Programs & Examples On #Osx server

OS X Server was a server operating system distributed by Apple Inc. which was architecturally identical to its desktop counterpart OS X, with additional functionality.

Socket File "/var/pgsql_socket/.s.PGSQL.5432" Missing In Mountain Lion (OS X Server)

I was able to add the following to my .bash_profile to prevent the error:

export PGHOST=localhost

This works because:

If you omit the host name, psql will connect via a Unix-domain socket to a server on the local host, or via TCP/IP to localhost on machines that don't have Unix-domain sockets.

Your OS supports Unix domain sockets, but PostgreSQL's Unix socket that psql needs either doesn't exist or is in a different location than it expects.

Specifying a hostname explicitly as localhost forces psql to use TCP/IP. Setting an environment variable PGHOST is one of the ways to achieve that. It's documented in psql's manual.

Call to undefined function App\Http\Controllers\ [ function name ]

say you define the static getFactorial function inside a CodeController

then this is the way you need to call a static function, because static properties and methods exists with in the class, not in the objects created using the class.

CodeController::getFactorial($index);

----------------UPDATE----------------

To best practice I think you can put this kind of functions inside a separate file so you can maintain with more easily.

to do that

create a folder inside app directory and name it as lib (you can put a name you like).

this folder to needs to be autoload to do that add app/lib to composer.json as below. and run the composer dumpautoload command.

"autoload": {
    "classmap": [
                "app/commands",
                "app/controllers",
                ............
                "app/lib"
    ]
},

then files inside lib will autoloaded.

then create a file inside lib, i name it helperFunctions.php

inside that define the function.

if ( ! function_exists('getFactorial'))
{

    /**
     * return the factorial of a number
     *
     * @param $number
     * @return string
     */
    function getFactorial($date)
    {
        $fact = 1;

        for($i = 1; $i <= $num ;$i++)
            $fact = $fact * $i;

        return $fact;

     }
}

and call it anywhere within the app as

$fatorial_value = getFactorial(225);

Twitter Bootstrap tabs not working: when I click on them nothing happens

For me, the problem was that I wasn't including bootstrap.min.css (I was only including bootstrap-responsive.min.css).

Does JavaScript have a built in stringbuilder class?

I just rechecked the performance on http://jsperf.com/javascript-concat-vs-join/2. The test-cases concatenate or join the alphabet 1,000 times.

In current browsers (FF, Opera, IE11, Chrome), "concat" is about 4-10 times faster than "join".

In IE8, both return about equal results.

In IE7, "join" is about 100 times faster unfortunately.

How can I run PowerShell with the .NET 4 runtime?

If you only need to execute a single command, script block, or script file in .NET 4, try using Activation Configuration Files from .NET 4 to start only a single instance of PowerShell using version 4 of the CLR.

Full details:

http://blog.codeassassin.com/2011/03/23/executing-individual-powershell-commands-using-net-4/

An example PowerShell module:

https://gist.github.com/882528

Ignore self-signed ssl cert using Jersey Client

worked for me with this code. May be its for Java 1.7

    TrustManager[] trustAllCerts = new TrustManager[]{new X509TrustManager() {

        @Override
        public X509Certificate[] getAcceptedIssuers() {
            // TODO Auto-generated method stub
            return null;
        }

        @Override
        public void checkServerTrusted(X509Certificate[] arg0, String arg1)
                throws CertificateException {
            // TODO Auto-generated method stub

        }

        @Override
        public void checkClientTrusted(X509Certificate[] arg0, String arg1)
                throws CertificateException {
            // TODO Auto-generated method stub

        }
    }};

    // Install the all-trusting trust manager
    try {
        SSLContext sc = SSLContext.getInstance("TLS");
        sc.init(null, trustAllCerts, new SecureRandom());
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
    } catch (Exception e) {
        ;
    }

Cannot uninstall angular-cli

You are using the beta version of angular CLI you can do this way.

npm uninstall -g @angular/cli
npm uninstall -g angular/cli

Then type,

npm cache clean

Then go to the AppData folder which is hidden in your users and go to roaming folder which is inside AppData then go to npm folder and delete angular files in there and also go to npm-cache folder and delete angular components in there.After that restart your PC and type

npm install -g @angular/cli@latest

This worked for me ??

HTTP Ajax Request via HTTPS Page

From the javascript I tried from several ways and I could not.

You need an server side solution, for example on c# I did create an controller that call to the http, en deserialize the object, and the result is that when I call from javascript, I'm doing an request from my https://domain to my htpps://domain. Please see my c# code:

[Authorize]
public class CurrencyServicesController : Controller
{
    HttpClient client;
    //GET: CurrencyServices/Consultar?url=valores?moedas=USD&alt=json
    public async Task<dynamic> Consultar(string url)
    {
        client = new HttpClient();
        client.BaseAddress = new Uri("http://api.promasters.net.br/cotacao/v1/");
        client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
        System.Net.Http.HttpResponseMessage response = client.GetAsync(url).Result;

        var FromURL = response.Content.ReadAsStringAsync().Result;

        return JsonConvert.DeserializeObject(FromURL);
    }

And let me show to you my client side (Javascript)

<script async>
$(document).ready(function (data) {

    var TheUrl = '@Url.Action("Consultar", "CurrencyServices")?url=valores';
    $.getJSON(TheUrl)
        .done(function (data) {
            $('#DolarQuotation').html(
                '$ ' + data.valores.USD.valor.toFixed(2) + ','
            );
            $('#EuroQuotation').html(
                '€ ' + data.valores.EUR.valor.toFixed(2) + ','
            );

            $('#ARGPesoQuotation').html(
                'Ar$ ' + data.valores.ARS.valor.toFixed(2) + ''
            );

        });       

});

I wish that this help you! Greetings

Can I assume (bool)true == (int)1 for any C++ compiler?

According to the standard, you should be safe with that assumption. The C++ bool type has two values - true and false with corresponding values 1 and 0.

The thing to watch about for is mixing bool expressions and variables with BOOL expression and variables. The latter is defined as FALSE = 0 and TRUE != FALSE, which quite often in practice means that any value different from 0 is considered TRUE.

A lot of modern compilers will actually issue a warning for any code that implicitly tries to cast from BOOL to bool if the BOOL value is different than 0 or 1.

Iteration ng-repeat only X times in AngularJs

This is the simplest workaround I could think of.

<span ng-repeat="n in [].constructor(5) track by $index">
{{$index}}
</span>

Here's a Plunker example.

Set font-weight using Bootstrap classes

In Bootstrap 4:

class="font-weight-bold"

Or:

<strong>text</strong>

Strange out of memory issue while loading an image to a Bitmap object

This seems like the appropriate place to share my utility class for loading and processing images with the community, you are welcome to use it and modify it freely.

package com.emil;

import java.io.IOException;
import java.io.InputStream;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

/**
 * A class to load and process images of various sizes from input streams and file paths.
 * 
 * @author Emil http://stackoverflow.com/users/220710/emil
 *
 */
public class ImageProcessing {

    public static Bitmap getBitmap(InputStream stream, int sampleSize, Bitmap.Config bitmapConfig) throws IOException{
        BitmapFactory.Options options=ImageProcessing.getOptionsForSampling(sampleSize, bitmapConfig);
        Bitmap bm = BitmapFactory.decodeStream(stream,null,options);
        if(ImageProcessing.checkDecode(options)){
            return bm;
        }else{
            throw new IOException("Image decoding failed, using stream.");
        }
    }

    public static Bitmap getBitmap(String imgPath, int sampleSize, Bitmap.Config bitmapConfig) throws IOException{
        BitmapFactory.Options options=ImageProcessing.getOptionsForSampling(sampleSize, bitmapConfig);
        Bitmap bm = BitmapFactory.decodeFile(imgPath,options);
        if(ImageProcessing.checkDecode(options)){
            return bm;
        }else{
            throw new IOException("Image decoding failed, using file path.");
        }
    }

    public static Dimensions getDimensions(InputStream stream) throws IOException{
        BitmapFactory.Options options=ImageProcessing.getOptionsForDimensions();
        BitmapFactory.decodeStream(stream,null,options);
        if(ImageProcessing.checkDecode(options)){
            return new ImageProcessing.Dimensions(options.outWidth,options.outHeight);
        }else{
            throw new IOException("Image decoding failed, using stream.");
        }
    }

    public static Dimensions getDimensions(String imgPath) throws IOException{
        BitmapFactory.Options options=ImageProcessing.getOptionsForDimensions();
        BitmapFactory.decodeFile(imgPath,options);
        if(ImageProcessing.checkDecode(options)){
            return new ImageProcessing.Dimensions(options.outWidth,options.outHeight);
        }else{
            throw new IOException("Image decoding failed, using file path.");
        }
    }

    private static boolean checkDecode(BitmapFactory.Options options){
        // Did decode work?
        if( options.outWidth<0 || options.outHeight<0 ){
            return false;
        }else{
            return true;
        }
    }

    /**
     * Creates a Bitmap that is of the minimum dimensions necessary
     * @param bm
     * @param min
     * @return
     */
    public static Bitmap createMinimalBitmap(Bitmap bm, ImageProcessing.Minimize min){
        int newWidth, newHeight;
        switch(min.type){
        case WIDTH:
            if(bm.getWidth()>min.minWidth){
                newWidth=min.minWidth;
                newHeight=ImageProcessing.getScaledHeight(newWidth, bm);
            }else{
                // No resize
                newWidth=bm.getWidth();
                newHeight=bm.getHeight();
            }
            break;
        case HEIGHT:
            if(bm.getHeight()>min.minHeight){
                newHeight=min.minHeight;
                newWidth=ImageProcessing.getScaledWidth(newHeight, bm);
            }else{
                // No resize
                newWidth=bm.getWidth();
                newHeight=bm.getHeight();
            }
            break;
        case BOTH: // minimize to the maximum dimension
        case MAX:
            if(bm.getHeight()>bm.getWidth()){
                // Height needs to minimized
                min.minDim=min.minDim!=null ? min.minDim : min.minHeight;
                if(bm.getHeight()>min.minDim){
                    newHeight=min.minDim;
                    newWidth=ImageProcessing.getScaledWidth(newHeight, bm);
                }else{
                    // No resize
                    newWidth=bm.getWidth();
                    newHeight=bm.getHeight();
                }
            }else{
                // Width needs to be minimized
                min.minDim=min.minDim!=null ? min.minDim : min.minWidth;
                if(bm.getWidth()>min.minDim){
                    newWidth=min.minDim;
                    newHeight=ImageProcessing.getScaledHeight(newWidth, bm);
                }else{
                    // No resize
                    newWidth=bm.getWidth();
                    newHeight=bm.getHeight();
                }
            }
            break;
        default:
            // No resize
            newWidth=bm.getWidth();
            newHeight=bm.getHeight();
        }
        return Bitmap.createScaledBitmap(bm, newWidth, newHeight, true);
    }

    public static int getScaledWidth(int height, Bitmap bm){
        return (int)(((double)bm.getWidth()/bm.getHeight())*height);
    }

    public static int getScaledHeight(int width, Bitmap bm){
        return (int)(((double)bm.getHeight()/bm.getWidth())*width);
    }

    /**
     * Get the proper sample size to meet minimization restraints
     * @param dim
     * @param min
     * @param multipleOf2 for fastest processing it is recommended that the sample size be a multiple of 2
     * @return
     */
    public static int getSampleSize(ImageProcessing.Dimensions dim, ImageProcessing.Minimize min, boolean multipleOf2){
        switch(min.type){
        case WIDTH:
            return ImageProcessing.getMaxSampleSize(dim.width, min.minWidth, multipleOf2);
        case HEIGHT:
            return ImageProcessing.getMaxSampleSize(dim.height, min.minHeight, multipleOf2);
        case BOTH:
            int widthMaxSampleSize=ImageProcessing.getMaxSampleSize(dim.width, min.minWidth, multipleOf2);
            int heightMaxSampleSize=ImageProcessing.getMaxSampleSize(dim.height, min.minHeight, multipleOf2);
            // Return the smaller of the two
            if(widthMaxSampleSize<heightMaxSampleSize){
                return widthMaxSampleSize;
            }else{
                return heightMaxSampleSize;
            }
        case MAX:
            // Find the larger dimension and go bases on that
            if(dim.width>dim.height){
                return ImageProcessing.getMaxSampleSize(dim.width, min.minDim, multipleOf2);
            }else{
                return ImageProcessing.getMaxSampleSize(dim.height, min.minDim, multipleOf2);
            }
        }
        return 1;
    }

    public static int getMaxSampleSize(int dim, int min, boolean multipleOf2){
        int add=multipleOf2 ? 2 : 1;
        int size=0;
        while(min<(dim/(size+add))){
            size+=add;
        }
        size = size==0 ? 1 : size;
        return size;        
    }

    public static class Dimensions {
        int width;
        int height;

        public Dimensions(int width, int height) {
            super();
            this.width = width;
            this.height = height;
        }

        @Override
        public String toString() {
            return width+" x "+height;
        }
    }

    public static class Minimize {
        public enum Type {
            WIDTH,HEIGHT,BOTH,MAX
        }
        Integer minWidth;
        Integer minHeight;
        Integer minDim;
        Type type;

        public Minimize(int min, Type type) {
            super();
            this.type = type;
            switch(type){
            case WIDTH:
                this.minWidth=min;
                break;
            case HEIGHT:
                this.minHeight=min;
                break;
            case BOTH:
                this.minWidth=min;
                this.minHeight=min;
                break;
            case MAX:
                this.minDim=min;
                break;
            }
        }

        public Minimize(int minWidth, int minHeight) {
            super();
            this.type=Type.BOTH;
            this.minWidth = minWidth;
            this.minHeight = minHeight;
        }

    }

    /**
     * Estimates size of Bitmap in bytes depending on dimensions and Bitmap.Config
     * @param width
     * @param height
     * @param config
     * @return
     */
    public static long estimateBitmapBytes(int width, int height, Bitmap.Config config){
        long pixels=width*height;
        switch(config){
        case ALPHA_8: // 1 byte per pixel
            return pixels;
        case ARGB_4444: // 2 bytes per pixel, but depreciated
            return pixels*2;
        case ARGB_8888: // 4 bytes per pixel
            return pixels*4;
        case RGB_565: // 2 bytes per pixel
            return pixels*2;
        default:
            return pixels;
        }
    }

    private static BitmapFactory.Options getOptionsForDimensions(){
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds=true;
        return options;
    }

    private static BitmapFactory.Options getOptionsForSampling(int sampleSize, Bitmap.Config bitmapConfig){
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = false;
        options.inDither = false;
        options.inSampleSize = sampleSize;
        options.inScaled = false;
        options.inPreferredConfig = bitmapConfig;
        return options;
    }
}

Access denied for root user in MySQL command-line

Are you logging into MySQL as root? You have to explicitly grant privileges to your "regular" MySQL user account while logged in as MySQL root.

First set up a root account for your MySQL database.

In the terminal type:

mysqladmin -u root password 'password'

To log into MySQL, use this:

mysql -u root -p

To set the privileges manually start the server with the skip-grant-tables option, open mysql client and manually update the mysql.user table and/or the mysql.db tables. This can be a tedious task though so if what you need is an account with all privs I would do the following.

Start the server with the skip-grant-tables option

Start mysql client (without a username/password)

Issue the command

flush privileges;

which forces the grant tables to be loaded.

Create a new account with the GRANT command something like this (but replacing username and password with whatever you want to use.

GRANT ALL on *.* to 'username'@'localhost' identified by 'password';

Restart the server in normal mode (without skip-grant-tables) and log in with your newly created account.

Refer this MySQL docs.

Datatables: Cannot read property 'mData' of undefined

Having <thead> and <tbody> with the same numbers of <th> and <td> solved my problem.

What is EOF in the C programming language?

to keep it simple: EOF is an integer type with value -1. Therefore, we must use an integer variable to test EOF.

C# loop - break vs. continue

Break

Break forces a loop to exit immediately.

Continue

This does the opposite of break. Instead of terminating the loop, it immediately loops again, skipping the rest of the code.

How to suppress "error TS2533: Object is possibly 'null' or 'undefined'"?

Try to call object like this:

(<any>Object).dosomething

This error has come because you have declared them as optional using ?. Now Typescript does strict check and it won't allow doing anything that may be undefined. Therefore, you can use (<any>yourObject) here.

Disable spell-checking on HTML textfields

Update: As suggested by a commenter (additional credit to How can I disable the spell checker on text inputs on the iPhone), use this to handle all desktop and mobile browsers.

<tag autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"/>

Original answer: Javascript cannot override user settings, so unless you use another mechanism other than textfields, this is not (or shouldn't be) possible.

await vs Task.Wait - Deadlock?

Wait and await - while similar conceptually - are actually completely different.

Wait will synchronously block until the task completes. So the current thread is literally blocked waiting for the task to complete. As a general rule, you should use "async all the way down"; that is, don't block on async code. On my blog, I go into the details of how blocking in asynchronous code causes deadlock.

await will asynchronously wait until the task completes. This means the current method is "paused" (its state is captured) and the method returns an incomplete task to its caller. Later, when the await expression completes, the remainder of the method is scheduled as a continuation.

You also mentioned a "cooperative block", by which I assume you mean a task that you're Waiting on may execute on the waiting thread. There are situations where this can happen, but it's an optimization. There are many situations where it can't happen, like if the task is for another scheduler, or if it's already started or if it's a non-code task (such as in your code example: Wait cannot execute the Delay task inline because there's no code for it).

You may find my async / await intro helpful.

java: HashMap<String, int> not working

You cannot use primitive types in HashMap. int, or double don't work. You have to use its enclosing type. for an example

Map<String,Integer> m = new HashMap<String,Integer>();

Now both are objects, so this will work.

How to process SIGTERM signal gracefully?

I think you are near to a possible solution.

Execute mainloop in a separate thread and extend it with the property shutdown_flag. The signal can be caught with signal.signal(signal.SIGTERM, handler) in the main thread (not in a separate thread). The signal handler should set shutdown_flag to True and wait for the thread to end with thread.join()

MySQL: Error Code: 1118 Row size too large (> 8126). Changing some columns to TEXT or BLOB

ERROR 1118 (42000) at line 1852:    
Row size too large (> 8126). Changing some columns to TEXT or 
     BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.

[mysqld]

innodb_log_file_size = 512M

innodb_strict_mode = 0

ubuntu 16.04 edit path:

sudo nano /etc/mysql/mysql.conf.d/mysqld.cnf

on MS Windows the path will be something like:

C:\ProgramData\MySQL\MySQL Server 5.7\my.ini

Don't forget to retart the service (or restart your machine)

Autocomplete syntax for HTML or PHP in Notepad++. Not auto-close, autocompelete

In Notepad++ v. 6.4.1 is this possibility in:Settings->Preferences->Auto-Completion and there check Enable auto-completion on each input.

For auto-complete in code press Ctrl + Enter.

Undefined symbols for architecture arm64

In my case, I had to look for

C++ Standard Library and make sure that the libc++ was the one selected.

Portable way to get file size (in bytes) in shell?

Even though du usually prints disk usage and not actual data size, GNU coreutils du can print file's "apparent size" in bytes:

du -b FILE

But it won't work under BSD, Solaris, macOS, ...

jquery animate background position

jQuery's animate function is not exclusively usable for directly animating properties of DOM-objects. You can also tween variables and use the step function to get the variables for every step of the tween.

For example, to animate a background-position from background-position(0px 0px) to background-position(100px 500px) you can do this:

$({temporary_x: 0, temporary_y: 0}).animate({temporary_x: 100, temporary_y: 500}, {
    duration: 1000,
    step: function() {
        var position = Math.round(this.temporary_x) + "px " + Math.round(this.temporary_y) + "px";
        $("#your_div").css("background-position",  position);
    }
});

Just make sure to not forget the this. inside the step function.

Spark DataFrame TimestampType - how to get Year, Month, Day values from field?

Actually, we really do not need to import any python library. We can separate the year, month, date using simple SQL. See the below example,

+----------+
|       _c0|
+----------+
|1872-11-30|
|1873-03-08|
|1874-03-07|
|1875-03-06|
|1876-03-04|
|1876-03-25|
|1877-03-03|
|1877-03-05|
|1878-03-02|
|1878-03-23|
|1879-01-18|

I have a date column in my data frame which contains the date, month and year and assume I want to extract only the year from the column.

df.createOrReplaceTempView("res")
sqlDF = spark.sql("SELECT EXTRACT(year from `_c0`) FROM res ")

Here I'm creating a temporary view and store the year values using this single line and the output will be,

+-----------------------+
|year(CAST(_c0 AS DATE))|
+-----------------------+
|                   1872|
|                   1873|
|                   1874|
|                   1875|
|                   1876|
|                   1876|
|                   1877|
|                   1877|
|                   1878|
|                   1878|
|                   1879|
|                   1879|
|                   1879|

Use jQuery to change a second select list based on the first select list option

Store all #select2's options in a variable, filter them according to the value of the chosen option in #select1, and set them using .html() in #select2:

var $select1 = $( '#select1' ),
    $select2 = $( '#select2' ),
    $options = $select2.find( 'option' );

$select1.on('change', function() {
    $select2.html($options.filter('[value="' + this.value + '"]'));
}).trigger('change'); 

Here's a fiddle

How to call a method after bean initialization is complete?

You could deploy a custom BeanPostProcessor in your application context to do it. Or if you don't mind implementing a Spring interface in your bean, you could use the InitializingBean interface or the "init-method" directive (same link).

What happened to Lodash _.pluck?

There isn't a need for _.map or _.pluck since ES6 has taken off.

Here's an alternative using ES6 JavaScript:

clips.map(clip => clip.id)

Swapping pointers in C (char, int)

This example does not swap two int pointers. It swaps the value of the integers that pa and pb are pointing to. Here's an example of what's going on when you call this:

void Swap1 (int *pa, int *pb){
    int temp = *pa;
    *pa = *pb;
    *pb = temp;
}
int main()
{
    int a = 42;
    int b = 17;


    int *pa = &a;
    int *pb = &b;

    printf("--------Swap1---------\n");
    printf("a = %d\n b = %d\n", a, b);
    swap1(pa, pb);
    printf("a = %d\n = %d\n", a, a);
    printf("pb address =  %p\n", pa);
    printf("pa address =  %p\n", pb);
}

The output here is:

a = 42
b = 17
pa address =  0x7fffdf933228
pb address =  0x7fffdf93322c
--------Swap---------
pa = 17
pb = 42
a = 17
b = 42
pa address =  0x7fffdf933228
pb address =  0x7fffdf93322c

Note that the values swapped, but the pointer's addresses did not swap!

In order to swap addresses we need to do this:

void swap2 (int **pa, int **pb){
    int temp = *pa;
    *pa = *pb;
    *pb = temp;
}

and in main call the function like swap2(&pa, &pb);

Now the addresses are swapped, as well as the values for the pointers. a and b have the same values that the are initialized with The integers a and b did not swap because it swap2 swaps the addresses being being pointed to by the pointers!:

a = 42
b = 17
pa address =  0x7fffddaa9c98
pb address =  0x7fffddaa9c9c
--------Swap---------
pa = 17
pb = 42
a = 42
b = 17
pa address =  0x7fffddaa9c9c
pb address =  0x7fffddaa9c98

Since Strings in C are char pointers, and you want to swap Strings, you are really swapping a char pointer. As in the examples with an int, you need a double pointer to swap addresses.

The values of integers can be swapped even if the address isn't, but Strings are by definition a character pointer. You could swap one char with single pointers as the parameter, but a character pointer needs to be a double pointer in order to swap the strings.

Math operations from string

You could use this function which is doing the same as the eval() function, but in a simple manner, using a function.

def numeric(equation):
    if '+' in equation:
        y = equation.split('+')
        x = int(y[0])+int(y[1])
    elif '-' in equation:
        y = equation.split('-')
        x = int(y[0])-int(y[1])
    return x

How to assign execute permission to a .sh file in windows to be executed in linux

This is not possible. Linux permissions and windows permissions do not translate. They are machine specific. It would be a security hole to allow permissions to be set on files before they even arrive on the target system.

Raise error in a Bash script

Basic error handling

If your test case runner returns a non-zero code for failed tests, you can simply write:

test_handler test_case_x; test_result=$?
if ((test_result != 0)); then
  printf '%s\n' "Test case x failed" >&2  # write error message to stderr
  exit 1                                  # or exit $test_result
fi

Or even shorter:

if ! test_handler test_case_x; then
  printf '%s\n' "Test case x failed" >&2
  exit 1
fi

Or the shortest:

test_handler test_case_x || { printf '%s\n' "Test case x failed" >&2; exit 1; }

To exit with test_handler's exit code:

test_handler test_case_x || { ec=$?; printf '%s\n' "Test case x failed" >&2; exit $ec; }

Advanced error handling

If you want to take a more comprehensive approach, you can have an error handler:

exit_if_error() {
  local exit_code=$1
  shift
  [[ $exit_code ]] &&               # do nothing if no error code passed
    ((exit_code != 0)) && {         # do nothing if error code is 0
      printf 'ERROR: %s\n' "$@" >&2 # we can use better logging here
      exit "$exit_code"             # we could also check to make sure
                                    # error code is numeric when passed
    }
}

then invoke it after running your test case:

run_test_case test_case_x
exit_if_error $? "Test case x failed"

or

run_test_case test_case_x || exit_if_error $? "Test case x failed"

The advantages of having an error handler like exit_if_error are:

  • we can standardize all the error handling logic such as logging, printing a stack trace, notification, doing cleanup etc., in one place
  • by making the error handler get the error code as an argument, we can spare the caller from the clutter of if blocks that test exit codes for errors
  • if we have a signal handler (using trap), we can invoke the error handler from there

Error handling and logging library

Here is a complete implementation of error handling and logging:

https://github.com/codeforester/base/blob/master/lib/stdlib.sh


Related posts

Angular ng-repeat add bootstrap row every 3 or 4 cols

You can do it without a directive but i'm not sure it's the best way. To do this you must create array of array from the data you want to display in the table, and after that use 2 ng-repeat to iterate through the array.

to create the array for display use this function like that products.chunk(3)

Array.prototype.chunk = function(chunkSize) {
    var array=this;
    return [].concat.apply([],
        array.map(function(elem,i) {
            return i%chunkSize ? [] : [array.slice(i,i+chunkSize)];
        })
    );
}

and then do something like that using 2 ng-repeat

<div class="row" ng-repeat="row in products.chunk(3)">
  <div class="col-sm4" ng-repeat="item in row">
    {{item}}
  </div>
</div>

What ports does RabbitMQ use?

Port Access

Firewalls and other security tools may prevent RabbitMQ from binding to a port. When that happens, RabbitMQ will fail to start. Make sure the following ports can be opened:

4369: epmd, a peer discovery service used by RabbitMQ nodes and CLI tools

5672, 5671: used by AMQP 0-9-1 and 1.0 clients without and with TLS

25672: used by Erlang distribution for inter-node and CLI tools communication and is allocated from a dynamic range (limited to a single port by default, computed as AMQP port + 20000). See networking guide for details.

15672: HTTP API clients and rabbitmqadmin (only if the management plugin is enabled)

61613, 61614: STOMP clients without and with TLS (only if the STOMP plugin is enabled)

1883, 8883: (MQTT clients without and with TLS, if the MQTT plugin is enabled

15674: STOMP-over-WebSockets clients (only if the Web STOMP plugin is enabled)

15675: MQTT-over-WebSockets clients (only if the Web MQTT plugin is enabled)

Reference doc: https://www.rabbitmq.com/install-windows-manual.html

Set new id with jQuery

Did you try

$(this).val('test');

instead of

$(this).attr('value', 'test');

val() is generally easier, since the attribute you need to change may be different on different DOM elements.

Node.js - How to send data from html to express

Using http.createServer is very low-level and really not useful for creating web applications as-is.

A good framework to use on top of it is Express, and I would seriously suggest using it. You can install it using npm install express.

When you have, you can create a basic application to handle your form:

var express = require('express');
var bodyParser = require('body-parser');
var app     = express();

//Note that in version 4 of express, express.bodyParser() was
//deprecated in favor of a separate 'body-parser' module.
app.use(bodyParser.urlencoded({ extended: true })); 

//app.use(express.bodyParser());

app.post('/myaction', function(req, res) {
  res.send('You sent the name "' + req.body.name + '".');
});

app.listen(8080, function() {
  console.log('Server running at http://127.0.0.1:8080/');
});

You can make your form point to it using:

<form action="http://127.0.0.1:8080/myaction" method="post">

The reason you can't run Node on port 80 is because there's already a process running on that port (which is serving your index.html). You could use Express to also serve static content, like index.html, using the express.static middleware.

What is the difference between char array and char pointer in C?

char* and char[] are different types, but it's not immediately apparent in all cases. This is because arrays decay into pointers, meaning that if an expression of type char[] is provided where one of type char* is expected, the compiler automatically converts the array into a pointer to its first element.

Your example function printSomething expects a pointer, so if you try to pass an array to it like this:

char s[10] = "hello";
printSomething(s);

The compiler pretends that you wrote this:

char s[10] = "hello";
printSomething(&s[0]);

Programmatically select a row in JTable

You can do it calling setRowSelectionInterval :

table.setRowSelectionInterval(0, 0);

to select the first row.

Storing money in a decimal column - what precision and scale?

Sometimes you will need to go to less than a cent and there are international currencies that use very large demoniations. For example, you might charge your customers 0.088 cents per transaction. In my Oracle database the columns are defined as NUMBER(20,4)

What do 'lazy' and 'greedy' mean in the context of regular expressions?

Greedy means it will consume your pattern until there are none of them left and it can look no further.

Lazy will stop as soon as it will encounter the first pattern you requested.

One common example that I often encounter is \s*-\s*? of a regex ([0-9]{2}\s*-\s*?[0-9]{7})

The first \s* is classified as greedy because of * and will look as many white spaces as possible after the digits are encountered and then look for a dash character "-". Where as the second \s*? is lazy because of the present of *? which means that it will look the first white space character and stop right there.

Rounded corners for <input type='text' /> using border-radius.htc for IE

W3C doc says regarding "border-radius" property: "supported in IE9+, Firefox, Chrome, Safari, and Opera".

Hence I assume you're testing on IE8 or below.

For "regular elements" there is a solution compatible with IE8 & other old/poor browsers. See below.

HTML:

<div class="myWickedClass">
  <span class="myCoolItem">Some text</span> <span class="myCoolItem">Some text</span> <span class="myCoolItem"> Some text</span> <span class="myCoolItem">Some text</span>
</div>

CSS:

.myWickedClass{
  padding: 0 5px 0 0;
  background: #F7D358 url(../img/roundedCorner_right.png) top right no-repeat scroll;
  -moz-border-radius: 10px;
  -webkit-border-radius: 10px;
  border-radius: 10px;
  font: normal 11px Verdana, Helvetica, sans-serif;
  color: #A4A4A4;
}
.myWickedClass > .myCoolItem:first-child {
  padding-left: 6px;
  background: #F7D358 url(../img/roundedCorner_left.png) 0px 0px no-repeat scroll;
}
.myWickedClass > .myCoolItem {
  padding-right: 5px;
}

You need to create both roundedCorner_right.png & roundedCorner_left.png. These are work around for IE8 (& below) to fake the rounded corner feature.

So in this example above we apply the left rounded corner to the first span element in the containing div, & we apply the right rounded corner to the containing div. These images overlap the browser-provided "squary corners" & give the illusion of being part of a rounded element.

The idea for inputs would be to do the same logic. However, input is an empty element, " element is empty, it contains attributes only", in other word, you cannot wrap a span into an input such as <input><span class="myCoolItem"></span></input> to then use background images like in the previous example.

Hence the solution seems to be to do the opposite: wrap the input into another element. see this answer rounded corners of input elements in IE

Display MessageBox in ASP

If you want to do it from code behind, try this:

System.Web.UI.ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "AlertBox", "alert('Message');", true);

Convert absolute path into relative path given a current directory using Bash

Sadly, Mark Rushakoff's answer (now deleted - it referenced the code from here) does not seem to work correctly when adapted to:

source=/home/part2/part3/part4
target=/work/proj1/proj2

The thinking outlined in the commentary can be refined to make it work correctly for most cases. I'm about to assume that the script takes a source argument (where you are) and a target argument (where you want to get to), and that either both are absolute pathnames or both are relative. If one is absolute and the other relative, the easiest thing is to prefix the relative name with the current working directory - but the code below does not do that.


Beware

The code below is close to working correctly, but is not quite right.

  1. There is the problem addressed in the comments from Dennis Williamson.
  2. There is also a problem that this purely textual processing of pathnames and you can be seriously messed up by weird symlinks.
  3. The code does not handle stray 'dots' in paths like 'xyz/./pqr'.
  4. The code does not handle stray 'double dots' in paths like 'xyz/../pqr'.
  5. Trivially: the code does not remove leading './' from paths.

Dennis's code is better because it fixes 1 and 5 - but has the same issues 2, 3, 4. Use Dennis's code (and up-vote it ahead of this) because of that.

(NB: POSIX provides a system call realpath() that resolves pathnames so that there are no symlinks left in them. Applying that to the input names, and then using Dennis's code would give the correct answer each time. It is trivial to write the C code that wraps realpath() - I've done it - but I don't know of a standard utility that does so.)


For this, I find Perl easier to use than shell, though bash has decent support for arrays and could probably do this too - exercise for the reader. So, given two compatible names, split them each into components:

  • Set the relative path to empty.
  • While the components are the same, skip to the next.
  • When corresponding components are different or there are no more components for one path:
  • If there are no remaining source components and the relative path is empty, add "." to the start.
  • For each remaining source component, prefix the relative path with "../".
  • If there are no remaining target components and the relative path is empty, add "." to the start.
  • For each remaining target component, add the component to the end of the path after a slash.

Thus:

#!/bin/perl -w

use strict;

# Should fettle the arguments if one is absolute and one relative:
# Oops - missing functionality!

# Split!
my(@source) = split '/', $ARGV[0];
my(@target) = split '/', $ARGV[1];

my $count = scalar(@source);
   $count = scalar(@target) if (scalar(@target) < $count);
my $relpath = "";

my $i;
for ($i = 0; $i < $count; $i++)
{
    last if $source[$i] ne $target[$i];
}

$relpath = "." if ($i >= scalar(@source) && $relpath eq "");
for (my $s = $i; $s < scalar(@source); $s++)
{
    $relpath = "../$relpath";
}
$relpath = "." if ($i >= scalar(@target) && $relpath eq "");
for (my $t = $i; $t < scalar(@target); $t++)
{
    $relpath .= "/$target[$t]";
}

# Clean up result (remove double slash, trailing slash, trailing slash-dot).
$relpath =~ s%//%/%;
$relpath =~ s%/$%%;
$relpath =~ s%/\.$%%;

print "source  = $ARGV[0]\n";
print "target  = $ARGV[1]\n";
print "relpath = $relpath\n";

Test script (the square brackets contain a blank and a tab):

sed 's/#.*//;/^[    ]*$/d' <<! |

/home/part1/part2 /home/part1/part3
/home/part1/part2 /home/part4/part5
/home/part1/part2 /work/part6/part7
/home/part1       /work/part1/part2/part3/part4
/home             /work/part2/part3
/                 /work/part2/part3/part4

/home/part1/part2 /home/part1/part2/part3/part4
/home/part1/part2 /home/part1/part2/part3
/home/part1/part2 /home/part1/part2
/home/part1/part2 /home/part1
/home/part1/part2 /home
/home/part1/part2 /

/home/part1/part2 /work
/home/part1/part2 /work/part1
/home/part1/part2 /work/part1/part2
/home/part1/part2 /work/part1/part2/part3
/home/part1/part2 /work/part1/part2/part3/part4

home/part1/part2 home/part1/part3
home/part1/part2 home/part4/part5
home/part1/part2 work/part6/part7
home/part1       work/part1/part2/part3/part4
home             work/part2/part3
.                work/part2/part3

home/part1/part2 home/part1/part2/part3/part4
home/part1/part2 home/part1/part2/part3
home/part1/part2 home/part1/part2
home/part1/part2 home/part1
home/part1/part2 home
home/part1/part2 .

home/part1/part2 work
home/part1/part2 work/part1
home/part1/part2 work/part1/part2
home/part1/part2 work/part1/part2/part3
home/part1/part2 work/part1/part2/part3/part4

!

while read source target
do
    perl relpath.pl $source $target
    echo
done

Output from the test script:

source  = /home/part1/part2
target  = /home/part1/part3
relpath = ../part3

source  = /home/part1/part2
target  = /home/part4/part5
relpath = ../../part4/part5

source  = /home/part1/part2
target  = /work/part6/part7
relpath = ../../../work/part6/part7

source  = /home/part1
target  = /work/part1/part2/part3/part4
relpath = ../../work/part1/part2/part3/part4

source  = /home
target  = /work/part2/part3
relpath = ../work/part2/part3

source  = /
target  = /work/part2/part3/part4
relpath = ./work/part2/part3/part4

source  = /home/part1/part2
target  = /home/part1/part2/part3/part4
relpath = ./part3/part4

source  = /home/part1/part2
target  = /home/part1/part2/part3
relpath = ./part3

source  = /home/part1/part2
target  = /home/part1/part2
relpath = .

source  = /home/part1/part2
target  = /home/part1
relpath = ..

source  = /home/part1/part2
target  = /home
relpath = ../..

source  = /home/part1/part2
target  = /
relpath = ../../../..

source  = /home/part1/part2
target  = /work
relpath = ../../../work

source  = /home/part1/part2
target  = /work/part1
relpath = ../../../work/part1

source  = /home/part1/part2
target  = /work/part1/part2
relpath = ../../../work/part1/part2

source  = /home/part1/part2
target  = /work/part1/part2/part3
relpath = ../../../work/part1/part2/part3

source  = /home/part1/part2
target  = /work/part1/part2/part3/part4
relpath = ../../../work/part1/part2/part3/part4

source  = home/part1/part2
target  = home/part1/part3
relpath = ../part3

source  = home/part1/part2
target  = home/part4/part5
relpath = ../../part4/part5

source  = home/part1/part2
target  = work/part6/part7
relpath = ../../../work/part6/part7

source  = home/part1
target  = work/part1/part2/part3/part4
relpath = ../../work/part1/part2/part3/part4

source  = home
target  = work/part2/part3
relpath = ../work/part2/part3

source  = .
target  = work/part2/part3
relpath = ../work/part2/part3

source  = home/part1/part2
target  = home/part1/part2/part3/part4
relpath = ./part3/part4

source  = home/part1/part2
target  = home/part1/part2/part3
relpath = ./part3

source  = home/part1/part2
target  = home/part1/part2
relpath = .

source  = home/part1/part2
target  = home/part1
relpath = ..

source  = home/part1/part2
target  = home
relpath = ../..

source  = home/part1/part2
target  = .
relpath = ../../..

source  = home/part1/part2
target  = work
relpath = ../../../work

source  = home/part1/part2
target  = work/part1
relpath = ../../../work/part1

source  = home/part1/part2
target  = work/part1/part2
relpath = ../../../work/part1/part2

source  = home/part1/part2
target  = work/part1/part2/part3
relpath = ../../../work/part1/part2/part3

source  = home/part1/part2
target  = work/part1/part2/part3/part4
relpath = ../../../work/part1/part2/part3/part4

This Perl script works fairly thoroughly on Unix (it does not take into account all the complexities of Windows path names) in the face of weird inputs. It uses the module Cwd and its function realpath to resolve the real path of names that exist, and does a textual analysis for paths that don't exist. In all cases except one, it produces the same output as Dennis's script. The deviant case is:

source   = home/part1/part2
target   = .
relpath1 = ../../..
relpath2 = ../../../.

The two results are equivalent - just not identical. (The output is from a mildly modified version of the test script - the Perl script below simply prints the answer, rather than the inputs and the answer as in the script above.) Now: should I eliminate the non-working answer? Maybe...

#!/bin/perl -w
# Based loosely on code from: http://unix.derkeiler.com/Newsgroups/comp.unix.shell/2005-10/1256.html
# Via: http://stackoverflow.com/questions/2564634

use strict;

die "Usage: $0 from to\n" if scalar @ARGV != 2;

use Cwd qw(realpath getcwd);

my $pwd;
my $verbose = 0;

# Fettle filename so it is absolute.
# Deals with '//', '/./' and '/../' notations, plus symlinks.
# The realpath() function does the hard work if the path exists.
# For non-existent paths, the code does a purely textual hack.
sub resolve
{
    my($name) = @_;
    my($path) = realpath($name);
    if (!defined $path)
    {
        # Path does not exist - do the best we can with lexical analysis
        # Assume Unix - not dealing with Windows.
        $path = $name;
        if ($name !~ m%^/%)
        {
            $pwd = getcwd if !defined $pwd;
            $path = "$pwd/$path";
        }
        $path =~ s%//+%/%g;     # Not UNC paths.
        $path =~ s%/$%%;        # No trailing /
        $path =~ s%/\./%/%g;    # No embedded /./
        # Try to eliminate /../abc/
        $path =~ s%/\.\./(?:[^/]+)(/|$)%$1%g;
        $path =~ s%/\.$%%;      # No trailing /.
        $path =~ s%^\./%%;      # No leading ./
        # What happens with . and / as inputs?
    }
    return($path);
}

sub print_result
{
    my($source, $target, $relpath) = @_;
    if ($verbose)
    {
        print "source  = $ARGV[0]\n";
        print "target  = $ARGV[1]\n";
        print "relpath = $relpath\n";
    }
    else
    {
        print "$relpath\n";
    }
    exit 0;
}

my($source) = resolve($ARGV[0]);
my($target) = resolve($ARGV[1]);
print_result($source, $target, ".") if ($source eq $target);

# Split!
my(@source) = split '/', $source;
my(@target) = split '/', $target;

my $count = scalar(@source);
   $count = scalar(@target) if (scalar(@target) < $count);
my $relpath = "";
my $i;

# Both paths are absolute; Perl splits an empty field 0.
for ($i = 1; $i < $count; $i++)
{
    last if $source[$i] ne $target[$i];
}

for (my $s = $i; $s < scalar(@source); $s++)
{
    $relpath = "$relpath/" if ($s > $i);
    $relpath = "$relpath..";
}
for (my $t = $i; $t < scalar(@target); $t++)
{
    $relpath = "$relpath/" if ($relpath ne "");
    $relpath = "$relpath$target[$t]";
}

print_result($source, $target, $relpath);

Difference between _self, _top, and _parent in the anchor tag target attribute

Below is an image showing nested frames and the effect of different target values, followed by an explanation of the image.

Different target values.1

Imagine a webpage containing 3 nested <iframe> aka "frame"/"frameset". So:

  • the outermost webpage/browser is the starting context
  • the outermost webpage is the parent of frame 3
  • frame 3 is the parent of frame 2
  • frame 2 is the parent of frame 1
  • frame 1 is the innermost frame

Then target attributes have these effects:

  • If frame 1 has a link with target="_self", the link targets frame 1 (i.e. the link targets the frame containing the link (i.e. targets itself))
  • If frame 1 has a link with target="_parent", the link targets frame 2 (i.e. the link targets the parent frame)
  • If frame 1 has a link with target="_top", the link targets the initial webpage (i.e. the link targets the topmost/outermost frame; (in this case; the link skips past the grandparent frame 3))
    • If frame 2 has a link with target="_top", the link also targets the initial webpage (i.e. again, the link targets the topmost/outermost frame)
  • If any of these frames has a link with target="_blank", the link targets an auxiliary browsing context, aka a "new window"/"new tab"

Access to the requested object is only available from the local network phpmyadmin

Hey, use these section of code.

Path for xampp is: apache\conf\extra\httpd-xampp.conf

 <LocationMatch "^/(?i:(?:xampp|security|licenses|phpmyadmin|webalizer|server-status|server-info))">
        Order deny,allow
        Allow from all
        #Allow from ::1 127.0.0.0/8 \
             #      fc00::/7 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 \
               #    fe80::/10 169.254.0.0/16

        ErrorDocument 403 /error/HTTP_XAMPP_FORBIDDEN.html.var
    </LocationMatch>

How do I keep a label centered in WinForms?

If you don't want to dock label in whole available area, just set SizeChanged event instead of TextChanged. Changing each letter will change the width property of label as well as its text when autosize property set to True. So, by the way you can use any formula to keep label centered in form.

private void lblReport_SizeChanged(object sender, EventArgs e)
{
    lblReport.Left = (this.ClientSize.Width - lblReport.Size.Width) / 2;
}

How do I make a self extract and running installer

Okay I have got it working, hope this information is useful.

  1. First of all I now realize that not only do self-extracting zip start extracting with doubleclick, but they require no extraction application to be installed on the users computer because the extractor code is in the archive itself. This means that you will get a different user experience depending on what you application you use to create the sfx

  2. I went with WinRar as follows, this does not require you to create an sfx file, everything can be created via the gui:

    • Select files, right click and select Add to Archive
    • Use Browse.. to create the archive in the folder above
    • Change Archive Format to Zip
    • Enable Create SFX archive
    • Select Advanced tab
    • Select SFX Options
    • Select Setup tab
    • Enter setup.exe into the Run after Extraction field
    • Select Modes tab
    • Enable Unpack to temporary folder
    • Select text and Icon tab
    • Enter a more appropriate title for your task
    • Select OK
    • Select OK

The resultant exe unzips to a temporary folder and then starts the installer

Select a Dictionary<T1, T2> with LINQ

var dictionary = (from x in y 
                  select new SomeClass
                  {
                      prop1 = value1,
                      prop2 = value2
                  }
                  ).ToDictionary(item => item.prop1);

That's assuming that SomeClass.prop1 is the desired Key for the dictionary.

submit a form in a new tab

This will also work great, u can do something else while a new tab handler the submit .

<form target="_blank">
    <a href="#">Submit</a>
</form>

<script>
    $('a').click(function () {
        // do something you want ...

        $('form').submit();
    });
</script>

Codeigniter displays a blank page instead of error messages

If you get net::ERR_CONTENT_DECODING_FAILED in the console then you are using gzip in your .htaccess file but gzip encoding is Off.

Enable zlib.output_compression=On in php.ini and restart Apache

Can you display HTML5 <video> as a full screen background?

Use position:fixed on the video, set it to 100% width/height, and put a negative z-index on it so it appears behind everything.

If you look at VideoJS, the controls are just html elements sitting on top of the video, using z-index to make sure they're above.

HTML

<video id="video_background" src="video.mp4" autoplay>

(Add webm and ogg sources to support more browsers)

CSS

#video_background {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  z-index: -1000;
}

It'll work in most HTML5 browsers, but probably not iPhone/iPad, where the video needs to be activated, and doesn't like elements over it.

Undefined reference to static class member

Regarding the second question: push_ref takes reference as a parameter, and you cannot have a reference to static const memeber of a class/struct. Once you call static_cast, a temporary variable is created. And a reference to this object can be passed, everything works just fine.

Or at least my colleague who resolved this said so.

How to check if an element exists in the xml using xpath?

take look at my example

<tocheading language="EN"> 
     <subj-group> 
         <subject>Editors Choice</subject> 
         <subject>creative common</subject> 
     </subj-group> 
</tocheading> 

now how to check if creative common is exist

tocheading/subj-group/subject/text() = 'creative common'

hope this help you

How do I display image in Alert/confirm box in Javascript?

Short answer: You can't.

Long answer: You could use a modal to display a popup with the image you need.

You can refer to this as an example to a modal.

What is the symbol for whitespace in C?

#include <stdio.h>
main()
{
int c,sp,tb,nl;
sp = 0;
tb = 0;
nl = 0;
while((c = getchar()) != EOF)
{
   switch( c )
{
   case ' ':
        ++sp;
     printf("space:%d\n", sp);
     break;
   case  '\t':
        ++tb;
     printf("tab:%d\n", tb);
     break;
   case '\n':
        ++nl;
     printf("new line:%d\n", nl);
     break;
  }
 }
}

Count number of rows per group and add result to original data frame

Another way that generalizes more:

df$count <- unsplit(lapply(split(df, df[c("name","type")]), nrow), df[c("name","type")])

BarCode Image Generator in Java

There is a free library called barcode4j

HTML select dropdown list

Try this:

_x000D_
_x000D_
<select>_x000D_
    <option value="" disabled="disabled" selected="selected">Please select a name</option>_x000D_
    <option value="1">One</option>_x000D_
    <option value="2">Two</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

When the page loads, this option will be selected by default. However, as soon as the drop-down is clicked, the user won't be able to re-select this option.

Hope this helps.

Button Width Match Parent

         OutlineButton(
              onPressed: () {
                logInButtonPressed(context);
              },
              child: Container(
                width: MediaQuery.of(context).size.width / 2,
                child: Text(
                  “Log in”,
                  textAlign: TextAlign.center,
                ),
              ),
            )

Something like this works for me.

How to set focus to a button widget programmatically?

Yeah it's possible.

Button myBtn = (Button)findViewById(R.id.myButtonId);
myBtn.requestFocus();

or in XML

<Button ...><requestFocus /></Button>

Important Note: The button widget needs to be focusable and focusableInTouchMode. Most widgets are focusable but not focusableInTouchMode by default. So make sure to either set it in code

myBtn.setFocusableInTouchMode(true);

or in XML

android:focusableInTouchMode="true"

Objective C - Assign, Copy, Retain

Updated Answer for Changed Documentation

The information is now spread across several guides in the documentation. Here's a list of required reading:

The answer to this question now depends entirely on whether you're using an ARC-managed application (the modern default for new projects) or forcing manual memory management.

Assign vs. Weak - Use assign to set a property's pointer to the address of the object without retaining it or otherwise curating it; use weak to have the property point to nil automatically if the object assigned to it is deallocated. In most cases you'll want to use weak so you're not trying to access a deallocated object (illegal access of a memory address - "EXC_BAD_ACCESS") if you don't perform proper cleanup.

Retain vs. Copy - Declared properties use retain by default (so you can simply omit it altogether) and will manage the object's reference count automatically whether another object is assigned to the property or it's set to nil; Use copy to automatically send the newly-assigned object a -copy message (which will create a copy of the passed object and assign that copy to the property instead - useful (even required) in some situations where the assigned object might be modified after being set as a property of some other object (which would mean that modification/mutation would apply to the property as well).

Insert variable values in the middle of a string

1 You can use string.Replace method

var sample = "testtesttesttest#replace#testtesttest";
var result = sample.Replace("#replace#", yourValue);

2 You can also use string.Format

var result = string.Format("your right part {0} Your left Part", yourValue);

3 You can use Regex class

How to update std::map after using the find method?

std::map::find returns an iterator to the found element (or to the end() if the element was not found). So long as the map is not const, you can modify the element pointed to by the iterator:

std::map<char, int> m;
m.insert(std::make_pair('c', 0));  // c is for cookie

std::map<char, int>::iterator it = m.find('c'); 
if (it != m.end())
    it->second = 42;

jQuery attr('onclick')

As @Richard pointed out above, the onClick needs to have a capital 'C'.

$('#stop').click(function() {
     $('next').attr('onClick','stopMoving()');
}

Checkboxes in web pages – how to make them bigger?

Actually there is a way to make them bigger, checkboxes just like anything else (even an iframe like a facebook button).

Wrap them in a "zoomed" element:

_x000D_
_x000D_
.double {_x000D_
  zoom: 2;_x000D_
  transform: scale(2);_x000D_
  -ms-transform: scale(2);_x000D_
  -webkit-transform: scale(2);_x000D_
  -o-transform: scale(2);_x000D_
  -moz-transform: scale(2);_x000D_
  transform-origin: 0 0;_x000D_
  -ms-transform-origin: 0 0;_x000D_
  -webkit-transform-origin: 0 0;_x000D_
  -o-transform-origin: 0 0;_x000D_
  -moz-transform-origin: 0 0;_x000D_
}
_x000D_
<div class="double">_x000D_
  <input type="checkbox" name="hello" value="1">_x000D_
</div>
_x000D_
_x000D_
_x000D_

It might look a little bit "rescaled" but it works.

Of course you can make that div float:left and put your label besides it, float:left too.

How to change plot background color?

The easiest thing is probably to provide the color when you create the plot :

fig1 = plt.figure(facecolor=(1, 1, 1))

or

fig1, (ax1, ax2) = plt.subplots(nrows=1, ncols=2, facecolor=(1, 1, 1))

useState set method not reflecting change immediately

You can solve it by using the useRef hook but then it's will not re-render when it' updated. I have created a hooks called useStateRef, that give you the good from both worlds. It's like a state that when it's updated the Component re-render, and it's like a "ref" that always have the latest value.

See this example:

var [state,setState,ref]=useStateRef(0)

It works exactly like useState but in addition, it gives you the current state under ref.current

Learn more:

Going through a text file line by line in C

In addition to the other answers, on a recent C library (Posix 2008 compliant), you could use getline. See this answer (to a related question).

What are the differences between C, C# and C++ in terms of real-world applications?

C is the bare-bones, simple, clean language that makes you do everything yourself. It doesn't hold your hand, it doesn't stop you from shooting yourself in the foot. But it has everything you need to do what you want.

C++ is C with classes added, and then a whole bunch of other things, and then some more stuff. It doesn't hold your hand, but it'll let you hold your own hand, with add-on GC, or RAII and smart-pointers. If there's something you want to accomplish, chances are there's a way to abuse the template system to give you a relatively easy syntax for it. (moreso with C++0x). This complexity also gives you the power to accidentally create a dozen instances of yourself and shoot them all in the foot.

C# is Microsoft's stab at improving on C++ and Java. Tons of syntactical features, but no where near the complexity of C++. It runs in a full managed environment, so memory management is done for you. It does let you "get dirty" and use unsafe code if you need to, but it's not the default, and you have to do some work to shoot yourself.

@AspectJ pointcut for all methods of a class with specific annotation

You should combine a type pointcut with a method pointcut.

These pointcuts will do the work to find all public methods inside a class marked with an @Monitor annotation:

@Pointcut("within(@org.rejeev.Monitor *)")
public void beanAnnotatedWithMonitor() {}

@Pointcut("execution(public * *(..))")
public void publicMethod() {}

@Pointcut("publicMethod() && beanAnnotatedWithMonitor()")
public void publicMethodInsideAClassMarkedWithAtMonitor() {}

Advice the last pointcut that combines the first two and you're done!

If you're interested, I have written a cheat sheet with @AspectJ style here with a corresponding example document here.

Check substring exists in a string in C

#include <stdio.h>
#include <string.h>

int findSubstr(char *inpText, char *pattern);
int main()
{
    printf("Hello, World!\n");
    char *Text = "This is my sample program";
    char *pattern = "sample";
    int pos = findSubstr(Text, pattern);
    if (pos > -1) {
        printf("Found the substring at position %d \n", pos);
    }
    else
        printf("No match found \n");

    return 0;
}

int findSubstr(char *inpText, char *pattern) {
    int inplen = strlen(inpText);
    while (inpText != NULL) {

        char *remTxt = inpText;
        char *remPat = pattern;

        if (strlen(remTxt) < strlen(remPat)) {
            /* printf ("length issue remTxt %s \nremPath %s \n", remTxt, remPat); */
            return -1;
        }

        while (*remTxt++ == *remPat++) {
            printf("remTxt %s \nremPath %s \n", remTxt, remPat);
            if (*remPat == '\0') {
                printf ("match found \n");
                return inplen - strlen(inpText+1);
            }
            if (remTxt == NULL) {
                return -1;
            }
        }
        remPat = pattern;

        inpText++;
    }
}

Execute JavaScript code stored as a string

new Function('alert("Hello")')();

I think this is the best way.

Create a menu Bar in WPF?

<DockPanel>
    <Menu DockPanel.Dock="Top">
        <MenuItem Header="_File">
            <MenuItem Header="_Open"/>
            <MenuItem Header="_Close"/>
            <MenuItem Header="_Save"/>
        </MenuItem>
    </Menu>
    <StackPanel></StackPanel>
</DockPanel>

Perl: Use s/ (replace) and return new string

If you have Perl 5.14 or greater, you can use the /r option with the substitution operator to perform non-destructive substitution:

print "bla: ", $myvar =~ s/a/b/r, "\n";

In earlier versions you can achieve the same using a do() block with a temporary lexical variable, e.g.:

print "bla: ", do { (my $tmp = $myvar) =~ s/a/b/; $tmp }, "\n";

JavaScript click event listener on class

You can use the code below:

document.body.addEventListener('click', function (evt) {
    if (evt.target.className === 'databox') {
        alert(this)
    }
}, false);

java.util.Date and getYear()

The java documentation suggests to make use of Calendar class instead of this deprecated way Here is the sample code to set up the calendar object

Calendar calendar = Calendar.getInstance();
calendar.setTime(new Date());

Here is the sample code to get the year, month, etc.

System.out.println(calendar.get(Calendar.YEAR));
System.out.println(calendar.get(Calendar.MONTH));

Calendar also has support for many other useful information like, TIME, DAY_OF_MONTH, etc. Here the documentation listing all of them Please note that the month are 0 based. January is 0th month.

How can I use custom fonts on a website?

Yes, there is a way. Its called custom fonts in CSS.Your CSS needs to be modified, and you need to upload those fonts to your website.

The CSS required for this is:

@font-face {
     font-family: Thonburi-Bold;
     src: url('pathway/Thonburi-Bold.otf'); 
}

CSS Styling for a Button: Using <input type="button> instead of <button>

In your .button CSS, try display:inline-block. See this JSFiddle

Can one do a for each loop in java in reverse order?

This will mess with the original list and also needs to be called outside of the loop. Also you don't want to perform a reverse every time you loop - would that be true if one of the Iterables.reverse ideas was applied?

Collections.reverse(stringList);

for(String string: stringList){
//...do something
}

What is String pool in Java?

When the JVM loads classes, or otherwise sees a literal string, or some code interns a string, it adds the string to a mostly-hidden lookup table that has one copy of each such string. If another copy is added, the runtime arranges it so that all the literals refer to the same string object. This is called "interning". If you say something like

String s = "test";
return (s == "test");

it'll return true, because the first and second "test" are actually the same object. Comparing interned strings this way can be much, much faster than String.equals, as there's a single reference comparison rather than a bunch of char comparisons.

You can add a string to the pool by calling String.intern(), which will give you back the pooled version of the string (which could be the same string you're interning, but you'd be crazy to rely on that -- you often can't be sure exactly what code has been loaded and run up til now and interned the same string). The pooled version (the string returned from intern) will be equal to any identical literal. For example:

String s1 = "test";
String s2 = new String("test");  // "new String" guarantees a different object

System.out.println(s1 == s2);  // should print "false"

s2 = s2.intern();
System.out.println(s1 == s2);  // should print "true"

ERROR 1067 (42000): Invalid default value for 'created_at'

You can do it like this:

 CREATE TABLE `ttt` (
  `id` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT,
  `t1` TIMESTAMP  NULL DEFAULT '0000-00-00 00:00:00',
  `t2` TIMESTAMP  NULL DEFAULT '0000-00-00 00:00:00',
  `t3` TIMESTAMP  NULL DEFAULT '0000-00-00 00:00:00',
  `t4` TIMESTAMP  NULL DEFAULT 0,
  PRIMARY KEY (`id`)
) ENGINE=INNODB DEFAULT CHARSET=utf8;
  • Because the TIMESTAMP value is stored as Epoch Seconds, the timestamp value '1970-01-01 00:00:00' (UTC) is reserved since the second #0 is used to represent '0000-00-00 00:00:00'.
  • In MariaDB 5.5 and before there could only be one TIMESTAMP column per table that had CURRENT_TIMESTAMP defined as its default value. This limit has no longer applied since MariaDB 10.0.

see: https://mariadb.com/kb/en/mariadb/timestamp/

sample

MariaDB []> insert into ttt (id) VALUES (1),(2),(3);
Query OK, 3 rows affected (0.01 sec)
Records: 3  Duplicates: 0  Warnings: 0

MariaDB []> select * from ttt;
+----+---------------------+---------------------+---------------------+---------------------+
| id | t1                  | t2                  | t3                  | t4                  |
+----+---------------------+---------------------+---------------------+---------------------+
|  1 | 0000-00-00 00:00:00 | 2000-01-01 12:01:02 | 0000-00-00 00:00:00 | 0000-00-00 00:00:00 |
|  2 | 0000-00-00 00:00:00 | 2000-01-01 12:01:02 | 0000-00-00 00:00:00 | 0000-00-00 00:00:00 |
|  3 | 0000-00-00 00:00:00 | 2000-01-01 12:01:02 | 0000-00-00 00:00:00 | 0000-00-00 00:00:00 |
+----+---------------------+---------------------+---------------------+---------------------+
3 rows in set (0.00 sec)

MariaDB []>

What is the equivalent of "none" in django templates?

You can also use the built-in template filter default:

If value evaluates to False (e.g. None, an empty string, 0, False); the default "--" is displayed.

{{ profile.user.first_name|default:"--" }}

Documentation: https://docs.djangoproject.com/en/dev/ref/templates/builtins/#default

How do you convert a byte array to a hexadecimal string in C?

I'll add the C++ version here for anyone who is interested.

#include <iostream>
#include <iomanip>
inline void print_bytes(char const * buffer, std::size_t count, std::size_t bytes_per_line, std::ostream & out) {
    std::ios::fmtflags flags(out.flags()); // Save flags before manipulation.
    out << std::hex << std::setfill('0');
    out.setf(std::ios::uppercase);
    for (std::size_t i = 0; i != count; ++i) {
        auto current_byte_number = static_cast<unsigned int>(static_cast<unsigned char>(buffer[i]));
        out << std::setw(2) << current_byte_number;
        bool is_end_of_line = (bytes_per_line != 0) && ((i + 1 == count) || ((i + 1) % bytes_per_line == 0));
        out << (is_end_of_line ? '\n' : ' ');
    }
    out.flush();
    out.flags(flags); // Restore original flags.
}

It will print the hexdump of the buffer of length count to std::ostream out (you can make it default to std::cout). Every line will contain bytes_per_line bytes, each byte is represented using uppercase two digit hex. There will be a space between bytes. And at end of line or end of buffer it will print a newline. If bytes_per_line is set to 0, then it will not print new_line. Try for yourself.

What does "The APR based Apache Tomcat Native library was not found" mean?

On Mac OS X:

$ brew install tomcat-native
==> tomcat-native
In order for tomcat's APR lifecycle listener to find this library, you'll
need to add it to java.library.path. This can be done by adding this line
to $CATALINA_HOME/bin/setenv.sh

  CATALINA_OPTS="$CATALINA_OPTS -Djava.library.path=/usr/local/opt/tomcat-native/lib"

If $CATALINA_HOME/bin/setenv.sh doesn't exist, create it and make it executable.

Then add it to the eclipse's tomcat arguments (double-click Server > Open Launch Configuration > Arguments tab > VM arguments)

-Djava.library.path=/usr/local/opt/tomcat-native/lib

PHP: Limit foreach() statement?

In PHP 5.5+, you can do

function limit($iterable, $limit) {
    foreach ($iterable as $key => $value) {
        if (!$limit--) break;
        yield $key => $value;
    }
}

foreach (limit($arr, 10) as $key => $value) {
    // do stuff
}

Generators rock.

Easiest way to activate PHP and MySQL on Mac OS 10.6 (Snow Leopard), 10.7 (Lion), 10.8 (Mountain Lion)?

If you've upgraded to Mac OS X 10.8 Mountain Lion, and previously had a working system, all you should need to do is re-enable PHP as in Step 1 of the above chosen answer.

You may also find the following Preference Pane useful for managing "web sharing" (Apache web server), which replaces system functionality removed in OS X 10.8: http://clickontyler.com/blog/2012/02/web-sharing-mountain-lion/

I also had to re-add my virtual hosts include line to the httpd.conf

How to set default Checked in checkbox ReactJS?

Don't make it too hard. First, understand a simple example given below. It will be clear to you. In this case, just after pressing the checkbox, we will grab the value from the state(initially it's false), change it to other value(initially it's true) & set the state accordingly. If the checkbox is pressed for the second time, it will do the same process again. Grabbing the value (now it's true), change it(to false) & then set the state accordingly(now it's false again. The code is shared below.

Part 1

state = {
  verified: false
} // The verified state is now false

Part 2

verifiedChange = e => {
  // e.preventDefault(); It's not needed
  const { verified } = e.target;
  this.setState({
    verified: !this.state.verified // It will make the default state value(false) at Part 1 to true 
  });
}; 

Part 3

  <form> 
      <input
          type="checkbox"
          name="verified"
          id="verified"
          onChange={this.verifiedChange} // Triggers the function in the Part 2
          value={this.state.verified}
      />
      <label for="verified">
      <small>Verified</small>
      </label>
  </form>

How to loop through a dataset in powershell?

The parser is having trouble concatenating your string. Try this:

write-host 'value is : '$i' '$($ds.Tables[1].Rows[$i][0])

Edit: Using double quotes might also be clearer since you can include the expressions within the quoted string:

write-host "value is : $i $($ds.Tables[1].Rows[$i][0])"

How do I run a node.js app as a background service?

UPDATE - As mentioned in one of the answers below, PM2 has some really nice functionality missing from forever. Consider using it.

Original Answer

Use nohup:

nohup node server.js &

EDIT I wanted to add that the accepted answer is really the way to go. I'm using forever on instances that need to stay up. I like to do npm install -g forever so it's in the node path and then just do forever start server.js

How to loop through all elements of a form jQuery

I have found this simple jquery snippet, to be handy for choosing just the type of selectors I want to work with:


$("select, input").each(function(){
     // do some stuff with the element
});

C#: Printing all properties of an object

Don't think so. I've always had to write them or use someone else's work to get that info. Has to be reflection as far as i'm aware.

EDIT:
Check this out. I was investigating some debugging on long object graphs and noticed this when i Add Watches, VS throws in this class: Mscorlib_CollectionDebugView<>. It's an internal type for displaying collections nicely for viewing in the watch windows/code debug modes. Now coz it's internal you can reference it, but u can use Reflector to copy (from mscorlib) the code and have your own (the link above has a copy/paste example). Looks really useful.

How can I check out a GitHub pull request with git?

That gist does describe what happend when you do a git fetch:

Obviously, change the github url to match your project's URL. It ends up looking like this:

[remote "origin"]
    fetch = +refs/heads/*:refs/remotes/origin/*
    url = [email protected]:joyent/node.git
    fetch = +refs/pull/*/head:refs/remotes/origin/pr/*

Now fetch all the pull requests:

$ git fetch origin
From github.com:joyent/node
 * [new ref]         refs/pull/1000/head -> origin/pr/1000
 * [new ref]         refs/pull/1002/head -> origin/pr/1002
 * [new ref]         refs/pull/1004/head -> origin/pr/1004
 * [new ref]         refs/pull/1009/head -> origin/pr/1009
...

To check out a particular pull request:

$ git checkout pr/999
Branch pr/999 set up to track remote branch pr/999 from origin.
Switched to a new branch 'pr/999'

You have various scripts listed in issues 259 to automate that task.
The git-extras project proposes the command git-pr (implemented in PR 262)

git-pr(1) -- Checks out a pull request locally

SYNOPSIS

git-pr <number> [<remote>]
git-pr clean

DESCRIPTION

Creates a local branch based on a GitHub pull request number, and switch to that branch afterwards.

The name of the remote to fetch from. Defaults to origin.

EXAMPLES

This checks out the pull request 226 from origin:

$ git pr 226

remote: Counting objects: 12, done.
remote: Compressing objects: 100% (9/9), done.
remote: Total 12 (delta 3), reused 9 (delta 3)
Unpacking objects: 100% (12/12), done.
From https://github.com/visionmedia/git-extras
  * [new ref] refs/pull/226/head -> pr/226
Switched to branch 'pr/226'

What are the differences between json and simplejson Python modules?

json seems faster than simplejson in both cases of loads and dumps in latest version

Tested versions:

  • python: 3.6.8
  • json: 2.0.9
  • simplejson: 3.16.0

Results:

>>> def test(obj, call, data, times):
...   s = datetime.now()
...   print("calling: ", call, " in ", obj, " ", times, " times") 
...   for _ in range(times):
...     r = getattr(obj, call)(data)
...   e = datetime.now()
...   print("total time: ", str(e-s))
...   return r

>>> test(json, "dumps", data, 10000)
calling:  dumps  in  <module 'json' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\json\\__init__.py'>   10000  times
total time:  0:00:00.054857

>>> test(simplejson, "dumps", data, 10000)
calling:  dumps  in  <module 'simplejson' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\site-packages\\simplejson\\__init__.py'>   10000  times
total time:  0:00:00.419895
'{"1": 100, "2": "acs", "3.5": 3.5567, "d": [1, "23"], "e": {"a": "A"}}'

>>> test(json, "loads", strdata, 1000)
calling:  loads  in  <module 'json' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\json\\__init__.py'>   1000  times
total time:  0:00:00.004985
{'1': 100, '2': 'acs', '3.5': 3.5567, 'd': [1, '23'], 'e': {'a': 'A'}}

>>> test(simplejson, "loads", strdata, 1000)
calling:  loads  in  <module 'simplejson' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\site-packages\\simplejson\\__init__.py'>   1000  times
total time:  0:00:00.040890
{'1': 100, '2': 'acs', '3.5': 3.5567, 'd': [1, '23'], 'e': {'a': 'A'}}

For versions:

  • python: 3.7.4
  • json: 2.0.9
  • simplejson: 3.17.0

json was faster than simplejson during dumps operation but both maintained the same speed during loads operations

How do you reset the stored credentials in 'git credential-osxkeychain'?

git-credential-osxkeychain stores passwords in the Apple Keychain, as noted above.

By default, gitcredentials only considers the domain name. If you want Git to consider the full path (e.g. if you have multiple GitHub accounts), set the useHttpPath variable to true, as described at http://git-scm.com/docs/gitcredentials.html. Note that changing this setting will ask your credentials again for each URL.

set serveroutput on in oracle procedure

First add next code in your sp:

BEGIN
    dbms_output.enable();
    dbms_output.put_line ('TEST LINE'); 
END;

Compile your code in your Oracle SQL developer. So go to Menu View--> dbms output. Click on Icon Green Plus and select your schema. Run your sp now.

How to check if a variable is an integer or a string?

In my opinion you have two options:

  • Just try to convert it to an int, but catch the exception:

    try:
        value = int(value)
    except ValueError:
        pass  # it was a string, not an int.
    

    This is the Ask Forgiveness approach.

  • Explicitly test if there are only digits in the string:

    value.isdigit()
    

    str.isdigit() returns True only if all characters in the string are digits (0-9).

    The unicode / Python 3 str type equivalent is unicode.isdecimal() / str.isdecimal(); only Unicode decimals can be converted to integers, as not all digits have an actual integer value (U+00B2 SUPERSCRIPT 2 is a digit, but not a decimal, for example).

    This is often called the Ask Permission approach, or Look Before You Leap.

The latter will not detect all valid int() values, as whitespace and + and - are also allowed in int() values. The first form will happily accept ' +10 ' as a number, the latter won't.

If your expect that the user normally will input an integer, use the first form. It is easier (and faster) to ask for forgiveness rather than for permission in that case.

Close dialog on click (anywhere)

Facing the same problem, I have created a small plugin that enables to close a dialog when clicking outside of it whether it a modal or non-modal dialog. It supports one or multiple dialogs on the same page.

More information on my website here: http://www.coheractio.com/blog/closing-jquery-ui-dialog-widget-when-clicking-outside

Laurent

What is the role of the bias in neural networks?

Bias determines how much angle your weight will rotate.

In 2-dimensional chart, weight and bias can help us to find the decision boundary of outputs.

Say we need to build a AND function, the input(p)-output(t) pair should be

{p=[0,0], t=0},{p=[1,0], t=0},{p=[0,1], t=0},{p=[1,1], t=1}

enter image description here

Now we need to find a decision boundary, the ideal boundary should be:

enter image description here

See? W is perpendicular to our boundary. Thus, we say W decided the direction of boundary.

However, it is hard to find correct W at first time. Mostly, we choose original W value randomly. Thus, the first boundary may be this: enter image description here

Now the boundary is pareller to y axis.

We want to rotate boundary, how?

By changing the W.

So, we use the learning rule function: W'=W+P: enter image description here

W'=W+P is equivalent to W'=W+bP, while b=1.

Therefore, by changing the value of b(bias), you can decide the angle between W' and W. That is "the learning rule of ANN".

You could also read Neural Network Design by Martin T. Hagan / Howard B. Demuth / Mark H. Beale, chapter 4 "Perceptron Learning Rule"

Section vs Article HTML5

A section is basically a wrapper for h1 (or other h tags) and the content that corresponds to this. An article is essentially a document within your document that is repeated or paginated...like each blog post on your document can be an article, or each comment on your document can be an article.

PHP import Excel into database (xls & xlsx)

If you can convert .xls to .csv before processing, you can use the query below to import the csv to the database:

load data local infile 'FILE.CSV' into table TABLENAME fields terminated by ',' enclosed by '"' lines terminated by '\n' (FIELD1,FIELD2,FIELD3)

jQuery: Performing synchronous AJAX requests

As you're making a synchronous request, that should be

function getRemote() {
    return $.ajax({
        type: "GET",
        url: remote_url,
        async: false
    }).responseText;
}

Example - http://api.jquery.com/jQuery.ajax/#example-3

PLEASE NOTE: Setting async property to false is deprecated and in the process of being removed (link). Many browsers including Firefox and Chrome have already started to print a warning in the console if you use this:

Chrome:

Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check https://xhr.spec.whatwg.org/.

Firefox:

Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user’s experience. For more help http://xhr.spec.whatwg.org/

only integers, slices (`:`), ellipsis (`...`), numpy.newaxis (`None`) and integer or boolean arrays are valid indices

I believe your problem is this: in your while loop, n is divided by 2, but never cast as an integer again, so it becomes a float at some point. It is then added onto y, which is then a float too, and that gives you the warning.

How can we store into an NSDictionary? What is the difference between NSDictionary and NSMutableDictionary?

The key difference: NSMutableDictionary can be modified in place, NSDictionary cannot. This is true for all the other NSMutable* classes in Cocoa. NSMutableDictionary is a subclass of NSDictionary, so everything you can do with NSDictionary you can do with both. However, NSMutableDictionary also adds complementary methods to modify things in place, such as the method setObject:forKey:.

You can convert between the two like this:

NSMutableDictionary *mutable = [[dict mutableCopy] autorelease];
NSDictionary *dict = [[mutable copy] autorelease]; 

Presumably you want to store data by writing it to a file. NSDictionary has a method to do this (which also works with NSMutableDictionary):

BOOL success = [dict writeToFile:@"/file/path" atomically:YES];

To read a dictionary from a file, there's a corresponding method:

NSDictionary *dict = [NSDictionary dictionaryWithContentsOfFile:@"/file/path"];

If you want to read the file as an NSMutableDictionary, simply use:

NSMutableDictionary *dict = [NSMutableDictionary dictionaryWithContentsOfFile:@"/file/path"];

What is the iOS 6 user agent string?

Some more:

Mozilla/5.0 (iPhone; CPU iPhone OS 6_1_3 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10B329 Safari/8536.25

Mozilla/5.0 (iPhone; CPU iPhone OS 6_1_4 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10B350 Safari/8536.25

Android: View.setID(int id) programmatically - how to avoid ID conflicts?

In order to dynamically generate View Id form API 17 use

generateViewId()

Which will generate a value suitable for use in setId(int). This value will not collide with ID values generated at build time by aapt for R.id.

How do I execute code AFTER a form has loaded?

First time it WILL NOT start "AfterLoading",
It will just register it to start NEXT Load.

private void Main_Load(object sender, System.EventArgs e)
{
    //Register it to Start in Load 
    //Starting from the Next time.
    this.Activated += AfterLoading;
}

private void AfterLoading(object sender, EventArgs e)
{
    this.Activated -= AfterLoading;
    //Write your code here.
}

Python - Convert a bytes array into JSON format

To convert this bytesarray directly to json, you could first convert the bytesarray to a string with decode(), utf-8 is standard. Change the quotation markers.. The last step is to remove the " from the dumped string, to change the json object from string to list.

dumps(s.decode()).replace("'", '"')[1:-1]

Pandas: Creating DataFrame from Series

I guess anther way, possibly faster, to achieve this is 1) Use dict comprehension to get desired dict (i.e., taking 2nd col of each array) 2) Then use pd.DataFrame to create an instance directly from the dict without loop over each col and concat.

Assuming your mat looks like this (you can ignore this since your mat is loaded from file):

In [135]: mat = {'a': np.random.randint(5, size=(4,2)),
   .....: 'b': np.random.randint(5, size=(4,2))}

In [136]: mat
Out[136]: 
{'a': array([[2, 0],
        [3, 4],
        [0, 1],
        [4, 2]]), 'b': array([[1, 0],
        [1, 1],
        [1, 0],
        [2, 1]])}

Then you can do:

In [137]: df = pd.DataFrame ({name:mat[name][:,1] for name in mat})

In [138]: df
Out[138]: 
   a  b
0  0  0
1  4  1
2  1  0
3  2  1

[4 rows x 2 columns]

Difference between "git add -A" and "git add ."

A more distilled quick answer:

Does both below (same as git add --all)

git add -A

Stages new + modified files

git add .

Stages modified + deleted files

git add -u

How do I create a pause/wait function using Qt?

This previous question mentions using qSleep() which is in the QtTest module. To avoid the overhead linking in the QtTest module, looking at the source for that function you could just make your own copy and call it. It uses defines to call either Windows Sleep() or Linux nanosleep().

#ifdef Q_OS_WIN
#include <windows.h> // for Sleep
#endif
void QTest::qSleep(int ms)
{
    QTEST_ASSERT(ms > 0);

#ifdef Q_OS_WIN
    Sleep(uint(ms));
#else
    struct timespec ts = { ms / 1000, (ms % 1000) * 1000 * 1000 };
    nanosleep(&ts, NULL);
#endif
}

How do I specify "not equals to" when comparing strings in an XSLT <xsl:if>?

If you want to compare to a string literal you need to put it in (single) quotes:

<xsl:if test="Count != 'N/A'">

How do I recognize "#VALUE!" in Excel spreadsheets?

This will return TRUE for #VALUE! errors (ERROR.TYPE = 3) and FALSE for anything else.

=IF(ISERROR(A1),ERROR.TYPE(A1)=3)

jQuery select change event get selected option

Another and short way to get value of selected value,

$('#selectElement').on('change',function(){
   var selectedVal = $(this).val();
                       ^^^^  ^^^^ -> presents #selectElement selected value 
                         |
                         v
               presents #selectElement, 
});

Postgresql: error "must be owner of relation" when changing a owner object

This solved my problem : Sample alter table statement to change the ownership.

ALTER TABLE databasechangelog OWNER TO arwin_ash;
ALTER TABLE databasechangeloglock OWNER TO arwin_ash;

Add text at the end of each line

sed 's/.*/&:80/'  abcd.txt >abcde.txt

How to remove selected commit log entries from a Git repository while keeping their changes?

You can use git cherry-pick for this. 'cherry-pick' will apply a commit onto the branch your on now.

then do

git rebase --hard <SHA1 of A>

then apply the D and E commits.

git cherry-pick <SHA1 of D>
git cherry-pick <SHA1 of E>

This will skip out the B and C commit. Having said that it might be impossible to apply the D commit to the branch without B, so YMMV.

How to get current working directory in Java?

If you want to get your current working directory then use the following line

System.out.println(new File("").getAbsolutePath());

Floating point comparison functions for C#

I translated the sample from Michael Borgwardt. This is the result:

public static bool NearlyEqual(float a, float b, float epsilon){
    float absA = Math.Abs (a);
    float absB = Math.Abs (b);
    float diff = Math.Abs (a - b);

    if (a == b) {
        return true;
    } else if (a == 0 || b == 0 || diff < float.Epsilon) {
        // a or b is zero or both are extremely close to it
        // relative error is less meaningful here
        return diff < epsilon;
    } else { // use relative error
        return diff / (absA + absB) < epsilon;
    }
}

Feel free to improve this answer.

UITableView set to static cells. Is it possible to hide some of the cells programmatically?

The best way is as described in the following blog http://ali-reynolds.com/2013/06/29/hide-cells-in-static-table-view/

Design your static table view as normal in interface builder – complete with all potentially hidden cells. But there is one thing you must do for every potential cell that you want to hide – check the “Clip subviews” property of the cell, otherwise the content of the cell doesn’t disappear when you try and hide it (by shrinking it’s height – more later).

SO – you have a switch in a cell and the switch is supposed to hide and show some static cells. Hook it up to an IBAction and in there do this:

[self.tableView beginUpdates];
[self.tableView endUpdates];

That gives you nice animations for the cells appearing and disappearing. Now implement the following table view delegate method:

- (float)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    if (indexPath.section == 1 && indexPath.row == 1) { // This is the cell to hide - change as you need
    // Show or hide cell
        if (self.mySwitch.on) {
            return 44; // Show the cell - adjust the height as you need
        } else {
            return 0; // Hide the cell
        }
   }
   return 44;
}

And that’s it. Flip the switch and the cell hides and reappears with a nice, smooth animation.

How to make a transparent HTML button?

To get rid of the outline when clicking, add outline:none

jsFiddle example

button {
    background-color: Transparent;
    background-repeat:no-repeat;
    border: none;
    cursor:pointer;
    overflow: hidden;
    outline:none;
}

_x000D_
_x000D_
button {_x000D_
    background-color: Transparent;_x000D_
    background-repeat:no-repeat;_x000D_
    border: none;_x000D_
    cursor:pointer;_x000D_
    overflow: hidden;_x000D_
    outline:none;_x000D_
}
_x000D_
<button>button</button>
_x000D_
_x000D_
_x000D_

Programmatically register a broadcast receiver

for LocalBroadcastManager

   Intent intent = new Intent("any.action.string");
   LocalBroadcastManager.getInstance(context).
                                sendBroadcast(intent);

and register in onResume

LocalBroadcastManager.getInstance(
                    ActivityName.this).registerReceiver(chatCountBroadcastReceiver, filter);

and Unregister it onStop

LocalBroadcastManager.getInstance(
                ActivityName.this).unregisterReceiver(chatCountBroadcastReceiver);

and recieve it ..

mBroadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            Log.e("mBroadcastReceiver", "onReceive");
        }
    };

where IntentFilter is

 new IntentFilter("any.action.string")

How to check if field is null or empty in MySQL?

Either use

SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1 
from tablename

or

SELECT case when field1 IS NULL or field1 = ''
            then 'empty'
            else field1
       end as field1 
from tablename

If you only want to check for null and not for empty strings then you can also use ifnull() or coalesce(field1, 'empty'). But that is not suitable for empty strings.

type checking in javascript

Try this code:

 alert(typeof(1) == "number");

Formatting code in Notepad++

In my notepad++, it seems TextFX needs a perl environment to format HTML files. Tidy2 demands nothing so I think it's more handy.

Global keyboard capture in C# application

If a global hotkey would suffice, then RegisterHotKey would do the trick

Are PHP short tags acceptable to use?

Short tag are alwayes available in php. So you do not need echo the first statement in your script

example:

    $a =10;
    <?= $a;//10 
    echo "Hellow";//
    echo "Hellow";

   ?>

Suddenly you need to use for a single php script then u can use it. example:

<html>
<head>
<title></title>
</head>  
<body>
<p>hellow everybody<?= hi;?></p>
<p>hellow everybody  </p> 
<p>hellow everybody  </p>   
</body>
</html>

How to change the font size and color of x-axis and y-axis label in a scatterplot with plot function in R?

Look at ?par for the various graphics parameters.

In general cex controls size, col controls colour. If you want to control the colour of a label, the par is col.lab, the colour of the axis annotations col.axis, the colour of the main text, col.main etc. The names are quite intuitive, once you know where to begin.

For example

x <- 1:10
y <- 1:10

plot(x , y,xlab="x axis", ylab="y axis",  pch=19, col.axis = 'blue', col.lab = 'red', cex.axis = 1.5, cex.lab = 2)

enter image description here

If you need to change the colour / style of the surrounding box and axis lines, then look at ?axis or ?box, and you will find that you will be using the same parameter names within calls to box and axis.

You have a lot of control to make things however you wish.

eg

plot(x , y,xlab="x axis", ylab="y axis",  pch=19,  cex.lab = 2, axes = F,col.lab = 'red')
box(col = 'lightblue')
axis(1, col = 'blue', col.axis = 'purple', col.ticks = 'darkred', cex.axis = 1.5, font = 2, family = 'serif')
axis(2, col = 'maroon', col.axis = 'pink', col.ticks = 'limegreen', cex.axis = 0.9, font =3, family = 'mono')

enter image description here

Which is seriously ugly, but shows part of what you can control

Picking a random element from a set

This is faster than the for-each loop in the accepted answer:

int index = rand.nextInt(set.size());
Iterator<Object> iter = set.iterator();
for (int i = 0; i < index; i++) {
    iter.next();
}
return iter.next();

The for-each construct calls Iterator.hasNext() on every loop, but since index < set.size(), that check is unnecessary overhead. I saw a 10-20% boost in speed, but YMMV. (Also, this compiles without having to add an extra return statement.)

Note that this code (and most other answers) can be applied to any Collection, not just Set. In generic method form:

public static <E> E choice(Collection<? extends E> coll, Random rand) {
    if (coll.size() == 0) {
        return null; // or throw IAE, if you prefer
    }

    int index = rand.nextInt(coll.size());
    if (coll instanceof List) { // optimization
        return ((List<? extends E>) coll).get(index);
    } else {
        Iterator<? extends E> iter = coll.iterator();
        for (int i = 0; i < index; i++) {
            iter.next();
        }
        return iter.next();
    }
}

Better way to call javascript function in a tag

Modern browsers support a Content Security Policy or CSP. This is the highest level of web security and strongly recommended if you can apply it because it completely blocks all XSS attacks.

Both of your suggestions break with CSP enabled because they allow inline Javascript (which could be injected by a hacker) to execute in your page.

The best practice is to subscribe to the event in Javascript, as in Konrad Rudolph's answer.

Best C# API to create PDF

I used PdfSharp. It's free, open source and quite convenient to use, but I can't say whether it is the best or not, because I haven't really used anything else.

JavaScript: Check if mouse button down?

Regarding Pax' solution: it doesn't work if user clicks more than one button intentionally or accidentally. Don't ask me how I know :-(.

The correct code should be like that:

var mouseDown = 0;
document.body.onmousedown = function() { 
  ++mouseDown;
}
document.body.onmouseup = function() {
  --mouseDown;
}

With the test like this:

if(mouseDown){
  // crikey! isn't she a beauty?
}

If you want to know what button is pressed, be prepared to make mouseDown an array of counters and count them separately for separate buttons:

// let's pretend that a mouse doesn't have more than 9 buttons
var mouseDown = [0, 0, 0, 0, 0, 0, 0, 0, 0],
    mouseDownCount = 0;
document.body.onmousedown = function(evt) { 
  ++mouseDown[evt.button];
  ++mouseDownCount;
}
document.body.onmouseup = function(evt) {
  --mouseDown[evt.button];
  --mouseDownCount;
}

Now you can check what buttons were pressed exactly:

if(mouseDownCount){
  // alright, let's lift the little bugger up!
  for(var i = 0; i < mouseDown.length; ++i){
    if(mouseDown[i]){
      // we found it right there!
    }
  }
}

Now be warned that the code above would work only for standard-compliant browsers that pass you a button number starting from 0 and up. IE uses a bit mask of currently pressed buttons:

  • 0 for "nothing is pressed"
  • 1 for left
  • 2 for right
  • 4 for middle
  • and any combination of above, e.g., 5 for left + middle

So adjust your code accordingly! I leave it as an exercise.

And remember: IE uses a global event object called … "event".

Incidentally IE has a feature useful in your case: when other browsers send "button" only for mouse button events (onclick, onmousedown, and onmouseup), IE sends it with onmousemove too. So you can start listening for onmousemove when you need to know the button state, and check for evt.button as soon as you got it — now you know what mouse buttons were pressed:

// for IE only!
document.body.onmousemove = function(){
  if(event.button){
    // aha! we caught a feisty little sheila!
  }
};

Of course you get nothing if she plays dead and not moving.

Relevant links:

Update #1: I don't know why I carried over the document.body-style of code. It will be better to attach event handlers directly to the document.

Open a PDF using VBA in Excel

If it's a matter of just opening PDF to send some keys to it then why not try this

Sub Sample()
    ActiveWorkbook.FollowHyperlink "C:\MyFile.pdf"
End Sub

I am assuming that you have some pdf reader installed.

Is there a rule-of-thumb for how to divide a dataset into training and validation sets?

It all depends on the data at hand. If you have considerable amount of data then 80/20 is a good choice as mentioned above. But if you do not Cross-Validation with a 50/50 split might help you a lot more and prevent you from creating a model over-fitting your training data.

How do I use hexadecimal color strings in Flutter?

A simple function without using a class:

Color _colorFromHex(String hexColor) {
  final hexCode = hexColor.replaceAll('#', '');
  return Color(int.parse('FF$hexCode', radix: 16));
}

You can use it like this:

Color color1 = _colorFromHex("b74093");
Color color2 = _colorFromHex("#b74093");

Case insensitive 'in'

My 5 (wrong) cents

'a' in "".join(['A']).lower()

UPDATE

Ouch, totally agree @jpp, I'll keep as an example of bad practice :(

How to read from a text file using VBScript?

Dim obj : Set obj = CreateObject("Scripting.FileSystemObject")
Dim outFile : Set outFile = obj.CreateTextFile("in.txt")
Dim inFile: Set inFile = obj.OpenTextFile("out.txt")

' Read file
Dim strRetVal : strRetVal = inFile.ReadAll
inFile.Close

' Write file
outFile.write (strRetVal)
outFile.Close

Pandas left outer join multiple dataframes on multiple columns

One can also do this with a compact version of @TomAugspurger's answer, like so:

df = df1.merge(df2, how='left', on=['Year', 'Week', 'Colour']).merge(df3[['Week', 'Colour', 'Val3']], how='left', on=['Week', 'Colour'])

How do I run PHP code when a user clicks on a link?

either send the user to another page which does it

<a href="exec.php">Execute PHP</a>

or do it with ajax

<script type="text/javascript">
// <![CDATA[
    document.getElementById('link').onclick = function() {
        // call script via ajax...
        return false;
    }
// ]]>
</script>
...
<a href="#" id="link">Execute PHP</a>

Uncaught TypeError: Object #<Object> has no method 'movingBoxes'

I had the same problem. I changed the order of the scripts in the head part, and it worked for me. Every script the plugin needs - needs to stay close.

For example:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.5.1/jquery.min.js"></script>
<script type="text/javascript" src="http://cloud.github.com/downloads/malsup/cycle/jquery.cycle.all.latest.js"></script>
<script type="text/javascript"> 
$(document).ready(function() {
    $('#slider').cycle({
            fx: 'fade' 
        });
    });
</script>

EditText request focus

>>you can write your code like

  if (TextUtils.isEmpty(username)) {
            editTextUserName.setError("Please enter username");
            editTextUserName.requestFocus();
            return;
        }

        if (TextUtils.isEmpty(password)) {
            editTextPassword.setError("Enter a password");
            editTextPassword.requestFocus();
            return;
        }

Remove the last three characters from a string

myString = myString.Remove(myString.Length - 3, 3);

How to filter Android logcat by application?

put this to applog.sh

#!/bin/sh
PACKAGE=$1
APPPID=`adb -d shell ps | grep "${PACKAGE}" | cut -c10-15 | sed -e 's/ //g'`
adb -d logcat -v long \
 | tr -d '\r' | sed -e '/^\[.*\]/ {N; s/\n/ /}' | grep -v '^$' \
 | grep " ${APPPID}:"

then: applog.sh com.example.my.package

How do you implement a re-try-catch?

This is an old question but a solution is still relevant. Here is my generic solution in Java 8 without using any third party library:

public interface RetryConsumer<T> {
    T evaluate() throws Throwable;
}
public interface RetryPredicate<T> {
    boolean shouldRetry(T t);
}
public class RetryOperation<T> {
    private RetryConsumer<T> retryConsumer;
    private int noOfRetry;
    private int delayInterval;
    private TimeUnit timeUnit;
    private RetryPredicate<T> retryPredicate;
    private List<Class<? extends Throwable>> exceptionList;

    public static class OperationBuilder<T> {
        private RetryConsumer<T> iRetryConsumer;
        private int iNoOfRetry;
        private int iDelayInterval;
        private TimeUnit iTimeUnit;
        private RetryPredicate<T> iRetryPredicate;
        private Class<? extends Throwable>[] exceptionClasses;

        private OperationBuilder() {
        }

        public OperationBuilder<T> retryConsumer(final RetryConsumer<T> retryConsumer) {
            this.iRetryConsumer = retryConsumer;
            return this;
        }

        public OperationBuilder<T> noOfRetry(final int noOfRetry) {
            this.iNoOfRetry = noOfRetry;
            return this;
        }

        public OperationBuilder<T> delayInterval(final int delayInterval, final TimeUnit timeUnit) {
            this.iDelayInterval = delayInterval;
            this.iTimeUnit = timeUnit;
            return this;
        }

        public OperationBuilder<T> retryPredicate(final RetryPredicate<T> retryPredicate) {
            this.iRetryPredicate = retryPredicate;
            return this;
        }

        @SafeVarargs
        public final OperationBuilder<T> retryOn(final Class<? extends Throwable>... exceptionClasses) {
            this.exceptionClasses = exceptionClasses;
            return this;
        }

        public RetryOperation<T> build() {
            if (Objects.isNull(iRetryConsumer)) {
                throw new RuntimeException("'#retryConsumer:RetryConsumer<T>' not set");
            }

            List<Class<? extends Throwable>> exceptionList = new ArrayList<>();
            if (Objects.nonNull(exceptionClasses) && exceptionClasses.length > 0) {
                exceptionList = Arrays.asList(exceptionClasses);
            }
            iNoOfRetry = iNoOfRetry == 0 ? 1 : 0;
            iTimeUnit = Objects.isNull(iTimeUnit) ? TimeUnit.MILLISECONDS : iTimeUnit;
            return new RetryOperation<>(iRetryConsumer, iNoOfRetry, iDelayInterval, iTimeUnit, iRetryPredicate, exceptionList);
        }
    }

    public static <T> OperationBuilder<T> newBuilder() {
        return new OperationBuilder<>();
    }

    private RetryOperation(RetryConsumer<T> retryConsumer, int noOfRetry, int delayInterval, TimeUnit timeUnit,
                           RetryPredicate<T> retryPredicate, List<Class<? extends Throwable>> exceptionList) {
        this.retryConsumer = retryConsumer;
        this.noOfRetry = noOfRetry;
        this.delayInterval = delayInterval;
        this.timeUnit = timeUnit;
        this.retryPredicate = retryPredicate;
        this.exceptionList = exceptionList;
    }

    public T retry() throws Throwable {
        T result = null;
        int retries = 0;
        while (retries < noOfRetry) {
            try {
                result = retryConsumer.evaluate();
                if (Objects.nonNull(retryPredicate)) {
                    boolean shouldItRetry = retryPredicate.shouldRetry(result);
                    if (shouldItRetry) {
                        retries = increaseRetryCountAndSleep(retries);
                    } else {
                        return result;
                    }
                } else {
                    // no retry condition defined, no exception thrown. This is the desired result.
                    return result;
                }
            } catch (Throwable e) {
                retries = handleException(retries, e);
            }
        }
        return result;
    }

    private int handleException(int retries, Throwable e) throws Throwable {
        if (exceptionList.contains(e.getClass()) || (exceptionList.isEmpty())) {
            // exception is excepted, continue retry.
            retries = increaseRetryCountAndSleep(retries);
            if (retries == noOfRetry) {
                // evaluation is throwing exception, no more retry left. Throw it.
                throw e;
            }
        } else {
            // unexpected exception, no retry required. Throw it.
            throw e;
        }
        return retries;
    }

    private int increaseRetryCountAndSleep(int retries) {
        retries++;
        if (retries < noOfRetry && delayInterval > 0) {
            try {
                timeUnit.sleep(delayInterval);
            } catch (InterruptedException ignore) {
                Thread.currentThread().interrupt();
            }
        }
        return retries;
    }
}

Let's have a test case like:

@Test
public void withPredicateAndException() {
    AtomicInteger integer = new AtomicInteger();
    try {
        Integer result = RetryOperation.<Integer>newBuilder()
                .retryConsumer(() -> {
                    int i = integer.incrementAndGet();
                    if (i % 2 == 1) {
                        throw new NumberFormatException("Very odd exception");
                    } else {
                        return i;
                    }
                })
                .noOfRetry(10)
                .delayInterval(10, TimeUnit.MILLISECONDS)
                .retryPredicate(value -> value <= 6)
                .retryOn(NumberFormatException.class, EOFException.class)
                .build()
                .retry();
        Assert.assertEquals(8, result.intValue());
    } catch (Throwable throwable) {
        Assert.fail();
    }
}

Show only two digit after decimal

First thing that should pop in a developer head while formatting a number into char sequence should be care of such details like do it will be possible to reverse the operation.

And other aspect is providing proper result. So you want to truncate the number or round it.

So before you start you should ask your self, am i interested on the value or not.

To achieve your goal you have multiple options but most of them refer to Format and Formatter, but i just suggest to look in this answer.

Cannot open backup device. Operating System error 5

Please check the access to drives.First create one folder and go to folder properties ,

You may find the security tab ,click on that check whether your user id having the access or not.

if couldn't find the your id,please click the add buttion and give user name with full access.

Changing selection in a select with the Chosen plugin

In case of multiple type of select and/or if you want to remove already selected items one by one, directly within a dropdown list items, you can use something like:

jQuery("body").on("click", ".result-selected", function() {
    var locID = jQuery(this).attr('class').split('__').pop();
    // I have a class name: class="result-selected locvalue__209"
    var arrayCurrent = jQuery('#searchlocation').val();
    var index = arrayCurrent.indexOf(locID);
    if (index > -1) {
        arrayCurrent.splice(index, 1);
    }
    jQuery('#searchlocation').val(arrayCurrent).trigger('chosen:updated');
});

Convert DataFrame column type from string to datetime, dd/mm/yyyy format

If you have a mixture of formats in your date, don't forget to set infer_datetime_format=True to make life easier.

df['date'] = pd.to_datetime(df['date'], infer_datetime_format=True)

Source: pd.to_datetime

or if you want a customized approach:

def autoconvert_datetime(value):
    formats = ['%m/%d/%Y', '%m-%d-%y']  # formats to try
    result_format = '%d-%m-%Y'  # output format
    for dt_format in formats:
        try:
            dt_obj = datetime.strptime(value, dt_format)
            return dt_obj.strftime(result_format)
        except Exception as e:  # throws exception when format doesn't match
            pass
    return value  # let it be if it doesn't match

df['date'] = df['date'].apply(autoconvert_datetime)

XML Document to String

Assuming doc is your instance of org.w3c.dom.Document:

TransformerFactory tf = TransformerFactory.newInstance();
Transformer transformer = tf.newTransformer();
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
StringWriter writer = new StringWriter();
transformer.transform(new DOMSource(doc), new StreamResult(writer));
String output = writer.getBuffer().toString().replaceAll("\n|\r", "");

How to create timer in angular2

In Addition to all the previous answers, I would do it using RxJS Observables

please check Observable.timer

Here is a sample code, will start after 2 seconds and then ticks every second:

import {Component} from 'angular2/core';
import {Observable} from 'rxjs/Rx';

@Component({
    selector: 'my-app',
    template: 'Ticks (every second) : {{ticks}}'
})
export class AppComponent {
  ticks =0;
  ngOnInit(){
    let timer = Observable.timer(2000,1000);
    timer.subscribe(t=>this.ticks = t);
  }
}

And here is a working plunker

Update If you want to call a function declared on the AppComponent class, you can do one of the following:

** Assuming the function you want to call is named func,

ngOnInit(){
    let timer = Observable.timer(2000,1000);
    timer.subscribe(this.func);
}

The problem with the above approach is that if you call 'this' inside func, it will refer to the subscriber object instead of the AppComponent object which is probably not what you want.

However, in the below approach, you create a lambda expression and call the function func inside it. This way, the call to func is still inside the scope of AppComponent. This is the best way to do it in my opinion.

ngOnInit(){
    let timer = Observable.timer(2000,1000);
    timer.subscribe(t=> {
        this.func(t);
    });
}

check this plunker for working code.

Ignore parent padding

margin: 0 -10px; 

is better than

margin: -10px;

The later sucks content vertically into it.

Split output of command by columns using Bash?

Bash's set will parse all output into position parameters.

For instance, with set $(free -h) command, echo $7 will show "Mem:"

ReferenceError: describe is not defined NodeJs

if you are using vscode, want to debug your files

I used tdd before, it throw ReferenceError: describe is not defined

But, when I use bdd, it works!

waste half day to solve it....

    {
      "type": "node",
      "request": "launch",
      "name": "Mocha Tests",
      "program": "${workspaceFolder}/node_modules/mocha/bin/_mocha",
      "args": [
        "-u",
        "bdd",// set to bdd, not tdd
        "--timeout",
        "999999",
        "--colors",
        "${workspaceFolder}/test/**/*.js"
      ],
      "internalConsoleOptions": "openOnSessionStart"
},

Remove android default action bar

I've noticed that if you set the theme in the AndroidManifest, it seems to get rid of that short time where you can see the action bar. So, try adding this to your manifest:

<android:theme="@android:style/Theme.NoTitleBar">

Just add it to your application tag to apply it app-wide.

How to bundle an Angular app for production

ng serve works for serving our application for development purposes. What about for production? If we look into our package.json file, we can see that there are scripts we can use:

"scripts": {
  "ng": "ng",
  "start": "ng serve",
  "build": "ng build --prod",
  "test": "ng test",
  "lint": "ng lint",
  "e2e": "ng e2e"
},

The build script uses the Angular CLI's ng build with the --prod flag. Let's try that now. We can do it one of two ways:

# using the npm scripts

npm run build

# using the cli directly

ng build --prod

This time we are given four files instead of the five. The --prod flag tells Angular to make our application much smaller in size.

CharSequence VS String in Java?

CharSequence is a readable sequence of char values which implements String. it has 4 methods

  1. charAt(int index)
  2. length()
  3. subSequence(int start, int end)
  4. toString()

Please refer documentation CharSequence documentation

SVN upgrade working copy

After upgrading to the latest version of Tortoise-SVN I needed to do an "Upgrade" first (as opposed to "Update"!).

Why does JPA have a @Transient annotation?

Purpose is different:

The transient keyword and @Transient annotation have two different purposes: one deals with serialization and one deals with persistence. As programmers, we often marry these two concepts into one, but this is not accurate in general. Persistence refers to the characteristic of state that outlives the process that created it. Serialization in Java refers to the process of encoding/decoding an object's state as a byte stream.

The transient keyword is a stronger condition than @Transient:

If a field uses the transient keyword, that field will not be serialized when the object is converted to a byte stream. Furthermore, since JPA treats fields marked with the transient keyword as having the @Transient annotation, the field will not be persisted by JPA either.

On the other hand, fields annotated @Transient alone will be converted to a byte stream when the object is serialized, but it will not be persisted by JPA. Therefore, the transient keyword is a stronger condition than the @Transient annotation.

Example

This begs the question: Why would anyone want to serialize a field that is not persisted to the application's database? The reality is that serialization is used for more than just persistence. In an Enterprise Java application there needs to be a mechanism to exchange objects between distributed components; serialization provides a common communication protocol to handle this. Thus, a field may hold critical information for the purpose of inter-component communication; but that same field may have no value from a persistence perspective.

For example, suppose an optimization algorithm is run on a server, and suppose this algorithm takes several hours to complete. To a client, having the most up-to-date set of solutions is important. So, a client can subscribe to the server and receive periodic updates during the algorithm's execution phase. These updates are provided using the ProgressReport object:

@Entity
public class ProgressReport implements Serializable{

    private static final long serialVersionUID = 1L;

    @Transient
    long estimatedMinutesRemaining;
    String statusMessage;
    Solution currentBestSolution;

}

The Solution class might look like this:

@Entity
public class Solution implements Serializable{

    private static final long serialVersionUID = 1L;

    double[][] dataArray;
    Properties properties;
}

The server persists each ProgressReport to its database. The server does not care to persist estimatedMinutesRemaining, but the client certainly cares about this information. Therefore, the estimatedMinutesRemaining is annotated using @Transient. When the final Solution is located by the algorithm, it is persisted by JPA directly without using a ProgressReport.

How to select specified node within Xpath node sets by index with Selenium?

This is a FAQ:

//someName[3]

means: all someName elements in the document, that are the third someName child of their parent -- there may be many such elements.

What you want is exactly the 3rd someName element:

(//someName)[3]

Explanation: the [] has a higher precedence (priority) than //. Remember always to put expressions of the type //someName in brackets when you need to specify the Nth node of their selected node-list.

React - How to pass HTML tags in props?

Actually, there are multiple ways to go with that.

You want to use JSX inside your props

You can simply use {} to cause JSX to parse the parameter. The only limitation is the same as for every JSX element: It must return only one root element.

myProp={<div><SomeComponent>Some String</div>}

The best readable way to go for this is to create a function renderMyProp that will return JSX components (just like the standard render function) and then simply call myProp={ this.renderMyProp() }

You want to pass only HTML as a string

By default, JSX doesn't let you render raw HTML from string values. However, there is a way to make it do that:

myProp="<div>This is some html</div>"

Then in your component you can use it like that:

<div dangerouslySetInnerHTML=myProp={{ __html: this.renderMyProp() }}></div>

Beware that this solution 'can' open on cross-site scripting forgeries attacks. Also beware that you can only render simple HTML, no JSX tag or component or other fancy things.

The array way

In react, you can pass an array of JSX elements. That means:

myProp={["This is html", <span>Some other</span>, "and again some other"]}

I wouldn't recommend this method because:

  • It will create a warning (missing keys)
  • It's not readable
  • It's not really the JSX way, it's more a hack than an intended design.

The children way

Adding it for the sake of completeness but in react, you can also get all children that are 'inside' your component.

So if I take the following code:

<SomeComponent>
    <div>Some content</div>
    <div>Some content</div>
</SomeComponent>

Then the two divs will be available as this.props.children in SomeComponent and can be rendered with the standard {} syntax.

This solution is perfect when you have only one HTML content to pass to your Component (Imagine a Popin component that only takes the content of the Popin as children).

However, if you have multiple contents, you can't use children (or you need at least to combine it with another solution here)

How to make a <button> in Bootstrap look like a normal link in nav-tabs?

In bootstrap 3, this works well for me:

.btn-link.btn-anchor {
    outline: none !important;
    padding: 0;
    border: 0;
    vertical-align: baseline;
}

Used like:

<button type="button" class="btn-link btn-anchor">My Button</button>

Demo

Mod of negative number is melting my brain

I like the trick presented by Peter N Lewis on this thread: "If n has a limited range, then you can get the result you want simply by adding a known constant multiple of [the divisor] that is greater that the absolute value of the minimum."

So if I have a value d that is in degrees and I want to take

d % 180f

and I want to avoid the problems if d is negative, then instead I just do this:

(d + 720f) % 180f

This assumes that although d may be negative, it is known that it will never be more negative than -720.

Android: how to create Switch case from this?

@Override
public void onClick(View v)
{
    switch (v.getId())
    {
        case R.id.:

            break;
        case R.id.:

            break;
        default:
            break;
    }
}

JavaScript checking for null vs. undefined and difference between == and ===

The spec is the place to go for full answers to these questions. Here's a summary:

  1. For a variable x, you can:

    • check whether it's null by direct comparison using ===. Example: x === null
    • check whether it's undefined by either of two basic methods: direct comparison with undefined or typeof. For various reasons, I prefer typeof x === "undefined".
    • check whether it's one of null and undefined by using == and relying on the slightly arcane type coercion rules that mean x == null does exactly what you want.

  2. The basic difference between == and === is that if the operands are of different types, === will always return false while == will convert one or both operands into the same type using rules that lead to some slightly unintuitive behaviour. If the operands are of the same type (e.g. both are strings, such as in the typeof comparison above), == and === will behave exactly the same.

More reading:

Any way to write a Windows .bat file to kill processes?

You can do this with 'taskkill'. With the /IM parameter, you can specify image names.

Example:

taskkill /im somecorporateprocess.exe

You can also do this to 'force' kill:

Example:

taskkill /f /im somecorporateprocess.exe

Just add one line per process you want to kill, save it as a .bat file, and add in your startup directory. Problem solved!

If this is a legacy system, PsKill will do the same.

Encoding as Base64 in Java

public String convertImageToBase64(String filePath) {
    byte[] fileContent = new byte[0];
    String base64encoded = null;
    try {
        fileContent = FileUtils.readFileToByteArray(new File(filePath));
    } catch (IOException e) {
        log.error("Error reading file: {}", filePath);
    }
    try {
        base64encoded = Base64.getEncoder().encodeToString(fileContent);
    } catch (Exception e) {
        log.error("Error encoding the image to base64", e);
    }
    return base64encoded;
}

Subscript out of range error in this Excel VBA script

This looks a little better than your previous version but get rid of that .Activate on that line and see if you still get that error.

Dim sh1 As Worksheet
set sh1 = Workbooks.Add(filenum(lngPosition) & ".csv")

Creates a worksheet object. Not until you create that object do you want to start working with it. Once you have that object you can do the following:

sh1.Range("A69").Paste
sh1.Range("A69").Select

The sh1. explicitely tells Excel which object you are saying to work with... otherwise if you start selecting other worksheets while this code is running you could wind up pasting data to the wrong place.

How do I use variables in Oracle SQL Developer?

Simple answer NO.

However you can achieve something similar by running the following version using bind variables:

SELECT * FROM Employees WHERE EmployeeID = :EmpIDVar 

Once you run the query above in SQL Developer you will be prompted to enter value for the bind variable EmployeeID.

"Missing return statement" within if / for / while

This will return the string only if the condition is true.

public String myMethod()
{
    if(condition)
    {
       return x;
    }
    else
       return "";
}

How do I use .toLocaleTimeString() without displaying seconds?

I wanted it with date and the time but no seconds so I used this:

var dateWithoutSecond = new Date();
dateWithoutSecond.toLocaleTimeString([], {year: 'numeric', month: 'numeric', day: 'numeric', hour: '2-digit', minute: '2-digit'});

It produced the following output:

7/29/2020, 2:46 PM

Which was the exact thing I needed. Worked in FireFox.

Preferred Java way to ping an HTTP URL for availability

Consider using the Restlet framework, which has great semantics for this sort of thing. It's powerful and flexible.

The code could be as simple as:

Client client = new Client(Protocol.HTTP);
Response response = client.get(url);
if (response.getStatus().isError()) {
    // uh oh!
}

Why does integer division in C# return an integer and not a float?

The result will always be of type that has the greater range of the numerator and the denominator. The exceptions are byte and short, which produce int (Int32).

var a = (byte)5 / (byte)2;  // 2 (Int32)
var b = (short)5 / (byte)2; // 2 (Int32)
var c = 5 / 2;              // 2 (Int32)
var d = 5 / 2U;             // 2 (UInt32)
var e = 5L / 2U;            // 2 (Int64)
var f = 5L / 2UL;           // 2 (UInt64)
var g = 5F / 2UL;           // 2.5 (Single/float)
var h = 5F / 2D;            // 2.5 (Double)
var i = 5.0 / 2F;           // 2.5 (Double)
var j = 5M / 2;             // 2.5 (Decimal)
var k = 5M / 2F;            // Not allowed

There is no implicit conversion between floating-point types and the decimal type, so division between them is not allowed. You have to explicitly cast and decide which one you want (Decimal has more precision and a smaller range compared to floating-point types).

wildcard * in CSS for classes

An alternative solution:

div[class|='tocolor'] will match for values of the "class" attribute that begin with "tocolor-", including "tocolor-1", "tocolor-2", etc.

Beware that this won't match

<div class="foo tocolor-">

Reference: https://www.w3.org/TR/css3-selectors/#attribute-representation

[att|=val]

Represents an element with the att attribute, its value either being exactly "val" or beginning with "val" immediately followed by "-" (U+002D)

jQuery: Currency Format Number

$(document).ready(function() {
    var num = $('div.number').text()
    num = addPeriod(num);
    $('div.number').text('Rp. '+num)
});

function addPeriod(nStr)
{
    nStr += '';
    x = nStr.split('.');
    x1 = x[0];
    x2 = x.length > 1 ? '.' + x[1] : '';
    var rgx = /(\d+)(\d{3})/;
    while (rgx.test(x1)) {
        x1 = x1.replace(rgx, '$1' + '.' + '$2');
    }
    return x1 + x2;
}

Use CSS3 transitions with gradient backgrounds

With Chrome 85 (and also Edge) adding support for @property rule, now we can do this in CSS:

@property --colorPrimary {
  syntax: '<color>';
  initial-value: magenta;
  inherits: false;
}

@property --colorSecondary {
  syntax: '<color>';
  initial-value: green;
  inherits: false;
}

The rest is normal CSS.
Set initial gradient colors to the variables and also set the transition of those variables:

div {
  /* Optional: change the initial value of variables
    --colorPrimary: #f64;
    --colorSecondary: brown;
  */

  background: radial-gradient(circle, var(--colorPrimary) 0%, var(--colorSecondary) 85%) no-repeat;
  transition: --colorPrimary 3s, --colorSecondary 3s;
}

Then, on the desired rule, set the new values for variables:

div:hover {  
--colorPrimary: yellow;
--colorSecondary: #f00;
}

_x000D_
_x000D_
@property --colorPrimary {
  syntax: '<color>';
  initial-value: #0f0;
  inherits: false;
}

@property --colorSecondary {
  syntax: '<color>';
  initial-value: rgb(0, 255, 255);
  inherits: false;
}

div {
  width: 200px;
  height: 100px;
  background: radial-gradient(circle, var(--colorPrimary) 0%, var(--colorSecondary) 85%) no-repeat;
  transition: --colorPrimary 3s, --colorSecondary 3s;
}

div:hover {
  --colorPrimary: red;
  --colorSecondary: #00f;
}
_x000D_
<div>Hover over me</div>
_x000D_
_x000D_
_x000D_

See the full example here and refer here for @property support status.
The @property rule is part of the CSS Houdini technology. For more info refer here and here.

Fit Image in ImageButton in Android

It worked well in my case. First, you download an image and rename it as iconimage, locates it in the drawable folder. You can change the size by setting android:layout_width or android:layout_height. Finally, we have

 <ImageButton
        android:id="@+id/answercall"
        android:layout_width="120dp"
        android:layout_height="80dp"
        android:src="@drawable/iconimage"
        android:layout_alignParentBottom="true"
        android:layout_alignParentLeft="true"
        android:scaleType="fitCenter" />

Is it possible to have a multi-line comments in R?

if(FALSE) {
...
}

precludes multiple lines from being executed. However, these lines still have to be syntactically correct, i.e., can't be comments in the proper sense. Still helpful for some cases though.

How to configure SSL certificates with Charles Web Proxy and the latest Android Emulator on Windows?

In Charles, go to Proxy>>Proxy Settings and select the SSL tab. Add your host to the list of Locations.

For example, if your secure call is going to https://secure.example.com, you can enter secure.example.com, or *.example.com.

Once the above is in place, you may need to right-click on the call in the main Charles window and select the SSL Proxying option.

Hope this helps.

What are the differences between Abstract Factory and Factory design patterns?

Abstract factory creates a base class with abstract methods defining methods for the objects that should be created. Each factory class which derives the base class can create their own implementation of each object type.

enter image description here

Factory method is just a simple method used to create objects in a class. It's usually added in the aggregate root (The Order class has a method called CreateOrderLine)

enter image description here

Abstract factory

In the example below we design an interface so that we can decouple queue creation from a messaging system and can therefore create implementations for different queue systems without having to change the code base.

interface IMessageQueueFactory
{
  IMessageQueue CreateOutboundQueue(string name);
  IMessageQueue CreateReplyQueue(string name);
}

public class AzureServiceBusQueueFactory : IMessageQueueFactory
{
      IMessageQueue CreateOutboundQueue(string name)
      {
           //init queue
           return new AzureMessageQueue(/*....*/);
      }

      IMessageQueue CreateReplyQueue(string name)
      {
           //init response queue
           return new AzureResponseMessageQueue(/*....*/);
      }

}

public class MsmqFactory : IMessageQueueFactory
{
      IMessageQueue CreateOutboundQueue(string name)
      {
           //init queue
           return new MsmqMessageQueue(/*....*/);
      }

      IMessageQueue CreateReplyQueue(string name)
      {
           //init response queue
           return new MsmqResponseMessageQueue(/*....*/);
      }
}

Factory method

The problem in HTTP servers is that we always need an response for every request.

public interface IHttpRequest
{
    // .. all other methods ..

    IHttpResponse CreateResponse(int httpStatusCode);
}

Without the factory method, the HTTP server users (i.e. programmers) would be forced to use implementation specific classes which defeat the purpose of the IHttpRequest interface.

Therefore we introduce the factory method so that the creation of the response class also is abstracted away.

Summary

The difference is that the intended purpose of the class containing a factory method is not to create objects, while an abstract factory should only be used to create objects.

One should take care when using factory methods since it's easy to break the LSP (Liskov Substitution principle) when creating objects.

C# delete a folder and all files and folders within that folder

Try this.

namespace EraseJunkFiles
{
    class Program
    {
        static void Main(string[] args)
        {
            DirectoryInfo yourRootDir = new DirectoryInfo(@"C:\somedirectory\");
            foreach (DirectoryInfo dir in yourRootDir.GetDirectories())
                    DeleteDirectory(dir.FullName, true);
        }
        public static void DeleteDirectory(string directoryName, bool checkDirectiryExist)
        {
            if (Directory.Exists(directoryName))
                Directory.Delete(directoryName, true);
            else if (checkDirectiryExist)
                throw new SystemException("Directory you want to delete is not exist");
        }
    }
}

Sorting A ListView By Column

Use the ListView.SortExpression.

When multiple columns are sorted, this property contains a comma-separated list of the fields to sort by.

How to place and center text in an SVG rectangle

The previous answers gave poor results when using rounded corners or stroke-width that's >1 . For example, you would expect the following code to produce a rounded rectangle, but the corners are clipped by the parent svg component:

_x000D_
_x000D_
<svg width="200" height="100">_x000D_
  <!--this rect should have rounded corners-->_x000D_
  <rect x="0" y="0" rx="5" ry="5" width="200" height="100" stroke="red" stroke-width="10px" fill="white"/>_x000D_
  <text x="50%" y="50%" alignment-baseline="middle" text-anchor="middle">CLIPPED BORDER</text>    _x000D_
</svg>
_x000D_
_x000D_
_x000D_

Instead, I recommend wrapping the text in a svg and then nesting that new svg and the rect together inside a g element, as in the following example:

_x000D_
_x000D_
<!--the outer svg here-->_x000D_
<svg width="400px" height="300px">_x000D_
_x000D_
  <!--the rect/text group-->_x000D_
  <g transform="translate(50,50)">_x000D_
    <rect rx="5" ry="5" width="200" height="100" stroke="green" fill="none" stroke-width="10"/>_x000D_
    <svg width="200px" height="100px">_x000D_
      <text x="50%" y="50%" alignment-baseline="middle" text-anchor="middle">CORRECT BORDER</text>      _x000D_
    </svg>_x000D_
  </g>_x000D_
_x000D_
  <!--rest of the image's code-->_x000D_
</svg>
_x000D_
_x000D_
_x000D_

This fixes the clipping problem that occurs in the answers above. I also translated the rect/text group using the transform="translate(x,y)" attribute to demonstrate that this provides a more intuitive approach to positioning the rect/text on-screen.

Different color for each bar in a bar chart; ChartJS

After looking into the Chart.Bar.js file I've managed to find the solution. I've used this function to generate a random color:

function getRandomColor() {
    var letters = '0123456789ABCDEF'.split('');
    var color = '#';
    for (var i = 0; i < 6; i++ ) {
        color += letters[Math.floor(Math.random() * 16)];
    }
    return color;
}

I've added it to the end of the file and i called this function right inside the "fillColor:" under

helpers.each(dataset.data,function(dataPoint,index){
                    //Add a new point for each piece of data, passing any required data to draw.

so now it looks like this:

helpers.each(dataset.data,function(dataPoint,index){
                    //Add a new point for each piece of data, passing any required data to draw.

                    datasetObject.bars.push(new this.BarClass({
                        value : dataPoint,
                        label : data.labels[index],
                        datasetLabel: dataset.label,
                        strokeColor : dataset.strokeColor,
                        fillColor : getRandomColor(),
                        highlightFill : dataset.highlightFill || dataset.fillColor,
                        highlightStroke : dataset.highlightStroke || dataset.strokeColor
                    }));
                },this);

and it works I get different color for each bar.

How to return a class object by reference in C++?

I will show you some examples:

First example, do not return local scope object, for example:

const string &dontDoThis(const string &s)
{
    string local = s;
    return local;
}

You can't return local by reference, because local is destroyed at the end of the body of dontDoThis.

Second example, you can return by reference:

const string &shorterString(const string &s1, const string &s2)
{
    return (s1.size() < s2.size()) ? s1 : s2;
}

Here, you can return by reference both s1 and s2 because they were defined before shorterString was called.

Third example:

char &get_val(string &str, string::size_type ix)
{
    return str[ix];
}

usage code as below:

string s("123456");
cout << s << endl;
char &ch = get_val(s, 0); 
ch = 'A';
cout << s << endl; // A23456

get_val can return elements of s by reference because s still exists after the call.

Fourth example

class Student
{
public:
    string m_name;
    int age;    

    string &getName();
};

string &Student::getName()
{
    // you can return by reference
    return m_name;
}

string& Test(Student &student)
{
    // we can return `m_name` by reference here because `student` still exists after the call
    return stu.m_name;
}

usage example:

Student student;
student.m_name = 'jack';
string name = student.getName();
// or
string name2 = Test(student);

Fifth example:

class String
{
private:
    char *str_;

public:
    String &operator=(const String &str);
};

String &String::operator=(const String &str)
{
    if (this == &str)
    {
        return *this;
    }
    delete [] str_;
    int length = strlen(str.str_);
    str_ = new char[length + 1];
    strcpy(str_, str.str_);
    return *this;
}

You could then use the operator= above like this:

String a;
String b;
String c = b = a;

Android Failed to install HelloWorld.apk on device (null) Error

Try changing the ADB connection timeout. I think it defaults that to 5000ms and I changed mine to 10000ms to get rid of that problem. If you are in Eclipse, you can do this by going through Window -> Preferences and then it is in DDMS under Android.

As described here: Android error: Failed to install *.apk on device *: timeout

How do I install PIL/Pillow for Python 3.6?

Pillow is released with installation wheels on Windows:

We provide Pillow binaries for Windows compiled for the matrix of supported Pythons in both 32 and 64-bit versions in wheel, egg, and executable installers. These binaries have all of the optional libraries included

https://pillow.readthedocs.io/en/3.3.x/installation.html#basic-installation

Update: Python 3.6 is now supported by Pillow. Install with pip install pillow and check https://pillow.readthedocs.io/en/latest/installation.html for more information.


However, Python 3.6 is still in alpha and not officially supported yet, although the tests do all pass for the nightly Python builds (currently 3.6a4).

https://travis-ci.org/python-pillow/Pillow/jobs/155605577

If it's somehow possible to install the 3.5 wheel for 3.6, that's your best bet. Otherwise, zlib notwithstanding, you'll need to build from source, requiring an MS Visual C++ compiler, and which isn't straightforward. For tips see:

https://pillow.readthedocs.io/en/3.3.x/installation.html#building-from-source

And also see how it's built for Windows on AppVeyor CI (but not yet 3.5 or 3.6):

https://github.com/python-pillow/Pillow/tree/master/winbuild

Failing that, downgrade to Python 3.5 or wait until 3.6 is supported by Pillow, probably closer to the 3.6's official release.

PowerShell The term is not recognized as cmdlet function script file or operable program

For the benefit of searchers, there is another way you can produce this error message - by missing the $ off the script block name when calling it.

e.g. I had a script block like so:

$qa = {
    param($question, $answer)
    Write-Host "Question = $question, Answer = $answer"
}

I tried calling it using:

&qa -question "Do you like powershell?" -answer "Yes!"

But that errored. The correct way was:

&$qa -question "Do you like powershell?" -answer "Yes!"

Run Command Prompt Commands

you can use simply write the code in a .bat format extension ,the code of the batch file :

c:/ copy /b Image1.jpg + Archive.rar Image2.jpg

use this c# code :

Process.Start("file_name.bat")

vertical-align with Bootstrap 3

HTML

<div class="row">
    <div class="col-xs-2 pull-bottom"
         style="height:100px;background:blue">
    </div>
    <div class="col-xs-8 pull-bottom"
         style="height:50px;background:yellow">
    </div>
</div>

CSS

.pull-bottom {
    display: inline-block;
    vertical-align: bottom;
    float: none;
}

What is the best way to find the users home directory in Java?

Others have answered the question before me but a useful program to print out all available properties is:

for (Map.Entry<?,?> e : System.getProperties().entrySet()) {
    System.out.println(String.format("%s = %s", e.getKey(), e.getValue())); 
}

LOAD DATA INFILE Error Code : 13

  1. GRANT ALL PRIVILEGES ON db_name.* TO 'db_user'@'localhost';
  2. GRANT FILE on .* to 'db_user'@'localhost' IDENTIFIED BY 'password';
  3. FLUSH PRIVILEGES;
  4. SET GLOBAL local_infile = 1;
  5. Variable in the config of the MYSQL "secure-file-priv" must be empty line!!!

Centering the image in Bootstrap

Use This as the solution

This worked for me perfectly..

<div align="center">
   <img src="">
</div>

How to POST JSON Data With PHP cURL?

Please try this code:-

$url = 'url_to_post';

$data = array("first_name" => "First name","last_name" => "last name","email"=>"[email protected]","addresses" => array ("address1" => "some address" ,"city" => "city","country" => "CA", "first_name" =>  "Mother","last_name" =>  "Lastnameson","phone" => "555-1212", "province" => "ON", "zip" => "123 ABC" ) );

$data_string = json_encode(array("customer" =>$data));

$ch = curl_init($url);

curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string);

curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type:application/json'));

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

$result = curl_exec($ch);

curl_close($ch);

echo "$result";

Using reCAPTCHA on localhost

when you add Domains in Google recaptcha

Add new domain: Localhost not localhost

"L" is capital letter

Good luck

What does it mean to inflate a view from an xml file?

Because we make UI into XML but view objects is what we display so we somehow need to convert xml into view objects so inflating means we are converting xml into view objects so that it can be displayed, for this we need a service called layout inflator service and give it an xml and it will be convert for you.

How to put data containing double-quotes in string variable?

You can escape (this is how this principle is called) the double quotes by prefixing them with another double quote. You can put them in a string as follows:

Dim MyVar as string = "some text ""hello"" "

This will give the MyVar variable a value of some text "hello".