Programs & Examples On #Wonderware

Wonderware is a brand of industrial software sold by Schneider Electric.

.autocomplete is not a function Error

when you see this problem always put your autocomplete function in keyup function and ensure you have added the libraries

$( "#searcharea" ).keyup(function(){
   $( "#searcharea" ).autocomplete({
      source: "suggestions.php"
   });
});

Get data from file input in JQuery

FileReader API with jQuery, simple example.

_x000D_
_x000D_
( function ( $ ) {_x000D_
 // Add click event handler to button_x000D_
 $( '#load-file' ).click( function () {_x000D_
  if ( ! window.FileReader ) {_x000D_
   return alert( 'FileReader API is not supported by your browser.' );_x000D_
  }_x000D_
  var $i = $( '#file' ), // Put file input ID here_x000D_
   input = $i[0]; // Getting the element from jQuery_x000D_
  if ( input.files && input.files[0] ) {_x000D_
   file = input.files[0]; // The file_x000D_
   fr = new FileReader(); // FileReader instance_x000D_
   fr.onload = function () {_x000D_
    // Do stuff on onload, use fr.result for contents of file_x000D_
    $( '#file-content' ).append( $( '<div/>' ).html( fr.result ) )_x000D_
   };_x000D_
   //fr.readAsText( file );_x000D_
   fr.readAsDataURL( file );_x000D_
  } else {_x000D_
   // Handle errors here_x000D_
   alert( "File not selected or browser incompatible." )_x000D_
  }_x000D_
 } );_x000D_
} )( jQuery );
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<input type="file" id="file" />_x000D_
<input type='button' id='load-file' value='Load'>_x000D_
<div id="file-content"></div>
_x000D_
_x000D_
_x000D_

To read as text... uncomment //fr.readAsText(file); line and comment fr.readAsDataURL(file);

Objective-C declared @property attributes (nonatomic, copy, strong, weak)

Great answers! One thing that I would like to clarify deeper is nonatomic/atomic. The user should understand that this property - "atomicity" spreads only on the attribute's reference and not on it's contents. I.e. atomic will guarantee the user atomicity for reading/setting the pointer and only the pointer to the attribute. For example:

@interface MyClass: NSObject
@property (atomic, strong) NSDictionary *dict;
...

In this case it is guaranteed that the pointer to the dict will be read/set in the atomic manner by different threads. BUT the dict itself (the dictionary dict pointing to) is still thread unsafe, i.e. all read/add operations to the dictionary are still thread unsafe.

If you need thread safe collection you either have bad architecture (more often) OR real requirement (more rare). If it is "real requirement" - you should either find good&tested thread safe collection component OR be prepared for trials and tribulations writing your own one. It latter case look at "lock-free", "wait-free" paradigms. Looks like rocket-science at a first glance, but could help you achieving fantastic performance in comparison to "usual locking".

Convert row to column header for Pandas DataFrame,

This works (pandas v'0.19.2'):

df.rename(columns=df.iloc[0])

When to use CouchDB over MongoDB and vice versa

The answers above all over complicate the story.

  1. If you plan to have a mobile component, or need desktop users to work offline and then sync their work to a server you need CouchDB.
  2. If your code will run only on the server then go with MongoDB

That's it. Unless you need CouchDB's (awesome) ability to replicate to mobile and desktop devices, MongoDB has the performance, community and tooling advantage at present.

How to catch exception output from Python subprocess.check_output()?

Based on the answer of @macetw I print the exception directly to stderr in a decorator.

Python 3

from functools import wraps
from sys import stderr
from traceback import format_exc
from typing import Callable, Collection, Any, Mapping


def force_error_output(func: Callable):
    @wraps(func)
    def forced_error_output(*args: Collection[Any], **kwargs: Mapping[str, Any]):
        nonlocal func

        try:
            func(*args, **kwargs)
        except Exception as exception:
            stderr.write(format_exc())
            stderr.write("\n")
            stderr.flush()

            raise exception

    return forced_error_output

Python 2

from functools import wraps
from sys import stderr
from traceback import format_exc


def force_error_output(func):
    @wraps(func)
    def forced_error_output(*args, **kwargs):
        try:
            func(*args, **kwargs)
        except Exception as exception:
            stderr.write(format_exc())
            stderr.write("\n")
            stderr.flush()

            raise exception

    return forced_error_output

Then in your worker just use the decorator

@force_error_output
def da_worker(arg1: int, arg2: str):
    pass

How to update-alternatives to Python 3 without breaking apt?

replace

[bash:~] $ sudo update-alternatives --install /usr/bin/python python \
/usr/bin/python2.7 2

[bash:~] $ sudo update-alternatives --install /usr/bin/python python \
/usr/bin/python3.5 3

with

[bash:~] $ sudo update-alternatives --install /usr/local/bin/python python \
/usr/bin/python2.7 2

[bash:~] $ sudo update-alternatives --install /usr/local/bin/python python \
/usr/bin/python3.5 3

e.g. installing into /usr/local/bin instead of /usr/bin.

and ensure the /usr/local/bin is before /usr/bin in PATH.

i.e.

[bash:~] $ echo $PATH
/usr/local/bin:/usr/bin:/bin

Ensure this always is the case by adding

export PATH=/usr/local/bin:$PATH

to the end of your ~/.bashrc file. Prefixing the PATH environment variable with custom bin folder such as /usr/local/bin or /opt/<some install>/bin is generally recommended to ensure that customizations are found before the default system ones.

Check div is hidden using jquery

You can check the CSS display property:

if ($('#car').css('display') == 'none') {
    alert('Car 2 is hidden');
}

Here is a demo: http://jsfiddle.net/YjP4K/

window.close and self.close do not close the window in Chrome

Ordinary javascript cannot close windows willy-nilly. This is a security feature, introduced a while ago, to stop various malicious exploits and annoyances.

From the latest working spec for window.close():

The close() method on Window objects should, if all the following conditions are met, close the browsing context A:

  • The corresponding browsing context A is script-closable.
  • The browsing context of the incumbent script is familiar with the browsing context A.
  • The browsing context of the incumbent script is allowed to navigate the browsing context A.

A browsing context is script-closable if it is an auxiliary browsing context that was created by a script (as opposed to by an action of the user), or if it is a browsing context whose session history contains only one Document.

This means, with one small exception, javascript must not be allowed to close a window that was not opened by that same javascript.

Chrome allows that exception -- which it doesn't apply to userscripts -- however Firefox does not. The Firefox implementation flat out states:

This method is only allowed to be called for windows that were opened by a script using the window.open method.


If you try to use window.close from a Greasemonkey / Tampermonkey / userscript you will get:
Firefox: The error message, "Scripts may not close windows that were not opened by script."
Chrome: just silently fails.



The long-term solution:

The best way to deal with this is to make a Chrome extension and/or Firefox add-on instead. These can reliably close the current window.

However, since the security risks, posed by window.close, are much less for a Greasemonkey/Tampermonkey script; Greasemonkey and Tampermonkey could reasonably provide this functionality in their API (essentially packaging the extension work for you).
Consider making a feature request.



The hacky workarounds:

Chrome is currently was vulnerable to the "self redirection" exploit. So code like this used to work in general:

open(location, '_self').close();

This is buggy behavior, IMO, and is now (as of roughly April 2015) mostly blocked. It will still work from injected code only if the tab is freshly opened and has no pages in the browsing history. So it's only useful in a very small set of circumstances.

However, a variation still works on Chrome (v43 & v44) plus Tampermonkey (v3.11 or later). Use an explicit @grant and plain window.close(). EG:

// ==UserScript==
// @name        window.close demo
// @include     http://YOUR_SERVER.COM/YOUR_PATH/*
// @grant       GM_addStyle
// ==/UserScript==

setTimeout (window.close, 5000);

Thanks to zanetu for the update. Note that this will not work if there is only one tab open. It only closes additional tabs.


Firefox is secure against that exploit. So, the only javascript way is to cripple the security settings, one browser at a time.

You can open up about:config and set
allow_scripts_to_close_windows to true.

If your script is for personal use, go ahead and do that. If you ask anyone else to turn that setting on, they would be smart, and justified, to decline with prejudice.

There currently is no equivalent setting for Chrome.

How to tell which disk Windows Used to Boot

That depends on your definition of which disk drive Windows used to boot. I can think of 3 different answers on a standard BIOS system (who knows what an EFI system does):

  1. The drive that contains the active MBR
  2. The active partition, with NTLDR (the system partition)
  3. The partition with Windows on it (the boot partition)

2 and 3 should be easy to find - I'm not so sure about 1. Though you can raw disk read to find an MBR, that doesn't mean it's the BIOS boot device this time or even next time (you could have multiple disks with MBRs).

You really can't even be sure that the PC was started from a hard drive - it's perfectly possible to boot Windows from a floppy. In that case, both 1 and 2 would technically be a floppy disk, though 3 would remain C:\Windows.

You might need to be a bit more specific in your requirements or goals.

Sprintf equivalent in Java

Strings are immutable types. You cannot modify them, only return new string instances.

Because of that, formatting with an instance method makes little sense, as it would have to be called like:

String formatted = "%s: %s".format(key, value);

The original Java authors (and .NET authors) decided that a static method made more sense in this situation, as you are not modifying the target, but instead calling a format method and passing in an input string.

Here is an example of why format() would be dumb as an instance method. In .NET (and probably in Java), Replace() is an instance method.

You can do this:

 "I Like Wine".Replace("Wine","Beer");

However, nothing happens, because strings are immutable. Replace() tries to return a new string, but it is assigned to nothing.

This causes lots of common rookie mistakes like:

inputText.Replace(" ", "%20");

Again, nothing happens, instead you have to do:

inputText = inputText.Replace(" ","%20");

Now, if you understand that strings are immutable, that makes perfect sense. If you don't, then you are just confused. The proper place for Replace() would be where format() is, as a static method of String:

 inputText = String.Replace(inputText, " ", "%20");

Now there is no question as to what's going on.

The real question is, why did the authors of these frameworks decide that one should be an instance method, and the other static? In my opinion, both are more elegantly expressed as static methods.

Regardless of your opinion, the truth is that you are less prone to make a mistake using the static version, and the code is easier to understand (No Hidden Gotchas).

Of course there are some methods that are perfect as instance methods, take String.Length()

int length = "123".Length();

In this situation, it's obvious we are not trying to modify "123", we are just inspecting it, and returning its length. This is a perfect candidate for an instance method.

My simple rules for Instance Methods on Immutable Objects:

  • If you need to return a new instance of the same type, use a static method.
  • Otherwise, use an instance method.

100% width table overflowing div container

update your CSS to the following: this should fix

.page {
    width: 280px;
    border:solid 1px blue;
    overflow-x: auto;
}

React - Display loading screen while DOM is rendering?

This will happen before ReactDOM.render() takes control of the root <div>. I.e. your App will not have been mounted up to that point.

So you can add your loader in your index.html file inside the root <div>. And that will be visible on the screen until React takes over.

You can use whatever loader element works best for you (svg with animation for example).

You don't need to remove it on any lifecycle method. React will replace any children of its root <div> with your rendered <App/>, as we can see in the GIF below.

Example on CodeSandbox

enter image description here

index.html

<head>
  <style>
    .svgLoader {
      animation: spin 0.5s linear infinite;
      margin: auto;
    }
    .divLoader {
      width: 100vw;
      height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    @keyframes spin {
      0% { transform: rotate(0deg); }
      100% { transform: rotate(360deg); }
    }
  </style>
</head>

<body>
  <div id="root">
    <div class="divLoader">
      <svg class="svgLoader" viewBox="0 0 1024 1024" width="10em" height="10em">
        <path fill="lightblue"
          d="PATH FOR THE LOADER ICON"
        />
      </svg>
    </div>
  </div>
</body>

index.js

Using debugger to inspect the page before ReactDOM.render() runs.

import React from "react";
import ReactDOM from "react-dom";
import "./styles.css";

function App() {
  return (
    <div className="App">
      <h1>Hello CodeSandbox</h1>
      <h2>Start editing to see some magic happen!</h2>
    </div>
  );
}

debugger; // TO INSPECT THE PAGE BEFORE 1ST RENDER

const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);

How to redirect and append both stdout and stderr to a file with Bash?

In Bash you can also explicitly specify your redirects to different files:

cmd >log.out 2>log_error.out

Appending would be:

cmd >>log.out 2>>log_error.out

Rounding to 2 decimal places in SQL

Try using the COLUMN command with the FORMAT option for that:

COLUMN COLUMN_NAME FORMAT 99.99
SELECT COLUMN_NAME FROM ....

Cannot find Dumpbin.exe

Visual Studio Commmunity 2017 - dumpbin.exe became available once I installed the C++ profiling tools in Modify menu from the Visual Studio Installer.

enter image description here

Webdriver Screenshot

TakeScreenShot screenshot=new TakeScreenShot();
screenshot.screenShot("screenshots//TestScreenshot//password.png");

it will work , please try.

How to Execute stored procedure from SQL Plus?

You forgot to put z as an bind variable.

The following EXECUTE command runs a PL/SQL statement that references a stored procedure:

SQL> EXECUTE -
> :Z := EMP_SALE.HIRE('JACK','MANAGER','JONES',2990,'SALES')

Note that the value returned by the stored procedure is being return into :Z

Scripting Language vs Programming Language

If we see logically programming language and scripting language so this is 99.09% same . because we use same concept like loop , control condition ,variable and all so we can say yes both are same but there is only one thing is different between them that is in C/C++ and other programming language we compile the code before execution . but in the PHP , JavaScript and other scripting language we don't need to compile we directly execute in the browser.

Thanks Nitish K. Jha

What does LPCWSTR stand for and how should it be handled with?

LPCWSTR is equivalent to wchar_t const *. It's a pointer to a wide character string that won't be modified by the function call.

You can assign to LPCWSTRs by prepending a L to a string literal: LPCWSTR *myStr = L"Hello World";

LPCTSTR and any other T types, take a string type depending on the Unicode settings for your project. If _UNICODE is defined for your project, the use of T types is the same as the wide character forms, otherwise the Ansi forms. The appropriate function will also be called this way: FindWindowEx is defined as FindWindowExA or FindWindowExW depending on this definition.

@ variables in Ruby on Rails

Use @title in your controllers when you want your variable to be available in your views.

The explanation is that @title is an instance variable while title is a local variable. Rails makes instance variables from controllers available to views because the template code (erb, haml, etc) is executed within the scope of the current controller instance.

UILabel Align Text to center

For Swift 3 it's:

label.textAlignment = .center

How to see if an object is an array without using reflection?

One can access each element of an array separately using the following code:

Object o=...;
if ( o.getClass().isArray() ) {
    for(int i=0; i<Array.getLength(o); i++){
        System.out.println(Array.get(o, i));
    }
}

Notice that it is unnecessary to know what kind of underlying array it is, as this will work for any array.

ERROR in Cannot find module 'node-sass'

I met same issue installing node-sass when I am on Node 12.9.0

Once switching to Node 10.19.0, the issue is gone.

Reference: https://github.com/sass/node-sass/issues/2632

Way to get all alphabetic chars in an array in PHP?

$alphabets = range('A', 'Z');
    $doubleAlphabets = array();
    $count = 0;
    foreach($alphabets as $key => $alphabet)
    {
        $count++;
        $letter = $alphabet;
        while ($letter <= 'Z') 
        {
            $doubleAlphabets[] = $letter;

            ++$letter;
        }
    }

    return $doubleAlphabets;

Convert NSArray to NSString in Objective-C

One approach would be to iterate over the array, calling the description message on each item:

NSMutableString * result = [[NSMutableString alloc] init];
for (NSObject * obj in array)
{
    [result appendString:[obj description]];
}
NSLog(@"The concatenated string is %@", result);

Another approach would be to do something based on each item's class:

NSMutableString * result = [[NSMutableString alloc] init];
for (NSObject * obj in array)
{
    if ([obj isKindOfClass:[NSNumber class]])
    {
        // append something
    }
    else
    {
        [result appendString:[obj description]];
    }
}
NSLog(@"The concatenated string is %@", result);

If you want commas and other extraneous information, you can just do:

NSString * result = [array description];

What are the differences between the BLOB and TEXT datatypes in MySQL?

A BLOB is a binary string to hold a variable amount of data. For the most part BLOB's are used to hold the actual image binary instead of the path and file info. Text is for large amounts of string characters. Normally a blog or news article would constitute to a TEXT field

L in this case is used stating the storage requirement. (Length|Size + 3) as long as it is less than 224.

Reference: http://dev.mysql.com/doc/refman/5.0/en/blob.html

How to reverse a 'rails generate'

You can undo a rails generate in the following ways:

  • For the model: rails destroy MODEL
  • For the controller: rails destroy controller_name

How to copy file from one location to another location?

Copy a file from one location to another location means,need to copy the whole content to another location.Files.copy(Path source, Path target, CopyOption... options) throws IOException this method expects source location which is original file location and target location which is a new folder location with destination same type file(as original). Either Target location needs to exist in our system otherwise we need to create a folder location and then in that folder location we need to create a file with the same name as original filename.Then using copy function we can easily copy a file from one location to other.

 public static void main(String[] args) throws IOException {
                String destFolderPath = "D:/TestFile/abc";
                String fileName = "pqr.xlsx";
                String sourceFilePath= "D:/TestFile/xyz.xlsx";
                File f = new File(destFolderPath);
                if(f.mkdir()){
                    System.out.println("Directory created!!!!");
                }
                else {
                    System.out.println("Directory Exists!!!!");
                }
                f= new File(destFolderPath,fileName);
                if(f.createNewFile())   {

                    System.out.println("File Created!!!!");
                }   else {
                    System.out.println("File exists!!!!");
                }

                Files.copy(Paths.get(sourceFilePath), Paths.get(destFolderPath, fileName),REPLACE_EXISTING);
                System.out.println("Copy done!!!!!!!!!!!!!!");


            }

When do we need curly braces around shell variables?

Curly braces are always needed for accessing array elements and carrying out brace expansion.

It's good to be not over-cautious and use {} for shell variable expansion even when there is no scope for ambiguity.

For example:

dir=log
prog=foo
path=/var/${dir}/${prog}      # excessive use of {}, not needed since / can't be a part of a shell variable name
logfile=${path}/${prog}.log   # same as above, . can't be a part of a shell variable name
path_copy=${path}             # {} is totally unnecessary
archive=${logfile}_arch       # {} is needed since _ can be a part of shell variable name

So, it is better to write the three lines as:

path=/var/$dir/$prog
logfile=$path/$prog.log
path_copy=$path

which is definitely more readable.

Since a variable name can't start with a digit, shell doesn't need {} around numbered variables (like $1, $2 etc.) unless such expansion is followed by a digit. That's too subtle and it does make to explicitly use {} in such contexts:

set app      # set $1 to app
fruit=$1le   # sets fruit to apple, but confusing
fruit=${1}le # sets fruit to apple, makes the intention clear

See:

How do I protect javascript files?

Google Closure Compiler, YUI compressor, Minify, /Packer/... etc, are options for compressing/obfuscating your JS codes. But none of them can help you from hiding your code from the users.

Anyone with decent knowledge can easily decode/de-obfuscate your code using tools like JS Beautifier. You name it.

So the answer is, you can always make your code harder to read/decode, but for sure there is no way to hide.

CSS3 transition events

If you simply want to detect only a single transition end, without using any JS framework here's a little convenient utility function:

function once = function(object,event,callback){
    var handle={};

    var eventNames=event.split(" ");

    var cbWrapper=function(){
        eventNames.forEach(function(e){
            object.removeEventListener(e,cbWrapper, false );
        });
        callback.apply(this,arguments);
    };

    eventNames.forEach(function(e){
        object.addEventListener(e,cbWrapper,false);
    });

    handle.cancel=function(){
        eventNames.forEach(function(e){
            object.removeEventListener(e,cbWrapper, false );
        });
    };

    return handle;
};

Usage:

var handler = once(document.querySelector('#myElement'), 'transitionend', function(){
   //do something
});

then if you wish to cancel at some point you can still do it with

handler.cancel();

It's good for other event usages as well :)

C++ Matrix Class

There is no "canonical" way to do the matrix in C++, STL does not provide classes like "matrix". However there are some 3rd party libraries that do. You are encouraged to use them or write your own implementation. You can try my implementation derived from some public implementation found on the internet.

Python-equivalent of short-form "if" in C++

While a = 'foo' if True else 'bar' is the more modern way of doing the ternary if statement (python 2.5+), a 1-to-1 equivalent of your version might be:

a = (b == True and "123" or "456" )

... which in python should be shortened to:

a = b is True and "123" or "456"

... or if you simply want to test the truthfulness of b's value in general...

a = b and "123" or "456"

? : can literally be swapped out for and or

How to center text vertically with a large font-awesome icon?

Well, this question was asked years ago. I think technology has changed quite a bit and browser compatibility is much better. You could use vertical-align but I would consider that some what less scaleable and less reusable. I would recommend a flexbox approach.

Here is the same example the original poster used but with flexbox. It styles a single element. If a button size changes for whatever reason, it will continue to be vertically and horizontally centered.

.button {
    border: 1px solid #ccc;
    height: 40px;
    margin: 60px;
    padding: 4px;
    display: flex;
    justify-content: space-around;
    align-items: center;
}

Example: JsFiddle

Cross-browser bookmark/add to favorites JavaScript

function bookmark(title, url) {
  if (window.sidebar) { 
    // Firefox
    window.sidebar.addPanel(title, url, '');
  } 
  else if (window.opera && window.print) 
  { 
    // Opera
    var elem = document.createElement('a');
    elem.setAttribute('href', url);
    elem.setAttribute('title', title);
    elem.setAttribute('rel', 'sidebar');
    elem.click(); //this.title=document.title;
  } 
  else if (document.all) 
  { 
    // ie
    window.external.AddFavorite(url, title);
  }
}

I used this & works great in IE, FF, Netscape. Chrome, Opera and safari do not support it!

Sending data from HTML form to a Python script in Flask

The form tag needs some attributes set:

  1. action: The URL that the form data is sent to on submit. Generate it with url_for. It can be omitted if the same URL handles showing the form and processing the data.
  2. method="post": Submits the data as form data with the POST method. If not given, or explicitly set to get, the data is submitted in the query string (request.args) with the GET method instead.
  3. enctype="multipart/form-data": When the form contains file inputs, it must have this encoding set, otherwise the files will not be uploaded and Flask won't see them.

The input tag needs a name parameter.

Add a view to handle the submitted data, which is in request.form under the same key as the input's name. Any file inputs will be in request.files.

@app.route('/handle_data', methods=['POST'])
def handle_data():
    projectpath = request.form['projectFilepath']
    # your code
    # return a response

Set the form's action to that view's URL using url_for:

<form action="{{ url_for('handle_data') }}" method="post">
    <input type="text" name="projectFilepath">
    <input type="submit">
</form>

CSS background-image-opacity?

Try this

<div style="background: linear-gradient( rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7) ), url(/image.png);background-repeat: no-repeat; background-position: center;"> </div>

Converting milliseconds to a date (jQuery/JavaScript)

Try this one :

var time = new Date().toJSON();

How to get just the date part of getdate()?

SELECT CAST(FLOOR(CAST(GETDATE() AS float)) as datetime)

or

SELECT CONVERT(datetime,FLOOR(CONVERT(float,GETDATE())))

How to store a dataframe using Pandas

The easiest way is to pickle it using to_pickle:

df.to_pickle(file_name)  # where to save it, usually as a .pkl

Then you can load it back using:

df = pd.read_pickle(file_name)

Note: before 0.11.1 save and load were the only way to do this (they are now deprecated in favor of to_pickle and read_pickle respectively).


Another popular choice is to use HDF5 (pytables) which offers very fast access times for large datasets:

import pandas as pd
store = pd.HDFStore('store.h5')

store['df'] = df  # save it
store['df']  # load it

More advanced strategies are discussed in the cookbook.


Since 0.13 there's also msgpack which may be be better for interoperability, as a faster alternative to JSON, or if you have python object/text-heavy data (see this question).

How can I get the number of days between 2 dates in Oracle 11g?

I figured it out myself. I need

select extract(day from sysdate - to_date('2009-10-01', 'yyyy-mm-dd')) from dual

How to find prime numbers between 0 - 100?

public static void main(String[] args) {
    int m = 100;
    int a[] =new int[m];
    for (int i=2; i<m; i++)
        for (int j=0; j<m; j+=i)
            a[j]++;
    for (int i=0; i<m; i++)
        if (a[i]==1) System.out.println(i);
}

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

Use:

SELECT *
  FROM YOUR_TABLE
 WHERE creation_date <= TRUNC(SYSDATE) - 30

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

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

SELECT *
  FROM YOUR_TABLE
 WHERE creation_date <= ADD_MONTHS(TRUNC(SYSDATE), -1)

Best way to store password in database

As a key-hardened salted hash, using a secure algorithm such as sha-512.

yii2 redirect in controller action does not work?

In Yii2 we need to return() the result from the action.I think you need to add a return in front of your redirect.

  return $this->redirect(['user/index']);

Python Graph Library

Also, you might want to take a look at NetworkX

trying to align html button at the center of the my page

You can center a button without using text-align on the parent div by simple using margin:auto; display:block;

For example:

HTML

<div>
  <button>Submit</button>
</div>

CSS

button {
  margin:auto;
  display:block;
}

SEE IT IN ACTION: CodePen

How do I compile the asm generated by GCC?

Yes, You can use gcc to compile your asm code. Use -c for compilation like this:

gcc -c file.S -o file.o

This will give object code file named file.o. To invoke linker perform following after above command:

gcc file.o -o file

How can I close a dropdown on click outside?

ELEGANT METHOD

I found this clickOut directive: https://github.com/chliebel/angular2-click-outside. I check it and it works well (i only copy clickOutside.directive.ts to my project). U can use it in this way:

<div (clickOutside)="close($event)"></div>

Where close is your function which will be call when user click outside div. It is very elegant way to handle problem described in question.

If you use above directive to close popUp window, remember first to add event.stopPropagation() to button click event handler which open popUp.

BONUS:

Below i copy oryginal directive code from file clickOutside.directive.ts (in case if link will stop working in future) - the author is Christian Liebel :

_x000D_
_x000D_
import {Directive, ElementRef, Output, EventEmitter, HostListener} from '@angular/core';_x000D_
    _x000D_
@Directive({_x000D_
    selector: '[clickOutside]'_x000D_
})_x000D_
export class ClickOutsideDirective {_x000D_
    constructor(private _elementRef: ElementRef) {_x000D_
    }_x000D_
_x000D_
    @Output()_x000D_
    public clickOutside = new EventEmitter<MouseEvent>();_x000D_
_x000D_
    @HostListener('document:click', ['$event', '$event.target'])_x000D_
    public onClick(event: MouseEvent, targetElement: HTMLElement): void {_x000D_
        if (!targetElement) {_x000D_
            return;_x000D_
        }_x000D_
_x000D_
        const clickedInside = this._elementRef.nativeElement.contains(targetElement);_x000D_
        if (!clickedInside) {_x000D_
            this.clickOutside.emit(event);_x000D_
        }_x000D_
    }_x000D_
}
_x000D_
_x000D_
_x000D_

Solution to "subquery returns more than 1 row" error

use MAX in your SELECT to return on value.. EXAMPLE

INSERT INTO school_year_studentid (student_id,syr_id) VALUES
((SELECT MAX(student_id) FROM student), (SELECT MAX(syr_id) FROM school_year))

instead of

INSERT INTO school_year_studentid (student_id,syr_id) VALUES
((SELECT (student_id) FROM student), (SELECT (syr_id) FROM school_year))

try it without MAX it will more than one value

Creating JSON on the fly with JObject

Simple way of creating newtonsoft JObject from Properties.

This is a Sample User Properties

public class User
{
    public string Name;
    public string MobileNo;
    public string Address;
}

and i want this property in newtonsoft JObject is:

JObject obj = JObject.FromObject(new User()
{
    Name = "Manjunath",
    MobileNo = "9876543210",
    Address = "Mumbai, Maharashtra, India",
});

Output will be like this:

{"Name":"Manjunath","MobileNo":"9876543210","Address":"Mumbai, Maharashtra, India"}

How to write and save html file in python?

As others have mentioned, use triple quotes ”””abc””” for multiline strings. Also, you can do this without having to call close() using the with keyword. For example:

# HTML String
html = """
<table border=1>
     <tr>
       <th>Number</th>
       <th>Square</th>
     </tr>
     <indent>
     <% for i in range(10): %>
       <tr>
         <td><%= i %></td>
         <td><%= i**2 %></td>
       </tr>
     </indent>
</table>
"""

# Write HTML String to file.html
with open("file.html", "w") as file:
    file.write(html)

See https://stackoverflow.com/a/11783672/2206251 for more details on the with keyword in Python.

pip install failing with: OSError: [Errno 13] Permission denied on directory

You are trying to install a package on the system-wide path without having the permission to do so.

  1. In general, you can use sudo to temporarily obtain superuser permissions at your responsibility in order to install the package on the system-wide path:

     sudo pip install -r requirements.txt
    

    Find more about sudo here.

    Actually, this is a bad idea and there's no good use case for it, see @wim's comment.

  2. If you don't want to make system-wide changes, you can install the package on your per-user path using the --user flag.

    All it takes is:

     pip install --user runloop requirements.txt
    
  3. Finally, for even finer grained control, you can also use a virtualenv, which might be the superior solution for a development environment, especially if you are working on multiple projects and want to keep track of each one's dependencies.

    After activating your virtualenv with

    $ my-virtualenv/bin/activate

    the following command will install the package inside the virtualenv (and not on the system-wide path):

    pip install -r requirements.txt

Fill remaining vertical space - only CSS

You can use CSS Flexbox instead another display value, The Flexbox Layout (Flexible Box) module aims at providing a more efficient way to lay out, align and distribute space among items in a container, even when their size is unknown and/or dynamic.

Example

/* CONTAINER */
#wrapper
{
   width:300px;
   height:300px;
    display: -webkit-box; /* OLD - iOS 6-, Safari 3.1-6 */
    display: -moz-box; /* OLD - Firefox 19- (buggy but mostly works) */
    display: -ms-flexbox; /* TWEENER - IE 10 */
    display: -webkit-flex; /* NEW - Chrome */
    display: flex; /* NEW, Spec - Opera 12.1, Firefox 20+ */
    -ms-flex-direction: column;
    -moz-flex-direction: column;
    -webkit-flex-direction: column;
    flex-direction: column;
}

/* SOME ITEM CHILD ELEMENTS */
#first
{
   width:300px;
    height: 200px;
   background-color:#F5DEB3;

}

#second
{
   width:300px;
   background-color: #9ACD32;
    -webkit-box-flex: 1; /* OLD - iOS 6-, Safari 3.1-6 */
    -moz-box-flex: 1; /* OLD - Firefox 19- */
    -webkit-flex: 1; /* Chrome */
    -ms-flex: 1; /* IE 10 */
    flex: 1; /* NEW, */
}

jsfiddle Example

If you want to have full support for old browsers like IE9 or below, you will have to use a polyfills like flexy, this polyfill enable support for Flexbox model but only for 2012 spec of flexbox model.

Recently I found another polyfill to help you with Internet Explorer 8 & 9 or any older browser that not have support for flexbox model, I still have not tried it but I leave the link here

You can find a usefull and complete Guide to Flexbox model by Chris Coyer here

How do I ignore all files in a folder with a Git repository in Sourcetree?

In Sourcetree: Just ignore a file in specified folder. Sourcetree will ask if you like to ignore all files in that folder. It's perfect!

What's the purpose of META-INF?

The META-INF folder is the home for the MANIFEST.MF file. This file contains meta data about the contents of the JAR. For example, there is an entry called Main-Class that specifies the name of the Java class with the static main() for executable JAR files.

php form action php self

This is Perfect. try this one :)

<form name="test" method="post" enctype="multipart/form-data" action="<?php echo $_SERVER['PHP_SELF']; ?>">
/* Html Input Fields */
</form>  

Git ignore file for Xcode projects

I included these suggestions in a Gist I created on Github: http://gist.github.com/137348

Feel free to fork it, and make it better.

Access Control Origin Header error using Axios in React Web throwing error in Chrome

Using the Access-Control-Allow-Origin header to the request won't help you in that case while this header can only be used on the response...

To make it work you should probably add this header to your response.You can also try to add the header crossorigin:true to your request.

Lumen: get URL parameter in a Blade view

Laravel 5.8

{{ request()->a }}

Error in strings.xml file in Android

1. for error: unescaped apostrophe in string

what I found is that AAPT2 tool points to wrong row in xml, sometimes. So you should correct whole strings.xml file

In Android Studio, in problem file use :

Edit->find->replace

Then write in first field \' (or \&,>,\<,\")
in second put '(or &,>,<,")
then replace each if needed.(or "reptlace all" in case with ')
Then in first field again put '(or &,>,<,")
and in second write \'
then replace each if needed.(or "replace all" in case with ')

2. for other problematic symbols
I use to comment each next half part +rebuild until i won't find the wrong sign.

E.g. an escaped word "\update" unexpectedly drops such error :)

IsNullOrEmpty with Object

Why would you need any other way? Comparing an Object reference with null is the least-verbose way to check if it's null.

How to use executeReader() method to retrieve the value of just one cell

It is not recommended to use DataReader and Command.ExecuteReader to get just one value from the database. Instead, you should use Command.ExecuteScalar as following:

String sql = "SELECT ColumnNumber FROM learer WHERE learer.id = " + index;
SqlCommand cmd = new SqlCommand(sql,conn);
learerLabel.Text = (String) cmd.ExecuteScalar();

Here is more information about Connecting to database and managing data.

What is the backslash character (\\)?

\ is used for escape sequences in programming languages.

\n prints a newline
\\ prints a backslash
\" prints "
\t prints a tabulator
\b moves the cursor one back

Floating Div Over An Image

Never fails, once I post the question to SO, I get some enlightening "aha" moment and figure it out. The solution:

_x000D_
_x000D_
    .container {_x000D_
       border: 1px solid #DDDDDD;_x000D_
       width: 200px;_x000D_
       height: 200px;_x000D_
       position: relative;_x000D_
    }_x000D_
    .tag {_x000D_
       float: left;_x000D_
       position: absolute;_x000D_
       left: 0px;_x000D_
       top: 0px;_x000D_
       z-index: 1000;_x000D_
       background-color: #92AD40;_x000D_
       padding: 5px;_x000D_
       color: #FFFFFF;_x000D_
       font-weight: bold;_x000D_
    }
_x000D_
<div class="container">_x000D_
       <div class="tag">Featured</div>_x000D_
       <img src="http://www.placehold.it/200x200">_x000D_
</div>
_x000D_
_x000D_
_x000D_

The key is the container has to be positioned relative and the tag positioned absolute.

How to make a parent div auto size to the width of its children divs

Your interior <div> elements should likely both be float:left. Divs size to 100% the size of their container width automatically. Try using display:inline-block instead of width:auto on the container div. Or possibly float:left the container and also apply overflow:auto. Depends on what you're after exactly.

Passing variables in remote ssh command

Escape the variable in order to access variables outside of the ssh session: ssh [email protected] "~/tools/myScript.pl \$BUILD_NUMBER"

What is an opaque response, and what purpose does it serve?

Consider the case in which a service worker acts as an agnostic cache. Your only goal is serve the same resources that you would get from the network, but faster. Of course you can't ensure all the resources will be part of your origin (consider libraries served from CDNs, for instance). As the service worker has the potential of altering network responses, you need to guarantee you are not interested in the contents of the response, nor on its headers, nor even on the result. You're only interested on the response as a black box to possibly cache it and serve it faster.

This is what { mode: 'no-cors' } was made for.

Presto SQL - Converting a date string to date format

Use: cast(date_parse(inv.date_created,'%Y-%m-%d %h24:%i:%s') as date)

Input: String timestamp

Output: date format 'yyyy-mm-dd'

How to insert close button in popover for Bootstrap

Just wanted to update the answer. As per Swashata Ghosh, the following is a simpler way that worked for moi:

HTML:

<button type="button" class="btn btn-primary example">Example</button>

JS:

$('.example').popover({
   title: function() {
      return 'Popup title' +
             '<button class="close">&times</button>';
   },
   content: 'Popup content',
   trigger: 'hover',
   html: true
});

$('.popover button.close').click(function() {
   $(this).popover('toggle');
});

python, sort descending dataframe with pandas

Edit: This is out of date, see @Merlin's answer.

[False], being a nonempty list, is not the same as False. You should write:

test = df.sort('one', ascending=False)

How to set the From email address for mailx command?

Just ran into this syntax problem on a CentOS 7 machine.

On a very old Ubuntu machine running mail, the syntax for a nicely composed email is

echo -e "$body" | mail -s "$subject" -a "From: Sender Name <$sender>" "$recipient"

However on a CentOS 7 box which came with mailx installed, it's quite different:

echo -e "$body" | mail -s "$subject" -S "from=Sender Name <$sender>" "$recipient"

Consulting man mail indicates that -r is deprecated and the 'From' sender address should now be set directly using -S "variable=value".

In these and subsequent examples, I'm defining $sender as "Sender Name <[email protected]>" and $recipients as "[email protected]" as I do in my bash script.

You may then find, as I did, that when you try to generate the email's body content in your script at the point of sending the email, you encounter a strange behaviour where the email body is instead attached as a binary file ("ATT00001.bin", "application/octet-stream" or "noname", depending on client).

This behaviour is how Heirloom mailx handles unrecognised / control characters in text input. (More info: https://access.redhat.com/solutions/1136493, which itself references the mailx man page for the solution.)

To get around this, I used a method which pipes the generated output through tr before passing to mail, and also specifies the charset of the email:

echo -e "$body" | tr -d \\r | mail -s "$subject" -S "from=$sender" -S "sendcharsets=utf-8,iso-8859-1" "$recipients"

In my script, I'm also explicitly delaring the locale beforehand as it's run as a cronjob (and cron doesn't inherit environmental variables):

LANG="en_GB.UTF8" ; export LANG ;

(An alternate method of setting locales for cronjobs is discussed here)

More info on these workarounds via https://stackoverflow.com/a/29826988/253139 and https://stackoverflow.com/a/3120227/253139.

Java Timestamp - How can I create a Timestamp with the date 23/09/2007?

You could also do the following:

// untested
Calendar cal = GregorianCalendar.getInstance();
cal.set(Calendar.DAY_OF_MONTH, 23);// I might have the wrong Calendar constant...
cal.set(Calendar.MONTH, 8);// -1 as month is zero-based
cal.set(Calendar.YEAR, 2009);
Timestamp tstamp = new Timestamp(cal.getTimeInMillis());

get path for my .exe

in visualstudio 2008 you could use this code :

   var _assembly = System.Reflection.Assembly
               .GetExecutingAssembly().GetName().CodeBase;

   var _path = System.IO.Path.GetDirectoryName(_assembly) ;

How to kill an Android activity when leaving it so that it cannot be accessed from the back button?

Add this attribute to you activity in manifest file. android:noHistory="true"

How do I concatenate two text files in PowerShell?

I used:

Get-Content c:\FileToAppend_*.log | Out-File -FilePath C:\DestinationFile.log 
-Encoding ASCII -Append

This appended fine. I added the ASCII encoding to remove the nul characters Notepad++ was showing without the explicit encoding.

Why should I use var instead of a type?

As the others have said, there is no difference in the compiled code (IL) when you use either of the following:

var x1 = new object();
object x2 = new object;

I suppose Resharper warns you because it is [in my opinion] easier to read the first example than the second. Besides, what's the need to repeat the name of the type twice?

Consider the following and you'll get what I mean:

KeyValuePair<string, KeyValuePair<string, int>> y1 = new KeyValuePair<string, KeyValuePair<string, int>>("key", new KeyValuePair<string, int>("subkey", 5));

It's way easier to read this instead:

var y2 = new KeyValuePair<string, KeyValuePair<string, int>>("key", new KeyValuePair<string, int>("subkey", 5));

How to overwrite the output directory in spark

UPDATE: Suggest using Dataframes, plus something like ... .write.mode(SaveMode.Overwrite) ....

Handy pimp:

implicit class PimpedStringRDD(rdd: RDD[String]) {
    def write(p: String)(implicit ss: SparkSession): Unit = {
      import ss.implicits._
      rdd.toDF().as[String].write.mode(SaveMode.Overwrite).text(p)
    }
  }

For older versions try

yourSparkConf.set("spark.hadoop.validateOutputSpecs", "false")
val sc = SparkContext(yourSparkConf)

In 1.1.0 you can set conf settings using the spark-submit script with the --conf flag.

WARNING (older versions): According to @piggybox there is a bug in Spark where it will only overwrite files it needs to to write it's part- files, any other files will be left unremoved.

Sending SOAP request using Python Requests

It is indeed possible.

Here is an example calling the Weather SOAP Service using plain requests lib:

import requests
url="http://wsf.cdyne.com/WeatherWS/Weather.asmx?WSDL"
#headers = {'content-type': 'application/soap+xml'}
headers = {'content-type': 'text/xml'}
body = """<?xml version="1.0" encoding="UTF-8"?>
         <SOAP-ENV:Envelope xmlns:ns0="http://ws.cdyne.com/WeatherWS/" xmlns:ns1="http://schemas.xmlsoap.org/soap/envelope/" 
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
            <SOAP-ENV:Header/>
              <ns1:Body><ns0:GetWeatherInformation/></ns1:Body>
         </SOAP-ENV:Envelope>"""

response = requests.post(url,data=body,headers=headers)
print response.content

Some notes:

  • The headers are important. Most SOAP requests will not work without the correct headers. application/soap+xml is probably the more correct header to use (but the weatherservice prefers text/xml
  • This will return the response as a string of xml - you would then need to parse that xml.
  • For simplicity I have included the request as plain text. But best practise would be to store this as a template, then you can load it using jinja2 (for example) - and also pass in variables.

For example:

from jinja2 import Environment, PackageLoader
env = Environment(loader=PackageLoader('myapp', 'templates'))
template = env.get_template('soaprequests/WeatherSericeRequest.xml')
body = template.render()

Some people have mentioned the suds library. Suds is probably the more correct way to be interacting with SOAP, but I often find that it panics a little when you have WDSLs that are badly formed (which, TBH, is more likely than not when you're dealing with an institution that still uses SOAP ;) ).

You can do the above with suds like so:

from suds.client import Client
url="http://wsf.cdyne.com/WeatherWS/Weather.asmx?WSDL"
client = Client(url)
print client ## shows the details of this service

result = client.service.GetWeatherInformation() 
print result 

Note: when using suds, you will almost always end up needing to use the doctor!

Finally, a little bonus for debugging SOAP; TCPdump is your friend. On Mac, you can run TCPdump like so:

sudo tcpdump -As 0 

This can be helpful for inspecting the requests that actually go over the wire.

The above two code snippets are also available as gists:

PHP Notice: Undefined offset: 1 with array when reading data

This is a "PHP Notice", so you could in theory ignore it. Change php.ini:

error_reporting = E_ALL & ~E_NOTICE & ~E_STRICT & ~E_DEPRECATED

To

error_reporting = E_ALL & ~E_NOTICE

This show all errors, except for notices.

How to change Apache Tomcat web server port number

You need to edit the Tomcat/conf/server.xml and change the connector port. The connector setting should look something like this:

<Connector port="8080" maxHttpHeaderSize="8192"
           maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
           enableLookups="false" redirectPort="8443" acceptCount="100"
           connectionTimeout="20000" disableUploadTimeout="true" />

Just change the connector port from default 8080 to another valid port number.

Converting string "true" / "false" to boolean value

You could simply have: var result = (str == "true").

How can I generate random number in specific range in Android?

int min = 65;
int max = 80;

Random r = new Random();
int i1 = r.nextInt(max - min + 1) + min;

Note that nextInt(int max) returns an int between 0 inclusive and max exclusive. Hence the +1.

Conda environments not showing up in Jupyter Notebook

Possible Channel-Specific Issue

I had this issue (again) and it turned out I installed from the conda-forge channel; removing it and reinstalling from anaconda channel instead fixed it for me.

Update: I again had the same problem with a new env, this time I did install nb_conda_kernels from anaconda channel, but my jupyter_client was from the conda-forge channel. Uninstalling nb_conda_kernels and reinstalling updated that to a higher-priority channel.

So make sure you've installed from the correct channels :)

How to ignore SSL certificate errors in Apache HttpClient 4.0

For the record, tested with httpclient 4.3.6 and compatible with Executor of fluent api:

CloseableHttpClient httpClient = HttpClients.custom().
                    setHostnameVerifier(new AllowAllHostnameVerifier()).
                    setSslcontext(new SSLContextBuilder().loadTrustMaterial(null, new TrustStrategy()
                    {
                        public boolean isTrusted(X509Certificate[] arg0, String arg1) throws CertificateException
                        {
                            return true;
                        }
                    }).build()).build();

Problems with Android Fragment back stack

If you are Struggling with addToBackStack() & popBackStack() then simply use

FragmentTransaction ft =getSupportFragmentManager().beginTransaction();
ft.replace(R.id.content_frame, new HomeFragment(), "Home");
ft.commit();`

In your Activity In OnBackPressed() find out fargment by tag and then do your stuff

Fragment home = getSupportFragmentManager().findFragmentByTag("Home");

if (home instanceof HomeFragment && home.isVisible()) {
    // do you stuff
}

For more Information https://github.com/DattaHujare/NavigationDrawer I never use addToBackStack() for handling fragment.

Python pip install fails: invalid command egg_info

pip install -U setuptools and easy_install was putting egg-info in the wrong directory.

Then I just reinstalled apt-get install python-dev. Let me install the drivers I want after that

How to set RelativeLayout layout params in code not in xml?

I hope the below code will help. It will create an EditText and a Log In button. Both placed relatively. All done in MainActivity.java.

package com.example.atul.allison;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.RelativeLayout;
import android.widget.Button;
import android.graphics.Color;
import android.widget.EditText;
import android.content.res.Resources;
import android.util.TypedValue;     
    public class MainActivity extends AppCompatActivity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            //Layout
            RelativeLayout atulsLayout = new RelativeLayout(this);
            atulsLayout.setBackgroundColor(Color.GREEN);

            //Button
            Button redButton = new Button(this);
            redButton.setText("Log In");
            redButton.setBackgroundColor(Color.RED);

            //Username input
            EditText username =  new EditText(this);

            redButton.setId(1);
            username.setId(2);

            RelativeLayout.LayoutParams buttonDetails= new RelativeLayout.LayoutParams(
                    RelativeLayout.LayoutParams.WRAP_CONTENT,
                    RelativeLayout.LayoutParams.WRAP_CONTENT
            );

            RelativeLayout.LayoutParams usernameDetails= new RelativeLayout.LayoutParams(
                    RelativeLayout.LayoutParams.WRAP_CONTENT,
                    RelativeLayout.LayoutParams.WRAP_CONTENT
            );

            //give rules to position widgets
            usernameDetails.addRule(RelativeLayout.ABOVE,redButton.getId());
            usernameDetails.addRule(RelativeLayout.CENTER_HORIZONTAL);
            usernameDetails.setMargins(0,0,0,50);

            buttonDetails.addRule(RelativeLayout.CENTER_HORIZONTAL);
            buttonDetails.addRule(RelativeLayout.CENTER_VERTICAL);

            Resources r = getResources();
            int px = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 200,r.getDisplayMetrics());
            username.setWidth(px);

            //Add widget to layout(button is now a child of layout)
            atulsLayout.addView(redButton,buttonDetails);
            atulsLayout.addView(username,usernameDetails);

            //Set these activities content/display to this view
            setContentView(atulsLayout);
        }
    }

Perl: function to trim string leading and trailing whitespace

Here's one approach using a regular expression:

$string =~ s/^\s+|\s+$//g ;     # remove both leading and trailing whitespace

Perl 6 will include a trim function:

$string .= trim;

Source: Wikipedia

Prevent flex items from overflowing a container

If you want the overflow to wrap: flex-flow: row wrap

Erase the current printed console line

Usually when you have a '\r' at the end of the string, only carriage return is printed without any newline. If you have the following:

printf("fooooo\r");
printf("bar");

the output will be:

barooo

One thing I can suggest (maybe a workaround) is to have a NULL terminated fixed size string that is initialized to all space characters, ending in a '\r' (every time before printing), and then use strcpy to copy your string into it (without the newline), so every subsequent print will overwrite the previous string. Something like this:

char str[MAX_LENGTH];        
// init str to all spaces, NULL terminated with character as '\r'
strcpy(str, my_string);       // copy my_string into str
str[strlen(my_string)] = ' '; // erase null termination char
str[MAX_LENGTH - 1] = '\r';
printf(str);

You can do error checking so that my_string is always atleast one less in length than str, but you get the basic idea.

Call angularjs function using jquery/javascript

Please check this answer

// In angularJS script
$scope.foo = function() {
    console.log('test');
};
$window.angFoo = function() {
    $scope.foo();
    $scope.$apply(); 
};
    
// In jQuery
if (window.angFoo) {
    window.angFoo();
}

How to compare two colors for similarity/difference

A color value has more than one dimension, so there is no intrinsic way to compare two colors. You have to determine for your use case the meaning of the colors and thereby how to best compare them.

Most likely you want to compare the hue, saturation and/or lightness properties of the colors as oppposed to the red/green/blue components. If you are having trouble figuring out how you want to compare them, take some pairs of sample colors and compare them mentally, then try to justify/explain to yourself why they are similar/different.

Once you know which properties/components of the colors you want to compare, then you need to figure out how to extract that information from a color.

Most likely you will just need to convert the color from the common RedGreenBlue representation to HueSaturationLightness, and then calculate something like

avghue = (color1.hue + color2.hue)/2
distance = abs(color1.hue-avghue)

This example would give you a simple scalar value indicating how far the gradient/hue of the colors are from each other.

See HSL and HSV at Wikipedia.

How do I align a label and a textarea?

Try setting a height on your td elements.

vertical-align: middle; 

means the element the style is applied to will be aligned within the parent element. The height of the td may be only as high as the text inside.

Twitter Bootstrap - borders

Another solution I ran across tonight, which worked for my needs, was to add box-sizing attributes:

-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
box-sizing: border-box;

These attributes force the border to be part of the box model's width and height and correct the issue as well.

According to caniuse.com » box-sizing, box-sizing is supported in IE8+.

If you're using LESS or Sass there is a Bootstrap mixin for this.

LESS:

.box-sizing(border-box);

Sass:

@include box-sizing(border-box);

Is it possible to listen to a "style change" event?

Just adding and formalizing @David 's solution from above:

Note that jQuery functions are chainable and return 'this' so that multiple invocations can be called one after the other (e.g $container.css("overflow", "hidden").css("outline", 0);).

So the improved code should be:

(function() {
    var ev = new $.Event('style'),
        orig = $.fn.css;
    $.fn.css = function() {
        var ret = orig.apply(this, arguments);
        $(this).trigger(ev);
        return ret; // must include this
    }
})();

Swift: Display HTML data in a label or textView

Add this extension to convert your html code to a regular string:

    extension String {

        var html2AttributedString: NSAttributedString? {
            guard
                let data = dataUsingEncoding(NSUTF8StringEncoding)
            else { return nil }
            do {
                return try NSAttributedString(data: data, options: [NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType,NSCharacterEncodingDocumentAttribute:NSUTF8StringEncoding], documentAttributes: nil)
            } catch let error as NSError {
                print(error.localizedDescription)
                return  nil
            }
        }
        var html2String: String {
            return html2AttributedString?.string ?? ""
        }
}

And then you show your String inside an UITextView Or UILabel

textView.text = yourString.html2String or

label.text = yourString.html2String

How to pass extra variables in URL with WordPress

add following code in function.php

add_filter( 'query_vars', 'addnew_query_vars', 10, 1 );
function addnew_query_vars($vars)
{   
    $vars[] = 'var1'; // var1 is the name of variable you want to add       
    return $vars;
}

then you will b able to use $_GET['var1']

Using the "animated circle" in an ImageView while loading stuff

This is generally referred to as an Indeterminate Progress Bar or Indeterminate Progress Dialog.

Combine this with a Thread and a Handler to get exactly what you want. There are a number of examples on how to do this via Google or right here on SO. I would highly recommend spending the time to learn how to use this combination of classes to perform a task like this. It is incredibly useful across many types of applications and will give you a great insight into how Threads and Handlers can work together.

I'll get you started on how this works:

The loading event starts the dialog:

//maybe in onCreate
showDialog(MY_LOADING_DIALOG);
fooThread = new FooThread(handler);
fooThread.start();

Now the thread does the work:

private class FooThread extends Thread {
    Handler mHandler;

    FooThread(Handler h) {
        mHandler = h;
    }

    public void run() { 
        //Do all my work here....you might need a loop for this

        Message msg = mHandler.obtainMessage();
        Bundle b = new Bundle();                
        b.putInt("state", 1);   
        msg.setData(b);
        mHandler.sendMessage(msg);
    }
}

Finally get the state back from the thread when it is complete:

final Handler handler = new Handler() {
    public void handleMessage(Message msg) {
        int state = msg.getData().getInt("state");
        if (state == 1){
            dismissDialog(MY_LOADING_DIALOG);
            removeDialog(MY_LOADING_DIALOG);
        }
    }
};

Best way to center a <div> on a page vertically and horizontally?

Solution

Using only two lines of CSS, utilizing the magical power of Flexbox

.parent { display: flex; }
.child { margin: auto }

How to printf uint64_t? Fails with: "spurious trailing ‘%’ in format"

When compiling memcached under Centos 5.x i got the same problem.

The solution is to upgrade gcc and g++ to version 4.4 at least.

Make sure your CC/CXX is set (exported) to right binaries before compiling.

Is a GUID unique 100% of the time?

In a more general sense, this is known as the "birthday problem" or "birthday paradox". Wikipedia has a pretty good overview at: Wikipedia - Birthday Problem

In very rough terms, the square root of the size of the pool is a rough approximation of when you can expect a 50% chance of a duplicate. The article includes a probability table of pool size and various probabilities, including a row for 2^128. So for a 1% probability of collision you would expect to randomly pick 2.6*10^18 128-bit numbers. A 50% chance requires 2.2*10^19 picks, while SQRT(2^128) is 1.8*10^19.

Of course, that is just the ideal case of a truly random process. As others mentioned, a lot is riding on the that random aspect - just how good is the generator and seed? It would be nice if there was some hardware support to assist with this process which would be more bullet-proof except that anything can be spoofed or virtualized. I suspect that might be the reason why MAC addresses/time-stamps are no longer incorporated.

How to stop an animation (cancel() does not work)

To stop animation you may set such objectAnimator that do nothing, e.g.

first when manual flipping there is animation left to right:

flipper.setInAnimation(leftIn);
flipper.setOutAnimation(rightOut);

then when switching to auto flipping there's no animation

flipper.setInAnimation(doNothing);
flipper.setOutAnimation(doNothing);

doNothing = ObjectAnimator.ofFloat(flipper, "x", 0f, 0f).setDuration(flipperSwipingDuration);

What is the difference between LATERAL and a subquery in PostgreSQL?

What is a LATERAL join?

The feature was introduced with PostgreSQL 9.3.
Quoting the manual:

Subqueries appearing in FROM can be preceded by the key word LATERAL. This allows them to reference columns provided by preceding FROM items. (Without LATERAL, each subquery is evaluated independently and so cannot cross-reference any other FROM item.)

Table functions appearing in FROM can also be preceded by the key word LATERAL, but for functions the key word is optional; the function's arguments can contain references to columns provided by preceding FROM items in any case.

Basic code examples are given there.

More like a correlated subquery

A LATERAL join is more like a correlated subquery, not a plain subquery, in that expressions to the right of a LATERAL join are evaluated once for each row left of it - just like a correlated subquery - while a plain subquery (table expression) is evaluated once only. (The query planner has ways to optimize performance for either, though.)
Related answer with code examples for both side by side, solving the same problem:

For returning more than one column, a LATERAL join is typically simpler, cleaner and faster.
Also, remember that the equivalent of a correlated subquery is LEFT JOIN LATERAL ... ON true:

Things a subquery can't do

There are things that a LATERAL join can do, but a (correlated) subquery cannot (easily). A correlated subquery can only return a single value, not multiple columns and not multiple rows - with the exception of bare function calls (which multiply result rows if they return multiple rows). But even certain set-returning functions are only allowed in the FROM clause. Like unnest() with multiple parameters in Postgres 9.4 or later. The manual:

This is only allowed in the FROM clause;

So this works, but cannot (easily) be replaced with a subquery:

CREATE TABLE tbl (a1 int[], a2 int[]);
SELECT * FROM tbl, unnest(a1, a2) u(elem1, elem2);  -- implicit LATERAL

The comma (,) in the FROM clause is short notation for CROSS JOIN.
LATERAL is assumed automatically for table functions.
About the special case of UNNEST( array_expression [, ... ] ):

Set-returning functions in the SELECT list

You can also use set-returning functions like unnest() in the SELECT list directly. This used to exhibit surprising behavior with more than one such function in the same SELECT list up to Postgres 9.6. But it has finally been sanitized with Postgres 10 and is a valid alternative now (even if not standard SQL). See:

Building on above example:

SELECT *, unnest(a1) AS elem1, unnest(a2) AS elem2
FROM   tbl;

Comparison:

dbfiddle for pg 9.6 here
dbfiddle for pg 10 here

Clarify misinformation

The manual:

For the INNER and OUTER join types, a join condition must be specified, namely exactly one of NATURAL, ON join_condition, or USING (join_column [, ...]). See below for the meaning.
For CROSS JOIN, none of these clauses can appear.

So these two queries are valid (even if not particularly useful):

SELECT *
FROM   tbl t
LEFT   JOIN LATERAL (SELECT * FROM b WHERE b.t_id = t.t_id) t ON TRUE;

SELECT *
FROM   tbl t, LATERAL (SELECT * FROM b WHERE b.t_id = t.t_id) t;

While this one is not:

SELECT *
FROM   tbl t
LEFT   JOIN LATERAL (SELECT * FROM b WHERE b.t_id = t.t_id) t;

That's why Andomar's code example is correct (the CROSS JOIN does not require a join condition) and Attila's is was not.

How to check empty object in angular 2 template using *ngIf

This should do what you want:

<div class="comeBack_up" *ngIf="(previous_info | json) != ({} | json)">

or shorter

<div class="comeBack_up" *ngIf="(previous_info | json) != '{}'">

Each {} creates a new instance and ==== comparison of different objects instances always results in false. When they are convert to strings === results to true

Plunker example

How can I run multiple npm scripts in parallel?

A better solution is to use &

"dev": "npm run start-watch & npm run wp-server"

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

For the Germans:

you have to change your decimal commas into a Full stop in your csv-file (in Excel:File -> Options -> Advanced -> "Decimal seperator") , then the error is solved.

get next and previous day with PHP

Very easy with the dateTime() object, too.

$tomorrow = new DateTime('tomorrow');
echo $tomorrow->format("Y-m-d"); // Tomorrow's date

$yesterday = new DateTime('yesterday');
echo $yesterday->format("Y-m-d"); // Yesterday's date

How to make a simple modal pop up form using jquery and html?

I came across this question when I was trying similar things.

A very nice and simple sample is presented at w3schools website.

https://www.w3schools.com/bootstrap/tryit.asp?filename=trybs_modal&stacked=h

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_x000D_
<!DOCTYPE html>_x000D_
<html lang="en">_x000D_
<head>_x000D_
  <title>Bootstrap Example</title>_x000D_
  <meta charset="utf-8">_x000D_
  <meta name="viewport" content="width=device-width, initial-scale=1">_x000D_
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">_x000D_
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>_x000D_
</head>_x000D_
<body>_x000D_
_x000D_
<div class="container">_x000D_
  <h2>Modal Example</h2>_x000D_
  <!-- Trigger the modal with a button -->_x000D_
  <button type="button" class="btn btn-info btn-lg" data-toggle="modal" data-target="#myModal">Open Modal</button>_x000D_
_x000D_
  <!-- Modal -->_x000D_
  <div class="modal fade" id="myModal" role="dialog">_x000D_
    <div class="modal-dialog">_x000D_
    _x000D_
      <!-- Modal content-->_x000D_
      <div class="modal-content">_x000D_
        <div class="modal-header">_x000D_
          <button type="button" class="close" data-dismiss="modal">&times;</button>_x000D_
          <h4 class="modal-title">Modal Header</h4>_x000D_
        </div>_x000D_
        <div class="modal-body">_x000D_
          <p>Some text in the modal.</p>_x000D_
        </div>_x000D_
        <div class="modal-footer">_x000D_
          <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>_x000D_
        </div>_x000D_
      </div>_x000D_
      _x000D_
    </div>_x000D_
  </div>_x000D_
  _x000D_
</div>_x000D_
_x000D_
</body>_x000D_
</html>
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Could not resolve this reference. Could not locate the assembly

Maybe it will help someone, but sometimes Name tag might be missing for a reference and it leads that assembly cannot be found when building with MSBuild. Make sure that Name tag is available for particular reference csproj file, for example,

    <ProjectReference Include="..\MyDependency1.csproj">
      <Project>{9A2D95B3-63B0-4D53-91F1-5EFB99B22FE8}</Project>
      <Name>MyDependency1</Name>
    </ProjectReference>

How to delete a file after checking whether it exists

If you want to avoid a DirectoryNotFoundException you will need to ensure that the directory of the file does indeed exist. File.Exists accomplishes this. Another way would be to utilize the Path and Directory utility classes like so:

string file = @"C:\subfolder\test.txt";
if (Directory.Exists(Path.GetDirectoryName(file)))
{
    File.Delete(file);
}

How to delete an element from an array in C#

Balabaster's answer is correct if you want to remove all instances of the element. If you want to remove only the first one, you would do something like this:

int[] numbers = { 1, 3, 4, 9, 2, 4 };
int numToRemove = 4;
int firstFoundIndex = Array.IndexOf(numbers, numToRemove);
if (numbers >= 0)
{
    numbers = numbers.Take(firstFoundIndex).Concat(numbers.Skip(firstFoundIndex + 1)).ToArray();
}

How do I add a linker or compile flag in a CMake file?

You can also add linker flags to a specific target using the LINK_FLAGS property:

set_property(TARGET ${target} APPEND_STRING PROPERTY LINK_FLAGS " ${flag}")

If you want to propagate this change to other targets, you can create a dummy target to link to.

Hide axis values but keep axis tick labels in matplotlib

Not sure this is the best way, but you can certainly replace the tick labels like this:

import matplotlib.pyplot as plt
x = range(10)
y = range(10)
plt.plot(x,y)
plt.xticks(x," ")
plt.show()

In Python 3.4 this generates a simple line plot with no tick labels on the x-axis. A simple example is here: http://matplotlib.org/examples/ticks_and_spines/ticklabels_demo_rotation.html

This related question also has some better suggestions: Hiding axis text in matplotlib plots

I'm new to python. Your mileage may vary in earlier versions. Maybe others can help?

How to find the highest value of a column in a data frame in R?

Similar to colMeans, colSums, etc, you could write a column maximum function, colMax, and a column sort function, colSort.

colMax <- function(data) sapply(data, max, na.rm = TRUE)
colSort <- function(data, ...) sapply(data, sort, ...)

I use ... in the second function in hopes of sparking your intrigue.

Get your data:

dat <- read.table(h=T, text = "Ozone Solar.R Wind Temp Month Day
1     41     190  7.4   67     5   1
2     36     118  8.0   72     5   2
3     12     149 12.6   74     5   3
4     18     313 11.5   62     5   4
5     NA      NA 14.3   56     5   5
6     28      NA 14.9   66     5   6
7     23     299  8.6   65     5   7
8     19      99 13.8   59     5   8
9      8      19 20.1   61     5   9")

Use colMax function on sample data:

colMax(dat)
#  Ozone Solar.R    Wind    Temp   Month     Day 
#   41.0   313.0    20.1    74.0     5.0     9.0

To do the sorting on a single column,

sort(dat$Solar.R, decreasing = TRUE)
# [1] 313 299 190 149 118  99  19

and over all columns use our colSort function,

colSort(dat, decreasing = TRUE) ## compare with '...' above

Prevent content from expanding grid items

The existing answers solve most cases. However, I ran into a case where I needed the content of the grid-cell to be overflow: visible. I solved it by absolutely positioning within a wrapper (not ideal, but the best I know), like this:


.month-grid {
  display: grid;
  grid-template: repeat(6, 1fr) / repeat(7, 1fr);
  background: #fff;
  grid-gap: 2px;  
}

.day-item-wrapper {
  position: relative;
}

.day-item {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 10px;

  background: rgba(0,0,0,0.1);
}

https://codepen.io/bjnsn/pen/vYYVPZv

Using jquery to delete all elements with a given id

if you want to remove all elements with matching ID parts, for example:

<span id='myID_123'>
<span id='myID_456'>
<span id='myID_789'>

try this:

$("span[id*=myID]").remove();

don't forget the '*' - this will remove them all at once - cheers

Working Demo

How do you set EditText to only accept numeric values in Android?

the simplest for me

android:numeric="integer" 

although this also more customize

android:digits="0123456789"

How can Perl's print add a newline by default?

You can use the -l option in the she-bang header:

#!/usr/bin/perl -l

$text = "hello";

print $text;
print $text;

Output:

hello
hello

What is the maximum length of a valid email address?

320

And the segments look like this

{64}@{255}

64 + 1 + 255 = 320

You should also read this if you are validating emails

http://haacked.com/archive/2007/08/21/i-knew-how-to-validate-an-email-address-until-i.aspx

How to do Base64 encoding in node.js?

I am using following code to decode base64 string in node API nodejs version 10.7.0

let data = 'c3RhY2thYnVzZS5jb20=';  // Base64 string
let buff = new Buffer(data, 'base64');  //Buffer
let text = buff.toString('ascii');  //this is the data type that you want your Base64 data to convert to
console.log('"' + data + '" converted from Base64 to ASCII is "' + text + '"'); 

Please don't try to run above code in console of the browser, won't work. Put the code in server side files of nodejs. I am using above line code in API development.

Java - JPA - @Version annotation

Version used to ensure that only one update in a time. JPA provider will check the version, if the expected version already increase then someone else already update the entity so an exception will be thrown.

So updating entity value would be more secure, more optimist.

If the value changes frequent, then you might consider not to use version field. For an example "an entity that has counter field, that will increased everytime a web page accessed"

REST API Best practices: Where to put parameters?

There are no hard and fast rules, but the rule of thumb from a purely conceptual standpoint that I like to use can briefly be summed up like this: a URI path (by definition) represents a resource and query parameters are essentially modifiers on that resource. So far that likely doesn't help... With a REST API you have the major methods of acting upon a single resource using GET, PUT, and DELETE . Therefore whether something should be represented in the path or as a parameter can be reduced to whether those methods make sense for the representation in question. Would you reasonably PUT something at that path and would it be semantically sound to do so? You could of course PUT something just about anywhere and bend the back-end to handle it, but you should be PUTing what amounts to a representation of the actual resource and not some needlessly contextualized version of it. For collections the same can be done with POST. If you wanted to add to a particular collection what would be a URL that makes sense to POST to.

This still leaves some gray areas as some paths could point to what amount to children of parent resources which is somewhat discretionary and dependent on their use. The one hard line that this draws is that any type of transitive representation should be done using a query parameter, since it would not have an underlying resource.

In response to the real world example given in the original question (Twitter's API), the parameters represent a transitive query that filters on the state of the resources (rather than a hierarchy). In that particular example it would be entirely unreasonable to add to the collection represented by those constraints, and further that query would not be able to be represented as a path that would make any sense in the terms of an object graph.

The adoption of this type of resource oriented perspective can easily map directly to the object graph of your domain model and drive the logic of your API to the point where everything works very cleanly and in a fairly self-documenting way once it snaps into clarity. The concept can also be made clearer by stepping away from systems that use traditional URL routing mapped on to a normally ill-fitting data model (i.e. an RDBMS). Apache Sling would certainly be a good place to start. The concept of object traversal dispatch in a system like Zope also provides a clearer analog.

ffprobe or avprobe not found. Please install one

  • Update your version of youtube-dl to the lastest as older version might not support.

     pip install --upgrade youtube_dl
    
  • Install 'ffmpeg' and 'ffprobe' module

     pip install ffmpeg
     pip install ffprobe
    
  • If you face the same issue, then download ffmpeg builds and put all the .exe files to Script folder($path: "Python\Python38-32\Scripts") (Windows OS only)

When should I use the Visitor Design Pattern?

The reason for your confusion is probably that the Visitor is a fatal misnomer. Many (prominent1!) programmers have stumbled over this problem. What it actually does is implement double dispatching in languages that don't support it natively (most of them don't).


1) My favourite example is Scott Meyers, acclaimed author of “Effective C++”, who called this one of his most important C++ aha! moments ever.

One command to create a directory and file inside it linux command

you can install the script ;

pip3 install --user advance-touch

After installed, you can use ad command

ad airport/plane/captain.txt
airport/
+-- plane/
¦   +-- captain.txt

How to allow access outside localhost

A quick solution that might help someone :

Add this line as value for start ng serve --host 0.0.0.0 --disable-host-check in your package.json

ex:

{
"ng": "ng",
"start": "ng serve --host 0.0.0.0 --disable-host-check",
"build": "ng build",
}

And then simply do start or npm run start

you will be able to access your project from other local IPs.

How to set combobox default value?

Suppose you bound your combobox to a List<Person>

List<Person> pp = new List<Person>();
pp.Add(new Person() {id = 1, name="Steve"});
pp.Add(new Person() {id = 2, name="Mark"});
pp.Add(new Person() {id = 3, name="Charles"});

cbo1.DisplayMember = "name";
cbo1.ValueMember = "id";
cbo1.DataSource = pp;

At this point you cannot set the Text property as you like, but instead you need to add an item to your list before setting the datasource

pp.Insert(0, new Person() {id=-1, name="--SELECT--"});
cbo1.DisplayMember = "name";
cbo1.ValueMember = "id";
cbo1.DataSource = pp;
cbo1.SelectedIndex = 0;

Of course this means that you need to add a checking code when you try to use the info from the combobox

if(cbo1.SelectedValue != null && Convert.ToInt32(cbo1.SelectedValue) == -1)
    MessageBox.Show("Please select a person name");
else
    ...... 

The code is the same if you use a DataTable instead of a list. You need to add a fake row at the first position of the Rows collection of the datatable and set the initial index of the combobox to make things clear. The only thing you need to look at are the name of the datatable columns and which columns should contain a non null value before adding the row to the collection

In a table with three columns like ID, FirstName, LastName with ID,FirstName and LastName required you need to

DataRow row = datatable.NewRow();
row["ID"] = -1;
row["FirstName"] = "--Select--";    
row["LastName"] = "FakeAddress";
dataTable.Rows.InsertAt(row, 0);

What is the use of the %n format specifier in C?

I haven't really seen many practical real world uses of the %n specifier, but I remember that it was used in oldschool printf vulnerabilities with a format string attack quite a while back.

Something that went like this

void authorizeUser( char * username, char * password){

    ...code here setting authorized to false...
    printf(username);

    if ( authorized ) {
         giveControl(username);
    }
}

where a malicious user could take advantage of the username parameter getting passed into printf as the format string and use a combination of %d, %c or w/e to go through the call stack and then modify the variable authorized to a true value.

Yeah it's an esoteric use, but always useful to know when writing a daemon to avoid security holes? :D

HTML/CSS Making a textbox with text that is grayed out, and disappears when I click to enter info, how?

Here's a one-liner slim way for layering text on top of an input in jQuery using ES6 syntax.

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_x000D_
$('.input-group > input').focus(e => $(e.currentTarget).parent().find('.placeholder').hide()).blur(e => { if (!$(e.currentTarget).val()) $(e.currentTarget).parent().find('.placeholder').show(); });
_x000D_
* {
  font-family: sans-serif;
}

.input-group {
  position: relative;
}

.input-group > input {
  width: 150px;
  padding: 10px 0px 10px 25px;
}

.input-group > .placeholder {
  position: absolute;
  top: 50%;
  left: 25px;
  transform: translateY(-50%);
  color: #929292;
}
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="input-group">
  <span class="placeholder">Username</span>
  <input>
</div>
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_x000D_
_x000D_

"Unable to get the VLookup property of the WorksheetFunction Class" error

I was having the same problem. It seems that passing Me.ComboBox1.Value as an argument for the Vlookup function is causing the issue. What I did was assign this value to a double and then put it into the Vlookup function.

Dim x As Double
x = Me.ComboBox1.Value
Me.TextBox1.Value = Application.WorksheetFunction.VLookup(x, Worksheets("Sheet3").Range("Names"), 2, False) 

Or, for a shorter method, you can just convert the type within the Vlookup function using Cdbl(<Value>).

So it would end up being

Me.TextBox1.Value = Application.WorksheetFunction.VLookup(Cdbl(Me.ComboBox1.Value), Worksheets("Sheet3").Range("Names"), 2, False) 

Strange as it may sound, it works for me.

Hope this helps.

Image convert to Base64

Function convert image to base64 using jquery (you can convert to vanila js). Hope it help to you!

Usage: input is your nameId input has file image

<input type="file" id="asd"/>
<button onclick="proccessData()">Submit</button>

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>

async function converImageToBase64(inputId) {
  let image = $('#'+inputId)[0]['files']

  if (image && image[0]) {
    const reader = new FileReader();

    return new Promise(resolve => {
      reader.onload = ev => {
        resolve(ev.target.result)
      }
      reader.readAsDataURL(image[0])
    })
  }
}

async function proccessData() {
  const image = await converImageToBase64('asd')
  console.log(image)
}

</script>

Example: converImageToBase64('yourFileInputId')

https://codepen.io/mariohandsome/pen/yLadmVb

Rails: How to reference images in CSS within Rails 4

Sprockets together with Sass has some nifty helpers you can use to get the job done. Sprockets will only process these helpers if your stylesheet file extensions are either .css.scss or .css.sass.


Image specific helper:

background-image: image-url("logo.png")

Agnostic helper:

background-image: asset-url("logo.png", image)
background-image: asset-url($asset, $asset-type)

Or if you want to embed the image data in the css file:

background-image: asset-data-url("logo.png")

How can I convert a DOM element to a jQuery element?

What about constructing the element using jQuery? e.g.

$("<div></div>")

creates a new div element, ready to be added to the page. Can be shortened further to

$("<div>")

then you can chain on commands that you need, set up event handlers and append it to the DOM. For example

$('<div id="myid">Div Content</div>')
    .bind('click', function(e) { /* event handler here */ })
    .appendTo('#myOtherDiv');

Angular.js ng-repeat filter by property having one of multiple values (OR of values)

Here is a way to do it while passing in an extra argument:

https://stackoverflow.com/a/17813797/4533488 (thanks to Denis Pshenov)

<div ng-repeat="group in groups">
    <li ng-repeat="friend in friends | filter:weDontLike(group.enemy.name)">
        <span>{{friend.name}}</span>
    <li>
</div>

With the backend:

$scope.weDontLike = function(name) {
    return function(friend) {
        return friend.name != name;
    }
}

.


And yet another way with an in-template filter only:

https://stackoverflow.com/a/12528093/4533488 (thanks to mikel)

<div ng:app>
  <div ng-controller="HelloCntl">
    <ul>
       <li ng-repeat="friend in friends | filter:{name:'!Adam'}">
            <span>{{friend.name}}</span>
            <span>{{friend.phone}}</span>
        </li>
    </ul>
</div>

How do I get the selected element by name and then get the selected value from a dropdown using jQuery?

To add to the answers here, ensure there's no space between the select and [name...

Wrong:

'select [name=' + name + ']'
       ^

Right:

'select[name=' + name + ']'

How to make pylab.savefig() save image for 'maximized' window instead of default size

I had this exact problem and this worked:

plt.savefig(output_dir + '/xyz.png', bbox_inches='tight')

Here is the documentation:

[https://matplotlib.org/3.1.1/api/_as_gen/matplotlib.pyplot.savefig.html][1]

Format Date time in AngularJS

Here are a few popular examples:

<div>{{myDate | date:'M/d/yyyy'}}</div> 7/4/2014

<div>{{myDate | date:'yyyy-MM-dd'}}</div> 2014-07-04

<div>{{myDate | date:'M/d/yyyy HH:mm:ss'}}</div> 7/4/2014 12:01:59

How to fill 100% of remaining height?

To get a div to 100% height on a page, you will need to set each object on the hierarchy above the div to 100% as well. for instance:

html { height:100%; }
body { height:100%; }
#full { height: 100%; }
#someid { height: 100%; }

Although I cannot fully understand your question, I'm assuming this is what you mean.

This is the example I am working from:

<html style="height:100%">
    <body style="height:100%">
        <div style="height:100%; width: 300px;">
            <div style="height:100%; background:blue;">

            </div>
        </div>
    </body>
</html>

Style is just a replacement for the CSS which I haven't externalised.

cell format round and display 2 decimal places

Input: 0 0.1 1000

=FIXED(E5,2)

Output: 0.00 0.10 1,000.00

=TEXT(E5,"0.00")

Output: 0.00 0.10 1000.00

Note: As you can see FIXED add a coma after a thousand, where TEXT does not.

Check if object exists in JavaScript

You could use "typeof".

if(typeof maybeObject != "undefined")
    alert("GOT HERE");

How to get Spinner value?

View view =(View) getActivity().findViewById(controlId);
Spinner spinner = (Spinner)view.findViewById(R.id.spinner1);
String valToSet = spinner.getSelectedItem().toString();

Is there way to use two PHP versions in XAMPP?

Yes you can. I assume you have a xampp already installed. So,

  • Close all xampp instances. Using task manager stop apache and mysqld.
  • Then rename the xampp to xampp1 or something after xampp name.
  • Now Download the other xampp version. Create a folder name xampp only. Install the downloaded xampp there.
  • Now depending on the xampp version of your requirement, just rename the target folder to xampp only and other folder to different name.

That's how I am working with multiple xampp installed

How to store token in Local or Session Storage in Angular 2?

As a general rule, the token should not be stored on the localStorage neither the sessionStorage. Both places are accessible from JS and the JS should not care about the authentication token.

IMHO The token should be stored on a cookie with the HttpOnly and Secure flag as suggested here: https://stormpath.com/blog/where-to-store-your-jwts-cookies-vs-html5-web-storage

Return positions of a regex match() in Javascript?

exec returns an object with a index property:

_x000D_
_x000D_
var match = /bar/.exec("foobar");_x000D_
if (match) {_x000D_
    console.log("match found at " + match.index);_x000D_
}
_x000D_
_x000D_
_x000D_

And for multiple matches:

_x000D_
_x000D_
var re = /bar/g,_x000D_
    str = "foobarfoobar";_x000D_
while ((match = re.exec(str)) != null) {_x000D_
    console.log("match found at " + match.index);_x000D_
}
_x000D_
_x000D_
_x000D_

Change value of variable with dplyr

We can use replace to change the values in 'mpg' to NA that corresponds to cyl==4.

mtcars %>%
     mutate(mpg=replace(mpg, cyl==4, NA)) %>%
     as.data.frame()

The type or namespace name could not be found

Changing the framework to

.NET Framework 4 Client Profile

did the job for me.

Pointer to class data member "::*"

Here is an example where pointer to data members could be useful:

#include <iostream>
#include <list>
#include <string>

template <typename Container, typename T, typename DataPtr>
typename Container::value_type searchByDataMember (const Container& container, const T& t, DataPtr ptr) {
    for (const typename Container::value_type& x : container) {
        if (x->*ptr == t)
            return x;
    }
    return typename Container::value_type{};
}

struct Object {
    int ID, value;
    std::string name;
    Object (int i, int v, const std::string& n) : ID(i), value(v), name(n) {}
};

std::list<Object*> objects { new Object(5,6,"Sam"), new Object(11,7,"Mark"), new Object(9,12,"Rob"),
    new Object(2,11,"Tom"), new Object(15,16,"John") };

int main() {
    const Object* object = searchByDataMember (objects, 11, &Object::value);
    std::cout << object->name << '\n';  // Tom
}

What is the ultimate postal code and zip regex?

We use the following:

Canada

([A-Z]{1}[0-9]{1}){3}   //We raise to upper first

America

[0-9]{5}                //-or-
[0-9]{5}-[0-9]{4}       //10 digit zip

Other

Accept as is

Use JAXB to create Object from XML String

If you already have the xml, and comes more than one attribute, you can handle it as follows:

String output = "<ciudads><ciudad><idCiudad>1</idCiudad>
<nomCiudad>BOGOTA</nomCiudad></ciudad><ciudad><idCiudad>6</idCiudad>
<nomCiudad>Pereira</nomCiudad></ciudads>";
DocumentBuilder db = DocumentBuilderFactory.newInstance()
    .newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(output));

Document doc = db.parse(is);
NodeList nodes = ((org.w3c.dom.Document) doc)
    .getElementsByTagName("ciudad");

for (int i = 0; i < nodes.getLength(); i++) {           
    Ciudad ciudad = new Ciudad();
    Element element = (Element) nodes.item(i);

    NodeList name = element.getElementsByTagName("idCiudad");
    Element element2 = (Element) name.item(0);
    ciudad.setIdCiudad(Integer
        .valueOf(getCharacterDataFromElement(element2)));

    NodeList title = element.getElementsByTagName("nomCiudad");
    element2 = (Element) title.item(0);
    ciudad.setNombre(getCharacterDataFromElement(element2));

    ciudades.getPartnerAccount().add(ciudad);
}
}

for (Ciudad ciudad1 : ciudades.getPartnerAccount()) {
System.out.println(ciudad1.getIdCiudad());
System.out.println(ciudad1.getNombre());
}

the method getCharacterDataFromElement is

public static String getCharacterDataFromElement(Element e) {
Node child = e.getFirstChild();
if (child instanceof CharacterData) {
CharacterData cd = (CharacterData) child;

return cd.getData();
}
return "";
}

In PHP, what is a closure and why does it use the "use" identifier?

Zupa did a great job explaining closures with 'use' and the difference between EarlyBinding and Referencing the variables that are 'used'.

So I made a code example with early binding of a variable (= copying):

<?php

$a = 1;
$b = 2;

$closureExampleEarlyBinding = function() use ($a, $b){
    $a++;
    $b++;
    echo "Inside \$closureExampleEarlyBinding() \$a = ".$a."<br />";
    echo "Inside \$closureExampleEarlyBinding() \$b = ".$b."<br />";    
};

echo "Before executing \$closureExampleEarlyBinding() \$a = ".$a."<br />";
echo "Before executing \$closureExampleEarlyBinding() \$b = ".$b."<br />";  

$closureExampleEarlyBinding();

echo "After executing \$closureExampleEarlyBinding() \$a = ".$a."<br />";
echo "After executing \$closureExampleEarlyBinding() \$b = ".$b."<br />";

/* this will output:
Before executing $closureExampleEarlyBinding() $a = 1
Before executing $closureExampleEarlyBinding() $b = 2
Inside $closureExampleEarlyBinding() $a = 2
Inside $closureExampleEarlyBinding() $b = 3
After executing $closureExampleEarlyBinding() $a = 1
After executing $closureExampleEarlyBinding() $b = 2
*/

?>

Example with referencing a variable (notice the '&' character before variable);

<?php

$a = 1;
$b = 2;

$closureExampleReferencing = function() use (&$a, &$b){
    $a++;
    $b++;
    echo "Inside \$closureExampleReferencing() \$a = ".$a."<br />";
    echo "Inside \$closureExampleReferencing() \$b = ".$b."<br />"; 
};

echo "Before executing \$closureExampleReferencing() \$a = ".$a."<br />";
echo "Before executing \$closureExampleReferencing() \$b = ".$b."<br />";   

$closureExampleReferencing();

echo "After executing \$closureExampleReferencing() \$a = ".$a."<br />";
echo "After executing \$closureExampleReferencing() \$b = ".$b."<br />";    

/* this will output:
Before executing $closureExampleReferencing() $a = 1
Before executing $closureExampleReferencing() $b = 2
Inside $closureExampleReferencing() $a = 2
Inside $closureExampleReferencing() $b = 3
After executing $closureExampleReferencing() $a = 2
After executing $closureExampleReferencing() $b = 3
*/

?>

Append TimeStamp to a File Name

you can use:

Stopwatch.GetTimestamp();

How to serve an image using nodejs

It is too late but helps someone, I'm using node version v7.9.0 and express version 4.15.0

if your directory structure is something like this:

your-project
   uploads
   package.json
   server.js

server.js code:

var express         = require('express');
var app             = express();
app.use(express.static(__dirname + '/uploads'));// you can access image 
 //using this url: http://localhost:7000/abc.jpg
//make sure `abc.jpg` is present in `uploads` dir.

//Or you can change the directory for hiding real directory name:

`app.use('/images', express.static(__dirname+'/uploads/'));// you can access image using this url: http://localhost:7000/images/abc.jpg


app.listen(7000);

Spring MVC: Error 400 The request sent by the client was syntactically incorrect

Your request mapping is /save, but your POST is to /save.html. Changing the POST to /save should fix it.

Applying .gitignore to committed files

After editing .gitignore to match the ignored files, you can do git ls-files -ci --exclude-standard to see the files that are included in the exclude lists; you can then do

  • Linux/MacOS: git ls-files -ci --exclude-standard -z | xargs -0 git rm --cached
  • Windows (PowerShell): git ls-files -ci --exclude-standard | % { git rm --cached "$_" }
  • Windows (cmd.exe): for /F "tokens=*" %a in ('git ls-files -ci --exclude-standard') do @git rm --cached "%a"

to remove them from the repository (without deleting them from disk).

Edit: You can also add this as an alias in your .gitconfig file so you can run it anytime you like. Just add the following line under the [alias] section (modify as needed for Windows or Mac):

apply-gitignore = !git ls-files -ci --exclude-standard -z | xargs -0 git rm --cached

(The -r flag in xargs prevents git rm from running on an empty result and printing out its usage message, but may only be supported by GNU findutils. Other versions of xargs may or may not have a similar option.)

Now you can just type git apply-gitignore in your repo, and it'll do the work for you!

Mapping a JDBC ResultSet to an object

No need of storing resultSet values into String and again setting into POJO class. Instead set at the time you are retrieving.

Or best way switch to ORM tools like hibernate instead of JDBC which maps your POJO object direct to database.

But as of now use this:

List<User> users=new ArrayList<User>();

while(rs.next()) {
   User user = new User();      
   user.setUserId(rs.getString("UserId"));
   user.setFName(rs.getString("FirstName"));
  ...
  ...
  ...


  users.add(user);
} 

A keyboard shortcut to comment/uncomment the select text in Android Studio

From menu, Code -> Comment with Line Commment. So simple. enter image description here

Or, alternatively, add a shortcut as the following: enter image description here

enter image description here

Java List.contains(Object with field value equal to x)

Map

You could create a Hashmap<String, Object> using one of the values as a key, and then seeing if yourHashMap.keySet().contains(yourValue) returns true.

Oracle DB : java.sql.SQLException: Closed Connection

It means the connection was successfully established at some point, but when you tried to commit right there, the connection was no longer open. The parameters you mentioned sound like connection pool settings. If so, they're unrelated to this problem. The most likely cause is a firewall between you and the database that is killing connections after a certain amount of idle time. The most common fix is to make your connection pool run a validation query when a connection is checked out from it. This will immediately identify and evict dead connnections, ensuring that you only get good connections out of the pool.

C++ display stack trace on exception

Since the stack is already unwound when entering the catch block, the solution in my case was to not catch certain exceptions which then lead to a SIGABRT. In the signal handler for SIGABRT I then fork() and execl() either gdb (in debug builds) or Google breakpads stackwalk (in release builds). Also I try to only use signal handler safe functions.

GDB:

static const char BACKTRACE_START[] = "<2>--- backtrace of entire stack ---\n";
static const char BACKTRACE_STOP[] = "<2>--- backtrace finished ---\n";

static char *ltrim(char *s)
{
    while (' ' == *s) {
        s++;
    }
    return s;
}

void Backtracer::print()
{
    int child_pid = ::fork();
    if (child_pid == 0) {
        // redirect stdout to stderr
        ::dup2(2, 1);

        // create buffer for parent pid (2+16+1 spaces to allow up to a 64 bit hex parent pid)
        char pid_buf[32];
        const char* stem = "                   ";
        const char* s = stem;
        char* d = &pid_buf[0];
        while (static_cast<bool>(*s))
        {
            *d++ = *s++;
        }
        *d-- = '\0';
        char* hexppid = d;

        // write parent pid to buffer and prefix with 0x
        int ppid = getppid();
        while (ppid != 0) {
            *hexppid = ((ppid & 0xF) + '0');
            if(*hexppid > '9') {
                *hexppid += 'a' - '0' - 10;
            }
            --hexppid;
            ppid >>= 4;
        }
        *hexppid-- = 'x';
        *hexppid = '0';

        // invoke GDB
        char name_buf[512];
        name_buf[::readlink("/proc/self/exe", &name_buf[0], 511)] = 0;
        ssize_t r = ::write(STDERR_FILENO, &BACKTRACE_START[0], sizeof(BACKTRACE_START));
        (void)r;
        ::execl("/usr/bin/gdb",
                "/usr/bin/gdb", "--batch", "-n", "-ex", "thread apply all bt full", "-ex", "quit",
                &name_buf[0], ltrim(&pid_buf[0]), nullptr);
        ::exit(1); // if GDB failed to start
    } else if (child_pid == -1) {
        ::exit(1); // if forking failed
    } else {
        // make it work for non root users
        if (0 != getuid()) {
            ::prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY, 0, 0, 0);
        }
        ::waitpid(child_pid, nullptr, 0);
        ssize_t r = ::write(STDERR_FILENO, &BACKTRACE_STOP[0], sizeof(BACKTRACE_STOP));
        (void)r;
    }
}

minidump_stackwalk:

static bool dumpCallback(const google_breakpad::MinidumpDescriptor& descriptor, void* context, bool succeeded)
{
    int child_pid = ::fork();
    if (child_pid == 0) {
        ::dup2(open("/dev/null", O_WRONLY), 2); // ignore verbose output on stderr
        ssize_t r = ::write(STDOUT_FILENO, &MINIDUMP_STACKWALK_START[0], sizeof(MINIDUMP_STACKWALK_START));
        (void)r;
        ::execl("/usr/bin/minidump_stackwalk", "/usr/bin/minidump_stackwalk", descriptor.path(), "/usr/share/breakpad-syms", nullptr);
        ::exit(1); // if minidump_stackwalk failed to start
    } else if (child_pid == -1) {
        ::exit(1); // if forking failed
    } else {
        ::waitpid(child_pid, nullptr, 0);
        ssize_t r = ::write(STDOUT_FILENO, &MINIDUMP_STACKWALK_STOP[0], sizeof(MINIDUMP_STACKWALK_STOP));
        (void)r;
    }
    ::remove(descriptor.path()); // this is not signal safe anymore but should still work
    return succeeded;
}

Edit: To make it work for breakpad I also had to add this:

std::set_terminate([]()
{
    ssize_t r = ::write(STDERR_FILENO, EXCEPTION, sizeof(EXCEPTION));
    (void)r;
    google_breakpad::ExceptionHandler::WriteMinidump(std::string("/tmp"), dumpCallback, NULL);
    exit(1); // avoid creating a second dump by not calling std::abort
});

Source: How to get a stack trace for C++ using gcc with line number information? and Is it possible to attach gdb to a crashed process (a.k.a "just-in-time" debugging)

How do I increase the cell width of the Jupyter/ipython notebook in my browser?

To get this to work with jupyter (version 4.0.6) I created ~/.jupyter/custom/custom.css containing:

/* Make the notebook cells take almost all available width */
.container {
    width: 99% !important;
}   

/* Prevent the edit cell highlight box from getting clipped;
 * important so that it also works when cell is in edit mode*/
div.cell.selected {
    border-left-width: 1px !important;
}

browser sessionStorage. share between tabs?

You can use localStorage and its "storage" eventListener to transfer sessionStorage data from one tab to another.

This code would need to exist on ALL tabs. It should execute before your other scripts.

// transfers sessionStorage from one tab to another
var sessionStorage_transfer = function(event) {
  if(!event) { event = window.event; } // ie suq
  if(!event.newValue) return;          // do nothing if no value to work with
  if (event.key == 'getSessionStorage') {
    // another tab asked for the sessionStorage -> send it
    localStorage.setItem('sessionStorage', JSON.stringify(sessionStorage));
    // the other tab should now have it, so we're done with it.
    localStorage.removeItem('sessionStorage'); // <- could do short timeout as well.
  } else if (event.key == 'sessionStorage' && !sessionStorage.length) {
    // another tab sent data <- get it
    var data = JSON.parse(event.newValue);
    for (var key in data) {
      sessionStorage.setItem(key, data[key]);
    }
  }
};

// listen for changes to localStorage
if(window.addEventListener) {
  window.addEventListener("storage", sessionStorage_transfer, false);
} else {
  window.attachEvent("onstorage", sessionStorage_transfer);
};


// Ask other tabs for session storage (this is ONLY to trigger event)
if (!sessionStorage.length) {
  localStorage.setItem('getSessionStorage', 'foobar');
  localStorage.removeItem('getSessionStorage', 'foobar');
};

I tested this in chrome, ff, safari, ie 11, ie 10, ie9

This method "should work in IE8" but i could not test it as my IE was crashing every time i opened a tab.... any tab... on any website. (good ol IE) PS: you'll obviously need to include a JSON shim if you want IE8 support as well. :)

Credit goes to this full article: http://blog.guya.net/2015/06/12/sharing-sessionstorage-between-tabs-for-secure-multi-tab-authentication/

Make the current commit the only (initial) commit in a Git repository?

The method below is exactly reproducible, so there's no need to run clone again if both sides were consistent, just run the script on the other side too.

git log -n1 --format=%H >.git/info/grafts
git filter-branch -f
rm .git/info/grafts

If you then want to clean it up, try this script:

http://sam.nipl.net/b/git-gc-all-ferocious

I wrote a script which "kills history" for each branch in the repository:

http://sam.nipl.net/b/git-kill-history

see also: http://sam.nipl.net/b/confirm

The program can't start because cygwin1.dll is missing... in Eclipse CDT

You can compile with either Cygwin's g++ or MinGW (via stand-alone or using Cygwin package). However, in order to run it, you need to add the Cygwin1.dll (and others) PATH to the system Windows PATH, before any cygwin style paths.

Thus add: ;C:\cygwin64\bin to the end of your Windows system PATH variable.

Also, to compile for use in CMD or PowerShell, you may need to use:

x86_64-w64-mingw32-g++.exe -static -std=c++11 prog_name.cc -o prog_name.exe

(This invokes the cross-compiler, if installed.)

SQL Server equivalent to MySQL enum data type?

CREATE FUNCTION ActionState_Preassigned()
RETURNS tinyint
AS
BEGIN
    RETURN 0
END

GO

CREATE FUNCTION ActionState_Unassigned()
RETURNS tinyint
AS
BEGIN
    RETURN 1
END

-- etc...

Where performance matters, still use the hard values.

Are vectors passed to functions by value or by reference in C++

when we pass vector by value in a function as an argument,it simply creates the copy of vector and no any effect happens on the vector which is defined in main function when we call that particular function. while when we pass vector by reference whatever is written in that particular function, every action will going to perform on the vector which is defined in main or other function when we call that particular function.

How do a send an HTTPS request through a proxy in Java?

Try the Apache Commons HttpClient library instead of trying to roll your own: http://hc.apache.org/httpclient-3.x/index.html

From their sample code:

  HttpClient httpclient = new HttpClient();
  httpclient.getHostConfiguration().setProxy("myproxyhost", 8080);

  /* Optional if authentication is required.
  httpclient.getState().setProxyCredentials("my-proxy-realm", " myproxyhost",
   new UsernamePasswordCredentials("my-proxy-username", "my-proxy-password"));
  */

  PostMethod post = new PostMethod("https://someurl");
  NameValuePair[] data = {
     new NameValuePair("user", "joe"),
     new NameValuePair("password", "bloggs")
  };
  post.setRequestBody(data);
  // execute method and handle any error responses.
  // ...
  InputStream in = post.getResponseBodyAsStream();
  // handle response.


  /* Example for a GET reqeust
  GetMethod httpget = new GetMethod("https://someurl");
  try { 
    httpclient.executeMethod(httpget);
    System.out.println(httpget.getStatusLine());
  } finally {
    httpget.releaseConnection();
  }
  */

How do I cancel a build that is in progress in Visual Studio?

The build context menu has a Cancel build in Visual Studio 2013.

HAX kernel module is not installed

Turning off HyperV on windows 8.1 did the trick for me

dism.exe /Online /Disable-Feature:Microsoft-Hyper-V

How to return a value from pthread threads in C?

I think you have to store the number on heap. The int ret variable was on stack and was destructed at the end of execution of function myThread.

void *myThread()
{
       int *ret = malloc(sizeof(int));
       if (ret == NULL) {
           // ...
       }
       *ret = 42;
       pthread_exit(ret);
}

Don't forget to free it when you don't need it :)

Another solution is to return the number as value of the pointer, like Neil Butterworth suggests.

Bootstrap: Use .pull-right without having to hardcode a negative margin-top

just put #login-box before <h2>Welcome</h2> will be ok.

<div class='container'>
    <div class='hero-unit'>
        <div id='login-box' class='pull-right control-group'>
            <div class='clearfix'>
                <input type='text' placeholder='Username' />
            </div>
            <div class='clearfix'>
                <input type='password' placeholder='Password' />
            </div>
            <button type='button' class='btn btn-primary'>Log in</button>
        </div>
        <h2>Welcome</h2>

        <p>Please log in</p>

    </div>
</div>

here is jsfiddle http://jsfiddle.net/SyjjW/4/

HTTP POST using JSON in Java

For Java 11 you can use new HTTP client:

 HttpClient client = HttpClient.newHttpClient();
    HttpRequest request = HttpRequest.newBuilder()
        .uri(URI.create("http://localhost/api"))
        .header("Content-Type", "application/json")
        .POST(ofInputStream(() -> getClass().getResourceAsStream(
            "/some-data.json")))
        .build();

    client.sendAsync(request, BodyHandlers.ofString())
        .thenApply(HttpResponse::body)
        .thenAccept(System.out::println)
        .join();

You can use publisher from InputStream, String, File. Converting JSON to the String or IS you can with Jackson.

How to yum install Node.JS on Amazon Linux

As others mentioned using epel gives a really outdated version, here is a little script I just wrote instead to add to the CI pipeline or pass it to ec2 user-data to install the latest version of node, simply replace the version with what you want, and the appropriate distro of Linux you are using.

The following example is for amazon-Linux-2-AMI

#!/bin/bash

version='v14.13.1'
distro='linux-x64'
package_name="node-$version-$distro"
package_location="/usr/local/lib/"

curl -O https://nodejs.org/download/release/latest/$package_name.tar.gz
tar -xvf $package_name.tar.gz -C $package_location
rm -rfv $package_name.tar.gz

echo "export PATH=$package_location/$package_name/bin:\$PATH" >> ~/.profile

if you want to test it in the same shell simply run

. ~/.profile

Reset auto increment counter in postgres

Converted from comment for the sake of visitor's convenience

It's not clear from this message what the correct syntax is. It is:

ALTER SEQUENCE product_id_seq RESTART WITH 1453;

multiple conditions for JavaScript .includes() method

That should work even if one, and only one of the conditions is true :

var str = "bonjour le monde vive le javascript";
var arr = ['bonjour','europe', 'c++'];

function contains(target, pattern){
    var value = 0;
    pattern.forEach(function(word){
      value = value + target.includes(word);
    });
    return (value === 1)
}

console.log(contains(str, arr));

Dictionary of dictionaries in Python?

If it is only to add a new tuple and you are sure that there are no collisions in the inner dictionary, you can do this:

def addNameToDictionary(d, tup):
    if tup[0] not in d:
        d[tup[0]] = {}
    d[tup[0]][tup[1]] = [tup[2]]

Finding the median of an unsorted array

The quick select algorithm can find the k-th smallest element of an array in linear (O(n)) running time. Here is an implementation in python:

import random

def partition(L, v):
    smaller = []
    bigger = []
    for val in L:
        if val < v: smaller += [val]
        if val > v: bigger += [val]
    return (smaller, [v], bigger)

def top_k(L, k):
    v = L[random.randrange(len(L))]
    (left, middle, right) = partition(L, v)
    # middle used below (in place of [v]) for clarity
    if len(left) == k:   return left
    if len(left)+1 == k: return left + middle
    if len(left) > k:    return top_k(left, k)
    return left + middle + top_k(right, k - len(left) - len(middle))

def median(L):
    n = len(L)
    l = top_k(L, n / 2 + 1)
    return max(l)

Android: ScrollView vs NestedScrollView

NestedScrollView

NestedScrollView is just like ScrollView, but it supports acting as both a nested scrolling parent and child on both new and old versions of Android. Nested scrolling is enabled by default.

https://developer.android.com/reference/android/support/v4/widget/NestedScrollView.html

ScrollView

Layout container for a view hierarchy that can be scrolled by the user, allowing it to be larger than the physical display. A ScrollView is a FrameLayout, meaning you should place one child in it containing the entire contents to scroll; this child may itself be a layout manager with a complex hierarchy of objects

https://developer.android.com/reference/android/widget/ScrollView.html

twig: IF with multiple conditions

If I recall correctly Twig doesn't support || and && operators, but requires or and and to be used respectively. I'd also use parentheses to denote the two statements more clearly although this isn't technically a requirement.

{%if ( fields | length > 0 ) or ( trans_fields | length > 0 ) %}

Expressions

Expressions can be used in {% blocks %} and ${ expressions }.

Operator    Description
==          Does the left expression equal the right expression?
+           Convert both arguments into a number and add them.
-           Convert both arguments into a number and substract them.
*           Convert both arguments into a number and multiply them.
/           Convert both arguments into a number and divide them.
%           Convert both arguments into a number and calculate the rest of the integer division.
~           Convert both arguments into a string and concatenate them.
or          True if the left or the right expression is true.
and         True if the left and the right expression is true.
not         Negate the expression.

For more complex operations, it may be best to wrap individual expressions in parentheses to avoid confusion:

{% if (foo and bar) or (fizz and (foo + bar == 3)) %}

Parsing XML with namespace in Python via 'ElementTree'

My solution is based on @Martijn Pieters' comment:

register_namespace only influences serialisation, not search.

So the trick here is to use different dictionaries for serialization and for searching.

namespaces = {
    '': 'http://www.example.com/default-schema',
    'spec': 'http://www.example.com/specialized-schema',
}

Now, register all namespaces for parsing and writing:

for name, value in namespaces.iteritems():
    ET.register_namespace(name, value)

For searching (find(), findall(), iterfind()) we need a non-empty prefix. Pass these functions a modified dictionary (here I modify the original dictionary, but this must be made only after the namespaces are registered).

self.namespaces['default'] = self.namespaces['']

Now, the functions from the find() family can be used with the default prefix:

print root.find('default:myelem', namespaces)

but

tree.write(destination)

does not use any prefixes for elements in the default namespace.

How to display Toast in Android?

Inside Fragments (onCreateView)

Toast.makeText(getActivity(), "your message" , Toast.LENGTH_LONG).show();

Inside Classes (onCreate)

Toast.makeText(myClassName.this, "your message" , Toast.LENGTH_LONG).show();

Correct way to handle conditional styling in React

 <div style={{ visibility: this.state.driverDetails.firstName != undefined? 'visible': 'hidden'}}></div>

Checkout the above code. That will do the trick.

How to run Unix shell script from Java code?

I would say that it is not in the spirit of Java to run a shell script from Java. Java is meant to be cross platform, and running a shell script would limit its use to just UNIX.

With that said, it's definitely possible to run a shell script from within Java. You'd use exactly the same syntax you listed (I haven't tried it myself, but try executing the shell script directly, and if that doesn't work, execute the shell itself, passing the script in as a command line parameter).

Possible to restore a backup of SQL Server 2014 on SQL Server 2012?

Sure it's possible... use Export Wizard in source option use SQL SERVER NATIVE CLIENT 11, later your source server ex.192.168.100.65\SQLEXPRESS next step select your new destination server ex.192.168.100.65\SQL2014

Just be sure to be using correct instance and connect each other

Just pay attention in Stored procs must be recompiled

jQuery, get html of a whole element

Differences might not be meaningful in a typical use case, but using the standard DOM functionality

$("#el")[0].outerHTML

is about twice as fast as

$("<div />").append($("#el").clone()).html();

so I would go with:

/* 
 * Return outerHTML for the first element in a jQuery object,
 * or an empty string if the jQuery object is empty;  
 */
jQuery.fn.outerHTML = function() {
   return (this[0]) ? this[0].outerHTML : '';  
};

Proper way to exit command line program?

if you do ctrl-z and then type exit it will close background applications.

Ctrl+Q is another good way to kill the application.

Software Design vs. Software Architecture

Architecture identifies fundamental components of the system, describes their organisation and how they are related to create a framework for the system.

Design describes various components and how they should be developed to provide required functionality with in the framework provided by the system architecture.

Can't use WAMP , port 80 is used by IIS 7.5

goto services and stop the "World Wide Web Publishing Service" after restart the wamp server. after that start the "World Wide Web Publishing Service"

Styling input buttons for iPad and iPhone

-webkit-appearance: none;

Note : use bootstrap to style a button.Its common for responsive.

Inserting a PDF file in LaTeX

Use the pdfpages package.

\usepackage{pdfpages}

To include all the pages in the PDF file:

\includepdf[pages=-]{myfile.pdf}

To include just the first page of a PDF:

\includepdf[pages={1}]{myfile.pdf}

Run texdoc pdfpages in a shell to see the complete manual for pdfpages.

Python3: ImportError: No module named '_ctypes' when using Value from module multiprocessing

I was having the same problem. None of the above solutions worked for me. The key challenge was that I didn't have the root access. So, I first download the source of libffi. Then I compiled it with usual commands:

./configure --prefix=desired_installation_path_to_libffi
make 

Then I recompiled python using

./configure --prefix=/home/user123/Softwares/Python/installation3/  LDFLAGS='-L/home/user123/Softwares/library/libffi/installation/lib64'
make 
make install

In my case, 'home/user123/Softwares/library/libffi/installation/lib64' is path to LIBFFI installation directory where libffi.so is located. And, /home/user123/Softwares/Python/installation3/ is path to Python installation directory. Modify them as per your case.

iOS: present view controller programmatically

LandingScreenViewController *nextView=[self.storyboard instantiateViewControllerWithIdentifier:@"nextView"];
[self presentViewController:nextView animated:YES completion:^{}];

How to fix IndexError: invalid index to scalar variable

In the for, you have an iteration, then for each element of that loop which probably is a scalar, has no index. When each element is an empty array, single variable, or scalar and not a list or array you cannot use indices.

Switch tabs using Selenium WebDriver with Java

driver.findElement(By.cssSelector("body")).sendKeys(Keys.CONTROL,Keys.SHIFT,Keys.TAB);

This method helps in switching between multiple windows. The restricting problem with this method is that it can only be used so many times until the required window is reached. Hope it helps.