEntry SET content = '".$udcontent."', title = '".$udtitle."' WHERE id = '".$id."'");

Getting next element while cycling through a list

For strings list from 1(or whatever > 0) until end.

itens = ['car', 'house', 'moon', 'sun']

v = 0
for item in itens:
    b = itens[1 + v]
    print('any other command')
    if b == itens[-1]:
    v += 1

Creating a LinkedList class from scratch

What you have coded is not a LinkedList, at least not one that I recognize. For this assignment, you want to create two classes:


A LinkNode has one member field for the data it contains, and a LinkNode reference to the next LinkNode in the LinkedList. Yes, it's a self referential data structure. A LinkedList just has a special LinkNode reference that refers to the first item in the list.

When you add an item in the LinkedList, you traverse all the LinkNode's until you reach the last one. This LinkNode's next should be null. You then construct a new LinkNode here, set it's value, and add it to the LinkedList.

public class LinkNode { 

    String data;
    LinkNode next;

    public LinkNode(String item) { 

       data = item;



public class LinkedList { 

    LinkNode head;

    public LinkedList(String item) { 

       head = new LinkNode(item);


    public void add(String item) { 

       //pseudo code: while next isn't null, walk the list
       //once you reach the end, create a new LinkNode and add the item to it.  Then
       //set the last LinkNode's next to this new LinkNode



What is the simplest jQuery way to have a 'position:fixed' (always at top) div?

For those browsers that do support "position: fixed" you can simply use javascript (jQuery) to change the position to "fixed" when scrolling. This eliminates the jumpiness when scrolling with the $(window).scroll(function()) solutions listed here.

Ben Nadel demonstrates this in his tutorial: Creating A Sometimes-Fixed-Position Element With jQuery

AWS EFS vs EBS vs S3 (differences & when to use?)

EFS & S3 have the same purpose, you can store any kind of object or files.

But for me the only difference is EFS is allowing you to have a traditional file system in the VM(EC2) cloud with more flexibility like you can attach to multiple instances.

S3, on the other hand, is a separate flexible and elastic server for your objects. It can be used for your static files, images, videos or even hosting static app (js).

EBS is obviously for block storage where you can install OS or anything related to your OS.

C Program to find day of week given date

Not in one line of code, there's nothing for dealing with dates in the C standard library. It would be fairly simple to write a function based on the Doomsday algorithm, or similar, though.

iOS Safari – How to disable overscroll but allow scrollable divs to scroll normally?

I had surprising luck with with simple:

body {
    height: 100vh;

It works great to disable overscroll for pop-ups or menus and it doesn't force browser bars to appear like when using position:fixed. BUT - you need to save scroll position before setting fixed height and restore it when hiding the pop-up, otherwise, browser will scroll to top.

react hooks useEffect() cleanup for only componentWillUnmount?

instead of creating too many complicated functions and methods what I do is I create an event listener and automatically have mount and unmount done for me without having to worry about doing it manually. Here is an example.

useEffect( () => {

    window.addEventListener("load",  pageLoad);

    //component will unmount
    return () => {
        window.removeEventListener("load", pageLoad);


now that this part is done I just run anything I want from the pageLoad function like this.

const pageLoad = () =>{
console.log(I was mounted and unmounted automatically :D)}

overlay two images in android to set an imageview

this is my solution:

    public Bitmap Blend(Bitmap topImage1, Bitmap bottomImage1, PorterDuff.Mode Type) {

        Bitmap workingBitmap = Bitmap.createBitmap(topImage1);
        Bitmap topImage = workingBitmap.copy(Bitmap.Config.ARGB_8888, true);

        Bitmap workingBitmap2 = Bitmap.createBitmap(bottomImage1);
        Bitmap bottomImage = workingBitmap2.copy(Bitmap.Config.ARGB_8888, true);

        Rect dest = new Rect(0, 0, bottomImage.getWidth(), bottomImage.getHeight());
        new BitmapFactory.Options().inPreferredConfig = Bitmap.Config.ARGB_8888;
        Canvas canvas = new Canvas(bottomImage);
        Paint paint = new Paint();

        paint.setXfermode(new PorterDuffXfermode(Type));

        canvas.drawBitmap(topImage, null, dest, paint);
        return bottomImage;

usage :

imageView.setImageBitmap(Blend(topBitmap, bottomBitmap, PorterDuff.Mode.SCREEN));


imageView.setImageBitmap(Blend(topBitmap, bottomBitmap, PorterDuff.Mode.OVERLAY));

and the results :

Overlay mode : Overlay mode

Screen mode: Screen mode

How to plot a histogram using Matplotlib in Python with a list of data?

Though the question appears to be demanding plotting a histogram using matplotlib.hist() function, it can arguably be not done using the same as the latter part of the question demands to use the given probabilities as the y-values of bars and given names(strings) as the x-values.

I'm assuming a sample list of names corresponding to given probabilities to draw the plot. A simple bar plot serves the purpose here for the given problem. The following code can be used:

import matplotlib.pyplot as plt
probability = [0.3602150537634409, 0.42028985507246375, 
  0.373117033603708, 0.36813186813186816, 0.32517482517482516, 
  0.4175257731958763, 0.41025641025641024, 0.39408866995073893, 
  0.4143222506393862, 0.34, 0.391025641025641, 0.3130841121495327, 
names = ['name1', 'name2', 'name3', 'name4', 'name5', 'name6', 'name7', 'name8', 'name9',
'name10', 'name11', 'name12', 'name13'] #sample names, probability)
plt.yticks(probability) #This may be included or excluded as per need

Java8: HashMap<X, Y> to HashMap<X, Z> using Stream / Map-Reduce / Collector

If you don't mind using 3rd party libraries, my cyclops-react lib has extensions for all JDK Collection types, including Map. We can just transform the map directly using the 'map' operator (by default map acts on the values in the map).

   MapX<String,Integer> y = MapX.fromMap(HashMaps.of("hello","1"))

bimap can be used to transform the keys and values at the same time

  MapX<String,Integer> y = MapX.fromMap(HashMaps.of("hello","1"))

JavaScript: Create and save file

A very minor improvement of the code by Awesomeness01 (no need for anchor tag) with addition as suggested by trueimage (support for IE):

// Function to download data to a file
function download(data, filename, type) {
    var file = new Blob([data], {type: type});
    if (window.navigator.msSaveOrOpenBlob) // IE10+
        window.navigator.msSaveOrOpenBlob(file, filename);
    else { // Others
        var a = document.createElement("a"),
                url = URL.createObjectURL(file);
        a.href = url; = filename;
        setTimeout(function() {
        }, 0); 

Tested to be working properly in Chrome, FireFox and IE10.

In Safari, the data gets opened in a new tab and one would have to manually save this file.

How to get UTC timestamp in Ruby?

You could use:

Send POST request with JSON data using Volley

JsonObjectRequest actually accepts JSONObject as body.

From this blog article,

final String url = "some/url";
final JSONObject jsonBody = new JSONObject("{\"type\":\"example\"}");

new JsonObjectRequest(url, jsonBody, new Response.Listener<JSONObject>() { ... });

Here is the source code and JavaDoc (@param jsonRequest):

 * Creates a new request.
 * @param method the HTTP method to use
 * @param url URL to fetch the JSON from
 * @param jsonRequest A {@link JSONObject} to post with the request. Null is allowed and
 *   indicates no parameters will be posted along with request.
 * @param listener Listener to receive the JSON response
 * @param errorListener Error listener, or null to ignore errors.
public JsonObjectRequest(int method, String url, JSONObject jsonRequest,
        Listener<JSONObject> listener, ErrorListener errorListener) {
    super(method, url, (jsonRequest == null) ? null : jsonRequest.toString(), listener,

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

I do this:

Data.find( { $query: { user: req.user }, $orderby: { dateAdded: -1 } } function ( results ) {

This will show the most recent things first.

What does "The following object is masked from 'package:xxx'" mean?

I have the same problem. I avoid it with remove.packages("Package making this confusion") and it works. In my case, I don't need the second package, so that is not a very good idea.

get list of packages installed in Anaconda

To check if a specific package is installed:

conda list html5lib

which outputs something like this if installed:

# packages in environment at C:\ProgramData\Anaconda3:
# Name                    Version                   Build  Channel
html5lib                  1.0.1                    py37_0

or something like this if not installed:

# packages in environment at C:\ProgramData\Anaconda3:
# Name                    Version                   Build  Channel

you don't need to type the exact package name. Partial matches are supported:

conda list html

This outputs all installed packages containing 'html':

# packages in environment at C:\ProgramData\Anaconda3:
# Name                    Version                   Build  Channel
html5lib                  1.0.1                    py37_0
sphinxcontrib-htmlhelp    1.0.2                      py_0
sphinxcontrib-serializinghtml 1.1.3                      py_0

How to get a list of installed android applications and pick one to run

context.getPackageManager().getInstalledApplications(PackageManager.GET_META_DATA); Should return the list of all the installed apps but in android 11 it'll only return the list of system apps. To get the list of all the applications(system+user) we need to provide an additional permission to the application i.e

<uses-permission android:name"android.permission.QUERY_ALL_PACKAGES">

How to iterate (keys, values) in JavaScript?

The Object.entries() method has been specified in ES2017 (and is supported in all modern browsers):

for (const [ key, value ] of Object.entries(dictionary)) {
    // do something with `key` and `value`


  • Object.entries() takes an object like { a: 1, b: 2, c: 3 } and turns it into an array of key-value pairs: [ [ 'a', 1 ], [ 'b', 2 ], [ 'c', 3 ] ].

  • With for ... of we can loop over the entries of the so created array.

  • Since we are guaranteed that each of the so iterated array items is itself a two-entry array, we can use destructuring to directly assign variables key and value to its first and second item.

Converting file size in bytes to human-readable string

I wanted the "file manager" behavior (e.g., Windows Explorer) where the number of decimal places is proportional to the number size. Seemingly none of the other answers does this.

function humanFileSize(size) {
    if (size < 1024) return size + ' B'
    let i = Math.floor(Math.log(size) / Math.log(1024))
    let num = (size / Math.pow(1024, i))
    let round = Math.round(num)
    num = round < 10 ? num.toFixed(2) : round < 100 ? num.toFixed(1) : round
    return `${num} ${'KMGTPEZY'[i-1]}B`

Here's some examples:

humanFileSize(0)          // "0 B"
humanFileSize(1023)       // "1023 B"
humanFileSize(1024)       // "1.00 KB"
humanFileSize(10240)      // "10.0 KB"
humanFileSize(102400)     // "100 KB"
humanFileSize(1024000)    // "1000 KB"
humanFileSize(12345678)   // "11.8 MB"
humanFileSize(1234567890) // "1.15 GB"

Int division: Why is the result of 1/3 == 0?

I did this.

double g = 1.0/3.0;
System.out.printf("%gf", g);

Use .0 while doing double calculations or else Java will assume you are using Integers. If a Calculation uses any amount of double values, then the output will be a double value. If the are all Integers, then the output will be an Integer.

SharePoint : How can I programmatically add items to a custom list instance

I think these both blog post should help you solving your problem.

Short walk through:

  1. Get a instance of the list you want to add the item to.
  2. Add a new item to the list:

    SPListItem newItem = list.AddItem();
  3. To bind you new item to a content type you have to set the content type id for the new item:

    newItem["ContentTypeId"] = <Id of the content type>;
  4. Set the fields specified within your content type.

  5. Commit your changes:


Routing with multiple Get methods in ASP.NET Web API

There are lots of good answers already for this question. However nowadays Route configuration is sort of "deprecated". The newer version of MVC (.NET Core) does not support it. So better to get use to it :)

So I agree with all the answers which uses Attribute style routing. But I keep noticing that everyone repeated the base part of the route (api/...). It is better to apply a [RoutePrefix] attribute on top of the Controller class and don't repeat the same string over and over again.

public class MyController : Controller
 public List<Customer> Get()
   //gets all customer logic

 public List<Customer> GetCustomerByCurrentMonth()
     //gets some customer 

 public Customer GetCustomerById(string id)
  //gets a single customer by specified id
 public Customer GetCustomerByUsername(string username)
    //gets customer by its username

c# dictionary How to add multiple values for single key?

If I understood what you want:

dictionary.Add("key", new List<string>()); 


dictionary["key"].Add("string to your list");

How to manually set an authenticated user in Spring Security / SpringMVC

Ultimately figured out the root of the problem.

When I create the security context manually no session object is created. Only when the request finishes processing does the Spring Security mechanism realize that the session object is null (when it tries to store the security context to the session after the request has been processed).

At the end of the request Spring Security creates a new session object and session ID. However this new session ID never makes it to the browser because it occurs at the end of the request, after the response to the browser has been made. This causes the new session ID (and hence the Security context containing my manually logged on user) to be lost when the next request contains the previous session ID.

EOFError: end of file reached issue with Net::HTTP

In Ruby on Rails I used this code, and it works perfectly:

req_profilepic = ActiveSupport::JSON.decode(open(URI.encode("{fb_access_token}")))

profilepic_url = req_profilepic['picture']

GitHub: invalid username or password

That problem happens sometimes due to wrong password. Please check if you are linked with AD password (Active Directory Password) and you recently changed you AD password but still trying git command with old password or not.

Update old AD password

Control Panel > Credential Manager > Windows Credential > change github password with my new AD password

number several equations with only one number

First of all, you probably don't want the align environment if you have only one column of equations. In fact, your example is probably best with the cases environment. But to answer your question directly, used the aligned environment within equation - this way the outside environment gives the number:

  w^T x_i + b &\geq 1-\xi_i &\text{ if }& y_i=1,  \\
  w^T x_i + b &\leq -1+\xi_i & \text{ if } &y_i=-1,

The documentation of the amsmath package explains this and more.

Set session variable in laravel

To add to the above answers, ensure you define your function like this:

public function functionName(Request $request)  {

Note the "(Request $request)", now set a session like this:

$request->session()->put('key', 'value');

And retrieve the session in this way:

$data = $request->session()->get('key');

To erase the session try this:




const vs constexpr on variables

I believe there is a difference. Let's rename them so that we can talk about them more easily:

const     double PI1 = 3.141592653589793;
constexpr double PI2 = 3.141592653589793;

Both PI1 and PI2 are constant, meaning you can not modify them. However only PI2 is a compile-time constant. It shall be initialized at compile time. PI1 may be initialized at compile time or run time. Furthermore, only PI2 can be used in a context that requires a compile-time constant. For example:

constexpr double PI3 = PI1;  // error


constexpr double PI3 = PI2;  // ok


static_assert(PI1 == 3.141592653589793, "");  // error


static_assert(PI2 == 3.141592653589793, "");  // ok

As to which you should use? Use whichever meets your needs. Do you want to ensure that you have a compile time constant that can be used in contexts where a compile-time constant is required? Do you want to be able to initialize it with a computation done at run time? Etc.

Automating the InvokeRequired code pattern

Create a ThreadSafeInvoke.snippet file, and then you can just select the update statements, right click and select 'Surround With...' or Ctrl-K+S:

<?xml version="1.0" encoding="utf-8" ?>
<CodeSnippet Format="1.0.0" xmlns="">
    <Description>Wraps code in an anonymous method passed to Invoke for Thread safety.</Description>
    <Code Language="CSharp">
      Invoke( (MethodInvoker) delegate

Convert RGB to Black & White in OpenCV

A simple way of "binarize" an image is to compare to a threshold: For example you can compare all elements in a matrix against a value with opencv in c++

cv::Mat img = cv::imread("image.jpg", CV_LOAD_IMAGE_GRAYSCALE); 
cv::Mat bw = img > 128;

In this way, all pixels in the matrix greater than 128 now are white, and these less than 128 or equals will be black

Optionally, and for me gave good results is to apply blur

cv::blur( bw, bw, cv::Size(3,3) );

Later you can save it as said before with:

cv::imwrite("image_bw.jpg", bw);

col align right

For The Bootstrap 4+

This Code Worked Well for me

<div class="row">
        <div class="col">
            <div class="ml-auto">
                this content will be in the Right
        <div class="col mr-auto">
            <div class="mr-auto">
                this content will be in the leftt

Dynamically Add Variable Name Value Pairs to JSON Object

when using javascript objects, you can also just use "dot notation" to add an item, (which JSLint prefers)

var myArray = { name : "john" };
//will initiate a key-value array with one item "name" and the value "john"
myArray.lastName = "smith";
//will add a key named lastName with the value "smith"
//Object {name: "john", lastName: "smith"}

Here is a screenshot from testing in the Chrome console


What is HTTP "Host" header?

The Host Header tells the webserver which virtual host to use (if set up). You can even have the same virtual host using several aliases (= domains and wildcard-domains). In this case, you still have the possibility to read that header manually in your web app if you want to provide different behavior based on different domains addressed. This is possible because in your webserver you can (and if I'm not mistaken you must) set up one vhost to be the default host. This default vhost is used whenever the host header does not match any of the configured virtual hosts.

That means: You get it right, although saying "multiple hosts" may be somewhat misleading: The host (the addressed machine) is the same, what really gets resolved to the IP address are different domain names (including subdomains) that are also referred to as hostnames (but not hosts!).

Although not part of the question, a fun fact: This specification led to problems with SSL in early days because the web server has to deliver the certificate that corresponds to the domain the client has addressed. However, in order to know what certificate to use, the webserver should have known the addressed hostname in advance. But because the client sends that information only over the encrypted channel (which means: after the certificate has already been sent), the server had to assume you browsed the default host. That meant one ssl-secured domain per IP address / port-combination.

This has been overcome with Server Name Indication; however, that again breaks some privacy, as the server name is now transferred in plain text again, so every man-in-the-middle would see which hostname you are trying to connect to.

Although the webserver would know the hostname from Server Name Indication, the Host header is not obsolete, because the Server Name Indication information is only used within the TLS handshake. With an unsecured connection, there is no Server Name Indication at all, so the Host header is still valid (and necessary).

Another fun fact: Most webservers (if not all) reject your HTTP request if it does not contain exactly one Host header, even if it could be omitted because there is only the default vhost configured. That means the minimum required information in an http-(get-)request is the first line containing METHOD RESOURCE and PROTOCOL VERSION and at least the Host header, like this:

GET /someresource.html HTTP/1.1

In the MDN Documentation on the "Host" header they actually phrase it like this:

A Host header field must be sent in all HTTP/1.1 request messages. A 400 (Bad Request) status code will be sent to any HTTP/1.1 request message that lacks a Host header field or contains more than one.

As mentioned by Darrel Miller, the complete specs can be found in RFC7230.

Can I underline text in an Android layout?

In Kotlin extension function can be used. This can only be used from code, not xml.

fun TextView.underline() {
    paintFlags = paintFlags or Paint.UNDERLINE_TEXT_FLAG



Why doesn't JavaScript support multithreading?

Do you mean why doesn't the language support multithreading or why don't JavaScript engines in browsers support multithreading?

The answer to the first question is that JavaScript in the browser is meant to be run in a sandbox and in a machine/OS-independent way, to add multithreading support would complicate the language and tie the language too closely to the OS.

How do I list all loaded assemblies?

Here's what I ended up with. It's a listing of all properties and methods, and I listed all parameters for each method. I didn't succeed on getting all of the values.

foreach(System.Reflection.AssemblyName an in System.Reflection.Assembly.GetExecutingAssembly().GetReferencedAssemblies()){                      
            System.Reflection.Assembly asm = System.Reflection.Assembly.Load(an.ToString());
            foreach(Type type in asm.GetTypes()){   
                foreach (System.Reflection.PropertyInfo property in type.GetProperties()){
                    if (property.CanRead){
                        Response.Write("<br>" + an.ToString() + "." + type.ToString() + "." + property.Name);       
                var methods = type.GetMethods();
                foreach (System.Reflection.MethodInfo method in methods){               
                    Response.Write("<br><b>" + an.ToString() + "."  + type.ToString() + "." + method.Name  + "</b>");   
                    foreach (System.Reflection.ParameterInfo param in method.GetParameters())
                        Response.Write("<br><i>Param=" + param.Name.ToString());
                        Response.Write("<br>  Type=" + param.ParameterType.ToString());
                        Response.Write("<br>  Position=" + param.Position.ToString());
                        Response.Write("<br>  Optional=" + param.IsOptional.ToString() + "</i>");

Node.js console.log() not logging anything

Using modern --inspect with node the console.log is captured and relayed to the browser.

node --inspect myApp.js

or to capture early logging --inspect-brk can be used to stop the program on the first line of the first module...

node --inspect-brk myApp.js

Bootstrap 4: Multilevel Dropdown Inside Navigation

The following is MultiLevel dropdown based on bootstrap4. I tried it was according to the bootstrap4 basic dropdown.

    position: relative;_x000D_
.dropdown-submenu a::after{_x000D_
    transform: rotate(-90deg);_x000D_
    position: absolute;_x000D_
    right: 3px;_x000D_
    top: 40%;_x000D_
.dropdown-submenu:hover .dropdown-menu, .dropdown-submenu:focus .dropdown-menu{_x000D_
    display: flex;_x000D_
    flex-direction: column;_x000D_
    position: absolute !important;_x000D_
    margin-top: -30px;_x000D_
    left: 100%;_x000D_
@media (max-width: 992px) {_x000D_
        width: 50%;_x000D_
    .dropdown-menu .dropdown-submenu{_x000D_
        width: auto;_x000D_
<link rel="stylesheet" href="" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous">_x000D_
<script src="" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"></script>_x000D_
<script src="" integrity="sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb" crossorigin="anonymous"></script>_x000D_
<script src="" integrity="sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn" crossorigin="anonymous"></script>_x000D_
<nav class="navbar navbar-toggleable-md navbar-light bg-faded">_x000D_
  <button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">_x000D_
    <span class="navbar-toggler-icon"></span>_x000D_
  <a class="navbar-brand" href="#">Navbar</a>_x000D_
  <div class="collapse navbar-collapse" id="navbarNavDropdown">_x000D_
    <ul class="navbar-nav mr-auto">_x000D_
      <li class="nav-item active">_x000D_
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>_x000D_
      <li class="nav-item">_x000D_
        <a class="nav-link" href="#">Link 1</a>_x000D_
      <li class="nav-item dropdown">_x000D_
        <a class="nav-link dropdown-toggle" href="" id="navbarDropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">_x000D_
          Dropdown link_x000D_
        <ul class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">_x000D_
          <li><a class="dropdown-item" href="#">Action</a></li>_x000D_
          <li><a class="dropdown-item" href="#">Another action</a></li>_x000D_
          <li class="dropdown-submenu"><a class="dropdown-item dropdown-toggle" data-toggle="dropdown" href="#">Something else here</a>_x000D_
            <ul class="dropdown-menu">_x000D_
              <a class="dropdown-item" href="#">A</a>_x000D_
              <a class="dropdown-item" href="#">b</a>_x000D_

Change the image source on rollover using jQuery

<img src="img1.jpg" data-swap="img2.jpg"/>

img = {

 init: function() {
  $('img').on('mouseover', img.swap);
  $('img').on('mouseover', img.swap);

 swap: function() {
  var tmp = $(this).data('swap');
  $(this).attr('data-swap', $(this).attr('src'));
  $(this).attr('str', tmp);


Can Mockito stub a method without regard to the argument?


or (to avoid nulls):


Don't forget to import matchers (many others are available):

For Mockito 2.1.0 and newer:

import static org.mockito.ArgumentMatchers.*;

For older versions:

import static org.mockito.Matchers.*;

How to use pip with Python 3.x alongside Python 2.x

Thought this is old question, I think I have better solution

  1. To use pip for a python 2.x environment, use this command -

    py -2 -m pip install -r requirements.txt

  2. To use pip for python 3.x environment, use this command -

    py -3 -m pip install -r requirements.txt

wget/curl large file from google drive

You just need to use wget with:[your ID without brackets]&export=download

PD. The file must be public.

Detect browser or tab closing

For similar tasks, you can use sessionStorage to store data locally until the browser tab is closed.

The sessionStorage object stores data for only one session (the data is deleted when the browser tab is closed).(W3Schools)

This is my pen.

<div id="Notice">
    <span title="remove this until browser tab is closed"><u>dismiss</u>.</span>
    $("#Notice").click(function() {
     //set sessionStorage on click
        sessionStorage.setItem("dismissNotice", "Hello");
    if (sessionStorage.getItem("dismissNotice"))
    //When sessionStorage is set Do stuff...

How do I download a package from apt-get without installing it?

Don't forget the option "-o", which lets you download anywhere you want, although you have to create "archives", "lock" and "partial" first (the command prints what's needed).

apt-get install -d -o=dir::cache=/tmp whateveryouwant

What is a regular expression for a MAC Address?


bootstrap datepicker today as default

Set after Init

 $('#dp-ex-3').datepicker({ autoclose: true, language: 'es' });
$('#dp-ex-3').datepicker('update', new Date());

This example is working.

How to allocate aligned memory only using the standard library?

You can also add some 16 bytes and then push the original ptr to 16bit aligned by adding the (16-mod) as below the pointer :

void *mem1 = malloc(1024+16);
void *mem = ((char*)mem1)+1; // force misalign ( my computer always aligns)
printf ( " ptr = %p \n ", mem );
void *ptr = ((long)mem+16) & ~ 0x0F;
printf ( " aligned ptr = %p \n ", ptr );

printf (" ptr after adding diff mod %p (same as above ) ", (long)mem1 + (16 -((long)mem1%16)) );


jQuery: How to get to a particular child of a parent?

Calling .parents(".box .something1") will return all parent elements that match the selector .box .something. In other words, it will return parent elements that are .something1 and are inside of .box.

You need to get the children of the closest parent, like this:


This code calls .closest to get the innermost parent matching a selector, then calls .children on that parent element to find the uncle you're looking for.

Print multiple arguments in Python

Use: .format():

print("Total score for {0} is {1}".format(name, score))


// Recommended, more readable code

print("Total score for {n} is {s}".format(n=name, s=score))


print("Total score for" + name + " is " + score)


`print("Total score for %s is %d" % (name, score))`

How to make an inline element appear on new line, or block element not occupy the whole line?

Even though the question is quite fuzzy and the HTML snippet is quite limited, I suppose

.feature_desc {
    display: block;
.feature_desc:before {
    content: "";
    display: block;

might give you want you want to achieve without the <br/> element. Though it would help to see your CSS applied to these elements.

NOTE. The example above doesn't work in IE7 though.

Java HTTPS client certificate authentication

Maven pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="" xmlns:xsi="" xsi:schemaLocation="">

Java code:

package some.examples;

import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.ssl.SSLContexts;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.apache.http.entity.InputStreamEntity;

public class SSLCliAuthExample {

private static final Logger LOG = Logger.getLogger(SSLCliAuthExample.class.getName());

private static final String CA_KEYSTORE_TYPE = KeyStore.getDefaultType(); //"JKS";
private static final String CA_KEYSTORE_PATH = "./cacert.jks";
private static final String CA_KEYSTORE_PASS = "changeit";

private static final String CLIENT_KEYSTORE_TYPE = "PKCS12";
private static final String CLIENT_KEYSTORE_PATH = "./client.p12";
private static final String CLIENT_KEYSTORE_PASS = "changeit";

public static void main(String[] args) throws Exception {

public final static void requestTimestamp() throws Exception {
    SSLConnectionSocketFactory csf = new SSLConnectionSocketFactory(
            new String[]{"TLSv1"}, // Allow TLSv1 protocol only
    try (CloseableHttpClient httpclient = HttpClients.custom().setSSLSocketFactory(csf).build()) {
        HttpPost req = new HttpPost("");
        HttpEntity ent = new InputStreamEntity(new FileInputStream("./bytes.bin"));
        try (CloseableHttpResponse response = httpclient.execute(req)) {
            HttpEntity entity = response.getEntity();
            LOG.log(Level.INFO, "*** Reponse status: {0}", response.getStatusLine());
            LOG.log(Level.INFO, "*** Response entity: {0}", entity.toString());

public static RequestConfig configureRequest() {
    HttpHost proxy = new HttpHost("changeit.local", 8080, "http");
    RequestConfig config = RequestConfig.custom()
    return config;

public static SSLContext createSslCustomContext() throws KeyStoreException, IOException, NoSuchAlgorithmException, CertificateException, KeyManagementException, UnrecoverableKeyException {
    // Trusted CA keystore
    KeyStore tks = KeyStore.getInstance(CA_KEYSTORE_TYPE);
    tks.load(new FileInputStream(CA_KEYSTORE_PATH), CA_KEYSTORE_PASS.toCharArray());

    // Client keystore
    KeyStore cks = KeyStore.getInstance(CLIENT_KEYSTORE_TYPE);
    cks.load(new FileInputStream(CLIENT_KEYSTORE_PATH), CLIENT_KEYSTORE_PASS.toCharArray());

    SSLContext sslcontext = SSLContexts.custom()
            //.loadTrustMaterial(tks, new TrustSelfSignedStrategy()) // use it to customize
            .loadKeyMaterial(cks, CLIENT_KEYSTORE_PASS.toCharArray()) // load client certificate
    return sslcontext;


Installing jQuery?

Well, as most of the answers pointed out, you can include the jQuery file locally as well as use Google's CDN/Microsoft CDN servers. On choosing Google vs. Microsoft CDN go Google_CDN vs. Microsoft_CDN depending on your requirement.

Generally for intranet applications include jQuery file locally and never use the CDN method since for intranet, the LAN is 10x times faster than Internet. For Internet and public facing applications use a hybrid approach as suggested by cowgod elsewhere. Also don't forget to use the nice tool JS_Compressor to compress the extra JavaScript code you add to your jQuery library. It makes JavaScript really fast.

Call web service in excel

Yes You Can!

I worked on a project that did that (see comment). Unfortunately no code samples from that one, but googling revealed these:

How you can integrate data from several Web services using Excel and VBA

STEP BY STEP: Consuming Web Services through VBA (Excel or Word)

VBA: Consume Soap Web Services

How to fire AJAX request Periodically?

You can use setTimeout or setInterval.

The difference is - setTimeout triggers your function only once, and then you must set it again. setInterval keeps triggering expression again and again, unless you tell it to stop

How to manage exceptions thrown in filters in Spring?

I come across this issue myself and I performed the steps below to reuse my ExceptionController that is annotated with @ControllerAdvise for Exceptions thrown in a registered Filter.

There are obviously many ways to handle exception but, in my case, I wanted the exception to be handled by my ExceptionController because I am stubborn and also because I don't want to copy/paste the same code (i.e. I have some processing/logging code in ExceptionController). I would like to return the beautiful JSON response just like the rest of the exceptions thrown not from a Filter.

  "status": 400,
  "message": "some exception thrown when executing the request"

Anyway, I managed to make use of my ExceptionHandler and I had to do a little bit of extra as shown below in steps:


  1. You have a custom filter that may or may not throw an exception
  2. You have a Spring controller that handles exceptions using @ControllerAdvise i.e. MyExceptionController

Sample code

//sample Filter, to be added in web.xml
public MyFilterThatThrowException implements Filter {
   //Spring Controller annotated with @ControllerAdvise which has handlers
   //for exceptions
   private MyExceptionController myExceptionController; 

   public void destroy() {
        // TODO Auto-generated method stub

   public void init(FilterConfig arg0) throws ServletException {
       //Manually get an instance of MyExceptionController
       ApplicationContext ctx = WebApplicationContextUtils

       //MyExceptionHanlder is now accessible because I loaded it manually
       this.myExceptionController = ctx.getBean(MyExceptionController.class); 

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse res = (HttpServletResponse) response;

        try {
           //code that throws exception
        } catch(Exception ex) {
          //MyObject is whatever the output of the below method
          MyObject errorDTO = myExceptionController.handleMyException(req, ex); 

          //set the response object
          res.setStatus(errorDTO .getStatus());

          //pass down the actual obj that exception handler normally send
          ObjectMapper mapper = new ObjectMapper();
          PrintWriter out = res.getWriter(); 
          out.print(mapper.writeValueAsString(errorDTO ));


        //proceed normally otherwise
        chain.doFilter(request, response); 

And now the sample Spring Controller that handles Exception in normal cases (i.e. exceptions that are not usually thrown in Filter level, the one we want to use for exceptions thrown in a Filter)

//sample SpringController 
public class ExceptionController extends ResponseEntityExceptionHandler {

    //sample handler
    @ResponseStatus(value = HttpStatus.BAD_REQUEST)
    public @ResponseBody MyObject handleSQLException(HttpServletRequest request,
            Exception ex){
        ErrorDTO response = new ErrorDTO (400, "some exception thrown when "
                + "executing the request."); 
        return response;
    //other handlers

Sharing the solution with those who wish to use ExceptionController for Exceptions thrown in a Filter.

Executing JavaScript after X seconds

setTimeout will help you to execute any JavaScript code based on the time you set.


setTimeout(code, millisec, lang)


setTimeout("function1()", 1000);

For more details, see

Excel: macro to export worksheet as CSV file without leaving my current Excel sheet

As per my comment on @neves post, I slightly improved this by adding the xlPasteFormats as well as values part so dates go across as dates - I mostly save as CSV for bank statements, so needed dates.

Sub ExportAsCSV()

    Dim MyFileName As String
    Dim CurrentWB As Workbook, TempWB As Workbook

    Set CurrentWB = ActiveWorkbook

    Set TempWB = Application.Workbooks.Add(1)
    With TempWB.Sheets(1).Range("A1")
        .PasteSpecial xlPasteValues
        .PasteSpecial xlPasteFormats
    End With

    'Dim Change below to "- 4"  to become compatible with .xls files
    MyFileName = CurrentWB.Path & "\" & Left(CurrentWB.Name, Len(CurrentWB.Name) - 5) & ".csv"

    Application.DisplayAlerts = False
    TempWB.SaveAs Filename:=MyFileName, FileFormat:=xlCSV, CreateBackup:=False, Local:=True
    TempWB.Close SaveChanges:=False
    Application.DisplayAlerts = True
End Sub

Convert a Pandas DataFrame to a dictionary

The to_dict() method sets the column names as dictionary keys so you'll need to reshape your DataFrame slightly. Setting the 'ID' column as the index and then transposing the DataFrame is one way to achieve this.

to_dict() also accepts an 'orient' argument which you'll need in order to output a list of values for each column. Otherwise, a dictionary of the form {index: value} will be returned for each column.

These steps can be done with the following line:

>>> df.set_index('ID').T.to_dict('list')
{'p': [1, 3, 2], 'q': [4, 3, 2], 'r': [4, 0, 9]}

In case a different dictionary format is needed, here are examples of the possible orient arguments. Consider the following simple DataFrame:

>>> df = pd.DataFrame({'a': ['red', 'yellow', 'blue'], 'b': [0.5, 0.25, 0.125]})
>>> df
        a      b
0     red  0.500
1  yellow  0.250
2    blue  0.125

Then the options are as follows.

dict - the default: column names are keys, values are dictionaries of index:data pairs

>>> df.to_dict('dict')
{'a': {0: 'red', 1: 'yellow', 2: 'blue'}, 
 'b': {0: 0.5, 1: 0.25, 2: 0.125}}

list - keys are column names, values are lists of column data

>>> df.to_dict('list')
{'a': ['red', 'yellow', 'blue'], 
 'b': [0.5, 0.25, 0.125]}

series - like 'list', but values are Series

>>> df.to_dict('series')
{'a': 0       red
      1    yellow
      2      blue
      Name: a, dtype: object, 

 'b': 0    0.500
      1    0.250
      2    0.125
      Name: b, dtype: float64}

split - splits columns/data/index as keys with values being column names, data values by row and index labels respectively

>>> df.to_dict('split')
{'columns': ['a', 'b'],
 'data': [['red', 0.5], ['yellow', 0.25], ['blue', 0.125]],
 'index': [0, 1, 2]}

records - each row becomes a dictionary where key is column name and value is the data in the cell

>>> df.to_dict('records')
[{'a': 'red', 'b': 0.5}, 
 {'a': 'yellow', 'b': 0.25}, 
 {'a': 'blue', 'b': 0.125}]

index - like 'records', but a dictionary of dictionaries with keys as index labels (rather than a list)

>>> df.to_dict('index')
{0: {'a': 'red', 'b': 0.5},
 1: {'a': 'yellow', 'b': 0.25},
 2: {'a': 'blue', 'b': 0.125}}

How to check what user php is running as?


A tad late, but even though the following is a work-around, it solves the requirement as this works just fine:

    function get_sys_usr()
        $unique_name = uniqid();  // not-so-unique id
        $native_path = "./temp/$unique_name.php";
        $public_path = "$unique_name.php";
        $php_content = "<? echo get_current_user(); ?>";
        $process_usr = "apache";  // fall-back

        if (is_readable("./temp") && is_writable("./temp"))
            $process_usr = trim(file_get_contents($public_path));

        return $process_usr;

    echo get_sys_usr();  // www-data


The code-highlighting above is not accurate, please copy & paste in your favorite editor and view as PHP code, or save and test it yourself.

As you probably know, get_current_user() returns the owner of the "current running script" - so if you did not "chown" a script on the server to the web-server-user it will most probably be "nobody", or if the developer-user exists on the same OS, it will rather display that username.

To work around this, we create a file with the current running process. If you just require() this into the current running script, it will return the same as the parent-script as mentioned; so, we need to run it as a separate request to take effect.


In order to make this effective, consider running a design pattern that incorporates "runtime-mode", so when the server is in "development-mode or test-mode" then only it could run this function and save its output somewhere in an include, -or just plain text or database, or whichever.

Of course you can change some particulars of the code above as you wish to make it more dynamic, but the logic is as follows:

  • define a unique reference to limit interference with other users
  • define a local file-path for writing a temporary file
  • define a public url/path to run this file in its own process
  • write the temporary php file that outputs the script owner name
  • get the output of this script by making a request to it
  • delete the file as it is no longer needed - or leave it if you want
  • return the output of the request as return-value of the function

ThreeJS: Remove object from scene

I think seeing your usage for addEntity and removeEntity code would be helpful, but my first thought is are you actually setting the Try in your loader just before scene.add(object); something like this: = "test_name";

What might be happening is the default "name" for an Object3D is "", so when you then call your removeEntity function it fails due to the scene objects name being ""

Also, I notice you pass in to your loader? Is this where your storing the URL to the resource? If so, I would recommend using the Object3D's built in .userData method to store that information and keep the name field for scene identification purposes.

Edit: Response to newly added Code

First thing to note is it's not a great idea to have "/" in your object name, it seems to work fine but you never know if some algorithm will decide to escape that string and break your project.

Second item is now that I've seen your code, its actually straight forward whats going on. Your delete function is trying to delete by name, you need an Object3D to delete. Try this:

function removeEntity(object) {
    var selectedObject = scene.getObjectByName(;
    scene.remove( selectedObject );

Here you see I lookup your Object3D in the Three.js Scene by passing in your object tag's name attribute. Hope that helps

Windows service start failure: Cannot start service from the command line or debugger

Your code has nothing to do with the service installation, it is not the problem.

In order to test the service, you must install it as indicated.

For more information about installing your service : Installing and Uninstalling Services

SQL get the last date time record


Will return one result with the latest date.

SELECT * FROM foo WHERE foo.Dates = (SELECT MAX(Dates) FROM foo)

Will return all results that have the same maximum date, to the milissecond.

This is for SQL Server. I'll leave it up to you to use the DATEPART function if you want to use dates but not times.

How can I check if a string is a number?

string str = "123";
int i = Int.Parse(str);

If str is a valid integer string then it will be converted to integer and stored in i other wise Exception occur.

How to detect a loop in a linked list?

Tortoise and hare

Take a look at Pollard's rho algorithm. It's not quite the same problem, but maybe you'll understand the logic from it, and apply it for linked lists.

(if you're lazy, you can just check out cycle detection -- check the part about the tortoise and hare.)

This only requires linear time, and 2 extra pointers.

In Java:

boolean hasLoop( Node first ) {
    if ( first == null ) return false;

    Node turtle = first;
    Node hare = first;

    while ( != null && != null ) {
         turtle =;
         hare =;

         if ( turtle == hare ) return true;

    return false;

(Most of the solution do not check for both next and for nulls. Also, since the turtle is always behind, you don't have to check it for null -- the hare did that already.)

Command line to remove an environment variable from the OS level configuration

I agree with CupawnTae.

SET is not useful for changes to the master environment.

FYI: System variables are in HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment (a good deal longer than user vars).

The full command for a system var named FOOBAR therefore is:

REG delete "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /F /V FOOBAR

(Note the quotes required to handle the space.)

It is too bad the setx command doesn't support a delete syntax. :(

PS: Use responsibly - If you kill your path variable, don't blame me!

Regarding C++ Include another class

The thing with compiling two .cpp files at the same time, it doesnt't mean they "know" about eachother. You will have to create a file, the "tells" your File1.cpp, there actually are functions and classes like ClassTwo. This file is called header-file and often doesn't include any executable code. (There are exception, e.g. for inline functions, but forget them at first) They serve a declarative need, just for telling, which functions are available.

When you have your File2.cpp and include it into your File1.cpp, you see a small problem: There is the same code twice: One in the File1.cpp and one in it's origin, File2.cpp.

Therefore you should create a header file, like File1.hpp or File1.h (other names are possible, but this is simply standard). It works like the following:


void SomeFunc(char c) //Definition aka Implementation
//do some stuff


void SomeFunc(char c); //Declaration aka Prototype

And for a matter of clean code you might add the following to the top of File1.cpp:

#include "File1.hpp"

And the following, surrounding File1.hpp's code:

//All your declarative code

This makes your header-file cleaner, regarding to duplicate code.

Duplicate line in Visual Studio Code

Search for copyLinesDownAction or copyLinesUpAction in your keyboard shortcuts

Usually, it is SHIFT+ALT+?

Implementing a HashMap in C

The primary goal of a hashmap is to store a data set and provide near constant time lookups on it using a unique key. There are two common styles of hashmap implementation:

  • Separate chaining: one with an array of buckets (linked lists)
  • Open addressing: a single array allocated with extra space so index collisions may be resolved by placing the entry in an adjacent slot.

Separate chaining is preferable if the hashmap may have a poor hash function, it is not desirable to pre-allocate storage for potentially unused slots, or entries may have variable size. This type of hashmap may continue to function relatively efficiently even when the load factor exceeds 1.0. Obviously, there is extra memory required in each entry to store linked list pointers.

Hashmaps using open addressing have potential performance advantages when the load factor is kept below a certain threshold (generally about 0.7) and a reasonably good hash function is used. This is because they avoid potential cache misses and many small memory allocations associated with a linked list, and perform all operations in a contiguous, pre-allocated array. Iteration through all elements is also cheaper. The catch is hashmaps using open addressing must be reallocated to a larger size and rehashed to maintain an ideal load factor, or they face a significant performance penalty. It is impossible for their load factor to exceed 1.0.

Some key performance metrics to evaluate when creating a hashmap would include:

  • Maximum load factor
  • Average collision count on insertion
  • Distribution of collisions: uneven distribution (clustering) could indicate a poor hash function.
  • Relative time for various operations: put, get, remove of existing and non-existing entries.

Here is a flexible hashmap implementation I made. I used open addressing and linear probing for collision resolution.

Import .bak file to a database in SQL server

.bak files are database backups. You can restore the backup with the method below:

How to: Restore a Database Backup (SQL Server Management Studio)

How to give ASP.NET access to a private key in a certificate in the certificate store?

For me, it was nothing more than re-importing the certificate with "Allow private key to be exported" checked.

I guess it is necessary, but it does make me nervous as it is a third party app accessing this certificate.

Checking to see if one array's elements are in another array in PHP

Performance test for in_array vs array_intersect:

$a1 = array(2,4,8,11,12,13,14,15,16,17,18,19,20);

$a2 = array(3,20);

$intersect_times = array();
$in_array_times = array();
for($j = 0; $j < 10; $j++)
    /***** TEST ONE array_intersect *******/
    $t = microtime(true);
    for($i = 0; $i < 100000; $i++)
        $x = array_intersect($a1,$a2);
        $x = empty($x);
    $intersect_times[] = microtime(true) - $t;

    /***** TEST TWO in_array *******/
    $t2 = microtime(true);
    for($i = 0; $i < 100000; $i++)
        $x = false;
        foreach($a2 as $v){
                $x = true;
    $in_array_times[] = microtime(true) - $t2;

echo '<hr><br>'.implode('<br>',$intersect_times).'<br>array_intersect avg: '.(array_sum($intersect_times) / count($intersect_times));
echo '<hr><br>'.implode('<br>',$in_array_times).'<br>in_array avg: '.(array_sum($in_array_times) / count($in_array_times));

Here are the results:

array_intersect avg: 0.16692011356354

in_array avg: 0.029640197753906

in_array is at least 5 times faster. Note that we "break" as soon as a result is found.

Android on-screen keyboard auto popping up

If you are using fragments, you need to call hideKeyboard every time in onResume and onCreate if you want to hide the keyboard.

    public void onResume() {
        Log.d(TAG, "SectionMyFragment onResume");

private void hideKeyboard() {
    if (getActivity() != null) {
        InputMethodManager inputMethodManager = (InputMethodManager)

        if (inputMethodManager != null) {
            if (getActivity().getCurrentFocus() != null) {
                Log.d(TAG, "hideSoftInputFromWindow 1");
                inputMethodManager.hideSoftInputFromWindow((getActivity().getCurrentFocus()).getWindowToken(), 0);

Does mobile Google Chrome support browser extensions?

I imagine that there are not many browsers supporting extension. Indeed, I have been interested in this question for the last year and I only found Dolphin supporting add-ons and other cool features announced few days ago. I want to test it soon.

Copy-item Files in Folders and subfolders in the same directory structure of source server using PowerShell

I had trouble with the most popular answer (overthinking). It put AFolder in the \Server\MyFolder\AFolder and I wanted the contents of AFolder and below in MyFolder. This didn't work.

Copy-Item -Verbose -Path C:\MyFolder\AFolder -Destination \\Server\MyFolder -recurse -Force

Plus I needed to Filter and only copy *.config files.

This didn't work, with "\*" because it did not recurse

Copy-Item -Verbose -Path C:\MyFolder\AFolder\* -Filter *.config -Destination \\Server\MyFolder -recurse -Force

I ended up lopping off the beginning of the path string, to get the childPath relative to where I was recursing from. This works for the use-case in question and went down many subdirectories, which some other solutions do not.

Get-Childitem -Path "$($sourcePath)/**/*.config" -Recurse | 
ForEach-Object {
  $childPath = "$_".substring($sourcePath.length+1)
  $dest = "$($destPath)\$($childPath)" #this puts a \ between dest and child path
  Copy-Item -Verbose -Path $_ -Destination $dest -Force   

Allowed memory size of 33554432 bytes exhausted (tried to allocate 43148176 bytes) in php

It is unfortunately easy to program in PHP in a way that consumes memory faster than you realise. Copying strings, arrays and objects instead of using references will do it, though PHP 5 is supposed to do this more automatically than in PHP 4. But dealing with your data set in entirety over several steps is also wasteful compared to processing the smallest logical unit at a time. The classic example is working with large resultsets from a database: most programmers fetch the entire resultset into an array and then loop over it one or more times with foreach(). It is much more memory efficient to use a while() loop to fetch and process one row at a time. The same thing applies to processing a file.

Mapping composite keys using EF code first

Through Configuration, you can do this:

    int fk_one,
    int fk_two

    int pk_one,
    int pk_two,

then in the context config

public class MyContext : DbContext
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
            .HasRequired(e => e.Model2)
            .WithMany(e => e.Model1s)
            .HasForeignKey(e => new { e.fk_one, e.fk_two })

Function to clear the console in R and RStudio


is the code to send CTRL+L to the console, and therefore will clear the screen.

Far better than just sending a whole lot of returns.

String to HtmlDocument

Using Html Agility Pack as suggested by SLaks, this becomes very easy:

string html = webClient.DownloadString(url);
var doc = new HtmlDocument();

HtmlNode specificNode = doc.GetElementById("nodeId");
HtmlNodeCollection nodesMatchingXPath = doc.DocumentNode.SelectNodes("x/path/nodes");

How to search a list of tuples in Python

Supposing the list may be long and the numbers may repeat, consider using the SortedList type from the Python sortedcontainers module. The SortedList type will automatically maintain the tuples in order by number and allow for fast searching.

For example:

from sortedcontainers import SortedList
sl = SortedList([(1,"juca"),(22,"james"),(53,"xuxa"),(44,"delicia")])

# Get the index of 53:

index = sl.bisect((53,))

# With the index, get the tuple:

tup = sl[index]

This will work a lot faster than the list comprehension suggestion by doing a binary search. The dictionary suggestion will be faster still but won't work if there could be duplicate numbers with different strings.

If there are duplicate numbers with different strings then you need to take one more step:

end = sl.bisect((53 + 1,))

results = sl[index:end]

By bisecting for 54, we will find the end index for our slice. This will be significantly faster on long lists as compared with the accepted answer.

How do I recursively delete a directory and its entire contents (files + sub dirs) in PHP?

function rmdir_recursive( $dirname ) {

     * FilesystemIterator and SKIP_DOTS

    if ( class_exists( 'FilesystemIterator' ) && defined( 'FilesystemIterator::SKIP_DOTS' ) ) {

        if ( !is_dir( $dirname ) ) {
            return false;

        foreach( new RecursiveIteratorIterator( new RecursiveDirectoryIterator( $dirname, FilesystemIterator::SKIP_DOTS ), RecursiveIteratorIterator::CHILD_FIRST ) as $path ) {
            $path->isDir() ? rmdir( $path->getPathname() ) : unlink( $path->getRealPath() );

        return rmdir( $dirname );


     * RecursiveDirectoryIterator and SKIP_DOTS

    if ( class_exists( 'RecursiveDirectoryIterator' ) && defined( 'RecursiveDirectoryIterator::SKIP_DOTS' ) ) {

        if ( !is_dir( $dirname ) ) {
            return false;

        foreach( new RecursiveIteratorIterator( new RecursiveDirectoryIterator( $dirname, RecursiveDirectoryIterator::SKIP_DOTS ), RecursiveIteratorIterator::CHILD_FIRST ) as $path ) {
            $path->isDir() ? rmdir( $path->getPathname() ) : unlink( $path->getRealPath() );

        return rmdir( $dirname );


     * RecursiveIteratorIterator and RecursiveDirectoryIterator

    if ( class_exists( 'RecursiveIteratorIterator' ) && class_exists( 'RecursiveDirectoryIterator' ) ) {

        if ( !is_dir( $dirname ) ) {
            return false;

        foreach( new RecursiveIteratorIterator( new RecursiveDirectoryIterator( $dirname ), RecursiveIteratorIterator::CHILD_FIRST ) as $path ) {
            if ( in_array( $path->getFilename(), array( '.', '..' ) ) ) {
            $path->isDir() ? rmdir( $path->getPathname() ) : unlink( $path->getRealPath() );

        return rmdir( $dirname );


     * Scandir Recursive

    if ( !is_dir( $dirname ) ) {
        return false;

    $objects = scandir( $dirname );

    foreach ( $objects as $object ) {
        if ( $object === '.' || $object === '..' ) {
        filetype( $dirname . DIRECTORY_SEPARATOR . $object ) === 'dir' ? rmdir_recursive( $dirname . DIRECTORY_SEPARATOR . $object ) : unlink( $dirname . DIRECTORY_SEPARATOR . $object );

    reset( $objects );
    rmdir( $dirname );

    return !is_dir( $dirname );


Python - Module Not Found

All modules in Python have to have a certain directory structure. You can find details here.

Create an empty file called under the model directory, such that your directory structure would look something like that:

+-- project
    +-- src
        +-- model

Also in your file change the import statement to the following:

from model.order import SellOrder

That should fix it

P.S.: If you are placing your model directory in some other location (not in the same directory branch), you will have to modify the python path using sys.path.

Android LinearLayout : Add border with shadow around a LinearLayout

This is so simple:

Create a drawable file with a gradient like this:

for shadow below a view below_shadow.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="">   
    android:angle="270" >

for shadow above a view above_shadow.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="">   
    android:angle="90" >

and so on for right and left shadow just change the angle of the gradient :)

The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication

we are using MSMQ in our system, this error message came. The reason was our queue was full and we did not handle the error logging mechanism properly so we were getting the above exception instead of msmq ful. We cleared the messages then it is working fine.

How to install Google Play Services in a Genymotion VM (with no drag and drop support)?

Now Gapps provide way to install gapps package thorough apk.

Download APK and installation instruction from below link:

You can download current APK from below link:

Play store link:

Current version Website Link (7/22/2017):

enter image description here

Parsing Query String in node.js

node -v v9.10.1

If you try to console log query object directly you will get error TypeError: Cannot convert object to primitive value

So I would suggest use JSON.stringify

const http = require('http');
const url = require('url');

const server = http.createServer((req, res) => {
    const parsedUrl = url.parse(req.url, true);

    const path = parsedUrl.pathname, query = parsedUrl.query;
    const method = req.method;

    res.end("hello world\n");

    console.log(`Request received on: ${path} + method: ${method} + query: 
    console.log('query: ', query);

  server.listen(3000, () => console.log("Server running at port 3000"));

So doing curl http://localhost:3000/foo\?fizz\=buzz will return Request received on: /foo + method: GET + query: {"fizz":"buzz"}

Why does AngularJS include an empty option in select?

We can use CSS to hide the first option , But it wont work in IE 10, 11. The best way is to remove the element using Jquery. This solution works for major browser tested in chrome and IE10 ,11

Also if you are using angular , sometime using setTimeout works

$scope.RemoveFirstOptionElement = function (element) {
    setTimeout(function () {
    }, 0);

Get everything after and before certain character in SQL Server

You can try this:

Declare @test varchar(100)='images/test.jpg'
Select REPLACE(RIGHT(@test,charindex('/',reverse(@test))-1),'.jpg','')

How to convert 2D float numpy array to 2D int numpy array?

Some numpy functions for how to control the rounding: rint, floor,trunc, ceil. depending how u wish to round the floats, up, down, or to the nearest int.

>>> x = np.array([[1.0,2.3],[1.3,2.9]])
>>> x
array([[ 1. ,  2.3],
       [ 1.3,  2.9]])
>>> y = np.trunc(x)
>>> y
array([[ 1.,  2.],
       [ 1.,  2.]])
>>> z = np.ceil(x)
>>> z
array([[ 1.,  3.],
       [ 2.,  3.]])
>>> t = np.floor(x)
>>> t
array([[ 1.,  2.],
       [ 1.,  2.]])
>>> a = np.rint(x)
>>> a
array([[ 1.,  2.],
       [ 1.,  3.]])

To make one of this in to int, or one of the other types in numpy, astype (as answered by BrenBern):

array([[1, 2],
       [1, 3]])

>>> y.astype(int)
array([[1, 2],
       [1, 2]])

Git Push ERROR: Repository not found

If your repo was working normally before, and suddenly this error pops up, most likely the reason would be that your git is authenticated as some other user, that does not have access to the repository. So, in order to push, all you need to do is, specify your correct username and password in your git command. So, a push command for a github repo would look like:

git push https://youruser:[email protected]/user/reponame.git

username and password needs to be url-escaped, so an @ should be replaced by %40, and so on.

Get restaurants near my location

Is this what you are looking for?,-123.137784&radius=500&sensor=false&key=*PlacesAPIKey*&types=restaurant

types is optional

How can I ssh directly to a particular directory?

going one step further with the -t idea. I keep a set of scripts calling the one below to go to specific places in my frequently visited hosts. I keep them all in ~/bin and keep that directory in my path.


# does ssh session switching to particular directory
# $1, hostname from config file 
# $2, directory to move to after login
# can save this as say 'con' then
# make another script calling this one, e.g.
# con myhost repos/i2c

ssh -t $1 "cd $2; exec \$SHELL --login"

Convert a python 'type' object to a string

In case you want to use str() and a custom str method. This also works for repr.

class TypeProxy:
    def __init__(self, _type):
        self._type = _type

    def __call__(self, *args, **kwargs):
        return self._type(*args, **kwargs)

    def __str__(self):
        return self._type.__name__

    def __repr__(self):
        return "TypeProxy(%s)" % (repr(self._type),)

>>> str(TypeProxy(str))
>>> str(TypeProxy(type("")))

How to create JSON object Node.js

The other answers are helpful, but the JSON in your question isn't valid. I have formatted it to make it clearer below, note the missing single quote on line 24.

  1 {
  2     'Orientation Sensor':
  3     [
  4         {
  5             sampleTime: '1450632410296',
  6             data: '76.36731:3.4651554:0.5665419'
  7         },
  8         {
  9             sampleTime: '1450632410296',
 10             data: '78.15431:0.5247617:-0.20050584'
 11         }
 12     ],
 13     'Screen Orientation Sensor':
 14     [
 15         {
 16             sampleTime: '1450632410296',
 17             data: '255.0:-1.0:0.0'
 18         }
 19     ],
 20     'MPU6500 Gyroscope sensor UnCalibrated':
 21     [
 22         {
 23             sampleTime: '1450632410296',
 24             data: '-0.05006743:-0.013848438:-0.0063915867
 25         },
 26         {
 27             sampleTime: '1450632410296',
 28             data: '-0.051132694:-0.0127831735:-0.003325345'
 29         }
 30     ]
 31 }

There are a lot of great articles on how to manipulate objects in Javascript (whether using Node JS or a browser). I suggest here is a good place to start:

how to access iFrame parent page using jquery?

To find in the parent of the iFrame use:

$('#parentPrice', window.parent.document).html();

The second parameter for the $() wrapper is the context in which to search. This defaults to document.

Instagram how to get my user id from username?

Very late answer but I think this is the best answer of this topic. Hope this is useful.

You can get user info when a request is made with the url below:{username}/?__a=1


This url will get all information about a user whose username is therock

Update i June-20-2019, the API is public now. No authentication required.

Update in December-11-2018, I needed to confirm that this endpoint still work. You need to login before sending request to this site because it's not public endpoint anymore. The login step is easy also. This is my demo:

Update in Apr-17-2018, it's look like this endpoint still working (but its not public endpoint anymore), you must send a request with extra information to that endpoint. (Press F12 to open developer toolbar, then click to Network Tab and trace the request.)

Sorry because I'm too busy. Hope this information help you guys. Hmm, feel free to give me a down-vote if you want.

Update in Apr-12-2018, cameronjonesweb said that this endpoint doesn't work anymore. When he/she trying to access this endpoint, 403 status code return.

Add external libraries to CMakeList.txt c++

I would start with upgrade of CMAKE version.

You can use INCLUDE_DIRECTORIES for header location and LINK_DIRECTORIES + TARGET_LINK_LIBRARIES for libraries

rosbuild_add_executable(kinectueye src/kinect_ueye.cpp)
TARGET_LINK_LIBRARIES(kinectueye lib1 lib2 lib2 ...)

note that lib1 is expanded to (on Linux), so use ln to create appropriate links in case you do not have them

Twig ternary operator, Shorthand if-then-else

You can use shorthand syntax as of Twig 1.12.0

{{ foo ?: 'no' }} is the same as {{ foo ? foo : 'no' }}
{{ foo ? 'yes' }} is the same as {{ foo ? 'yes' : '' }}

Using context in a fragment

You have different options:

  • If your minSDK <= 21, then you can use getActivity(), since this is a Context.
  • If your minSDK is >=23, then you can use getContext().

If you don't need to support old versions then go with getContext().

Java 8 method references: provide a Supplier capable of supplying a parameterized result

It appears that you can throw only RuntimeException from the method orElseThrow. Otherwise you will get an error message like MyException cannot be converted to java.lang.RuntimeException

Update:- This was an issue with an older version of JDK. I don't see this issue with the latest versions.

How to split strings over multiple lines in Bash?

However, if you have indented code, it doesn't work out so well:

    echo "continuation \
>continuation     lines

Try with single quotes and concatenating the strings:

    echo 'continuation' \
>continuation lines

Note: the concatenation includes a whitespace.

css overflow - only 1 line of text

the best code for UX and UI is

white-space: nowrap;
text-overflow: ellipsis;
overflow: hidden;
display: inherit;

Detect Android phone via Javascript / jQuery

js version, catches iPad too:

var is_mobile = /mobile|android/i.test (navigator.userAgent);

How to run a task when variable is undefined in ansible?

From the ansible docs: If a required variable has not been set, you can skip or fail using Jinja2’s defined test. For example:


- shell: echo "I've got '{{ foo }}' and am not afraid to use it!"
  when: foo is defined

- fail: msg="Bailing out. this play requires 'bar'"
  when: bar is not defined

So in your case, when: deployed_revision is not defined should work

C#: Printing all properties of an object

The ObjectDumper class has been known to do that. I've never confirmed, but I've always suspected that the immediate window uses that.

EDIT: I just realized, that the code for ObjectDumper is actually on your machine. Go to:

C:/Program Files/Microsoft Visual Studio 9.0/Samples/1033/

This will unzip to a folder called LinqSamples. In there, there's a project called ObjectDumper. Use that.

.mp4 file not playing in chrome

This started out as an attempt to cast video from my pc to a tv (with subtitles) eventually using Chromecast. And I ended up in this "does not play mp4" situation. However I seemed to have proved that Chrome will play (exactly the same) mp4 as long as it isn't wrapped in html(5) So here is what I have constructed. I have made a webpage under localhost and in there is a default.htm which contains:-

<!DOCTYPE html>
<video  controls >
 <source src="sample.mp4" type="video/mp4">
 <track kind="subtitles" src="sample.vtt" label="gcsubs" srclang="eng">

the video and subtitle files are stored in the same folder as default.htm

I have the very latest version of Chrome (just updated this morning)

When I type the appropriate localhost... into my Chrome browser a black square appears with a "GO" arrow and an elapsed time bar, a mute button and an icon which says "CC". If I hit the go arrow, nothing happens (it doesn't change to "pause", the elapsed time doesn't move, and the timer sticks at 0:00. There are no error messages - nothing!

(note that if I input localhost.. to IE11 the video plays!!!!

In Chrome if I enter the disc address of sample.mp4 (i.e. C:\webstore\sample.mp4 then Chrome will play the video fine?.

This last bit is probably a working solution for Chromecast except that I cannot see any subtitles. I really want a solution with working subtitles. I just don't understand what is different in Chrome between the two methods of playing mp4

Visual Studio loading symbols

For me, it seems related to breakpoints, as indicated in the accepted answer. However, I found two workarounds that did not involve deleting all the breakpoints:

  • Restarting Visual Studio seemed to fix it temporarily.
  • Clicking the "X" button to close Visual Studio while debugging causes the "Do you want to stop debugging?" message box to pop up; while this message box is up, the symbols load at ordinary speeds. Once all the symbols are loaded, you can click "No" to cancel the close.

Pass a variable to a PHP script running from the command line

You could use what sep16 on recommends:


parse_str(implode('&', array_slice($argv, 1)), $_GET);


It behaves exactly like you'd expect with cgi-php.

$ php -f myfile.php type=daily a=1 b[]=2 b[]=3

will set $_GET['type'] to 'daily', $_GET['a'] to '1' and $_GET['b'] to array('2', '3').

How to check identical array in most efficient way?

So, what's wrong with checking each element iteratively?

function arraysEqual(arr1, arr2) {
    if(arr1.length !== arr2.length)
        return false;
    for(var i = arr1.length; i--;) {
        if(arr1[i] !== arr2[i])
            return false;

    return true;

How to move from one fragment to another fragment on click of an ImageView in Android?

When you are inside an activity and need to go to a fragment use below

getFragmentManager().beginTransaction().replace(*TO_BE_REPLACED_LAYOUT_ID*, new tasks()).commit();

But when you are inside a fragment and need to go to a fragment then just add a getActivity(). before, so it would become

getActivity().getFragmentManager().beginTransaction().replace(*TO_BE_REPLACED_LAYOUT_ID*, new tasks()).commit();

as simple as that.

The *TO_BE_REPLACED_LAYOUT_ID* can be the entire page of activity or a part of it, just make sure to put an id to the layout to be replaced. It is general practice to put the replaceable layout in a FrameLayout .

Create a git patch from the uncommitted changes in the current working directory

git diff and git apply will work for text files, but won't work for binary files.

You can easily create a full binary patch, but you will have to create a temporary commit. Once you've made your temporary commit(s), you can create the patch with:

git format-patch <options...>

After you've made the patch, run this command:

git reset --mixed <SHA of commit *before* your working-changes commit(s)>

This will roll back your temporary commit(s). The final result leaves your working copy (intentionally) dirty with the same changes you originally had.

On the receiving side, you can use the same trick to apply the changes to the working copy, without having the commit history. Simply apply the patch(es), and git reset --mixed <SHA of commit *before* the patches>.

Note that you might have to be well-synced for this whole option to work. I've seen some errors when applying patches when the person making them hadn't pulled down as many changes as I had. There are probably ways to get it to work, but I haven't looked far into it.

Here's how to create the same patches in Tortoise Git (not that I recommend using that tool):

  1. Commit your working changes
  2. Right click the branch root directory and click Tortoise Git -> Create Patch Serial
    1. Choose whichever range makes sense (Since: FETCH_HEAD will work if you're well-synced)
    2. Create the patch(es)
  3. Right click the branch root directory and click Tortise Git -> Show Log
  4. Right click the commit before your temporary commit(s), and click reset "<branch>" to this...
  5. Select the Mixed option

And how to apply them:

  1. Right click the branch root directory and click Tortoise Git -> Apply Patch Serial
  2. Select the correct patch(es) and apply them
  3. Right click the branch root directory and click Tortise Git -> Show Log
  4. Right click the commit before the patch's commit(s), and click reset "<branch>" to this...
  5. Select the Mixed option

Sometimes adding a WCF Service Reference generates an empty reference.cs

In my case I had a solution with VB Web Forms project that referenced a C# UserControl. Both the VB project and the CS project had a Service Reference to the same service. The reference appeared under Service References in the VB project and under the Connected Services grouping in the CS (framework) project.

In order to update the service reference (ie, get the Reference.vb file to not be empty) in the VB web forms project, I needed to REMOVE THE CS PROJECT, then update the VB Service Reference, then add the CS project back into the solution.

Override valueof() and toString() in Java enum

How about a Java 8 implementation? (null can be replaced by your default Enum)

public static RandomEnum getEnum(String value) {
    return -> m.value.equals(value)).findAny().orElse(null);

Or you could use:


When a 'blur' event occurs, how can I find out which element focus went *to*?

Edit: A hacky way to do it would be to create a variable that keeps track of focus for every element you care about. So, if you care that 'myInput' lost focus, set a variable to it on focus.

<script type="text/javascript">
   var lastFocusedElement;
<input id="myInput" onFocus="lastFocusedElement=this;" />

Original Answer: You can pass 'this' to the function.

<input id="myInput" onblur="function(this){
   var theId =; // will be 'myInput'
}" />

How to check if function exists in JavaScript?

I have also been looking for an elegant solution to this problem. After much reflection, I found this approach best.

const func = me.onChange || (str => {}); func(str);

Android widget: How to change the text of a button

I had a button in my layout.xml that was defined as a View as in:

final View myButton = findViewById(;

I was not able to change the text on it until I also defined it as a button:

final View vButton = findViewById(;
final Button bButton = (Button) findViewById(;

When I needed to change the text, I used the bButton.setText("Some Text"); and when I wanted to alter the view, I used the vButton.

Worked great!

How to escape special characters of a string with single backslashes

re.escape doesn't double escape. It just looks like it does if you run in the repl. The second layer of escaping is caused by outputting to the screen.

When using the repl, try using print to see what is really in the string.

$ python
>>> import re
>>> re.escape("\^stack\.\*/overflo\\w\$arr=1")
>>> print re.escape("\^stack\.\*/overflo\\w\$arr=1")

Trim a string in C

/* Function to remove white spaces on both sides of a string i.e trim */

void trim (char *s)
    int i;

    while (isspace (*s)) s++;   // skip left side white spaces
    for (i = strlen (s) - 1; (isspace (s[i])); i--) ;   // skip right side white spaces
    s[i + 1] = '\0';
    printf ("%s\n", s);

How to round the minute of a datetime object

if you don't want to use condition, you can use modulo operator:

minutes = int(round(tm.minute, -1)) % 60


did you want something like this?

def timeround10(dt):
    a, b = divmod(round(dt.minute, -1), 60)
    return '%i:%02i' % ((dt.hour + a) % 24, b)

timeround10(datetime.datetime(2010, 1, 1, 0, 56, 0)) # 0:56
# -> 1:00

timeround10(datetime.datetime(2010, 1, 1, 23, 56, 0)) # 23:56
# -> 0:00

.. if you want result as string. for obtaining datetime result, it's better to use timedelta - see other responses ;)

Git diff -w ignore whitespace only at start & end of lines

For end of line use:

git diff --ignore-space-at-eol

Instead of what are you using currently:

git diff -w (--ignore-all-space)

For start of line... you are out of luck if you want a built in solution.

However, if you don't mind getting your hands dirty there's a rather old patch floating out there somewhere that adds support for "--ignore-space-at-sol".

Turning off some legends in a ggplot

You can use guide=FALSE in scale_..._...() to suppress legend.

For your example you should use scale_colour_continuous() because length is continuous variable (not discrete).

(p3 <- ggplot(mov, aes(year, rating, colour = length, shape = mpaa)) +
   scale_colour_continuous(guide = FALSE) +

Or using function guides() you should set FALSE for that element/aesthetic that you don't want to appear as legend, for example, fill, shape, colour.

p0 <- ggplot(mov, aes(year, rating, colour = length, shape = mpaa)) +


Both provided solutions work in new ggplot2 version 2.0.0 but movies dataset is no longer present in this library. Instead you have to use new package ggplot2movies to check those solutions.

mov <- subset(movies, length != "")

Build not visible in itunes connect

Well, in my case I uploaded a build with updated version. like 1.1.0 Build 1.1.0, then I reverted back to 1.0.0 build 1.0.5 and the same build was visible under the 1.0.0 header dropdown.

Hope it helps someone.

How to make the webpack dev server run on port 80 and on to make it publicly accessible?

In package.json change the "start" value as follows

Note: Run $sudo npm start, You need to use sudo to run react scripts on port 80

enter image description here

count number of lines in terminal output

Pipe the result to wc using the -l (line count) switch:

grep -Rl "curl" ./ | wc -l

C++ Remove new line from multiline string

About answer 3 removing only the last \n off string code :

if (!s.empty() && s[s.length()-1] == '\n') {

Will the if condition not fail if the string is really empty ?

Is it not better to do :

if (!s.empty())
    if (s[s.length()-1] == '\n')

Visual Studio 2012 Web Publish doesn't copy files

I ran into the same problem on VS 2010, after checking publish output, event logs, turning on and checking visual studio logs etc I then decided to remove the web publish (via add/remove) which I believe had been recently updated to v1.0.30810.0. This resolved the problem.

ERROR 1049 (42000): Unknown database

blog_development doesn't exist

You can see this in sql by the 0 rows affected message

create it in mysql with

mysql> create database blog_development

However as you are using rails you should get used to using

$ rake db:create

to do the same task. It will use your database.yml file settings, which should include something like:

  adapter: mysql2
  database: blog_development
  pool: 5

Also become familiar with:

$ rake db:migrate  # Run the database migration
$ rake db:seed     # Run thew seeds file create statements
$ rake db:drop     # Drop the database

Displaying better error message than "No JSON object could be decoded"

When your file is created. Instead of creating a file with content is empty. Replace with:

json.dump({}, file)

Is there a short cut for going back to the beginning of a file by vi editor?

using :<line number> you can navigate to any line, thus :1 takes you to the first line.

SQL left join vs multiple tables on FROM line?

The second is preferred because it is far less likely to result in an accidental cross join by forgetting to put inthe where clause. A join with no on clause will fail the syntax check, an old style join with no where clause will not fail, it will do a cross join.

Additionally when you later have to a left join, it is helpful for maintenance that they all be in the same structure. And the old syntax has been out of date since 1992, it is well past time to stop using it.

Plus I have found that many people who exclusively use the first syntax don't really understand joins and understanding joins is critical to getting correct results when querying.

Android Left to Right slide animation

If you want the transition work for whole application you can create a rootacivity and inherit it in the activity you need. In Root Activity's onCreate call overridePendingTransition with desired direction. And onStart call overridePendingTransition with other direction if activity is resumed. Here I am giving full running code below.Correct me if I am wrong.

create this xml file on your anim folder


<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="" >
        android:toXDelta="0%" >


<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="" >
        android:toXDelta="0%" >


<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="" >
        android:toXDelta="-100%" >


<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="" >
        android:toXDelta="100%" >


import android.os.Bundle;

public class RootActivity extends Activity {
    int onStartCount = 0;

    protected void onCreate(Bundle savedInstanceState) {
        onStartCount = 1;
        if (savedInstanceState == null) // 1st time
        } else // already created so reverse animation
            onStartCount = 2;

    protected void onStart() {
        // TODO Auto-generated method stub
        if (onStartCount > 1) {

        } else if (onStartCount == 1) {




import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class FirstActivity extends RootActivity {
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        TextView tv = (TextView) findViewById(;
        tv.setText("First Activity");
        Button bt = (Button) findViewById(;
        bt.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                Intent i = new Intent(FirstActivity.this, SecondActivity.class);




import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class SecondActivity extends RootActivity {
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        TextView tv = (TextView) findViewById(;
        tv.setText("Second Activity");
        Button bt = (Button) findViewById(;
        bt.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                Intent i = new Intent(SecondActivity.this, ThirdActivity.class);





import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class ThirdActivity extends RootActivity {
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        TextView tv = (TextView) findViewById(;
        tv.setText("Third Activity");
        Button bt = (Button) findViewById(;
        bt.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {



and finally Manifest

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

        android:targetSdkVersion="18" />

        android:theme="@style/AppTheme" >
            android:label="@string/app_name" >
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            android:label="@string/app_name" >
            android:label="@string/app_name" >


Why doesn't C++ have a garbage collector?

Imposing garbage collection is really a low level to high level paradigm shift.

If you look at the way strings are handled in a language with garbage collection, you will find they ONLY allow high level string manipulation functions and do not allow binary access to the strings. Simply put, all string functions first check the pointers to see where the string is, even if you are only drawing out a byte. So if you are doing a loop that processes each byte in a string in a language with garbage collection, it must compute the base location plus offset for each iteration, because it cannot know when the string has moved. Then you have to think about heaps, stacks, threads, etc etc.

Difference between document.addEventListener and window.addEventListener?

The window binding refers to a built-in object provided by the browser. It represents the browser window that contains the document. Calling its addEventListener method registers the second argument (callback function) to be called whenever the event described by its first argument occurs.

<p>Some paragraph.</p>
  window.addEventListener("click", () => {

Following points should be noted before select window or document to addEventListners

  1. Most of the events are same for window or document but some events like resize, and other events related to loading, unloading, and opening/closing should all be set on the window.
  2. Since window has the document it is good practice to use document to handle (if it can handle) since event will hit document first.
  3. Internet Explorer doesn't respond to many events registered on the window,so you will need to use document for registering event.

How to add an empty column to a dataframe?

Starting with v0.16.0, DF.assign() could be used to assign new columns (single/multiple) to a DF. These columns get inserted in alphabetical order at the end of the DF.

This becomes advantageous compared to simple assignment in cases wherein you want to perform a series of chained operations directly on the returned dataframe.

Consider the same DF sample demonstrated by @DSM:

df = pd.DataFrame({"A": [1,2,3], "B": [2,3,4]})
   A  B
0  1  2
1  2  3
2  3  4

   A  B C   D
0  1  2   NaN
1  2  3   NaN
2  3  4   NaN

Note that this returns a copy with all the previous columns along with the newly created ones. In order for the original DF to be modified accordingly, use it like : df = df.assign(...) as it does not support inplace operation currently.

Formatting floats without trailing zeros

You could use %g to achieve this:


or, with Python = 2.6:


From the docs for format: g causes (among other things)

insignificant trailing zeros [to be] removed from the significand, and the decimal point is also removed if there are no remaining digits following it.

GDB: break if variable equal value

You can use a watchpoint for this (A breakpoint on data instead of code).

You can start by using watch i.
Then set a condition for it using condition <breakpoint num> i == 5

You can get the breakpoint number by using info watch

Lost connection to MySQL server at 'reading initial communication packet', system error: 0

Had this problem when setting up a new slave server. Found it was the slave server IP address was missing from the master server /etc/hosts.allow file. Added the IP address and it let me connect to the master server.

Note that I use hosts.allow and hosts.deny to control access.

Run a php app using tomcat?

Caucho Quercus can run PHP code on the jvm.

How to change Toolbar home icon color

This answer maybe too late, but here is how I do it. Styling the toolbar will do the trick. Create toolbar.xml with following code.

<?xml version="1.0" encoding="utf-8"?>
local:popupTheme="@style/ThemeOverlay.AppCompat.Light" />

and in the styles.xml

<style name="AppBaseTheme" parent="Theme.AppCompat.Light.NoActionBar">

<!-- Application theme. -->
<style name="AppTheme" parent="AppBaseTheme">
    <item name="windowNoTitle">true</item>
    <item name="windowActionBar">false</item>
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>

Finally, include the toolbar inside layout

        layout="@layout/toolbar" />

Copying and pasting data using VBA code

'So from this discussion i am thinking this should be the code then.

Sub Button1_Click()
    Dim excel As excel.Application
    Dim wb As excel.Workbook
    Dim sht As excel.Worksheet
    Dim f As Object

    Set f = Application.FileDialog(3)
    f.AllowMultiSelect = False

    Set excel = CreateObject("excel.Application")
    Set wb = excel.Workbooks.Open(f.SelectedItems(1))
    Set sht = wb.Worksheets("Data")

    Range("A1").PasteSpecial Paste:=xlPasteValues

End Sub

'Let me know if this is correct or a step was missed. Thx.

Why does jQuery or a DOM method such as getElementById not find the element?

This solution is for the people who don't use jQuery and to improve performance by not moving the script to bottom of the page, and the problem is that the script is loaded before the html elements are loaded. Add your code in this function body

    // your code here

    // example
    let element=document.getElementById("elementId");


add everything that has to work only after the document is loaded and keep other functions that has to be executed as soon as the script is loaded outside the function.

I recommend this method instead of moving down the script, because if the script is on top, the browser will try to download it as soon as it sees the script tag, if it is on the bottom of the page, it will take some more time to load it and until that time no event listeners in the script will work. in this case all other functions could be called and the window.onload will get called once everything is loaded.

MSSQL Regular expression

Thank you all for your help.

This is what I have used in the end:

  CASE WHEN [url] NOT LIKE '%[^-A-Za-z0-9/.+$]%' 
    THEN 'Valid' 
    ELSE 'No valid' 
  END [Validate]
  ORDER BY [Validate]

How to get the current URL within a Django template?

You can get the url without parameters by using {{request.path}} You can get the url with parameters by using {{request.get_full_path}}

How can I set the PATH variable for javac so I can manually compile my .java works?

Follow the steps given here

after setting variable, just navigate to your java file directory in your cmd and type javac ""

or if you don't navigate to the directory, then simply specify the full path of java file

javac "/"

Return single column from a multi-dimensional array

Although this question is related to string conversion, I stumbled upon this while wanting an easy way to write arrays to my log files. If you just want the info, and don't care about the exact cleanliness of a string you might consider:


jquery how to use multiple ajax calls one after the end of the other

Wrap each ajax call in a named function and just add them to the success callbacks of the previous call:

function callA() {
    success: function() {
      //do stuff

function callB() {
    success: function() {
        //do stuff

function callC() {


How can I be notified when an element is added to the page?

Between the deprecation of mutation events and the emergence of MutationObserver, an efficent way to be notified when a specific element was added to the DOM was to exploit CSS3 animation events.

To quote the blog post:

Setup a CSS keyframe sequence that targets (via your choice of CSS selector) whatever DOM elements you want to receive a DOM node insertion event for. I used a relatively benign and little used css property, clip I used outline-color in an attempt to avoid messing with intended page styles – the code once targeted the clip property, but it is no longer animatable in IE as of version 11. That said, any property that can be animated will work, choose whichever one you like.

Next I added a document-wide animationstart listener that I use as a delegate to process the node insertions. The animation event has a property called animationName on it that tells you which keyframe sequence kicked off the animation. Just make sure the animationName property is the same as the keyframe sequence name you added for node insertions and you’re good to go.

How to remove all white spaces in java

String a="string with                multi spaces ";

String b= a.replace("    "," ").replace("   "," ").replace("  "," ").replace("   "," ").replace("  "," ");

//it work fine with any spaces

Trying to create a file in Android: open failed: EROFS (Read-only file system)

I have tried this with and without the WRITE_INTERNAL_STORAGE permission.

There is no WRITE_INTERNAL_STORAGE permission in Android.

How do I create this file for writing?

You don't, except perhaps on a rooted device, if your app is running with superuser privileges. You are trying to write to the root of internal storage, which apps do not have access to.

Please use the version of the FileOutputStream constructor that takes a File object. Create that File object based off of some location that you can write to, such as:

  • getFilesDir() (called on your Activity or other Context)
  • getExternalFilesDir() (called on your Activity or other Context)

The latter will require WRITE_EXTERNAL_STORAGE as a permission.

Is there an easier way than writing it to a file then reading from it again?

You can temporarily put it in a static data member.

because many people don't have SD card slots

"SD card slots" are irrelevant, by and large. 99% of Android device users will have external storage -- the exception will be 4+ year old devices where the user removed their SD card. Devices manufactured since mid-2010 have external storage as part of on-board flash, not as removable media.

How to store image in SQL Server database tables column

Insert Into FEMALE(ID, Image)
Select '1', BulkColumn 
from Openrowset (Bulk 'D:\thepathofimage.jpg', Single_Blob) as Image

You will also need admin rights to run the query.

How to create a Restful web service with input parameters?

You can. Try something like this:

@Produces({"application/xml", "application/json"})
public Todo whatEverNameYouLike(@PathParam("varX") String varX,
    @PathParam("varY") String varY) {
        Todo todo = new Todo();
        return todo;

Then call your service with this URL;

Convert array to JSON string in swift

Hint: To convert an NSArray containing JSON compatible objects to an NSData object containing a JSON document, use the appropriate method of NSJSONSerialization. JSONObjectWithData is not it.

Hint 2: You rarely want that data as a string; only for debugging purposes.

long long int vs. long int vs. int64_t in C++

Do you want to know if a type is the same type as int64_t or do you want to know if something is 64 bits? Based on your proposed solution, I think you're asking about the latter. In that case, I would do something like

template<typename T>
bool is_64bits() { return sizeof(T) * CHAR_BIT == 64; } // or >= 64

Add new column in Pandas DataFrame Python

You just do an opposite comparison. if Col2 <= 1. This will return a boolean Series with False values for those greater than 1 and True values for the other. If you convert it to an int64 dtype, True becomes 1 and False become 0,

df['Col3'] = (df['Col2'] <= 1).astype(int)

If you want a more general solution, where you can assign any number to Col3 depending on the value of Col2 you should do something like:

df['Col3'] = df['Col2'].map(lambda x: 42 if x > 1 else 55)


df['Col3'] = 0
condition = df['Col2'] > 1
df.loc[condition, 'Col3'] = 42
df.loc[~condition, 'Col3'] = 55

Vertically center text in a 100% height div?

Setting the line height to the same as the height of the div will cause the text to center. Only works if there is one line. (such as a button).

How do I set up DNS for an apex domain (no www) pointing to a Heroku app?

To point your apex/root/naked domain at a Heroku-hosted application, you'll need to use a DNS provider who supports CNAME-like records (often referred to as ALIAS or ANAME records). Currently Heroku recommends:

Whichever of those you choose, your record will look like the following:

Record: ALIAS or ANAME

Name: empty or @


That's all you need.

However, it's not good for SEO to have both the www version and non-www version resolve. One should point to the other as the canonical URL. How you decide to do that depends on if you're using HTTPS or not. And if you're not, you probably should be as Heroku now handles SSL certificates for you automatically and for free for all applications running on paid dynos.

If you're not using HTTPS, you can just set up a 301 Redirect record with most DNS providers pointing name www to

If you are using HTTPS, you'll most likely need to handle the redirection at the application level. If you want to know why, check out these short and long explanations but basically since your DNS provider or other URL forwarding service doesn't have, and shouldn't have, your SSL certificate and private key, they can't respond to HTTPS requests for your domain.

To handle the redirects at the application level, you'll need to:

  • Add both your apex and www host names to the Heroku application (heroku domains:add and heroku domains:add
  • Set up your SSL certificates
  • Point your apex domain record at Heroku using an ALIAS or ANAME record as described above
  • Add a CNAME record with name www pointing to
  • And then in your application, 301 redirect any www requests to the non-www URL (here's an example of how to do it in Django)
  • Also in your application, you should probably redirect any HTTP requests to HTTPS (for example, in Django set SECURE_SSL_REDIRECT to True)

Check out this post from DNSimple for more.

How to create a DB for MongoDB container on start up?

If you are looking to remove usernames and passwords from your docker-compose.yml you can use Docker Secrets, here is how I have approached it.

version: '3.6'

    image: mongo:3
    container_name: mycontainer
    file:  secrets/${NODE_ENV}_mongo_root_username.txt
    file:  secrets/${NODE_ENV}_mongo_root_password.txt

I have use the file: option for my secrets however, you can also use external: and use the secrets in a swarm.

The secrets are available to any script in the container at /var/run/secrets

The Docker documentation has this to say about storing sensitive data...

You can use secrets to manage any sensitive data which a container needs at runtime but you don’t want to store in the image or in source control, such as:

Usernames and passwords TLS certificates and keys SSH keys Other important data such as the name of a database or internal server Generic strings or binary content (up to 500 kb in size)

How do I format a Microsoft JSON date?

You can use this to get a date from JSON:

var date = eval(jsonDate.replace(/\/Date\((\d+)\)\//gi, "new Date($1)"));

And then you can use a JavaScript Date Format script (1.2 KB when minified and gzipped) to display it as you want.

Gunicorn worker timeout error

If you are using GCP then you have to set workers per instance type.

Link to GCP best practices

Angular cli generate a service and include the provider in one step

In Angular 5.12 and latest Angular CLI, do

ng generate service my-service -m app.module

Submit form without page reloading

The page will get reloaded if you don't want to use javascript

Hibernate JPA Sequence (non-Id)

I know this is a very old question, but it's showed firstly upon the results and jpa has changed a lot since the question.

The right way to do it now is with the @Generated annotation. You can define the sequence, set the default in the column to that sequence and then map the column as:

@Column(name = "column_name", insertable = false)

Display QImage with QtGui

Simple, but complete example showing how to display QImage might look like this:

#include <QtGui/QApplication>
#include <QLabel>

int main(int argc, char *argv[])
    QApplication a(argc, argv);

    QImage myImage;

    QLabel myLabel;

    return a.exec();

What is the right way to POST multipart/form-data using curl?

I had a hard time sending a multipart HTTP PUT request with curl to a Java backend. I simply tried

curl -X PUT URL \
   --header 'Content-Type: multipart/form-data; boundary=---------BOUNDARY' \
   --data-binary @file

and the content of the file was

Content-Disposition: form-data; name="name1"
Content-Type: application/xml;version=1.0;charset=UTF-8

Content-Disposition: form-data; name="name2"
Content-Type: text/plain


but I always got an error that the boundary was incorrect. After some Java backend debugging I found out that the Java implementation was adding a \r\n-- as a prefix to the boundary, so after changing my input file to

                          <-- here's the CRLF
-------------BOUNDARY       <-- added '--' at the beginning
-------------BOUNDARY       <-- added '--' at the beginning
-------------BOUNDARY--     <-- added '--' at the beginning

everything works fine!


Add a newline (CRLF \r\n) at the beginning of the multipart boundary content and -- at the beginning of the boundaries and try again.

Maybe you are sending a request to a Java backend that needs this changes in the boundary.

Detecting when the 'back' button is pressed on a navbar

This works for me in iOS 9.3.x with Swift:

override func didMoveToParentViewController(parent: UIViewController?) {

    if parent == self.navigationController?.parentViewController {
        print("Back tapped")

Unlike other solutions here, this doesn't seem to trigger unexpectedly.

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

Bogobogosort. Yes, it's a thing. to Bogobogosort, you Bogosort the first element. Check to see if that one element is sorted. Being one element, it will be. Then you add the second element, and Bogosort those two until it's sorted. Then you add one more element, then Bogosort. Continue adding elements and Bogosorting until you have finally done every element. This was designed never to succeed with any sizable list before the heat death of the universe.

Converting List<Integer> to List<String>

Instead of using String.valueOf I'd use .toString(); it avoids some of the auto boxing described by @johnathan.holland

The javadoc says that valueOf returns the same thing as Integer.toString().

List<Integer> oldList = ...
List<String> newList = new ArrayList<String>(oldList.size());

for (Integer myInt : oldList) { 

NoClassDefFoundError while trying to run my jar with java.exe -jar...what's wrong?

i had the same problem with my jar the solution

  1. Create the MANIFEST.MF file:

Manifest-Version: 1.0

Sealed: true

Class-Path: . lib/jarX1.jar lib/jarX2.jar lib/jarX3.jar

Main-Class: com.MainClass

  1. Right click on project, Select Export.

select export all outpout folders for checked project

  1. select using existing manifest from workspace and select the MANIFEST.MF file

This worked for me :)

How to make a DIV not wrap?

Use display:flex and white-space:nowrap

<h2>Sample Text.</h2>_x000D_
<p>Some example text that will not wrap..lla et dictum interdum, nisi lorem egestas odio, vitae scelerisque enim ligula venenatis dolor. Maecenas nisl est, ultrices nec congue eget, auctor vitae massa. Fusce luctus vestibulum augue ut aliquet. Mauris ante ligula, facilisis sed ornare eu, lobortis in odio. Praesent convallis urna a lacus interdum ut hendrerit risus congue. Nunc sagittis dictum nisi, sed ullamcorper ipsum d</p>_x000D_
<h3>Then some other text</h3>

How can I check Drupal log files?

We came across many situation where we need to check error and error logs to figure out issue we are facing we can check by possibly following method:

1.) On blank screen Some time we got nothing but blank screen instead of our site or message written The website encountered an unexpected error. Please try again later , so we can Print Errors to the Screen by adding


ini_set('display_errors', TRUE); 

ini_set('display_startup_errors', TRUE); 

in index.php at top.;

2.) We should enable optional core module for Database Logging at /admin/build/modules, and then we can check logs your_domain_name/admin/reports/dblog

3.) We can use drush command also to check logs drush watchdog-show it will show recent ten message

or if we want to continue showing logs with more information we can user
drush watchdog-show --tail --full.

4.) Also we can enable core Syslog module this module logs events of operating system of any web server.

How to check whether a select box is empty using JQuery/Javascript

Another correct way to get selected value would be using this selector:


Best for you!

How can I force a hard reload in Chrome for Android

If its just the matter of included files, just add version after the path (?v=12345678)

<link rel="stylesheet" type="text/css" href="style.css?v=12345678" />

Whoever loads the page again will see changes.

How to Disable GUI Button in Java

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.BoxLayout;
import javax.swing.JSeparator;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

public class IPGUI extends JFrame implements ActionListener 
    private static JPanel contentPane;

    private JButton btnConvertDocuments;
    private JButton btnExtractImages;
    private JButton btnParseRIDValues;
    private JButton btnParseImageInfo;

    //Create the frame
    public IPGUI() 
        //Sets frame properties
        setTitle("IP Extractor");
        setBounds(100, 100, 250, 300);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        contentPane.setLayout(new BorderLayout(0, 0));

        //Creates new JPanel with boxlayout
        JPanel panel = new JPanel();
        contentPane.add(panel, BorderLayout.CENTER);
        panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));

        //////////////////New Button//////////////////

        JButton btnConvertDocuments = new JButton("1. Convert Documents");
        btnConvertDocuments.setMaximumSize(new Dimension(160, 0));
        btnConvertDocuments.setPreferredSize(new Dimension(0, 50));


        btnConvertDocuments.addActionListener((ActionListener) this);

        JSeparator separator_3 = new JSeparator();

        //////////////////New Button//////////////////

        btnExtractImages = new JButton("2. Extract Images");
        btnExtractImages.setMaximumSize(new Dimension(160, 0));
        btnExtractImages.setPreferredSize(new Dimension(0, 50));


        btnExtractImages.addActionListener((ActionListener) this);

        JSeparator separator_2 = new JSeparator();

        //////////////////New Button//////////////////

        JButton btnParseRIDValues = new JButton("3. Parse rId Values");
        btnParseRIDValues.setMaximumSize(new Dimension(160, 0));
        btnParseRIDValues.setPreferredSize(new Dimension(0, 50));


        btnParseRIDValues.addActionListener((ActionListener) this);

        JSeparator separator_1 = new JSeparator();

        //////////////////New Button//////////////////

        JButton btnParseImageInfo = new JButton("4. Parse Image Info.");
        btnParseImageInfo.setMaximumSize(new Dimension(160, 0));
        btnParseImageInfo.setPreferredSize(new Dimension(0, 50));


        btnParseImageInfo.addActionListener((ActionListener) this);

    public void actionPerformed(ActionEvent event) 
        String command = event.getActionCommand();

        if (command.equals("w"))
            FileConverter fc = new FileConverter();
        else if (command.equals("x"))
            ImageExtractor ie = new ImageExtractor();
        else if (command.equals("y")) 
            XMLIDParser xip = new XMLIDParser();
        else if (command.equals("z")) 
            XMLTagParser xtp = new XMLTagParser();


Here is the solution I came up with thanks to everyone's help. Thank you again everyone for your input, really appreciate it!

Use of Custom Data Types in VBA

It looks like you want to define Truck as a Class with properties NumberOfAxles, AxleWeights & AxleSpacings.

This can be defined in a CLASS MODULE (here named clsTrucks)

Option Explicit

Private tID As String
Private tNumberOfAxles As Double
Private tAxleSpacings As Double

Public Property Get truckID() As String
    truckID = tID
End Property

Public Property Let truckID(value As String)
    tID = value
End Property

Public Property Get truckNumberOfAxles() As Double
    truckNumberOfAxles = tNumberOfAxles
End Property

Public Property Let truckNumberOfAxles(value As Double)
    tNumberOfAxles = value
End Property

Public Property Get truckAxleSpacings() As Double
    truckAxleSpacings = tAxleSpacings
End Property

Public Property Let truckAxleSpacings(value As Double)
    tAxleSpacings = value
End Property

then in a MODULE the following defines a new truck and it's properties and adds it to a collection of trucks and then retrieves the collection.

Option Explicit

Public TruckCollection As New Collection

Sub DefineNewTruck()
Dim tempTruck As clsTrucks
Dim i As Long

    'Add 5 trucks
    For i = 1 To 5
        Set tempTruck = New clsTrucks
        'Random data
        tempTruck.truckID = "Truck" & i
        tempTruck.truckAxleSpacings = 13.5 + i
        tempTruck.truckNumberOfAxles = 20.5 + i

        'tempTruck.truckID is the collection key
        TruckCollection.Add tempTruck, tempTruck.truckID
    Next i

    'retrieve 5 trucks
    For i = 1 To 5
        'retrieve by collection index
        Debug.Print TruckCollection(i).truckAxleSpacings
        'retrieve by key
        Debug.Print TruckCollection("Truck" & i).truckAxleSpacings

    Next i

End Sub

There are several ways of doing this so it really depends on how you intend to use the data as to whether an a class/collection is the best setup or arrays/dictionaries etc.

Writing Unicode text to a text file?

Deal exclusively with unicode objects as much as possible by decoding things to unicode objects when you first get them and encoding them as necessary on the way out.

If your string is actually a unicode object, you'll need to convert it to a unicode-encoded string object before writing it to a file:

foo = u'?, ?, ?, ? ?, ?, ?, ?, ?, and ?.'
f = open('test', 'w')

When you read that file again, you'll get a unicode-encoded string that you can decode to a unicode object:

f = file('test', 'r')

How to restart service using command prompt?

PowerShell features a Restart-Service cmdlet, which either starts or restarts the service as appropriate.

The Restart-Service cmdlet sends a stop message and then a start message to the Windows Service Controller for a specified service. If a service was already stopped, it is started without notifying you of an error.

You can specify the services by their service names or display names, or you can use the InputObject parameter to pass an object that represents each service that you want to restart.

It is a little more foolproof than running two separate commands.

The easiest way to use it just pass either the service name or the display name directly:

Restart-Service 'Service Name'

It can be used directly from the standard cmd prompt with a command like:

powershell -command "Restart-Service 'Service Name'"