Programs & Examples On #Static data

How do I install Composer on a shared hosting?

You can do it that way:

  • Create a directory where you want to install composer (let's say /home/your_username/composer)
  • Go to this directory - cd /home/your_username/composer
  • Then run the following command:

    php -r "readfile('https://getcomposer.org/installer');" | php

  • After that if you want to run composer, you can do it this way (in this caseyou must be in the composer's dir): php composer.phar

  • As a next step, you can do this:

    alias composer="/home/your_username/composer/composer.phar".

    And run commands like you do it normally: $ composer install

Hope that helps

Clearfix with twitter bootstrap

clearfix should contain the floating elements but in your html you have added clearfix only after floating right that is your pull-right so you should do like this:

<div class="clearfix">
  <div id="sidebar">
    <ul>
      <li>A</li>
      <li>A</li>
      <li>C</li>
      <li>D</li>
      <li>E</li>
      <li>F</li>
      <li>...</li>
      <li>Z</li>
    </ul>
  </div>
  <div id="main">
    <div>
      <div class="pull-right">
        <a>RIGHT</a>
      </div>
    </div>
  <div>MOVED BELOW Z</div>
</div>

see this demo


Happy to know you solved the problem by setting overflow properties. However this is also good idea to clear the float. Where you have floated your elements you could add overflow: hidden; as you have done in your main.

Simplest SOAP example

The question is 'What is the simplest SOAP example using Javascript?'

This answer is of an example in the Node.js environment, rather than a browser. (Let's name the script soap-node.js) And we will use the public SOAP web service from Europe PMC as an example to get the reference list of an article.

const XMLHttpRequest = require("xmlhttprequest").XMLHttpRequest;
const DOMParser = require('xmldom').DOMParser;

function parseXml(text) {
    let parser = new DOMParser();
    let xmlDoc = parser.parseFromString(text, "text/xml");
    Array.from(xmlDoc.getElementsByTagName("reference")).forEach(function (item) {
        console.log('Title: ', item.childNodes[3].childNodes[0].nodeValue);
    });

}

function soapRequest(url, payload) {
    let xmlhttp = new XMLHttpRequest();
    xmlhttp.open('POST', url, true);

    // build SOAP request
    xmlhttp.onreadystatechange = function () {
        if (xmlhttp.readyState == 4) {
            if (xmlhttp.status == 200) {
                parseXml(xmlhttp.responseText);
            }
        }
    }

    // Send the POST request
    xmlhttp.setRequestHeader('Content-Type', 'text/xml');
    xmlhttp.send(payload);
}

soapRequest('https://www.ebi.ac.uk/europepmc/webservices/soap', 
    `<?xml version="1.0" encoding="UTF-8"?>
    <S:Envelope xmlns:S="http://schemas.xmlsoap.org/soap/envelope/">
    <S:Header />
    <S:Body>
        <ns4:getReferences xmlns:ns4="http://webservice.cdb.ebi.ac.uk/"
            xmlns:ns2="http://www.scholix.org"
            xmlns:ns3="https://www.europepmc.org/data">
            <id>C7886</id>
            <source>CTX</source>
            <offSet>0</offSet>
            <pageSize>25</pageSize>
            <email>[email protected]</email>
        </ns4:getReferences>
    </S:Body>
    </S:Envelope>`);

Before running the code, you need to install two packages:

npm install xmlhttprequest
npm install xmldom

Now you can run the code:

node soap-node.js

And you'll see the output as below:

Title:  Perspective: Sustaining the big-data ecosystem.
Title:  Making proteomics data accessible and reusable: current state of proteomics databases and repositories.
Title:  ProteomeXchange provides globally coordinated proteomics data submission and dissemination.
Title:  Toward effective software solutions for big biology.
Title:  The NIH Big Data to Knowledge (BD2K) initiative.
Title:  Database resources of the National Center for Biotechnology Information.
Title:  Europe PMC: a full-text literature database for the life sciences and platform for innovation.
Title:  Bio-ontologies-fast and furious.
Title:  BioPortal: ontologies and integrated data resources at the click of a mouse.
Title:  PubMed related articles: a probabilistic topic-based model for content similarity.
Title:  High-Impact Articles-Citations, Downloads, and Altmetric Score.

successful/fail message pop up box after submit?

You are echoing outside the body tag of your HTML. Put your echos there, and you should be fine.

Also, remove the onclick="alert()" from your submit. This is the cause for your first undefined message.

<?php
  $posted = false;
  if( $_POST ) {
    $posted = true;

    // Database stuff here...
    // $result = mysql_query( ... )
    $result = $_POST['name'] == "danny"; // Dummy result
  }
?>

<html>
  <head></head>
  <body>

  <?php
    if( $posted ) {
      if( $result ) 
        echo "<script type='text/javascript'>alert('submitted successfully!')</script>";
      else
        echo "<script type='text/javascript'>alert('failed!')</script>";
    }
  ?>
    <form action="" method="post">
      Name:<input type="text" id="name" name="name"/>
      <input type="submit" value="submit" name="submit"/>
    </form>
  </body>
</html>

Passing a string with spaces as a function argument in bash

Another solution to the issue above is to set each string to a variable, call the function with variables denoted by a literal dollar sign \$. Then in the function use eval to read the variable and output as expected.

#!/usr/bin/ksh

myFunction()
{
  eval string1="$1"
  eval string2="$2"
  eval string3="$3"

  echo "string1 = ${string1}"
  echo "string2 = ${string2}"
  echo "string3 = ${string3}"
}

var1="firstString"
var2="second string with spaces"
var3="thirdString"

myFunction "\${var1}" "\${var2}" "\${var3}"

exit 0

Output is then:

    string1 = firstString
    string2 = second string with spaces
    string3 = thirdString

In trying to solve a similar problem to this, I was running into the issue of UNIX thinking my variables were space delimeted. I was trying to pass a pipe delimited string to a function using awk to set a series of variables later used to create a report. I initially tried the solution posted by ghostdog74 but could not get it to work as not all of my parameters were being passed in quotes. After adding double-quotes to each parameter it then began to function as expected.

Below is the before state of my code and fully functioning after state.

Before - Non Functioning Code

#!/usr/bin/ksh

#*******************************************************************************
# Setup Function To Extract Each Field For The Error Report
#*******************************************************************************
getField(){
  detailedString="$1"
  fieldNumber=$2

  # Retrieves Column ${fieldNumber} From The Pipe Delimited ${detailedString} 
  #   And Strips Leading And Trailing Spaces
  echo ${detailedString} | awk -F '|' -v VAR=${fieldNumber} '{ print $VAR }' | sed 's/^[ \t]*//;s/[ \t]*$//'
}

while read LINE
do
  var1="$LINE"

  # Below Does Not Work Since There Are Not Quotes Around The 3
  iputId=$(getField "${var1}" 3)
done<${someFile}

exit 0

After - Functioning Code

#!/usr/bin/ksh

#*******************************************************************************
# Setup Function To Extract Each Field For The Report
#*******************************************************************************
getField(){
  detailedString="$1"
  fieldNumber=$2

  # Retrieves Column ${fieldNumber} From The Pipe Delimited ${detailedString} 
  #   And Strips Leading And Trailing Spaces
  echo ${detailedString} | awk -F '|' -v VAR=${fieldNumber} '{ print $VAR }' | sed 's/^[ \t]*//;s/[ \t]*$//'
}

while read LINE
do
  var1="$LINE"

  # Below Now Works As There Are Quotes Around The 3
  iputId=$(getField "${var1}" "3")
done<${someFile}

exit 0

How do I declare an array variable in VBA?

Generally, you should declare variables of a specific type, rather than Variant. In this example, the test variable should be of type String.

And, because it's an array, you need to indicate that specifically when you declare the variable. There are two ways of declaring array variables:

  1. If you know the size of the array (the number of elements that it should contain) when you write the program, you can specify that number in parentheses in the declaration:

    Dim test(1) As String   'declares an array with 2 elements that holds strings
    

    This type of array is referred to as a static array, as its size is fixed, or static.

  2. If you do not know the size of the array when you write the application, you can use a dynamic array. A dynamic array is one whose size is not specified in the declaration (Dim statement), but rather is determined later during the execution of the program using the ReDim statement. For example:

    Dim test() As String
    Dim arraySize As Integer
    
    ' Code to do other things, like calculate the size required for the array
    ' ...
    arraySize = 5
    
    ReDim test(arraySize)  'size the array to the value of the arraySize variable
    

How to change the timeout on a .NET WebClient object

In some cases it is necessary to add user agent to headers:

WebClient myWebClient = new WebClient();
myWebClient.DownloadFile(myStringWebResource, fileName);
myWebClient.Headers["User-Agent"] = "Mozilla/4.0 (Compatible; Windows NT 5.1; MSIE 6.0) (compatible; MSIE 6.0; Windows NT 5.1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";

This was the solution to my case.

Credit:

http://genjurosdojo.blogspot.com/2012/10/the-remote-server-returned-error-504.html

How to open a new tab in GNOME Terminal from command line?

For anyone seeking a solution that does not use the command line: ctrl+shift+t

No resource found that matches the given name '@style/ Theme.Holo.Light.DarkActionBar'

The @android did not work for me. When I use android (without the @) it works like a charm.

Example:

<style name="CustomActionBarTheme"
       parent="android:style/Theme.Holo.Light.DarkActionBar">

iOS: How to store username/password within an app?

A very easy solution via Keychains.

It's a simple wrapper for the system Keychain. Just add the SSKeychain.h, SSKeychain.m, SSKeychainQuery.h and SSKeychainQuery.m files to your project and add the Security.framework to your target.

To save a password:

[SSKeychain setPassword:@"AnyPassword" forService:@"AnyService" account:@"AnyUser"]

To retrieve a password:

NSString *password = [SSKeychain passwordForService:@"AnyService" account:@"AnyUser"];

Where setPassword is what value you want saved and forService is what variable you want it saved under and account is for what user/object the password and any other info is for.

How to get a list of column names

If you are using the command line shell to SQLite then .headers on before you perform your query. You only need to do this once in a given session.

How can I use numpy.correlate to do autocorrelation?

Your question 1 has been already extensively discussed in several excellent answers here.

I thought to share with you a few lines of code that allow you to compute the autocorrelation of a signal based only on the mathematical properties of the autocorrelation. That is, the autocorrelation may be computed in the following way:

  1. subtract the mean from the signal and obtain an unbiased signal

  2. compute the Fourier transform of the unbiased signal

  3. compute the power spectral density of the signal, by taking the square norm of each value of the Fourier transform of the unbiased signal

  4. compute the inverse Fourier transform of the power spectral density

  5. normalize the inverse Fourier transform of the power spectral density by the sum of the squares of the unbiased signal, and take only half of the resulting vector

The code to do this is the following:

def autocorrelation (x) :
    """
    Compute the autocorrelation of the signal, based on the properties of the
    power spectral density of the signal.
    """
    xp = x-np.mean(x)
    f = np.fft.fft(xp)
    p = np.array([np.real(v)**2+np.imag(v)**2 for v in f])
    pi = np.fft.ifft(p)
    return np.real(pi)[:x.size/2]/np.sum(xp**2)

Bootstrap 4, how to make a col have a height of 100%?

I came across this problem because my cols exceeded the row grid length (> 12)

A solution using 100% Bootstrap 4:

Since the rows in Bootstrap are already display: flex

You just need to add flex-fill to the Col, and h-100 to the container and any children.

Pen here: https://codepen.io/joshkopecek/pen/Exjdgjo

<div class="container-fluid h-100">
  <div class="row justify-content-center h-100">

    <div class="col-4 hidden-md-down flex-fill" id="yellow">
      XXXX
    </div>

    <div id="blue" class="col-10 col-sm-10 col-md-10 col-lg-8 col-xl-8 h-100">
      Form Goes Here
    </div>

    <div id="green" class="col-10 col-sm-10 col-md-10 col-lg-8 col-xl-8 h-100">
      Another form
    </div>
  </div>
</div>

I want to declare an empty array in java and then I want do update it but the code is not working

You are creating an array of zero length (no slots to put anything in)

 int array[]={/*nothing in here = array with no elements*/};

and then trying to assign values to array elements (which you don't have, because there are no slots)

array[i] = number; //array[i] = element i in the array of length 0

You need to define a larger array to fit your needs

 int array[] = new int[4]; //Create an array with 4 elements [0],[1],[2] and [3] each containing an int value

Including external jar-files in a new jar-file build with Ant

From your ant buildfile, I assume that what you want is to create a single JAR archive that will contain not only your application classes, but also the contents of other JARs required by your application.

However your build-jar file is just putting required JARs inside your own JAR; this will not work as explained here (see note).

Try to modify this:

<jar destfile="${jar.file}" 
    basedir="${build.dir}" 
    manifest="${manifest.file}">
    <fileset dir="${classes.dir}" includes="**/*.class" />
    <fileset dir="${lib.dir}" includes="**/*.jar" />
</jar>

to this:

<jar destfile="${jar.file}" 
    basedir="${build.dir}" 
    manifest="${manifest.file}">
    <fileset dir="${classes.dir}" includes="**/*.class" />
    <zipgroupfileset dir="${lib.dir}" includes="**/*.jar" />
</jar>

More flexible and powerful solutions are the JarJar or One-Jar projects. Have a look into those if the above does not satisfy your requirements.

How to make a JFrame Modal in Swing java

just replace JFrame to JDialog in class

public class MyDialog extends JFrame // delete JFrame and write JDialog

and then write setModal(true); in constructor

After that you will be able to construct your Form in netbeans and the form becomes modal

How to replace unicode characters in string with something else python?

Encode string as unicode.

>>> special = u"\u2022"
>>> abc = u'ABC•def'
>>> abc.replace(special,'X')
u'ABCXdef'

How to hide a navigation bar from first ViewController in Swift?

In IOS 8 do it like

navigationController?.hidesBarsOnTap = true

but only when it's part of a UINavigationController

make it false when you want it back

Query to select data between two dates with the format m/d/yyyy

select * from xxx where dates between '2012-10-10' and '2012-10-12'

I always use YYYY-MM-DD in my views and never had any issue. Plus, it is readable and non equivocal.
You should be aware that using BETWEEN might not return what you expect with a DATETIME field, since it would eliminate records dated '2012-10-12 08:00' for example.
I would rather use where dates >= '2012-10-10' and dates < '2012-10-13' (lower than next day)

Drawing an SVG file on a HTML5 canvas

Mozilla has a simple way for drawing SVG on canvas called "Drawing DOM objects into a canvas"

How can I force clients to refresh JavaScript files?

One solution is to append a query string with a timestamp in it to the URL when fetching the resource. This takes advantage of the fact that a browser will not cache resources fetched from URLs with query strings in them.

You probably don't want the browser not to cache these resources at all though; it's more likely that you want them cached, but you want the browser to fetch a new version of the file when it is made available.

The most common solution seems to be to embed a timestamp or revision number in the file name itself. This is a little more work, because your code needs to be modified to request the correct files, but it means that, e.g. version 7 of your snazzy_javascript_file.js (i.e. snazzy_javascript_file_7.js) is cached on the browser until you release version 8, and then your code changes to fetch snazzy_javascript_file_8.js instead.

How to check if another instance of my shell script is running

I create a temporary file during execution.

This is how I do it:

#!/bin/sh
# check if lock file exists
if [ -e /tmp/script.lock ]; then
  echo "script is already running"
else
# create a lock file
  touch /tmp/script.lock
  echo "run script..."
#remove lock file
 rm /tmp/script.lock
fi

CSS selector - element with a given child

Is it possible to select an element if it contains a specific child element?

Unfortunately not yet.

The CSS2 and CSS3 selector specifications do not allow for any sort of parent selection.


A Note About Specification Changes

This is a disclaimer about the accuracy of this post from this point onward. Parent selectors in CSS have been discussed for many years. As no consensus has been found, changes keep happening. I will attempt to keep this answer up-to-date, however be aware that there may be inaccuracies due to changes in the specifications.


An older "Selectors Level 4 Working Draft" described a feature which was the ability to specify the "subject" of a selector. This feature has been dropped and will not be available for CSS implementations.

The subject was going to be the element in the selector chain that would have styles applied to it.

Example HTML
<p><span>lorem</span> ipsum dolor sit amet</p>
<p>consecteture edipsing elit</p>

This selector would style the span element

p span {
    color: red;
}

This selector would style the p element

!p span {
    color: red;
}

A more recent "Selectors Level 4 Editor’s Draft" includes "The Relational Pseudo-class: :has()"

:has() would allow an author to select an element based on its contents. My understanding is it was chosen to provide compatibility with jQuery's custom :has() pseudo-selector*.

In any event, continuing the example from above, to select the p element that contains a span one could use:

p:has(span) {
    color: red;
}

* This makes me wonder if jQuery had implemented selector subjects whether subjects would have remained in the specification.

Ansible - Save registered variable to file

More readable way of achieving this (not a fan of single line ansible tasks)

- local_action: 
    module: copy 
    content: "{{ foo_result }}"
    dest: /path/to/destination/file

Determine if Python is running inside virtualenv

This is an old question, but too many examples above are over-complicated.

Keep It Simple: (in Jupyter Notebook or Python 3.7.1 terminal on Windows 10)


import sys
print(sys.executable)```

# example output: >> `C:\Anaconda3\envs\quantecon\python.exe`

OR 
```sys.base_prefix```

# Example output: >> 'C:\\Anaconda3\\envs\\quantecon'

How to set a value to a file input in HTML?

Not an answer to your question (which others have answered), but if you want to have some edit functionality of an uploaded file field, what you probably want to do is:

  • show the current value of this field by just printing the filename or URL, a clickable link to download it, or if it's an image: just show it, possibly as thumbnail
  • the <input> tag to upload a new file
  • a checkbox that, when checked, deletes the currently uploaded file. note that there's no way to upload an 'empty' file, so you need something like this to clear out the field's value

What is the Difference Between read() and recv() , and Between send() and write()?

On Linux I also notice that :

Interruption of system calls and library functions by signal handlers
If a signal handler is invoked while a system call or library function call is blocked, then either:

  • the call is automatically restarted after the signal handler returns; or

  • the call fails with the error EINTR.

... The details vary across UNIX systems; below, the details for Linux.

If a blocked call to one of the following interfaces is interrupted by a signal handler, then the call is automatically restarted after the signal handler returns if the SA_RESTART flag was used; otherwise the call fails with the error EINTR:

  • read(2), readv(2), write(2), writev(2), and ioctl(2) calls on "slow" devices.

.....

The following interfaces are never restarted after being interrupted by a signal handler, regardless of the use of SA_RESTART; they always fail with the error EINTR when interrupted by a signal handler:

  • "Input" socket interfaces, when a timeout (SO_RCVTIMEO) has been set on the socket using setsockopt(2): accept(2), recv(2), recvfrom(2), recvmmsg(2) (also with a non-NULL timeout argument), and recvmsg(2).

  • "Output" socket interfaces, when a timeout (SO_RCVTIMEO) has been set on the socket using setsockopt(2): connect(2), send(2), sendto(2), and sendmsg(2).

Check man 7 signal for more details.


A simple usage would be use signal to avoid recvfrom blocking indefinitely.

An example from APUE:

#include "apue.h"
#include <netdb.h>
#include <errno.h>
#include <sys/socket.h>

#define BUFLEN      128
#define TIMEOUT     20

void
sigalrm(int signo)
{
}

void
print_uptime(int sockfd, struct addrinfo *aip)
{
    int     n;
    char    buf[BUFLEN];

    buf[0] = 0;
    if (sendto(sockfd, buf, 1, 0, aip->ai_addr, aip->ai_addrlen) < 0)
        err_sys("sendto error");
    alarm(TIMEOUT);
    //here
    if ((n = recvfrom(sockfd, buf, BUFLEN, 0, NULL, NULL)) < 0) {
        if (errno != EINTR)
            alarm(0);
        err_sys("recv error");
    }
    alarm(0);
    write(STDOUT_FILENO, buf, n);
}

int
main(int argc, char *argv[])
{
    struct addrinfo     *ailist, *aip;
    struct addrinfo     hint;
    int                 sockfd, err;
    struct sigaction    sa;

    if (argc != 2)
        err_quit("usage: ruptime hostname");
    sa.sa_handler = sigalrm;
    sa.sa_flags = 0;
    sigemptyset(&sa.sa_mask);
    if (sigaction(SIGALRM, &sa, NULL) < 0)
        err_sys("sigaction error");
    memset(&hint, 0, sizeof(hint));
    hint.ai_socktype = SOCK_DGRAM;
    hint.ai_canonname = NULL;
    hint.ai_addr = NULL;
    hint.ai_next = NULL;
    if ((err = getaddrinfo(argv[1], "ruptime", &hint, &ailist)) != 0)
        err_quit("getaddrinfo error: %s", gai_strerror(err));

    for (aip = ailist; aip != NULL; aip = aip->ai_next) {
        if ((sockfd = socket(aip->ai_family, SOCK_DGRAM, 0)) < 0) {
            err = errno;
        } else {
            print_uptime(sockfd, aip);
            exit(0);
        }
    }

    fprintf(stderr, "can't contact %s: %s\n", argv[1], strerror(err));
    exit(1);
}

Change icon-bar (?) color in bootstrap

The reason your CSS isn't working is because of specificity. The Bootstrap selector has a higher specificity than yours, so your style is completely ignored.

Bootstrap styles this with the selector: .navbar-default .navbar-toggle .icon-bar. This selector has a B specificity value of 3, whereas yours only has a B specificity value of 1.

Therefore, to override this, simply use the same selector in your CSS (assuming your CSS is included after Bootstrap's):

.navbar-default .navbar-toggle .icon-bar {
    background-color: black;
}

How to unzip files programmatically in Android?

Password Protected Zip File

if you want to compress files with password you can take a look at this library that can zip files with password easily:

Zip:

ZipArchive zipArchive = new ZipArchive();
zipArchive.zip(targetPath,destinationPath,password);

Unzip:

ZipArchive zipArchive = new ZipArchive();
zipArchive.unzip(targetPath,destinationPath,password);

Rar:

RarArchive rarArchive = new RarArchive();
rarArchive.extractArchive(file archive, file destination);

The documentation of this library is good enough, I just added a few examples from there. It's totally free and wrote specially for android.

How do I get into a non-password protected Java keystore or change the password?

Getting into a non-password protected Java keystore and changing the password can be done with a help of Java programming language itself.

That article contains the code for that:

thetechawesomeness.ideasmatter.info

Simple VBA selection: Selecting 5 cells to the right of the active cell

This copies the 5 cells to the right of the activecell. If you have a range selected, the active cell is the top left cell in the range.

Sub Copy5CellsToRight()
    ActiveCell.Offset(, 1).Resize(1, 5).Copy
End Sub

If you want to include the activecell in the range that gets copied, you don't need the offset:

Sub ExtendAndCopy5CellsToRight()
    ActiveCell.Resize(1, 6).Copy
End Sub

Note that you don't need to select before copying.

How can I get the name of an html page in Javascript?

Current page: It's possible to do even shorter. This single line sound more elegant to find the current page's file name:

var fileName = location.href.split("/").slice(-1); 

or...

var fileName = location.pathname.split("/").slice(-1)

This is cool to customize nav box's link, so the link toward the current is enlighten by a CSS class.

JS:

$('.menu a').each(function() {
    if ($(this).attr('href') == location.href.split("/").slice(-1)){ $(this).addClass('curent_page'); }
});

CSS:

a.current_page { font-size: 2em; color: red; }

How do I add a margin between bootstrap columns without wrapping

I was facing the same issue; and the following worked well for me. Hope this helps someone landing here:

<div class="row">
    <div class="col-md-6">
        <div class="col-md-12">
            Set room heater temperature
        </div>
    </div>
    <div class="col-md-6">
        <div class="col-md-12">
            Set room heater temperature
        </div>
    </div>
</div>

This will automatically render some space between the 2 divs. enter image description here

How to uninstall Python 2.7 on a Mac OS X 10.6.4?

Trying to uninstall Python with

brew uninstall python

will not remove the natively installed Python but rather the version installed with brew.

Regarding Java switch statements - using return and omitting breaks in each case

Best case for human logic to computer generated bytecode would be to utilize code like the following:

private double translateSlider(int sliderVal) {
  float retval = 1.0;

  switch (sliderVal) {
    case 1: retval = 0.9; break;
    case 2: retval = 0.8; break;
    case 3: retval = 0.7; break;
    case 4: retval = 0.6; break;
    case 0:
    default: break;
  }
  return retval;
}

Thus eliminating multiple exits from the method and utilizing the language logically. (ie while sliderVal is an integer range of 1-4 change float value else if sliderVal is 0 and all other values, retval stays the same float value of 1.0)

However something like this with each integer value of sliderVal being (n-(n/10)) one really could just do a lambda and get a faster results:

private double translateSlider = (int sliderVal) -> (1.0-(siderVal/10));

Edit: A modulus of 4 may be in order to keep logic (ie (n-(n/10))%4))

How can I debug git/git-shell related problems?

For even more verbose output use following:

GIT_CURL_VERBOSE=1 GIT_TRACE=1 git pull origin master

Getting activity from context in android

If you like to call an activity method from within a custom layout class(non-Activity Class).You should create a delegate using interface.

It is untested and i coded it right . but i am conveying a way to achieve what you want.

First of all create and Interface

interface TaskCompleteListener<T> {
   public void onProfileClicked(T result);
}



public class ProfileView extends LinearLayout
{
    private TaskCompleteListener<String> callback;
    TextView profileTitleTextView;
    ImageView profileScreenImageButton;
    boolean isEmpty;
    ProfileData data;
    String name;

    public ProfileView(Context context, AttributeSet attrs, String name, final ProfileData profileData)
    {
        super(context, attrs);
        ......
        ......
    }
    public setCallBack( TaskCompleteListener<String> cb) 
    {
      this.callback = cb;
    }
    //Heres where things get complicated
    public void onClick(View v)
    {
        callback.onProfileClicked("Pass your result or any type");
    }
}

And implement this to any Activity.

and call it like

ProfileView pv = new ProfileView(actvitiyContext, null, temp, tempPd);
pv.setCallBack(new TaskCompleteListener
               {
                   public void onProfileClicked(String resultStringFromProfileView){}
               });

Get the last item in an array

Performance

Today 2020.05.16 I perform tests of chosen solutions on Chrome v81.0, Safari v13.1 and Firefox v76.0 on MacOs High Sierra v10.13.6

Conclusions

  • arr[arr.length-1] (D) is recommended as fastest cross-browser solution
  • mutable solution arr.pop() (A) and immutable _.last(arr) (L) are fast
  • solutions I, J are slow for long strings
  • solutions H, K (jQuery) are slowest on all browsers

enter image description here

Details

I test two cases for solutions:

  • mutable: A, B, C,

  • immutable: D, E, F, G, H, I, J (my),

  • immutable from external libraries: K, L, M,

for two cases

  • short string - 10 characters - you can run test HERE
  • long string - 1M characters - you can run test HERE

_x000D_
_x000D_
function A(arr) {
  return arr.pop();
}

function B(arr) {  
  return arr.splice(-1,1);
}

function C(arr) {  
  return arr.reverse()[0]
}

function D(arr) {
  return arr[arr.length - 1];
}

function E(arr) {
  return arr.slice(-1)[0] ;
}

function F(arr) {
  let [last] = arr.slice(-1);
  return last;
}

function G(arr) {
  return arr.slice(-1).pop();
}

function H(arr) {
  return [...arr].pop();
}

function I(arr) {  
  return arr.reduceRight(a => a);
}

function J(arr) {  
  return arr.find((e,i,a)=> a.length==i+1);
}

function K(arr) {  
  return $(arr).get(-1);
}

function L(arr) {  
  return _.last(arr);
}

function M(arr) {  
  return _.nth(arr, -1);
}






// ----------
// TEST
// ----------

let loc_array=["domain","a","b","c","d","e","f","g","h","file"];

log = (f)=> console.log(`${f.name}: ${f([...loc_array])}`);

[A,B,C,D,E,F,G,H,I,J,K,L,M].forEach(f=> log(f));
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.min.js" integrity="sha256-VeNaFBVDhoX3H+gJ37DpT/nTuZTdjYro9yBruHjVmoQ=" crossorigin="anonymous"></script>
_x000D_
_x000D_
_x000D_

Example results for Chrome for short string

enter image description here

ASP.NET Temporary files cleanup

Just an update on more current OS's (Vista, Win7, etc.) - the temp file path has changed may be different based on several variables. The items below are not definitive, however, they are a few I have encountered:

"temp" environment variable setting - then it would be:

%temp%\Temporary ASP.NET Files

Permissions and what application/process (VS, IIS, IIS Express) is running the .Net compiler. Accessing the C:\WINDOWS\Microsoft.NET\Framework folders requires elevated permissions and if you are not developing under an account with sufficient permissions then this folder might be used:

c:\Users\[youruserid]\AppData\Local\Temp\Temporary ASP.NET Files

There are also cases where the temp folder can be set via config for a machine or site specific using this:

<compilation tempDirectory="d:\MyTempPlace" />

I even have a funky setup at work where we don't run Admin by default, plus the IT guys have login scripts that set %temp% and I get temp files in 3 different locations depending on what is compiling things! And I'm still not certain about how these paths get picked....sigh.

Still, dthrasher is correct, you can just delete these and VS and IIS will just recompile them as needed.

Calculate correlation for more than two variables?

If you would like to combine the matrix with some visualisations I can recommend (I am using the built in iris dataset):

library(psych)
pairs.panels(iris[1:4])  # select columns 1-4

enter image description here

The Performance Analytics basically does the same but includes significance indicators by default.

library(PerformanceAnalytics)
chart.Correlation(iris[1:4])

Correlation Chart

Or this nice and simple visualisation:

library(corrplot)
x <- cor(iris[1:4])
corrplot(x, type="upper", order="hclust")

corrplot

Simulate user input in bash script

You should find the 'expect' command will do what you need it to do. Its widely available. See here for an example : http://www.thegeekstuff.com/2010/10/expect-examples/

(very rough example)

#!/usr/bin/expect
set pass "mysecret"

spawn /usr/bin/passwd

expect "password: "
send "$pass"
expect "password: "
send "$pass"

MySQL wait_timeout Variable - GLOBAL vs SESSION

Your session status are set once you start a session, and by default, take the current GLOBAL value.

If you disconnected after you did SET @@GLOBAL.wait_timeout=300, then subsequently reconnected, you'd see

SHOW SESSION VARIABLES LIKE "%wait%";

Result: 300

Similarly, at any time, if you did

mysql> SET session wait_timeout=300;

You'd get

mysql> SHOW SESSION VARIABLES LIKE 'wait_timeout';

+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wait_timeout  | 300   |
+---------------+-------+

Where is Android Studio layout preview?

The following worked for me:

-> file

-> settings

-> plugins

-> disable the android support plugin

-> you will be prompted to restart

-> once restarted re-enable the plugin and other dependency plugins that might have been disabled in the process

-> you will be prompted to restart once again. Hopefully when android studio restarts the second time the preview should render.

Java 'file.delete()' Is not Deleting Specified File

Since the directory is not empty, file.delete() returns false, always.

I used

file.deleteRecursively()

which is available in Kotlin and would delete the completely directly and return the boolean response just as file.delete() does.

python pip - install from local dir

You were looking for help on installations with pip. You can find it with the following command:

pip install --help

Running pip install -e /path/to/package installs the package in a way, that you can edit the package, and when a new import call looks for it, it will import the edited package code. This can be very useful for package development.

What determines the monitor my app runs on?

I've noticed that if I put a shortcut on my desktop on one screen the launched application may appear on that screen (if that app doesn't reposition itself).

This also applies to running things from Windows Explorer - if Explorer is on one screen the launched application will pick that monitor to use.

Again - I think this is when the launching application specifies the default (windows managed) position. Most applications seem to override this default behavior in some way.

A simple window created like so will do this:

hWnd = CreateWindow(windowClass, windowTitle, WS_VISIBLE | WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, SW_SHOW, CW_USEDEFAULT, 0, NULL, NULL, hInst, NULL);

Java: Clear the console

If you want a more system independent way of doing this, you can use the JLine library and ConsoleReader.clearScreen(). Prudent checking of whether JLine and ANSI is supported in the current environment is probably worth doing too.

Something like the following code worked for me:

import jline.console.ConsoleReader;

public class JLineTest
{
    public static void main(String... args)
    throws Exception
    {
        ConsoleReader r = new ConsoleReader();

        while (true)
        {
            r.println("Good morning");
            r.flush();

            String input = r.readLine("prompt>");

            if ("clear".equals(input))
                r.clearScreen();
            else if ("exit".equals(input))
                return;
            else
                System.out.println("You typed '" + input + "'.");

        }
    }
}

When running this, if you type 'clear' at the prompt it will clear the screen. Make sure you run it from a proper terminal/console and not in Eclipse.

How to implement a SQL like 'LIKE' operator in java?

i dont know exactly about the greedy issue, but try this if it works for you:

public boolean like(final String str, String expr)
  {
    final String[] parts = expr.split("%");
    final boolean traillingOp = expr.endsWith("%");
    expr = "";
    for (int i = 0, l = parts.length; i < l; ++i)
    {
      final String[] p = parts[i].split("\\\\\\?");
      if (p.length > 1)
      {
        for (int y = 0, l2 = p.length; y < l2; ++y)
        {
          expr += p[y];
          if (i + 1 < l2) expr += ".";
        }
      }
      else
      {
        expr += parts[i];
      }
      if (i + 1 < l) expr += "%";
    }
    if (traillingOp) expr += "%";
    expr = expr.replace("?", ".");
    expr = expr.replace("%", ".*");
    return str.matches(expr);
}

Calling another different view from the controller using ASP.NET MVC 4

To return a different view, you can specify the name of the view you want to return and model as follows:

return View("ViewName", yourModel);

if the view is in different folder under Views folder then use below absolute path:

return View("~/Views/FolderName/ViewName.aspx");

Best way to convert IList or IEnumerable to Array

Which version of .NET are you using? If it's .NET 3.5, I'd just call ToArray() and be done with it.

If you only have a non-generic IEnumerable, do something like this:

IEnumerable query = ...;
MyEntityType[] array = query.Cast<MyEntityType>().ToArray();

If you don't know the type within that method but the method's callers do know it, make the method generic and try this:

public static void T[] PerformQuery<T>()
{
    IEnumerable query = ...;
    T[] array = query.Cast<T>().ToArray();
    return array;
}

Android WebView progress bar

This is how I did it with Kotlin to show progress with percentage.

My fragment layout.

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
         xmlns:tools="http://schemas.android.com/tools"
         android:layout_width="match_parent"
         android:layout_height="match_parent">

<WebView
    android:id="@+id/webView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>

<ProgressBar
    android:layout_marginLeft="32dp"
    android:layout_marginRight="32dp"
    style="?android:attr/progressBarStyleHorizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:id="@+id/progressBar"/>
</FrameLayout>

My kotlin fragment in onViewCreated

    progressBar.max = 100;
    webView.webChromeClient = object : WebChromeClient() {
        override fun onProgressChanged(view: WebView?, newProgress: Int) {
            super.onProgressChanged(view, newProgress)
            progressBar.progress = newProgress;
        }
    }

    webView!!.webViewClient = object : WebViewClient() {

        override fun onPageStarted(view: WebView?, url: String?, favicon: Bitmap?) {
            progressBar.visibility = View.VISIBLE
            progressBar.progress = 0;
            super.onPageStarted(view, url, favicon)
        }

        override fun shouldOverrideUrlLoading(view: WebView?, url: String?): Boolean {
            view?.loadUrl(url)
            return true
        }

        override fun shouldOverrideUrlLoading(
            view: WebView?,
            request: WebResourceRequest?): Boolean {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                view?.loadUrl(request?.url.toString())
            }
            return true
        }

        override fun onPageFinished(view: WebView?, url: String?) {
            super.onPageFinished(view, url)
            progressBar.visibility = View.GONE
        }
    }

    webView.loadUrl(url)

asp.net validation to make sure textbox has integer values

You can use java script for this:-

<asp:TextBox ID="textbox1" runat="server" Width="150px" MaxLength="8" onkeypress="if(event.keyCode<48 || event.keyCode>57)event.returnValue=false;"></asp:TextBox>

How to I say Is Not Null in VBA

you can do like follows. Remember, IsNull is a function which returns TRUE if the parameter passed to it is null, and false otherwise.

Not IsNull(Fields!W_O_Count.Value)

Batch file: Find if substring is in string (not in a file)

You can pipe the source string to findstr and check the value of ERRORLEVEL to see if the pattern string was found. A value of zero indicates success and the pattern was found. Here is an example:

::
: Y.CMD - Test if pattern in string
: P1 - the pattern
: P2 - the string to check
::
@echo off

echo.%2 | findstr /C:"%1" 1>nul

if errorlevel 1 (
  echo. got one - pattern not found
) ELSE (
  echo. got zero - found pattern
)

When this is run in CMD.EXE, we get:

C:\DemoDev>y pqrs "abc def pqr 123"
 got one - pattern not found

C:\DemoDev>y pqr "abc def pqr 123" 
 got zero - found pattern

React Native Change Default iOS Simulator Device

Get device list with this command

xcrun simctl list devices

Console

== Devices ==
-- iOS 13.5 --
    iPhone 6s (9981E5A5-48A8-4B48-B203-1C6E73243E83) (Shutdown) 
    iPhone 8 (FC540A6C-F374-4113-9E71-1291790C8C4C) (Shutting Down) 
    iPhone 8 Plus (CAC37462-D873-4EBB-9D71-7C6D0C915C12) (Shutdown) 
    iPhone 11 (347EFE28-9B41-4C1A-A4C3-D99B49300D8B) (Shutting Down) 
    iPhone 11 Pro (5AE964DC-201C-48C9-BFB5-4506E3A0018F) (Shutdown) 
    iPhone 11 Pro Max (48EE985A-39A6-426C-88A4-AA1E4AFA0133) (Shutdown) 
    iPhone SE (2nd generation) (48B78183-AFD7-4832-A80E-AF70844222BA) (Shutdown) 
    iPad Pro (9.7-inch) (2DEF27C4-6A18-4477-AC7F-FB31CCCB3960) (Shutdown) 
    iPad (7th generation) (36A4AF6B-1232-4BCB-B74F-226E025225E4) (Shutdown) 
    iPad Pro (11-inch) (2nd generation) (79391BD7-0E55-44C8-B1F9-AF92A1D57274) (Shutdown) 
    iPad Pro (12.9-inch) (4th generation) (ED90A31F-6B20-4A6B-9EE9-CF22C01E8793) (Shutdown) 
    iPad Air (3rd generation) (41AD1CF7-CB0D-4F18-AB1E-6F8B6261AD33) (Shutdown) 
-- tvOS 13.4 --
    Apple TV 4K (51925935-97F4-4242-902F-041F34A66B82) (Shutdown) 
-- watchOS 6.2 --
    Apple Watch Series 5 - 40mm (7C50F2E9-A52B-4E0D-8B81-A811FE995502) (Shutdown) 
    Apple Watch Series 5 - 44mm (F7D8C256-DC9F-4FDC-8E65-63275C222B87) (Shutdown) 

Select Simulator string without ID here is an example.

iPad Pro (12.9-inch) (4th generation)

Final command

iPhone

• iPhone 6s

react-native run-ios --simulator="iPhone 6s"

• iPhone 8

react-native run-ios --simulator="iPhone 8"

• iPhone 8 Plus

react-native run-ios --simulator="iPhone 8 Plus"

• iPhone 11

react-native run-ios --simulator="iPhone 11"

• iPhone 11 Pro

react-native run-ios --simulator="iPhone 11 Pro"

• iPhone 11 Pro Max

react-native run-ios --simulator="iPhone 11 Pro Max"

• iPhone SE (2nd generation)

react-native run-ios --simulator="iPhone SE (2nd generation)"

iPad

• iPad Pro (9.7-inch)

react-native run-ios --simulator="iPad Pro (9.7-inch)"

• iPad (7th generation)

react-native run-ios --simulator="iPad (7th generation)"

• iPad Pro (11-inch) (2nd generation)

react-native run-ios --simulator="iPad Pro (11-inch) (2nd generation)"

• iPad Pro (12.9-inch) 4th generation

react-native run-ios --simulator="iPad Pro (12.9-inch) (4th generation)"

• iPad Air (3rd generation)

react-native run-ios --simulator="iPad Air (3rd generation)"

How to scp in Python?

You might be interested in trying Pexpect (source code). This would allow you to deal with interactive prompts for your password.

Here's a snip of example usage (for ftp) from the main website:

# This connects to the openbsd ftp site and
# downloads the recursive directory listing.
import pexpect
child = pexpect.spawn ('ftp ftp.openbsd.org')
child.expect ('Name .*: ')
child.sendline ('anonymous')
child.expect ('Password:')
child.sendline ('[email protected]')
child.expect ('ftp> ')
child.sendline ('cd pub')
child.expect('ftp> ')
child.sendline ('get ls-lR.gz')
child.expect('ftp> ')
child.sendline ('bye')

QLabel: set color of text and background

You can use QPalette, however you must set setAutoFillBackground(true); to enable background color

QPalette sample_palette;
sample_palette.setColor(QPalette::Window, Qt::white);
sample_palette.setColor(QPalette::WindowText, Qt::blue);

sample_label->setAutoFillBackground(true);
sample_label->setPalette(sample_palette);
sample_label->setText("What ever text");

It works fine on Windows and Ubuntu, I haven't played with any other OS.

Note: Please see QPalette, color role section for more details

How to convert a Java 8 Stream to an Array?

You can convert a java 8 stream to an array using this simple code block:

 String[] myNewArray3 = myNewStream.toArray(String[]::new);

But let's explain things more, first, let's Create a list of string filled with three values:

String[] stringList = {"Bachiri","Taoufiq","Abderrahman"};

Create a stream from the given Array :

Stream<String> stringStream = Arrays.stream(stringList);

we can now perform some operations on this stream Ex:

Stream<String> myNewStream = stringStream.map(s -> s.toUpperCase());

and finally convert it to a java 8 Array using these methods:

1-Classic method (Functional interface)

IntFunction<String[]> intFunction = new IntFunction<String[]>() {
    @Override
    public String[] apply(int value) {
        return new String[value];
    }
};


String[] myNewArray = myNewStream.toArray(intFunction);

2 -Lambda expression

 String[] myNewArray2 = myNewStream.toArray(value -> new String[value]);

3- Method reference

String[] myNewArray3 = myNewStream.toArray(String[]::new);

Method reference Explanation:

It's another way of writing a lambda expression that it's strictly equivalent to the other.

Group a list of objects by an attribute

Function<Student, List<Object>> compositKey = std ->
                Arrays.asList(std.stud_location());
        studentList.stream().collect(Collectors.groupingBy(compositKey, Collectors.toList()));

If you want to add multiple objects for group by you can simply add the object in compositKey method separating by a comma:

Function<Student, List<Object>> compositKey = std ->
                Arrays.asList(std.stud_location(),std.stud_name());
        studentList.stream().collect(Collectors.groupingBy(compositKey, Collectors.toList()));

error: function returns address of local variable

This line:

char b = "blah";

Is no good - your lvalue needs to be a pointer.

Your code is also in danger of a stack overflow, since your recursion check isn't bounding the decreasing value of x.

Anyway, the actual error message you are getting is because char a is an automatic variable; the moment you return it will cease to exist. You need something other than an automatic variable.

Div Height in Percentage

You need to give the body and the html a height too. Otherwise, the body will only be as high as its contents (the single div), and 50% of that will be half the height of this div.

Updated fiddle: http://jsfiddle.net/j8bsS/5/

What are naming conventions for MongoDB?

I think it's all personal preference. My preferences come from using NHibernate, in .NET, with SQL Server, so they probably differ from what others use.

  • Databases: The application that's being used.. ex: Stackoverflow
  • Collections: Singular in name, what it's going to be a collection of, ex: Question
  • Document fields, ex: MemberFirstName

Honestly, it doesn't matter too much, as long as it's consistent for the project. Just get to work and don't sweat the details :P

Scraping: SSL: CERTIFICATE_VERIFY_FAILED error for http://en.wikipedia.org

I am using Debian 10 buster and try download a file with youtube-dl and get this error: sudo youtube-dl -k https://youtu.be/uscis0CnDjk

[youtube] uscis0CnDjk: Downloading webpage ERROR: Unable to download webpage: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1056)> (caused by URLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1056)')))

Certificates with python2 and python3.8 are installed correctly, but i persistent receive the same error. finally (which is not the best solution, but works for me was to eliminate the certificate check as it is given as an option in youtube-dl) whith this command sudo youtube-dl -k --no-check-certificate https://youtu.be/uscis0CnDjk

Adding click event handler to iframe

You can use closures to pass parameters:

iframe.document.addEventListener('click', function(event) {clic(this.id);}, false);

However, I recommend that you use a better approach to access your frame (I can only assume that you are using the DOM0 way of accessing frame windows by their name - something that is only kept around for backwards compatibility):

document.getElementById("myFrame").contentDocument.addEventListener(...);

Using Cookie in Asp.Net Mvc 4

Try using Response.SetCookie(), because Response.Cookies.Add() can cause multiple cookies to be added, whereas SetCookie will update an existing cookie.

How to make a JSON call to a url?

DickFeynman's answer is a workable solution for any circumstance in which JQuery is not a good fit, or isn't otherwise necessary. As ComFreek notes, this requires setting the CORS headers on the server-side. If it's your service, and you have a handle on the bigger question of security, then that's entirely feasible.

Here's a listing of a Flask service, setting the CORS headers, grabbing data from a database, responding with JSON, and working happily with DickFeynman's approach on the client-side:

#!/usr/bin/env python 
from __future__ import unicode_literals
from flask      import Flask, Response, jsonify, redirect, request, url_for
from your_model import *
import os
try:
    import simplejson as json;
except ImportError:
    import json
try:
    from flask.ext.cors import *
except:
    from flask_cors import *

app = Flask(__name__)

@app.before_request
def before_request():
try:
    # Provided by an object in your_model
    app.session = SessionManager.connect()
except:
    print "Database connection failed."

@app.teardown_request
def shutdown_session(exception=None):
    app.session.close()

# A route with a CORS header, to enable your javascript client to access 
# JSON created from a database query.
@app.route('/whatever-data/', methods=['GET', 'OPTIONS'])
@cross_origin(headers=['Content-Type'])
def json_data():
    whatever_list = []
    results_json  = None
    try:
        # Use SQL Alchemy to select all Whatevers, WHERE size > 0.
        whatevers = app.session.query(Whatever).filter(Whatever.size > 0).all()
        if whatevers and len(whatevers) > 0:
            for whatever in whatevers:
                # Each whatever is able to return a serialized version of itself. 
                # Refer to your_model.
                whatever_list.append(whatever.serialize())
             # Convert a list to JSON. 
             results_json = json.dumps(whatever_list)
    except SQLAlchemyError as e:
        print 'Error {0}'.format(e)
        exit(0)

    if len(whatevers) < 1 or not results_json:
        exit(0)
    else:
        # Because we used json.dumps(), rather than jsonify(), 
        # we need to create a Flask Response object, here.
        return Response(response=str(results_json), mimetype='application/json')

if __name__ == '__main__':
    #@NOTE Not suitable for production. As configured, 
    #      your Flask service is in debug mode and publicly accessible.  
    app.run(debug=True, host='0.0.0.0', port=5001) # http://localhost:5001/

your_model contains the serialization method for your whatever, as well as the database connection manager (which could stand a little refactoring, but suffices to centralize the creation of database sessions, in bigger systems or Model/View/Control architectures). This happens to use postgreSQL, but could just as easily use any server side data store:

#!/usr/bin/env python 
# Filename: your_model.py
import time
import psycopg2
import psycopg2.pool
import psycopg2.extras
from   psycopg2.extensions        import adapt, register_adapter, AsIs
from   sqlalchemy                 import update
from   sqlalchemy.orm             import *
from   sqlalchemy.exc             import *
from   sqlalchemy.dialects        import postgresql
from   sqlalchemy                 import Table, Column, Integer, ForeignKey
from   sqlalchemy.ext.declarative import declarative_base

class SessionManager(object):
    @staticmethod
    def connect():
        engine = create_engine('postgresql://id:passwd@localhost/mydatabase', 
                                echo = True)
        Session = sessionmaker(bind = engine, 
                               autoflush = True, 
                               expire_on_commit = False, 
                               autocommit = False)
    session = Session()
    return session

  @staticmethod
  def declareBase():
      engine = create_engine('postgresql://id:passwd@localhost/mydatabase', echo=True)
      whatever_metadata = MetaData(engine, schema ='public')
      Base = declarative_base(metadata=whatever_metadata)
      return Base

Base = SessionManager.declareBase()

class Whatever(Base):
    """Create, supply information about, and manage the state of one or more whatever.
    """
    __tablename__         = 'whatever'
    id                    = Column(Integer, primary_key=True)
    whatever_digest       = Column(VARCHAR, unique=True)
    best_name             = Column(VARCHAR, nullable = True)
    whatever_timestamp    = Column(BigInteger, default = time.time())
    whatever_raw          = Column(Numeric(precision = 1000, scale = 0), default = 0.0)
    whatever_label        = Column(postgresql.VARCHAR, nullable = True)
    size                  = Column(BigInteger, default = 0)

    def __init__(self, 
                 whatever_digest = '', 
                 best_name = '', 
                 whatever_timestamp = 0, 
                 whatever_raw = 0, 
                 whatever_label = '', 
                 size = 0):
        self.whatever_digest         = whatever_digest
        self.best_name               = best_name
        self.whatever_timestamp      = whatever_timestamp
        self.whatever_raw            = whatever_raw
        self.whatever_label          = whatever_label

    # Serialize one way or another, just handle appropriately in the client.  
    def serialize(self):
        return {
            'best_name'     :self.best_name,
            'whatever_label':self.whatever_label,
            'size'          :self.size,
        }

In retrospect, I might have serialized the whatever objects as lists, rather than a Python dict, which might have simplified their processing in the Flask service, and I might have separated concerns better in the Flask implementation (The database call probably shouldn't be built-in the the route handler), but you can improve on this, once you have a working solution in your own development environment.

Also, I'm not suggesting people avoid JQuery. But, if JQuery's not in the picture, for one reason or another, this approach seems like a reasonable alternative.

It works, in any case.

Here's my implementation of DickFeynman's approach, in the the client:

<script type="text/javascript">
    var addr = "dev.yourserver.yourorg.tld"
    var port = "5001"

    function Get(whateverUrl){
        var Httpreq = new XMLHttpRequest(); // a new request
        Httpreq.open("GET",whateverUrl,false);
        Httpreq.send(null);
        return Httpreq.responseText;          
    }

    var whatever_list_obj = JSON.parse(Get("http://" + addr + ":" + port + "/whatever-data/"));
    whatever_qty = whatever_list_obj.length;
    for (var i = 0; i < whatever_qty; i++) {
        console.log(whatever_list_obj[i].best_name);
    }
</script>

I'm not going to list my console output, but I'm looking at a long list of whatever.best_name strings.

More to the point: The whatever_list_obj is available for use in my javascript namespace, for whatever I care to do with it, ...which might include generating graphics with D3.js, mapping with OpenLayers or CesiumJS, or calculating some intermediate values which have no particular need to live in my DOM.

How to change the URL from "localhost" to something else, on a local system using wampserver?

Copy the hosts file and add 127.0.0.1 and name which you want to show or run at the browser link. For example:

127.0.0.1   abc

Then run abc/ as a local host in the browser.

1

javascript: Disable Text Select

One might also use, works ok in all browsers, require javascript:

onselectstart = (e) => {e.preventDefault()}

Example:

_x000D_
_x000D_
onselectstart = (e) => {_x000D_
  e.preventDefault()_x000D_
  console.log("nope!")_x000D_
  }
_x000D_
Select me!
_x000D_
_x000D_
_x000D_


One other js alternative, by testing CSS supports, and disable userSelect, or MozUserSelect for Firefox.

_x000D_
_x000D_
let FF_x000D_
if (CSS.supports("( -moz-user-select: none )")){FF = 1} else {FF = 0}_x000D_
(FF===1) ? document.body.style.MozUserSelect="none" : document.body.style.userSelect="none"
_x000D_
Select me!
_x000D_
_x000D_
_x000D_


Pure css, same logic. Warning you will have to extend those rules to every browser, this can be verbose.

_x000D_
_x000D_
@supports (user-select:none) {_x000D_
  div {_x000D_
    user-select:none_x000D_
  }_x000D_
}_x000D_
_x000D_
@supports (-moz-user-select:none) {_x000D_
  div {_x000D_
    -moz-user-select:none_x000D_
  }_x000D_
}
_x000D_
<div>Select me!</div>
_x000D_
_x000D_
_x000D_

Setting selected option in laravel form

Setting selected option is very simple in laravel form :

{{ Form::select('number', [0, 1, 2], 2) }}

Output will be :

<select name="number">
  <option value="0">0</option>
  <option value="1">1</option>
  <option value="2" selected="selected">2</option>
</select>

Printing chars and their ASCII-code in C

This prints out all ASCII values:

int main()
{
    int i;
    i=0;
    do
    {
        printf("%d %c \n",i,i);
        i++;
    }
    while(i<=255);
    return 0;
}

and this prints out the ASCII value for a given character:

int main()
{
    int e;
    char ch;
    clrscr();
    printf("\n Enter a character : ");
    scanf("%c",&ch);
    e=ch;
    printf("\n The ASCII value of the character is : %d",e);
    getch();
    return 0;
}

How to hide a button programmatically?

Please used below

View.GONE and View.VISIBLE

Get current domain

Everybody is using the parse_url function, but sometimes user may pass the argumet in different format.

So as to fix that, I have created the function. Check this out:

function fixDomainName($url='')
{
    $strToLower = strtolower(trim($url));
    $httpPregReplace = preg_replace('/^http:\/\//i', '', $strToLower);
    $httpsPregReplace = preg_replace('/^https:\/\//i', '', $httpPregReplace);
    $wwwPregReplace = preg_replace('/^www\./i', '', $httpsPregReplace);
    $explodeToArray = explode('/', $wwwPregReplace);
    $finalDomainName = trim($explodeToArray[0]);
    return $finalDomainName;
}

Just pass the URL and get the domain.

For example,

echo fixDomainName('https://stackoverflow.com');

will return the result will be

stackoverflow.com

And in some situation:

echo fixDomainName('stackoverflow.com/questions/id/slug');

And it will also return stackoverflow.com.

TypeScript and field initializers

I suggest an approach that does not require Typescript 2.1:

class Person {
    public name: string;
    public address?: string;
    public age: number;

    public constructor(init:Person) {
        Object.assign(this, init);
    }

    public someFunc() {
        // todo
    }
}

let person = new Person(<Person>{ age:20, name:"John" });
person.someFunc();

key points:

  • Typescript 2.1 not required, Partial<T> not required
  • It supports functions (in comparison with simple type assertion which does not support functions)

Is there any way to call a function periodically in JavaScript?

function test() {
 alert('called!');
}
var id = setInterval('test();', 10000); //call test every 10 seconds.
function stop() { // call this to stop your interval.
   clearInterval(id);
}

Why the switch statement cannot be applied on strings?

That's because C++ turns switches into jump tables. It performs a trivial operation on the input data and jumps to the proper address without comparing. Since a string is not a number, but an array of numbers, C++ cannot create a jump table from it.

movf    INDEX,W     ; move the index value into the W (working) register from memory
addwf   PCL,F       ; add it to the program counter. each PIC instruction is one byte
                    ; so there is no need to perform any multiplication. 
                    ; Most architectures will transform the index in some way before 
                    ; adding it to the program counter

table                   ; the branch table begins here with this label
    goto    index_zero  ; each of these goto instructions is an unconditional branch
    goto    index_one   ; of code
    goto    index_two
    goto    index_three

index_zero
    ; code is added here to perform whatever action is required when INDEX = zero
    return

index_one
...

(code from wikipedia https://en.wikipedia.org/wiki/Branch_table)

Tracing XML request/responses with JAX-WS

Before starting tomcat, set JAVA_OPTS as below in Linux envs. Then start Tomcat. You will see the request and response in the catalina.out file.

export JAVA_OPTS="$JAVA_OPTS -Dcom.sun.xml.ws.transport.http.client.HttpTransportPipe.dump=true"

How to find the lowest common ancestor of two nodes in any binary tree?

This can be found at:- http://goursaha.freeoda.com/DataStructure/LowestCommonAncestor.html

 tree_node_type *LowestCommonAncestor(
 tree_node_type *root , tree_node_type *p , tree_node_type *q)
 {
     tree_node_type *l , *r , *temp;
     if(root==NULL)
     {
        return NULL;
     }

    if(root->left==p || root->left==q || root->right ==p || root->right ==q)
    {
        return root;
    }
    else
    {
        l=LowestCommonAncestor(root->left , p , q);
        r=LowestCommonAncestor(root->right , p, q);

        if(l!=NULL && r!=NULL)
        {
            return root;
        }
        else
        {
        temp = (l!=NULL)?l:r;
        return temp;
        }
    }
}

Phone Number Validation MVC

Try for simple regular expression for Mobile No

[Required (ErrorMessage="Required")]
[RegularExpression(@"^(\d{10})$", ErrorMessage = "Wrong mobile")]
public string Mobile { get; set; }

Algorithm/Data Structure Design Interview Questions

Follow up any question like this with: "How could you improve this code so the developer who maintains it can figure out how it works easily?"

Git On Custom SSH Port

When you want a relative path from your home directory (on any UNIX) you use this strange syntax:

ssh://[user@]host.xz[:port]/~[user]/path/to/repo

For Example, if the repo is in /home/jack/projects/jillweb on the server jill.com and you are logging in as jack with sshd listening on port 4242:

ssh://[email protected]:4242/~/projects/jillweb

And when logging in as jill (presuming you have file permissions):

ssh://[email protected]:4242/~jack/projects/jillweb

How to add values in a variable in Unix shell scripting?

In ksh ,bash ,sh:

$ count7=0                     
$ count1=5
$ 
$ (( count7 += count1 ))
$ echo $count7
$ 5

Utility of HTTP header "Content-Type: application/force-download" for mobile?

application/force-download is not a standard MIME type. It's a hack supported by some browsers, added fairly recently.

Your question doesn't really make any sense. It's like asking why Internet Explorer 4 doesn't support the latest CSS 3 functionality.

Shared folder between MacOSX and Windows on Virtual Box

You should map your virtual network drive in Windows.

  1. Open command prompt in Windows (VirtualBox)
  2. Execute: net use x: \\vboxsvr\<your_shared_folder_name>
  3. You should see new drive X: in My Computer

In your case execute net use x: \\vboxsvr\win7

How to obtain the last path segment of a URI

You can also use replaceAll:

String uri = "http://base_path/some_segment/id"
String lastSegment = uri.replaceAll(".*/", "")

System.out.println(lastSegment);

result:

id

Getting data posted in between two dates

if you want to force using BETWEEN keyword on Codeigniter query helper. You can use where without escape false like this code. Works well on CI version 3.1.5. Hope its help someone.

if(!empty($tglmin) && !empty($tglmax)){
        $this->db->group_start();
        $this->db->where('DATE(create_date) BETWEEN "'.$tglmin.'" AND "'.$tglmax.'"', '',false);
        $this->db->group_end();
    }

ApiNotActivatedMapError for simple html page using google-places-api

To enable Api do this

  1. Go to API Manager
  2. Click on Overview
  3. Search for Google Maps JavaScript API(Under Google Maps APIs). Click on that
  4. You will find Enable button there. Click to enable API.

OR You can try this url: Maps JavaScript API

Hope this will solve the problem of enabling API.

How can I print the contents of a hash in Perl?

Data::Dumper is your friend.

use Data::Dumper;
my %hash = ('abc' => 123, 'def' => [4,5,6]);
print Dumper(\%hash);

will output

$VAR1 = {
          'def' => [
                     4,
                     5,
                     6
                   ],
          'abc' => 123
        };

Find CRLF in Notepad++

Just do a \r with a find and replace with a blank in the replace field so everything goes up to one line. Then do a find and replace (in my case by semi colon) and replace with ;\n

:) -T&C

Converting a datetime string to timestamp in Javascript

Seems like the problem is with the date format.

 var d = "17-09-2013 10:08",
 dArr = d.split('-'),
 ts = new Date(dArr[1] + "-" + dArr[0] + "-" + dArr[2]).getTime(); // 1379392680000

How to automatically close cmd window after batch file execution?

I had this, I added EXIT and initially it didn't work, I guess per requiring the called program exiting advice mentioned in another response here, however it now works without further ado - not sure what's caused this, but the point to note is that I'm calling a data file .html rather than the program that handles it browser.exe, I did not edit anything else but suffice it to say it's much neater just using a bat file to access the main access pages of those web documents and only having title.bat, contents.bat, index.bat in the root folder with the rest of the content in a subfolder.

i.e.: contents.bat reads

cd subfolder
"contents.html"
exit

It also looks better if I change the bat file icons for just those items to suit the context they are in too, but that's another matter, hiding the bat files in the subfolder and creating custom icon shortcuts to them in the root folder with the images called for the customisation also hidden.

How can I add C++11 support to Code::Blocks compiler?

The answer with screenshots (put the checkbox as in the second pic, then press OK):

enter image description here enter image description here

Executing a stored procedure within a stored procedure

T-SQL is not asynchronous, so you really have no choice but to wait until SP2 ends. Luckily, that's what you want.

CREATE PROCEDURE SP1 AS
   EXEC SP2
   PRINT 'Done'

Using union and count(*) together in SQL query

If you have supporting indexes, and relatively high counts, something like this may be considerably faster than the solutions suggested:

SELECT name, MAX(Rcount) + MAX(Acount) AS TotalCount
FROM (
  SELECT name, COUNT(*) AS Rcount, 0 AS Acount
  FROM Results GROUP BY name
  UNION ALL
  SELECT name, 0, count(*)
  FROM Archive_Results
  GROUP BY name
) AS Both
GROUP BY name
ORDER BY name;

Log to the base 2 in python

In python 3 or above, math class has the following functions

import math

math.log2(x)
math.log10(x)
math.log1p(x)

or you can generally use math.log(x, base) for any base you want.

Close application and launch home screen on Android

Start the second activity with startActivityForResult and in the second activity return a value, that once in the onActivityResult method of the first activity closes the main application. I think this is the correct way Android does it.

UIWebView open links in Safari

One quick comment to user306253's answer: caution with this, when you try to load something in the UIWebView yourself (i.e. even from the code), this method will prevent it to happened.

What you can do to prevent this (thanks Wade) is:

if (inType == UIWebViewNavigationTypeLinkClicked) {
    [[UIApplication sharedApplication] openURL:[inRequest URL]];
    return NO;
}

return YES;

You might also want to handle the UIWebViewNavigationTypeFormSubmitted and UIWebViewNavigationTypeFormResubmitted types.

How to get the browser language using JavaScript

Try this script to get your browser language

_x000D_
_x000D_
<script type="text/javascript">_x000D_
var userLang = navigator.language || navigator.userLanguage; _x000D_
alert ("The language is: " + userLang);_x000D_
</script>
_x000D_
_x000D_
_x000D_

Cheers

Which is faster: Stack allocation or Heap allocation

Aside from the orders-of-magnitude performance advantage over heap allocation, stack allocation is preferable for long running server applications. Even the best managed heaps eventually get so fragmented that application performance degrades.

Android Studio - Failed to apply plugin [id 'com.android.application']

As in Accepted post, the problem solved with updating gradle to 4.4.1.

  1. Get Latest Gradle 4.4.1 from here
  2. Extract and put it in "C:\Program Files\Android\Android Studio\gradle"
  3. Then from android studio go to "File -> Settings -> Build, Excecution, Deployment -> Gradle", from Project-level settings: Select Use local gradle Distribution and give the above
    address(folder with name "gradle-4.4.1" in "C:\Program Files\ ...")
  4. Then make project.

enter image description here

My Problem solved this way.

JSON parsing using Gson for Java

You can use a separate class to represent the JSON object and use @SerializedName annotations to specify the field name to grab for each data member:

public class Response {

   @SerializedName("data")
   private Data data;

   private static class Data {
      @SerializedName("translations")
      public Translation[] translations;
   }

   private static class Translation {
      @SerializedName("translatedText")
      public String translatedText;
   }

   public String getTranslatedText() {
      return data.translations[0].translatedText;
   }
}

Then you can do the parsing in your parse() method using a Gson object:

Gson gson = new Gson();
Response response = gson.fromJson(jsonLine, Response.class);

System.out.println("Translated text: " + response.getTranslatedText());

With this approach, you can reuse the Response class to add any other additional fields to pick up other data members you might want to extract from JSON -- in case you want to make changes to get results for, say, multiple translations in one call, or to get an additional string for the detected source language.

Update UI from Thread in Android

If you use Handler (I see you do and hopefully you created its instance on the UI thread), then don't use runOnUiThread() inside of your runnable. runOnUiThread() is used when you do smth from a non-UI thread, however Handler will already execute your runnable on UI thread.

Try to do smth like this:

private Handler mHandler = new Handler();
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.gameone);
    res = getResources();
    // pB.setProgressDrawable(getResources().getDrawable(R.drawable.green)); **//Works**
    mHandler.postDelayed(runnable, 1);
}

private Runnable runnable = new Runnable() {
    public void run() {
        pB.setProgressDrawable(getResources().getDrawable(R.drawable.green));
        pB.invalidate(); // maybe this will even not needed - try to comment out
    }
};

How do I view the SSIS packages in SQL Server Management Studio?

If you deployed the package to the "Integration Services Catalog" on SSMS you can retrieve the package using Visual studio.

enter image description here

Error Message: Type or namespace definition, or end-of-file expected

You have extra brackets in Hours property;

public  object Hours { get; set; }}

Run a single test method with maven

To run a single test method in Maven, you need to provide the command as:

mvn test -Dtest=TestCircle#xyz test

where TestCircle is the test class name and xyz is the test method.

Wild card characters also work; both in the method name and class name.

If you're testing in a multi-module project, specify the module that the test is in with -pl <module-name>.

For integration tests use it.test=... option instead of test=...:

mvn -pl <module-name> -Dit.test=TestCircle#xyz integration-test

How to pass in parameters when use resource service?

I suggest you to use provider. Provide is good when you want to configure it first before to use (against Service/Factory)

Something like:

.provider('Magazines', function() {

    this.url = '/';
    this.urlArray = '/';
    this.organId = 'Default';

    this.$get = function() {
        var url = this.url;
        var urlArray = this.urlArray;
        var organId = this.organId;

        return {
            invoke: function() {
                return ......
            }
        }
    };

    this.setUrl  = function(url) {
        this.url = url;
    };

   this.setUrlArray  = function(urlArray) {
        this.urlArray = urlArray;
    };

    this.setOrganId  = function(organId) {
        this.organId = organId;
    };
});

.config(function(MagazinesProvider){
    MagazinesProvider.setUrl('...');
    MagazinesProvider.setUrlArray('...');
    MagazinesProvider.setOrganId('...');
});

And now controller:

function MyCtrl($scope, Magazines) {        

        Magazines.invoke();

       ....

}

laravel Unable to prepare route ... for serialization. Uses Closure

check that your web.php file has this extension

use Illuminate\Support\Facades\Route;

my problem gone fixed by this way.

How to close IPython Notebook properly?

I think accepted answer outdated and is not valid anymore.

You can terminate jupyter notebook from web interface on file menü item.

enter image description here

When you move Mouse cursor on "close and halt", you will see following explanation.

enter image description here

And when you click "close and halt", you will see following message on terminal screen.

enter image description here

Can I embed a custom font in an iPhone application?

It's not out yet, but the next version of cocos2d (2d game framework) will support variable length bitmap fonts as character maps.

http://code.google.com/p/cocos2d-iphone/issues/detail?id=317

The author doesn't have a nailed down release date for this version, but I did see a posting that indicated it would be in the next month or two.

Make an image follow mouse pointer

Here's my code (not optimized but a full working example):

<head>
<style>
#divtoshow {position:absolute;display:none;color:white;background-color:black}
#onme {width:150px;height:80px;background-color:yellow;cursor:pointer}
</style>
<script type="text/javascript">
var divName = 'divtoshow'; // div that is to follow the mouse (must be position:absolute)
var offX = 15;          // X offset from mouse position
var offY = 15;          // Y offset from mouse position

function mouseX(evt) {if (!evt) evt = window.event; if (evt.pageX) return evt.pageX; else if (evt.clientX)return evt.clientX + (document.documentElement.scrollLeft ?  document.documentElement.scrollLeft : document.body.scrollLeft); else return 0;}
function mouseY(evt) {if (!evt) evt = window.event; if (evt.pageY) return evt.pageY; else if (evt.clientY)return evt.clientY + (document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop); else return 0;}

function follow(evt) {
    var obj = document.getElementById(divName).style;
    obj.left = (parseInt(mouseX(evt))+offX) + 'px';
    obj.top = (parseInt(mouseY(evt))+offY) + 'px'; 
    }
document.onmousemove = follow;
</script>
</head>
<body>
<div id="divtoshow">test</div>
<br><br>
<div id='onme' onMouseover='document.getElementById(divName).style.display="block"' onMouseout='document.getElementById(divName).style.display="none"'>Mouse over this</div>
</body>

How do I set a program to launch at startup

    /// <summary>
    /// Add application to Startup of windows
    /// </summary>
    /// <param name="appName"></param>
    /// <param name="path"></param>
    public static void AddStartup(string appName, string path)
    {
        using (RegistryKey key = Registry.CurrentUser.OpenSubKey
            ("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true))
        {
            key.SetValue(appName, "\"" + path + "\"");
        }
    }

    /// <summary>
    /// Remove application from Startup of windows
    /// </summary>
    /// <param name="appName"></param>
    public static void RemoveStartup(string appName)
    {
        using (RegistryKey key = Registry.CurrentUser.OpenSubKey
            ("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true))
        {
            key.DeleteValue(appName, false);
        }
    }

How to convert numpy arrays to standard TensorFlow format?

You can use tf.convert_to_tensor():

import tensorflow as tf
import numpy as np

data = [[1,2,3],[4,5,6]]
data_np = np.asarray(data, np.float32)

data_tf = tf.convert_to_tensor(data_np, np.float32)

sess = tf.InteractiveSession()  
print(data_tf.eval())

sess.close()

Here's a link to the documentation for this method:

https://www.tensorflow.org/api_docs/python/tf/convert_to_tensor

RegEx for matching UK Postcodes

Most of the answers here didn't work for all the postcodes I have in my database. I finally found one that validates with all, using the new regex provided by the government:

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/413338/Bulk_Data_Transfer_-_additional_validation_valid_from_March_2015.pdf

It isn't in any of the previous answers so I post it here in case they take the link down:

^([Gg][Ii][Rr] 0[Aa]{2})|((([A-Za-z][0-9]{1,2})|(([A-Za-z][A-Ha-hJ-Yj-y][0-9]{1,2})|(([A-Za-z][0-9][A-Za-z])|([A-Za-z][A-Ha-hJ-Yj-y][0-9]?[A-Za-z])))) [0-9][A-Za-z]{2})$

UPDATE: Updated regex as pointed by Jamie Bull. Not sure if it was my error copying or it was an error in the government's regex, the link is down now...

UPDATE: As ctwheels found, this regex works with the javascript regex flavor. See his comment for one that works with the pcre (php) flavor.

How to assign bean's property an Enum value in Spring config file?

Spring-integration example, routing based on a an Enum field:

public class BookOrder {

    public enum OrderType { DELIVERY, PICKUP } //enum
    public BookOrder(..., OrderType orderType) //orderType
    ...

config:

<router expression="payload.orderType" input-channel="processOrder">
    <mapping value="DELIVERY" channel="delivery"/>
    <mapping value="PICKUP" channel="pickup"/>
</router>

What's the meaning of System.out.println in Java?

Because out is being called with the System class name itself, not an instance of a class (an object), So out must be a static variable belonging to the class System. out must be instance of a class, because it is invoking the method println().

// the System class belongs to java.lang package
class System {
    public static final PrintStream out;
}
class PrintStream {
    public void println();
}

What are all the different ways to create an object in Java?

Within the Java language, the only way to create an object is by calling its constructor, be it explicitly or implicitly. Using reflection results in a call to the constructor method, deserialization uses reflection to call the constructor, factory methods wrap the call to the constructor to abstract the actual construction and cloning is similarly a wrapped constructor call.

unary operator expected in shell script when comparing null value with string

Since the value of $var is the empty string, this:

if [ $var == $var1 ]; then

expands to this:

if [ == abcd ]; then

which is a syntax error.

You need to quote the arguments:

if [ "$var" == "$var1" ]; then

You can also use = rather than ==; that's the original syntax, and it's a bit more portable.

If you're using bash, you can use the [[ syntax, which doesn't require the quotes:

if [[ $var = $var1 ]]; then

Even then, it doesn't hurt to quote the variable reference, and adding quotes:

if [[ "$var" = "$var1" ]]; then

might save a future reader a moment trying to remember whether [[ ... ]] requires them.

Postgresql Select rows where column = array

   $array[0] = 1;
   $array[2] = 2;
   $arrayTxt = implode( ',', $array);
   $sql = "SELECT * FROM table WHERE some_id in ($arrayTxt)"

Triggering a checkbox value changed event in DataGridView

cellEndEditTimer.Start();

this line makes the datagridview update the list of checked boxes

Thank you.

Vim: faster way to select blocks of text in visual mode

v%

will select the whole block.

Play with also:

v}, vp, vs, etc.

See help:

:help text-objects

which lists the different ways to select letters, words, sentences, paragraphs, blocks, and so on.

Angularjs ng-model doesn't work inside ng-if

The ng-if directive, like other directives creates a child scope. See the script below (or this jsfiddle)

_x000D_
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.min.js"></script>_x000D_
_x000D_
<script>_x000D_
    function main($scope) {_x000D_
        $scope.testa = false;_x000D_
        $scope.testb = false;_x000D_
        $scope.testc = false;_x000D_
        $scope.obj = {test: false};_x000D_
    }_x000D_
</script>_x000D_
_x000D_
<div ng-app >_x000D_
    <div ng-controller="main">_x000D_
        _x000D_
        Test A: {{testa}}<br />_x000D_
        Test B: {{testb}}<br />_x000D_
        Test C: {{testc}}<br />_x000D_
        {{obj.test}}_x000D_
        _x000D_
        <div>_x000D_
            testa (without ng-if): <input type="checkbox" ng-model="testa" />_x000D_
        </div>_x000D_
        <div ng-if="!testa">_x000D_
            testb (with ng-if): <input type="checkbox" ng-model="testb" /> {{testb}}_x000D_
        </div>_x000D_
        <div ng-if="!someothervar">_x000D_
            testc (with ng-if): <input type="checkbox" ng-model="testc" />_x000D_
        </div>_x000D_
        <div ng-if="!someothervar">_x000D_
            object (with ng-if): <input type="checkbox" ng-model="obj.test" />_x000D_
        </div>_x000D_
        _x000D_
    </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

So, your checkbox changes the testb inside of the child scope, but not the outer parent scope.

Note, that if you want to modify the data in the parent scope, you'll need to modify the internal properties of an object like in the last div that I added.

Python time measure function

Timeit has two big flaws: it doesn't return the return value of the function, and it uses eval, which requires passing in extra setup code for imports. This solves both problems simply and elegantly:

def timed(f):
  start = time.time()
  ret = f()
  elapsed = time.time() - start
  return ret, elapsed

timed(lambda: database.foo.execute('select count(*) from source.apachelog'))
(<sqlalchemy.engine.result.ResultProxy object at 0x7fd6c20fc690>, 4.07547402381897)

Insert Data Into Temp Table with Query

SELECT * INTO #TempTable 
FROM SampleTable
WHERE...

SELECT * FROM #TempTable
DROP TABLE #TempTable

correct quoting for cmd.exe for multiple arguments

Spaces are horrible in filenames or directory names.

The correct syntax for this is to include every directory name that includes spaces, in double quotes

cmd /c C:\"Program Files"\"Microsoft Visual Studio 9.0"\Common7\IDE\devenv.com mysolution.sln /build "release|win32"

C++ compile error: has initializer but incomplete type

You need this include:

#include <sstream>

How to redirect the output of print to a TXT file

Usinge the file argument in the print function, you can have different files per print:

print('Redirect output to file', file=open('/tmp/example.log', 'w'))

How do I use sudo to redirect output to a location I don't have permission to write to?

Whenever I have to do something like this I just become root:

# sudo -s
# ls -hal /root/ > /root/test.out
# exit

It's probably not the best way, but it works.

How to create a drop-down list?

Try this:

package example.spin.spinnerexample;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener{

    String[] bankNames={"BOI","SBI","HDFC","PNB","OBC"};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //Getting the instance of Spinner and applying OnItemSelectedListener on it
        Spinner spin = (Spinner) findViewById(R.id.simpleSpinner);
        spin.setOnItemSelectedListener(this);

        //Creating the ArrayAdapter instance having the bank name list
        ArrayAdapter aa = new ArrayAdapter(this,android.R.layout.simple_spinner_item,bankNames);
        aa.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        //Setting the ArrayAdapter data on the Spinner
        spin.setAdapter(aa);
    }


    //Performing action onItemSelected and onNothing selected
    @Override
    public void onItemSelected(AdapterView<?> arg0, View arg1, int position,long id) {
        Toast.makeText(getApplicationContext(), bankNames[position], Toast.LENGTH_LONG).show();
    }

    @Override
    public void onNothingSelected(AdapterView<?> arg0) {
        // TODO Auto-generated method stub

    }
}

activity_main.xml:-

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity">

    <Spinner
        android:id="@+id/simpleSpinner"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="100dp" />

</RelativeLayout>

How to read text file in JavaScript

Javascript doesn't have access to the user's filesystem for security reasons. FileReader is only for files manually selected by the user.

DB2 Timestamp select statement

You might want to use TRUNC function on your column when comparing with string format, so it compares only till seconds, not milliseconds.

SELECT * FROM <table_name> WHERE id = 1 
AND TRUNC(usagetime, 'SS') = '2012-09-03 08:03:06';

If you wanted to truncate upto minutes, hours, etc. that is also possible, just use appropriate notation instead of 'SS':

hour ('HH'), minute('MI'), year('YEAR' or 'YYYY'), month('MONTH' or 'MM'), Day ('DD')

How to remove decimal values from a value of type 'double' in Java

Try:

String newValue = String.format("%d", (int)d);

How do I print the type or class of a variable in Swift?

You can use reflect to get information about object.
For example name of object class:

var classname = reflect(now).summary

ASP.NET 4.5 has not been registered on the Web server

tl;dr; Clicking OK is the workaround, everything will work fine after that.

I also received this error message.

Configuring Web http://localhost:xxxxx/ for ASP.NET 4.5 failed. You must manually configure this site for ASP.NET 4.5 in order for the site to run correctly. ASP.NET 4.0 has not been registered on the Web server. You need to manually configure your Web server for ASP.NET 4.0 in order for your site to run correctly.

Environment: Windows 10, IIS8, VS 2012 Web.

After finding this page, along with several seemingly invasive solutions, I read through the hotfix option at https://support.microsoft.com/en-us/help/3002339/unexpected-dialog-box-appears-when-you-open-projects-in-visual-studio as suggested here.

Please avoid doing anything too drastic, and note the section of that page marked "Workaround" as shown below:

Workaround


To work around this issue, click OK when the dialog box appears after you either create a new project or open an existing Web Site Project or Windows Azure project. After you do this, the project works as expected.

In other words, click OK on the dialog box one time, and the message is gone forever. The project will work just fine.

Keep a line of text as a single line - wrap the whole line or none at all

You can use white-space: nowrap; to define this behaviour:

// HTML:

_x000D_
_x000D_
.nowrap {_x000D_
  white-space: nowrap ;_x000D_
}
_x000D_
<p>_x000D_
      <span class="nowrap">How do I wrap this line of text</span>_x000D_
      <span class="nowrap">- asked by Peter 2 days ago</span>_x000D_
    </p>
_x000D_
_x000D_
_x000D_

// CSS:
.nowrap {
  white-space: nowrap ;
}

Java JTable getting the data of the selected row

http://docs.oracle.com/javase/7/docs/api/javax/swing/JTable.html

You will find these methods in it:

getValueAt(int row, int column)
getSelectedRow()
getSelectedColumn()

Use a mix of these to achieve your result.

Convert NULL to empty string - Conversion failed when converting from a character string to uniqueidentifier

Select ID, IsNull(Cast(ParentID as varchar(max)),'') from Patients

This is needed because field ParentID is not varchar/nvarchar type. This will do the trick:

Select ID, IsNull(ParentID,'') from Patients

Disable elastic scrolling in Safari

You could check if the scroll-offsets are in the bounds. If they go beyond, set them back.

var scrollX = 0;
var scrollY = 0;
var scrollMinX = 0;
var scrollMinY = 0;
var scrollMaxX = document.body.scrollWidth - window.innerWidth;
var scrollMaxY = document.body.scrollHeight - window.innerHeight;

// make sure that we work with the correct dimensions
window.addEventListener('resize', function () {
  scrollMaxX = document.body.scrollWidth - window.innerWidth;
  scrollMaxY = document.body.scrollHeight - window.innerHeight;
}, false);

// where the magic happens
window.addEventListener('scroll', function () {
  scrollX = window.scrollX;
  scrollY = window.scrollY;

  if (scrollX <= scrollMinX) scrollTo(scrollMinX, window.scrollY);
  if (scrollX >= scrollMaxX) scrollTo(scrollMaxX, window.scrollY);

  if (scrollY <= scrollMinY) scrollTo(window.scrollX, scrollMinY);
  if (scrollY >= scrollMaxY) scrollTo(window.scrollX, scrollMaxY);
}, false);

http://jsfiddle.net/yckart/3YnUM/

"Invalid JSON primitive" in Ajax processing

it's working something like this

data: JSON.stringify({'id':x}),

C# "No suitable method found to override." -- but there is one

You cannot override a function with different parameters, only you are allowed to change the functionality of the overridden method.

//Compiler Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

//Overriding & overloading

namespace polymorpism
{
    public class Program
    {
        public static void Main(string[] args)
        {

            drowButn calobj = new drowButn();

            BtnOverride calobjOvrid = new BtnOverride();

            Console.WriteLine(calobj.btn(5.2, 6.6).ToString());

            //btn has compleately overrided inside this calobjOvrid object
            Console.WriteLine(calobjOvrid.btn(5.2, 6.6).ToString());
            //the overloaded function
            Console.WriteLine(calobjOvrid.btn(new double[] { 5.2, 6.6 }).ToString());

            Console.ReadKey();
        }
    }

    public class drowButn
    {

        //same add function overloading to add double type field inputs
        public virtual double btn(double num1, double num2)
        {

            return (num1 + num2);

        }


    }

    public class BtnOverride : drowButn
    {

        //same add function overrided and change its functionality 
        //(this will compleately replace the base class function
        public override double btn(double num1, double num2)
        {
            //do compleatly diffarant function then the base class
            return (num1 * num2);

        }

        //same function overloaded (no override keyword used) 
        // this will not effect the base class function

        public double btn(double[] num)
        {
            double cal = 0;

            foreach (double elmnt in num)
            {

                cal += elmnt;
            }
            return cal;

        }
    }
}

In SQL how to compare date values?

You could add the time component

WHERE mydate<='2008-11-25 23:59:59'

but that might fail on DST switchover dates if mydate is '2008-11-25 24:59:59', so it's probably safest to grab everything before the next date:

WHERE mydate < '2008-11-26 00:00:00'

in_array() and multidimensional array

Since PHP 5.6 there is a better and cleaner solution for the original answer :

With a multidimensional array like this :

$a = array(array("Mac", "NT"), array("Irix", "Linux"))

We can use the splat operator :

return in_array("Irix", array_merge(...$a), true)

If you have string keys like this :

$a = array("a" => array("Mac", "NT"), "b" => array("Irix", "Linux"))

You will have to use array_values in order to avoid the error Cannot unpack array with string keys :

return in_array("Irix", array_merge(...array_values($a)), true)

What is the most appropriate way to store user settings in Android application

I agree with Reto and fiXedd. Objectively speaking it doesn't make a lot of sense investing significant time and effort into encrypting passwords in SharedPreferences since any attacker that has access to your preferences file is fairly likely to also have access to your application's binary, and therefore the keys to unencrypt the password.

However, that being said, there does seem to be a publicity initiative going on identifying mobile applications that store their passwords in cleartext in SharedPreferences and shining unfavorable light on those applications. See http://blogs.wsj.com/digits/2011/06/08/some-top-apps-put-data-at-risk/ and http://viaforensics.com/appwatchdog for some examples.

While we need more attention paid to security in general, I would argue that this sort of attention on this one particular issue doesn't actually significantly increase our overall security. However, perceptions being as they are, here's a solution to encrypt the data you place in SharedPreferences.

Simply wrap your own SharedPreferences object in this one, and any data you read/write will be automatically encrypted and decrypted. eg.

final SharedPreferences prefs = new ObscuredSharedPreferences( 
    this, this.getSharedPreferences(MY_PREFS_FILE_NAME, Context.MODE_PRIVATE) );

// eg.    
prefs.edit().putString("foo","bar").commit();
prefs.getString("foo", null);

Here's the code for the class:

/**
 * Warning, this gives a false sense of security.  If an attacker has enough access to
 * acquire your password store, then he almost certainly has enough access to acquire your
 * source binary and figure out your encryption key.  However, it will prevent casual
 * investigators from acquiring passwords, and thereby may prevent undesired negative
 * publicity.
 */
public class ObscuredSharedPreferences implements SharedPreferences {
    protected static final String UTF8 = "utf-8";
    private static final char[] SEKRIT = ... ; // INSERT A RANDOM PASSWORD HERE.
                                               // Don't use anything you wouldn't want to
                                               // get out there if someone decompiled
                                               // your app.


    protected SharedPreferences delegate;
    protected Context context;

    public ObscuredSharedPreferences(Context context, SharedPreferences delegate) {
        this.delegate = delegate;
        this.context = context;
    }

    public class Editor implements SharedPreferences.Editor {
        protected SharedPreferences.Editor delegate;

        public Editor() {
            this.delegate = ObscuredSharedPreferences.this.delegate.edit();                    
        }

        @Override
        public Editor putBoolean(String key, boolean value) {
            delegate.putString(key, encrypt(Boolean.toString(value)));
            return this;
        }

        @Override
        public Editor putFloat(String key, float value) {
            delegate.putString(key, encrypt(Float.toString(value)));
            return this;
        }

        @Override
        public Editor putInt(String key, int value) {
            delegate.putString(key, encrypt(Integer.toString(value)));
            return this;
        }

        @Override
        public Editor putLong(String key, long value) {
            delegate.putString(key, encrypt(Long.toString(value)));
            return this;
        }

        @Override
        public Editor putString(String key, String value) {
            delegate.putString(key, encrypt(value));
            return this;
        }

        @Override
        public void apply() {
            delegate.apply();
        }

        @Override
        public Editor clear() {
            delegate.clear();
            return this;
        }

        @Override
        public boolean commit() {
            return delegate.commit();
        }

        @Override
        public Editor remove(String s) {
            delegate.remove(s);
            return this;
        }
    }

    public Editor edit() {
        return new Editor();
    }


    @Override
    public Map<String, ?> getAll() {
        throw new UnsupportedOperationException(); // left as an exercise to the reader
    }

    @Override
    public boolean getBoolean(String key, boolean defValue) {
        final String v = delegate.getString(key, null);
        return v!=null ? Boolean.parseBoolean(decrypt(v)) : defValue;
    }

    @Override
    public float getFloat(String key, float defValue) {
        final String v = delegate.getString(key, null);
        return v!=null ? Float.parseFloat(decrypt(v)) : defValue;
    }

    @Override
    public int getInt(String key, int defValue) {
        final String v = delegate.getString(key, null);
        return v!=null ? Integer.parseInt(decrypt(v)) : defValue;
    }

    @Override
    public long getLong(String key, long defValue) {
        final String v = delegate.getString(key, null);
        return v!=null ? Long.parseLong(decrypt(v)) : defValue;
    }

    @Override
    public String getString(String key, String defValue) {
        final String v = delegate.getString(key, null);
        return v != null ? decrypt(v) : defValue;
    }

    @Override
    public boolean contains(String s) {
        return delegate.contains(s);
    }

    @Override
    public void registerOnSharedPreferenceChangeListener(OnSharedPreferenceChangeListener onSharedPreferenceChangeListener) {
        delegate.registerOnSharedPreferenceChangeListener(onSharedPreferenceChangeListener);
    }

    @Override
    public void unregisterOnSharedPreferenceChangeListener(OnSharedPreferenceChangeListener onSharedPreferenceChangeListener) {
        delegate.unregisterOnSharedPreferenceChangeListener(onSharedPreferenceChangeListener);
    }




    protected String encrypt( String value ) {

        try {
            final byte[] bytes = value!=null ? value.getBytes(UTF8) : new byte[0];
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
            SecretKey key = keyFactory.generateSecret(new PBEKeySpec(SEKRIT));
            Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
            pbeCipher.init(Cipher.ENCRYPT_MODE, key, new PBEParameterSpec(Settings.Secure.getString(context.getContentResolver(),Settings.Secure.ANDROID_ID).getBytes(UTF8), 20));
            return new String(Base64.encode(pbeCipher.doFinal(bytes), Base64.NO_WRAP),UTF8);

        } catch( Exception e ) {
            throw new RuntimeException(e);
        }

    }

    protected String decrypt(String value){
        try {
            final byte[] bytes = value!=null ? Base64.decode(value,Base64.DEFAULT) : new byte[0];
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
            SecretKey key = keyFactory.generateSecret(new PBEKeySpec(SEKRIT));
            Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
            pbeCipher.init(Cipher.DECRYPT_MODE, key, new PBEParameterSpec(Settings.Secure.getString(context.getContentResolver(),Settings.Secure.ANDROID_ID).getBytes(UTF8), 20));
            return new String(pbeCipher.doFinal(bytes),UTF8);

        } catch( Exception e) {
            throw new RuntimeException(e);
        }
    }

}

MySQL pivot table query with dynamic columns

The only way in MySQL to do this dynamically is with Prepared statements. Here is a good article about them:

Dynamic pivot tables (transform rows to columns)

Your code would look like this:

SET @sql = NULL;
SELECT
  GROUP_CONCAT(DISTINCT
    CONCAT(
      'MAX(IF(pa.fieldname = ''',
      fieldname,
      ''', pa.fieldvalue, NULL)) AS ',
      fieldname
    )
  ) INTO @sql
FROM product_additional;

SET @sql = CONCAT('SELECT p.id
                    , p.name
                    , p.description, ', @sql, ' 
                   FROM product p
                   LEFT JOIN product_additional AS pa 
                    ON p.id = pa.id
                   GROUP BY p.id');

PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

See Demo

NOTE: GROUP_CONCAT function has a limit of 1024 characters. See parameter group_concat_max_len

Rotating a Vector in 3D Space

If you want to rotate a vector you should construct what is known as a rotation matrix.

Rotation in 2D

Say you want to rotate a vector or a point by ?, then trigonometry states that the new coordinates are

    x' = x cos ? - y sin ?
    y' = x sin ? + y cos ?

To demo this, let's take the cardinal axes X and Y; when we rotate the X-axis 90° counter-clockwise, we should end up with the X-axis transformed into Y-axis. Consider

    Unit vector along X axis = <1, 0>
    x' = 1 cos 90 - 0 sin 90 = 0
    y' = 1 sin 90 + 0 cos 90 = 1
    New coordinates of the vector, <x', y'> = <0, 1>  ?  Y-axis

When you understand this, creating a matrix to do this becomes simple. A matrix is just a mathematical tool to perform this in a comfortable, generalized manner so that various transformations like rotation, scale and translation (moving) can be combined and performed in a single step, using one common method. From linear algebra, to rotate a point or vector in 2D, the matrix to be built is

    |cos ?   -sin ?| |x| = |x cos ? - y sin ?| = |x'|
    |sin ?    cos ?| |y|   |x sin ? + y cos ?|   |y'|

Rotation in 3D

That works in 2D, while in 3D we need to take in to account the third axis. Rotating a vector around the origin (a point) in 2D simply means rotating it around the Z-axis (a line) in 3D; since we're rotating around Z-axis, its coordinate should be kept constant i.e. 0° (rotation happens on the XY plane in 3D). In 3D rotating around the Z-axis would be

    |cos ?   -sin ?   0| |x|   |x cos ? - y sin ?|   |x'|
    |sin ?    cos ?   0| |y| = |x sin ? + y cos ?| = |y'|
    |  0       0      1| |z|   |        z        |   |z'|

around the Y-axis would be

    | cos ?    0   sin ?| |x|   | x cos ? + z sin ?|   |x'|
    |   0      1       0| |y| = |         y        | = |y'|
    |-sin ?    0   cos ?| |z|   |-x sin ? + z cos ?|   |z'|

around the X-axis would be

    |1     0           0| |x|   |        x        |   |x'|
    |0   cos ?    -sin ?| |y| = |y cos ? - z sin ?| = |y'|
    |0   sin ?     cos ?| |z|   |y sin ? + z cos ?|   |z'|

Note 1: axis around which rotation is done has no sine or cosine elements in the matrix.

Note 2: This method of performing rotations follows the Euler angle rotation system, which is simple to teach and easy to grasp. This works perfectly fine for 2D and for simple 3D cases; but when rotation needs to be performed around all three axes at the same time then Euler angles may not be sufficient due to an inherent deficiency in this system which manifests itself as Gimbal lock. People resort to Quaternions in such situations, which is more advanced than this but doesn't suffer from Gimbal locks when used correctly.

I hope this clarifies basic rotation.

Rotation not Revolution

The aforementioned matrices rotate an object at a distance r = v(x² + y²) from the origin along a circle of radius r; lookup polar coordinates to know why. This rotation will be with respect to the world space origin a.k.a revolution. Usually we need to rotate an object around its own frame/pivot and not around the world's i.e. local origin. This can also be seen as a special case where r = 0. Since not all objects are at the world origin, simply rotating using these matrices will not give the desired result of rotating around the object's own frame. You'd first translate (move) the object to world origin (so that the object's origin would align with the world's, thereby making r = 0), perform the rotation with one (or more) of these matrices and then translate it back again to its previous location. The order in which the transforms are applied matters. Combining multiple transforms together is called concatenation or composition.

Composition

I urge you to read about linear and affine transformations and their composition to perform multiple transformations in one shot, before playing with transformations in code. Without understanding the basic maths behind it, debugging transformations would be a nightmare. I found this lecture video to be a very good resource. Another resource is this tutorial on transformations that aims to be intuitive and illustrates the ideas with animation (caveat: authored by me!).

Rotation around Arbitrary Vector

A product of the aforementioned matrices should be enough if you only need rotations around cardinal axes (X, Y or Z) like in the question posted. However, in many situations you might want to rotate around an arbitrary axis/vector. The Rodrigues' formula (a.k.a. axis-angle formula) is a commonly prescribed solution to this problem. However, resort to it only if you’re stuck with just vectors and matrices. If you're using Quaternions, just build a quaternion with the required vector and angle. Quaternions are a superior alternative for storing and manipulating 3D rotations; it's compact and fast e.g. concatenating two rotations in axis-angle representation is fairly expensive, moderate with matrices but cheap in quaternions. Usually all rotation manipulations are done with quaternions and as the last step converted to matrices when uploading to the rendering pipeline. See Understanding Quaternions for a decent primer on quaternions.

How to call one shell script from another shell script?

If you have another file in same directory, you can either do:

bash another_script.sh

or

source another_script.sh

or

. another_script.sh

When you use bash instead of source, the script cannot alter environment of the parent script. The . command is POSIX standard while source command is a more readable bash synonym for . (I prefer source over .). If your script resides elsewhere just provide path to that script. Both relative as well as full path should work.

Reducing the gap between a bullet and text in a list item

Try this....

ul.list-group li {
     padding-left: 13px;
     position: relative;
}

ul.list-group li:before {
     left: 0 !important;
     position: absolute;
}

How to edit nginx.conf to increase file size upload

First Navigate the Path of php.ini

sudo vi /etc/php/7.2/fpm/php.ini

then, next change

upload_max_filesize = 999M
post_max_size = 999M

then ESC-->:wq

Now Lastly Paste this command,

sudo systemctl restart php7.2-fpm.service

you are done.

Linq select to new object

All of the grouped objects, or all of the types? It sounds like you may just want:

var query = types.GroupBy(t => t.Type)
                 .Select(g => new { Type = g.Key, Count = g.Count() });

foreach (var result in query)
{
    Console.WriteLine("{0}, {1}", result.Type, result.Count);
}

EDIT: If you want it in a dictionary, you can just use:

var query = types.GroupBy(t => t.Type)
                 .ToDictionary(g => g.Key, g => g.Count());

There's no need to select into pairs and then build the dictionary.

Using Chrome, how to find to which events are bound to an element

You can also use Chrome's inspector to find attached events another way, as follows:

  1. Right click on the element to inspect, or find it in the 'Elements' pane.
  2. Then in the 'Event Listeners' tab/pane, expand the event (eg 'click')
  3. Expand the various sub-nodes to find the one you want, and then look for where the 'handler' sub-node is.
  4. Right click the word 'function', and then click 'Show function definition'

This will take you to where the handler was defined, as demonstrated in the following image, and explained by Paul Irish here: https://groups.google.com/forum/#!topic/google-chrome-developer-tools/NTcIS15uigA

'Show Function definition'

How to position a div in the middle of the screen when the page is bigger than the screen

Short answer, Just add position:fixed and that will solve your problem

Google Maps: Auto close open InfoWindows?

There is a easier way besides using the close() function. if you create a variable with the InfoWindow property it closes automatically when you open another.

var info_window;
var map;
var chicago = new google.maps.LatLng(33.84659, -84.35686);

function initialize() {
    var mapOptions = {
        center: chicago,
        zoom: 14,
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);

    info_window = new google.maps.InfoWindow({
        content: 'loading'
    )};

createLocationOnMap('Location Name 1', new google.maps.LatLng(33.84659, -84.35686), '<p><strong>Location Name 1</strong><br/>Address 1</p>');
createLocationOnMap('Location Name 2', new google.maps.LatLng(33.84625, -84.36212), '<p><strong>Location Name 1</strong><br/>Address 2</p>');

}

function createLocationOnMap(titulo, posicao, conteudo) {            
    var m = new google.maps.Marker({
        map: map,
        animation: google.maps.Animation.DROP,
        title: titulo,
        position: posicao,
        html: conteudo
    });            

    google.maps.event.addListener(m, 'click', function () {                
        info_window.setContent(this.html);
        info_window.open(map, this);
    });
}

Java: How to convert a File object to a String object in java?

Readin file with file inputstream and append file content to string.

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;

public class CopyOffileInputStream {

    public static void main(String[] args) {

        //File file = new File("./store/robots.txt");
        File file = new File("swingloggingsscce.log");

        FileInputStream fis = null;
        String str = "";

        try {
            fis = new FileInputStream(file);
            int content;
            while ((content = fis.read()) != -1) {
                // convert to char and display it
                str += (char) content;
            }

            System.out.println("After reading file");
            System.out.println(str);

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (fis != null)
                    fis.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }
}

How to make "if not true condition"?

This one

if [[ !  $(cat /etc/passwd | grep "sysa") ]]
Then echo " something"
exit 2
fi

Uploading Files in ASP.net without using the FileUpload server control

//create a folder in server (~/Uploads)
 //to upload
 File.Copy(@"D:\CORREO.txt", Server.MapPath("~/Uploads/CORREO.txt"));

 //to download
             Response.ContentType = ContentType;
             Response.AppendHeader("Content-Disposition", "attachment;filename=" + Path.GetFileName("~/Uploads/CORREO.txt"));
             Response.WriteFile("~/Uploads/CORREO.txt");
             Response.End();

Regex to match only letters

Regular expression which few people has written as "/^[a-zA-Z]$/i" is not correct because at the last they have mentioned /i which is for case insensitive and after matching for first time it will return back. Instead of /i just use /g which is for global and you also do not have any need to put ^ $ for starting and ending.

/[a-zA-Z]+/g
  1. [a-z_]+ match a single character present in the list below
  2. Quantifier: + Between one and unlimited times, as many times as possible, giving back as needed
  3. a-z a single character in the range between a and z (case sensitive)
  4. A-Z a single character in the range between A and Z (case sensitive)
  5. g modifier: global. All matches (don't return on first match)

How to schedule a periodic task in Java?

Have you tried Spring Scheduler using annotations ?

@Scheduled(cron = "0 0 0/8 ? * * *")
public void scheduledMethodNoReturnValue(){
    //body can be another method call which returns some value.
}

you can do this with xml as well.

 <task:scheduled-tasks>
   <task:scheduled ref = "reference" method = "methodName" cron = "<cron expression here> -or- ${<cron expression from property files>}"
 <task:scheduled-tasks>

A simple explanation of Naive Bayes Classification

Ram Narasimhan explained the concept very nicely here below is an alternative explanation through the code example of Naive Bayes in action
It uses an example problem from this book on page 351
This is the data set that we will be using
enter image description here
In the above dataset if we give the hypothesis = {"Age":'<=30', "Income":"medium", "Student":'yes' , "Creadit_Rating":'fair'} then what is the probability that he will buy or will not buy a computer.
The code below exactly answers that question.
Just create a file called named new_dataset.csv and paste the following content.

Age,Income,Student,Creadit_Rating,Buys_Computer
<=30,high,no,fair,no
<=30,high,no,excellent,no
31-40,high,no,fair,yes
>40,medium,no,fair,yes
>40,low,yes,fair,yes
>40,low,yes,excellent,no
31-40,low,yes,excellent,yes
<=30,medium,no,fair,no
<=30,low,yes,fair,yes
>40,medium,yes,fair,yes
<=30,medium,yes,excellent,yes
31-40,medium,no,excellent,yes
31-40,high,yes,fair,yes
>40,medium,no,excellent,no

Here is the code the comments explains everything we are doing here! [python]

import pandas as pd 
import pprint 

class Classifier():
    data = None
    class_attr = None
    priori = {}
    cp = {}
    hypothesis = None


    def __init__(self,filename=None, class_attr=None ):
        self.data = pd.read_csv(filename, sep=',', header =(0))
        self.class_attr = class_attr

    '''
        probability(class) =    How many  times it appears in cloumn
                             __________________________________________
                                  count of all class attribute
    '''
    def calculate_priori(self):
        class_values = list(set(self.data[self.class_attr]))
        class_data =  list(self.data[self.class_attr])
        for i in class_values:
            self.priori[i]  = class_data.count(i)/float(len(class_data))
        print "Priori Values: ", self.priori

    '''
        Here we calculate the individual probabilites 
        P(outcome|evidence) =   P(Likelihood of Evidence) x Prior prob of outcome
                               ___________________________________________
                                                    P(Evidence)
    '''
    def get_cp(self, attr, attr_type, class_value):
        data_attr = list(self.data[attr])
        class_data = list(self.data[self.class_attr])
        total =1
        for i in range(0, len(data_attr)):
            if class_data[i] == class_value and data_attr[i] == attr_type:
                total+=1
        return total/float(class_data.count(class_value))

    '''
        Here we calculate Likelihood of Evidence and multiple all individual probabilities with priori
        (Outcome|Multiple Evidence) = P(Evidence1|Outcome) x P(Evidence2|outcome) x ... x P(EvidenceN|outcome) x P(Outcome)
        scaled by P(Multiple Evidence)
    '''
    def calculate_conditional_probabilities(self, hypothesis):
        for i in self.priori:
            self.cp[i] = {}
            for j in hypothesis:
                self.cp[i].update({ hypothesis[j]: self.get_cp(j, hypothesis[j], i)})
        print "\nCalculated Conditional Probabilities: \n"
        pprint.pprint(self.cp)

    def classify(self):
        print "Result: "
        for i in self.cp:
            print i, " ==> ", reduce(lambda x, y: x*y, self.cp[i].values())*self.priori[i]

if __name__ == "__main__":
    c = Classifier(filename="new_dataset.csv", class_attr="Buys_Computer" )
    c.calculate_priori()
    c.hypothesis = {"Age":'<=30', "Income":"medium", "Student":'yes' , "Creadit_Rating":'fair'}

    c.calculate_conditional_probabilities(c.hypothesis)
    c.classify()

output:

Priori Values:  {'yes': 0.6428571428571429, 'no': 0.35714285714285715}

Calculated Conditional Probabilities: 

{
 'no': {
        '<=30': 0.8,
        'fair': 0.6, 
        'medium': 0.6, 
        'yes': 0.4
        },
'yes': {
        '<=30': 0.3333333333333333,
        'fair': 0.7777777777777778,
        'medium': 0.5555555555555556,
        'yes': 0.7777777777777778
      }
}

Result: 
yes  ==>  0.0720164609053
no  ==>  0.0411428571429

Hope it helps in better understanding the problem

peace

Print all day-dates between two dates

I came up with this:

from datetime import date, timedelta

sdate = date(2008, 8, 15)   # start date
edate = date(2008, 9, 15)   # end date

delta = edate - sdate       # as timedelta

for i in range(delta.days + 1):
    day = sdate + timedelta(days=i)
    print(day)

The output:

2008-08-15
2008-08-16
...
2008-09-13
2008-09-14
2008-09-15

Your question asks for dates in-between but I believe you meant including the start and end points, so they are included. To remove the end date, delete the "+ 1" at the end of the range function. To remove the start date, insert a 1 argument to the beginning of the range function.

Server cannot set status after HTTP headers have been sent IIS7.5

Just to add to the responses above. I had this same issue when i first started using ASP.Net MVC and i was doing a Response.Redirect during a controller action:

Response.Redirect("/blah", true);

Instead of returning a Response.Redirect action i should have been returning a RedirectAction:

return Redirect("/blah");

subsetting a Python DataFrame

I've found that you can use any subset condition for a given column by wrapping it in []. For instance, you have a df with columns ['Product','Time', 'Year', 'Color']

And let's say you want to include products made before 2014. You could write,

df[df['Year'] < 2014]

To return all the rows where this is the case. You can add different conditions.

df[df['Year'] < 2014][df['Color' == 'Red']

Then just choose the columns you want as directed above. For instance, the product color and key for the df above,

df[df['Year'] < 2014][df['Color'] == 'Red'][['Product','Color']]

How to scroll to the bottom of a RecyclerView? scrollToPosition doesn't work

First time scroll when entering in recycler view first time then use

linearLayoutManager.scrollToPositionWithOffset(messageHashMap.size()-1

put in minus for scroll down for scroll up put in positive value);

if the view is very big in height then scrolltoposition particular offset is used for the top of view then you use

int overallXScroldl =chatMessageBinding.rvChat.computeVerticalScrollOffset();
chatMessageBinding.rvChat.smoothScrollBy(0, Math.abs(overallXScroldl));

Output single character in C

As mentioned in one of the other answers, you can use putc(int c, FILE *stream), putchar(int c) or fputc(int c, FILE *stream) for this purpose.

What's important to note is that using any of the above functions is from some to signicantly faster than using any of the format-parsing functions like printf.

Using printf is like using a machine gun to fire one bullet.

How to clear the entire array?

Only use Redim statement

 Dim aFirstArray() As Variant

Redim aFirstArray(nRows,nColumns)

Calling an executable program using awk

I was able to have this done via below method

cat ../logs/em2.log.1 |grep -i 192.168.21.15 |awk '{system(`date`); print $1}'

awk has a function called system it enables you to execute any linux bash command within the output of awk.

Inserting values to SQLite table in Android

I see it is an old thread but I had the same error.

I found the explanation here: http://developer.android.com/reference/android/database/sqlite/SQLiteDatabase.html

void execSQL(String sql)
Execute a single SQL statement that is NOT a SELECT or any other SQL statement that returns data.

void execSQL(String sql, Object[] bindArgs)
Execute a single SQL statement that is NOT a SELECT/INSERT/UPDATE/DELETE.

batch script - read line by line

Try this:

@echo off
for /f "tokens=*" %%a in (input.txt) do (
  echo line=%%a
)
pause

because of the tokens=* everything is captured into %a

edit: to reply to your comment, you would have to do that this way:

@echo off
for /f "tokens=*" %%a in (input.txt) do call :processline %%a

pause
goto :eof

:processline
echo line=%*

goto :eof

:eof

Because of the spaces, you can't use %1, because that would only contain the part until the first space. And because the line contains quotes, you can also not use :processline "%%a" in combination with %~1. So you need to use %* which gets %1 %2 %3 ..., so the whole line.

Warning: The method assertEquals from the type Assert is deprecated

You're using junit.framework.Assert instead of org.junit.Assert.

Why both no-cache and no-store should be used in HTTP response?

no-store should not be necessary in normal situations, and can harm both speed and usability. It is intended for use where the HTTP response contains information so sensitive it should never be written to a disk cache at all, regardless of the negative effects that creates for the user.

How it works:

  • Normally, even if a user agent such as a browser determines that a response shouldn't be cached, it may still store it to the disk cache for reasons internal to the user agent. This version may be utilised for features like "view source", "back", "page info", and so on, where the user hasn't necessarily requested the page again, but the browser doesn't consider it a new page view and it would make sense to serve the same version the user is currently viewing.

  • Using no-store will prevent that response being stored, but this may impact the browser's ability to give "view source", "back", "page info" and so on without making a new, separate request for the server, which is undesirable. In other words, the user may try viewing the source and if the browser didn't keep it in memory, they'll either be told this isn't possible, or it will cause a new request to the server. Therefore, no-store should only be used when the impeded user experience of these features not working properly or quickly is outweighed by the importance of ensuring content is not stored in the cache.

My current understanding is that it is just for intermediate cache server. Even if "no-cache" is in response, intermediate cache server can still save the content to non-volatile storage.

This is incorrect. Intermediate cache servers compatible with HTTP 1.1 will obey the no-cache and must-revalidate instructions, ensuring that content is not cached. Using these instructions will ensure that the response is not cached by any intermediate cache, and that all subsequent requests are sent back to the origin server.

If the intermediate cache server does not support HTTP 1.1, then you will need to use Pragma: no-cache and hope for the best. Note that if it doesn't support HTTP 1.1 then no-store is irrelevant anyway.

How to use nan and inf in C?

A compiler independent way, but not processor independent way to get these:

int inf = 0x7F800000;
return *(float*)&inf;

int nan = 0x7F800001;
return *(float*)&nan;

This should work on any processor which uses the IEEE 754 floating point format (which x86 does).

UPDATE: Tested and updated.

String Concatenation using '+' operator

It doesn't - the C# compiler does :)

So this code:

string x = "hello";
string y = "there";
string z = "chaps";
string all = x + y + z;

actually gets compiled as:

string x = "hello";
string y = "there";
string z = "chaps";
string all = string.Concat(x, y, z);

(Gah - intervening edit removed other bits accidentally.)

The benefit of the C# compiler noticing that there are multiple string concatenations here is that you don't end up creating an intermediate string of x + y which then needs to be copied again as part of the concatenation of (x + y) and z. Instead, we get it all done in one go.

EDIT: Note that the compiler can't do anything if you concatenate in a loop. For example, this code:

string x = "";
foreach (string y in strings)
{
    x += y;
}

just ends up as equivalent to:

string x = "";
foreach (string y in strings)
{
    x = string.Concat(x, y);
}

... so this does generate a lot of garbage, and it's why you should use a StringBuilder for such cases. I have an article going into more details about the two which will hopefully answer further questions.

What does mscorlib stand for?

Microsoft Core Library, ie they are at the heart of everything.

There is a more "massaged" explanation you may prefer:

"When Microsoft first started working on the .NET Framework, MSCorLib.dll was an acronym for Microsoft Common Object Runtime Library. Once ECMA started to standardize the CLR and parts of the FCL, MSCorLib.dll officially became the acronym for Multilanguage Standard Common Object Runtime Library."

From http://weblogs.asp.net/mreynolds/archive/2004/01/31/65551.aspx

Around 1999, to my personal memory, .Net was known as "COOL", so I am a little suspicious of this derivation. I never heard it called "COR", which is a silly-sounding name to a native English speaker.

Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?

There is no rule. I find CTEs more readable, and use them unless they exhibit some performance problem, in which case I investigate the actual problem rather than guess that the CTE is the problem and try to re-write it using a different approach. There is usually more to the issue than the way I chose to declaratively state my intentions with the query.

There are certainly cases when you can unravel CTEs or remove subqueries and replace them with a #temp table and reduce duration. This can be due to various things, such as stale stats, the inability to even get accurate stats (e.g. joining to a table-valued function), parallelism, or even the inability to generate an optimal plan because of the complexity of the query (in which case breaking it up may give the optimizer a fighting chance). But there are also cases where the I/O involved with creating a #temp table can outweigh the other performance aspects that may make a particular plan shape using a CTE less attractive.

Quite honestly, there are way too many variables to provide a "correct" answer to your question. There is no predictable way to know when a query may tip in favor of one approach or another - just know that, in theory, the same semantics for a CTE or a single subquery should execute the exact same. I think your question would be more valuable if you present some cases where this is not true - it may be that you have discovered a limitation in the optimizer (or discovered a known one), or it may be that your queries are not semantically equivalent or that one contains an element that thwarts optimization.

So I would suggest writing the query in a way that seems most natural to you, and only deviate when you discover an actual performance problem the optimizer is having. Personally I rank them CTE, then subquery, with #temp table being a last resort.

Scanner doesn't read whole sentence - difference between next() and nextLine() of scanner class

Default delimiter of Scanner is whitespace. Check javadoc for how to change this.

Hidden Features of C#?

TryParse method for each primitive type is great when validating user input.

double doubleValue
if (!Double.TryParse(myDataRow("myColumn"), out doubleValue))
{
    // set validation error
}

Is it possible to run CUDA on AMD GPUs?

I think it is going to be possible soon in AMD FirePro GPU's, see press release here but support is coming 2016 Q1 for the developing tools:

An early access program for the "Boltzmann Initiative" tools is planned for Q1 2016.

Using Application context everywhere?

Application Class:

import android.app.Application;
import android.content.Context;

public class MyApplication extends Application {

    private static Context mContext;

    public void onCreate() {
        super.onCreate();
        mContext = getApplicationContext();
    }

    public static Context getAppContext() {
        return mContext;
    }

}

Declare the Application in the AndroidManifest:

<application android:name=".MyApplication"
    ...
/>

Usage:

MyApplication.getAppContext()

Restart node upon changing a file

You should look at something like nodemon.

Nodemon will watch the files in the directory in which nodemon was started, and if they change, it will automatically restart your node application.

Example:

nodemon ./server.js localhost 8080

or simply

nodemon server

Using <style> tags in the <body> with other HTML

As others have said, this isn't valid html as the style tags belong in the head.

However, most browsers dont' really enforce that validation. Instead, once the document is loaded then the styles are merged and applied. In this case the second set of styles will always override the first because they were the last definitions encountered.

Calculating a 2D Vector's Cross Product

I'm using 2d cross product in my calculation to find the new correct rotation for an object that is being acted on by a force vector at an arbitrary point relative to its center of mass. (The scalar Z one.)

Passing capturing lambda as function pointer

While the template approach is clever for various reasons, it is important to remember the lifecycle of the lambda and the captured variables. If any form of a lambda pointer is is going to be used and the lambda is not a downward continuation, then only a copying [=] lambda should used. I.e., even then, capturing a pointer to a variable on the stack is UNSAFE if the lifetime of those captured pointers (stack unwind) is shorter than the lifetime of the lambda.

A simpler solution for capturing a lambda as a pointer is:

auto pLamdba = new std::function<...fn-sig...>([=](...fn-sig...){...});

e.g., new std::function<void()>([=]() -> void {...}

Just remember to later delete pLamdba so ensure that you don't leak the lambda memory. Secret to realize here is that lambdas can capture lambdas (ask yourself how that works) and also that in order for std::function to work generically the lambda implementation needs to contain sufficient internal information to provide access to the size of the lambda (and captured) data (which is why the delete should work [running destructors of captured types]).

Create Word Document using PHP in Linux

PHPWord can generate Word documents in docx format. It can also use an existing .docx file as a template - template variables can be added to the document in the format ${varname}

It has an LGPL license and the examples that came with the code worked nicely for me.

How are parameters sent in an HTTP POST request?

You cannot type it directly on the browser URL bar.

You can see how POST data is sent on the Internet with Live HTTP Headers for example. Result will be something like that

http://127.0.0.1/pass.php
POST /pass.php HTTP/1.1

Host: 127.0.0.1
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:18.0) Gecko/20100101 Firefox/18.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
DNT: 1
Referer: http://127.0.0.1/pass.php
Cookie: passx=87e8af376bc9d9bfec2c7c0193e6af70; PHPSESSID=l9hk7mfh0ppqecg8gialak6gt5
Connection: keep-alive
Content-Type: application/x-www-form-urlencoded
Content-Length: 30
username=zurfyx&pass=password

Where it says

Content-Length: 30
    username=zurfyx&pass=password

will be the post values.

How can I invert color using CSS?

Here is a different approach using mix-blend-mode: difference, that will actually invert whatever the background is, not just a single colour:

_x000D_
_x000D_
div {_x000D_
  background-image: linear-gradient(to right, red, yellow, green, cyan, blue, violet);_x000D_
}_x000D_
p {_x000D_
  color: white;_x000D_
  mix-blend-mode: difference;_x000D_
}
_x000D_
<div>_x000D_
  <p>Lorem ipsum dolor sit amet, consectetur adipiscit elit, sed do</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to remove all of the data in a table using Django

If you want to remove all the data from all your tables, you might want to try the command python manage.py flush. This will delete all of the data in your tables, but the tables themselves will still exist.

See more here: https://docs.djangoproject.com/en/1.8/ref/django-admin/

Best way to find os name and version in Unix/Linux platform

In every distribute it has difference files so I write most common ones:

---- CentOS Linux distro
`cat /proc/version`
---- Debian Linux distro
`cat /etc/debian_version`
---- Redhat Linux distro
`cat /etc/redhat-release` 
---- Ubuntu Linux distro
`cat /etc/issue`   or   `cat /etc/lsb-release`

in last one /etc/issue didn't exist so I tried the second one and it returned the right answer

Why can't I use a list as a dict key in python?

dict keys need to be hashable. Lists are Mutable and they do not provide a valid hash method.

Shell script variable not empty (-z option)

Why would you use -z? To test if a string is non-empty, you typically use -n:

if test -n "$errorstatus"; then
  echo errorstatus is not empty
fi

How do I round to the nearest 0.5?

Sounds like you need to round to the nearest 0.5. I see no version of round in the C# API that does this (one version takes a number of decimal digits to round to, which isn't the same thing).

Assuming you only have to deal with integer numbers of tenths, it's sufficient to calculate round (num * 2) / 2. If you're using arbitrarily precise decimals, it gets trickier. Let's hope you don't.

Get the IP address of the machine

I found the ioctl solution problematic on os x (which is POSIX compliant so should be similiar to linux). However getifaddress() will let you do the same thing easily, it works fine for me on os x 10.5 and should be the same below.

I've done a quick example below which will print all of the machine's IPv4 address, (you should also check the getifaddrs was successful ie returns 0).

I've updated it show IPv6 addresses too.

#include <stdio.h>      
#include <sys/types.h>
#include <ifaddrs.h>
#include <netinet/in.h> 
#include <string.h> 
#include <arpa/inet.h>

int main (int argc, const char * argv[]) {
    struct ifaddrs * ifAddrStruct=NULL;
    struct ifaddrs * ifa=NULL;
    void * tmpAddrPtr=NULL;

    getifaddrs(&ifAddrStruct);

    for (ifa = ifAddrStruct; ifa != NULL; ifa = ifa->ifa_next) {
        if (!ifa->ifa_addr) {
            continue;
        }
        if (ifa->ifa_addr->sa_family == AF_INET) { // check it is IP4
            // is a valid IP4 Address
            tmpAddrPtr=&((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
            char addressBuffer[INET_ADDRSTRLEN];
            inet_ntop(AF_INET, tmpAddrPtr, addressBuffer, INET_ADDRSTRLEN);
            printf("%s IP Address %s\n", ifa->ifa_name, addressBuffer); 
        } else if (ifa->ifa_addr->sa_family == AF_INET6) { // check it is IP6
            // is a valid IP6 Address
            tmpAddrPtr=&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
            char addressBuffer[INET6_ADDRSTRLEN];
            inet_ntop(AF_INET6, tmpAddrPtr, addressBuffer, INET6_ADDRSTRLEN);
            printf("%s IP Address %s\n", ifa->ifa_name, addressBuffer); 
        } 
    }
    if (ifAddrStruct!=NULL) freeifaddrs(ifAddrStruct);
    return 0;
}

Spring Boot yaml configuration for a list of strings

Well, the only thing I can make it work is like so:

servers: >
    dev.example.com,
    another.example.com

@Value("${servers}")
private String[] array;

And dont forget the @Configuration above your class....

Without the "," separation, no such luck...

Works too (boot 1.5.8 versie)

servers: 
       dev.example.com,
       another.example.com

How to read/write arbitrary bits in C/C++

You have to do a shift and mask (AND) operation. Let b be any byte and p be the index (>= 0) of the bit from which you want to take n bits (>= 1).

First you have to shift right b by p times:

x = b >> p;

Second you have to mask the result with n ones:

mask = (1 << n) - 1;
y = x & mask;

You can put everything in a macro:

#define TAKE_N_BITS_FROM(b, p, n) ((b) >> (p)) & ((1 << (n)) - 1)

Access POST values in Symfony2 request object

If you are newbie, welcome to Symfony2, an open-source project so if you want to learn a lot, you can open the source !

From "Form.php" :

getData() getNormData() getViewData()

You can find more details in this file.

Multiline text in JLabel

You can use JTextArea and remove editing capabilities to get normal read-only multiline text.

JTextArea textArea = new JTextArea("line\nline\nline");
textArea.setEditable(false);

JTextArea

setEditable

How to download a file from a URL in C#?

Check for a network connection using GetIsNetworkAvailable() to avoid creating empty files when not connected to a network.

if (System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable())
{
    using (System.Net.WebClient client = new System.Net.WebClient())
    {                        
          client.DownloadFileAsync(new Uri("http://www.examplesite.com/test.txt"),
          "D:\\test.txt");
    }                  
}

Replace all elements of Python NumPy Array that are greater than some value

You can consider using numpy.putmask:

np.putmask(arr, arr>=T, 255.0)

Here is a performance comparison with the Numpy's builtin indexing:

In [1]: import numpy as np
In [2]: A = np.random.rand(500, 500)

In [3]: timeit np.putmask(A, A>0.5, 5)
1000 loops, best of 3: 1.34 ms per loop

In [4]: timeit A[A > 0.5] = 5
1000 loops, best of 3: 1.82 ms per loop

Converting string to integer

The function you need is CInt.

ie CInt(PrinterLabel)

See Type Conversion Functions (Visual Basic) on MSDN

Edit: Be aware that CInt and its relatives behave differently in VB.net and VBScript. For example, in VB.net, CInt casts to a 32-bit integer, but in VBScript, CInt casts to a 16-bit integer. Be on the lookout for potential overflows!

Create excel ranges using column numbers in vba?

Below are two solutions to select the range A1.

Cells(1,1).Select '(row 1, column 1) 
Range("A1").Select

Also check out this link;

We strongly recommend that you use Range instead of Cells to work with cells and groups of cells. It makes your sentences much clearer and you are not forced to remember that column AE is column 31.

The only time that you will use Cells is when you want to select all the cells of a worksheet. For example: Cells.Select To select all cells and then empty all cells of values or formulas you will use: Cells.ClearContents

--

"Cells" is particularly useful when setting ranges dynamically and looping through ranges by using counters. Defining ranges using letters as column numbers may be more transparent on the short run, but it will also make your application more rigid since they are "hard coded" representations - not dynamic.

Thanks to Kim Gysen

_DEBUG vs NDEBUG

I rely on NDEBUG, because it's the only one whose behavior is standardized across compilers and implementations (see documentation for the standard assert macro). The negative logic is a small readability speedbump, but it's a common idiom you can quickly adapt to.

To rely on something like _DEBUG would be to rely on an implementation detail of a particular compiler and library implementation. Other compilers may or may not choose the same convention.

The third option is to define your own macro for your project, which is quite reasonable. Having your own macro gives you portability across implementations and it allows you to enable or disable your debugging code independently of the assertions. Though, in general, I advise against having different classes of debugging information that are enabled at compile time, as it causes an increase in the number of configurations you have to build (and test) for arguably small benefit.

With any of these options, if you use third party code as part of your project, you'll have to be aware of which convention it uses.