Programs & Examples On #Byte order mark

A byte order mark (BOM) is a Unicode character used to signal the order of bytes in a text file or stream. As the BOM is U+FEFF, it makes it clear whether the high-order bytes are first (stream starts FE.FF) or second (stream starts FF.FE).

How do I remove  from the beginning of a file?

In Notepad++, choose the "Encoding" menu, then "Encode in UTF-8 without BOM". Then save.

See Stack Overflow question How to make Notepad to save text in UTF-8 without BOM?.

Convert UTF-8 with BOM to UTF-8 with no BOM in Python

You can use codecs.

import codecs
with open("test.txt",'r') as filehandle:
    content = filehandle.read()
if content[:3] == codecs.BOM_UTF8:
    content = content[3:]
print content.decode("utf-8")

How can I output a UTF-8 CSV in PHP that Excel will read properly?

EASY solution for Mac Excel 2008: I struggled with this soo many times, but here was my easy fix: Open the .csv file in Textwrangler which should open your UTF-8 chars correctly. Now in the bottom status bar change the file format from "Unicode (UTF-8)" to "Western (ISO Latin 1)" and save the file. Now go to your Mac Excel 2008 and select File > Import > Select csv > Find your file > in File origin select "Windows (ANSI)" and voila the UTF-8 chars are showing correctly. At least it does for me...

Set Encoding of File to UTF8 With BOM in Sublime Text 3

By default, Sublime Text set 'UTF8 without BOM', but that wasn't specified.

The only specicified things is 'UTF8 with BOM'.

Hope this help :)

Write to UTF-8 file in Python

Read the following: http://docs.python.org/library/codecs.html#module-encodings.utf_8_sig

Do this

with codecs.open("test_output", "w", "utf-8-sig") as temp:
    temp.write("hi mom\n")
    temp.write(u"This has ?")

The resulting file is UTF-8 with the expected BOM.

What's the difference between UTF-8 and UTF-8 without BOM?

The other excellent answers already answered that:

  • There is no official difference between UTF-8 and BOM-ed UTF-8
  • A BOM-ed UTF-8 string will start with the three following bytes. EF BB BF
  • Those bytes, if present, must be ignored when extracting the string from the file/stream.

But, as additional information to this, the BOM for UTF-8 could be a good way to "smell" if a string was encoded in UTF-8... Or it could be a legitimate string in any other encoding...

For example, the data [EF BB BF 41 42 43] could either be:

  • The legitimate ISO-8859-1 string "ABC"
  • The legitimate UTF-8 string "ABC"

So while it can be cool to recognize the encoding of a file content by looking at the first bytes, you should not rely on this, as show by the example above

Encodings should be known, not divined.

Using PowerShell to write a file in UTF-8 without the BOM

important!: this only works if an extra space or newline at the start is no problem for your use case of the file
(e.g. if it is an SQL file, Java file or human readable text file)

one could use a combination of creating an empty (non-UTF8 or ASCII (UTF8-compatible)) file and appending to it (replace $str with gc $src if the source is a file):

" "    |  out-file  -encoding ASCII  -noNewline  $dest
$str  |  out-file  -encoding UTF8   -append     $dest

as one-liner

replace $dest and $str according to your use case:

$_ofdst = $dest ; " " | out-file -encoding ASCII -noNewline $_ofdst ; $src | out-file -encoding UTF8 -append $_ofdst

as simple function

function Out-File-UTF8-noBOM { param( $str, $dest )
  " "    |  out-file  -encoding ASCII  -noNewline  $dest
  $str  |  out-file  -encoding UTF8   -append     $dest
}

using it with a source file:

Out-File-UTF8-noBOM  (gc $src),  $dest

using it with a string:

Out-File-UTF8-noBOM  $str,  $dest
  • optionally: continue appending with Out-File:

    "more foo bar"  |  Out-File -encoding UTF8 -append  $dest
    

How to detect the character encoding of a text file?

Several answers are here but nobody has posted usefull code.

Here is my code that detects all encodings that Microsoft detects in Framework 4 in the StreamReader class.

Obviously you must call this function immediately after opening the stream before reading anything else from the stream because the BOM are the first bytes in the stream.

This function requires a Stream that can seek (for example a FileStream). If you have a Stream that cannot seek you must write a more complicated code that returns a Byte buffer with the bytes that have already been read but that are not BOM.

/// <summary>
/// UTF8    : EF BB BF
/// UTF16 BE: FE FF
/// UTF16 LE: FF FE
/// UTF32 BE: 00 00 FE FF
/// UTF32 LE: FF FE 00 00
/// </summary>
public static Encoding DetectEncoding(Stream i_Stream)
{
    if (!i_Stream.CanSeek || !i_Stream.CanRead)
        throw new Exception("DetectEncoding() requires a seekable and readable Stream");

    // Try to read 4 bytes. If the stream is shorter, less bytes will be read.
    Byte[] u8_Buf = new Byte[4];
    int s32_Count = i_Stream.Read(u8_Buf, 0, 4);
    if (s32_Count >= 2)
    {
        if (u8_Buf[0] == 0xFE && u8_Buf[1] == 0xFF)
        {
            i_Stream.Position = 2;
            return new UnicodeEncoding(true, true);
        }

        if (u8_Buf[0] == 0xFF && u8_Buf[1] == 0xFE)
        {
            if (s32_Count >= 4 && u8_Buf[2] == 0 && u8_Buf[3] == 0)
            {
                i_Stream.Position = 4;
                return new UTF32Encoding(false, true);
            }
            else
            {
                i_Stream.Position = 2;
                return new UnicodeEncoding(false, true);
            }
        }

        if (s32_Count >= 3 && u8_Buf[0] == 0xEF && u8_Buf[1] == 0xBB && u8_Buf[2] == 0xBF)
        {
            i_Stream.Position = 3;
            return Encoding.UTF8;
        }

        if (s32_Count >= 4 && u8_Buf[0] == 0 && u8_Buf[1] == 0 && u8_Buf[2] == 0xFE && u8_Buf[3] == 0xFF)
        {
            i_Stream.Position = 4;
            return new UTF32Encoding(true, true);
        }
    }

    i_Stream.Position = 0;
    return Encoding.Default;
}

fs: how do I locate a parent folder?

This works fine

path.join(__dirname + '/../client/index.html')
const path = require('path')
const fs = require('fs')
    fs.readFile(path.join(__dirname + '/../client/index.html'))

Query based on multiple where clauses in Firebase

I've written a personal library that allows you to order by multiple values, with all the ordering done on the server.

Meet Querybase!

Querybase takes in a Firebase Database Reference and an array of fields you wish to index on. When you create new records it will automatically handle the generation of keys that allow for multiple querying. The caveat is that it only supports straight equivalence (no less than or greater than).

const databaseRef = firebase.database().ref().child('people');
const querybaseRef = querybase.ref(databaseRef, ['name', 'age', 'location']);

// Automatically handles composite keys
querybaseRef.push({ 
  name: 'David',
  age: 27,
  location: 'SF'
});

// Find records by multiple fields
// returns a Firebase Database ref
const queriedDbRef = querybaseRef
 .where({
   name: 'David',
   age: 27
 });

// Listen for realtime updates
queriedDbRef.on('value', snap => console.log(snap));

Can't find System.Windows.Media namespace?

The System.Windows.Media.Imaging namespace is part of PresentationCore.dll (if you are using Visual Studio 2008 then the WPF application template will automatically add this reference). Note that this namespace is not a direct wrapping of the WIC library, although a large proportion of the more common uses are still available and it is relatively obvious how these map to the WIC versions. For more information on the classes in this namespace check out

http://msdn2.microsoft.com/en-us/library/system.windows.media.imaging.aspx

Print a file, skipping the first X lines, in Bash

Use the sed delete command with a range address. For example:

sed 1,100d file.txt # Print file.txt omitting lines 1-100.

Alternatively, if you want to only print a known range, use the print command with the -n flag:

sed -n 201,300p file.txt # Print lines 201-300 from file.txt

This solution should work reliably on all Unix systems, regardless of the presence of GNU utilities.

How to output JavaScript with PHP

You should escape the JavaScript string delimiters inside the PHP string. You're using double quotes for both PHP and JavaScript strings. Try like this instead:

<html>
<body>
<?php

// Here, we use single quotes for PHP and double quotes for JavaScript
echo '<script type="text/javascript">';
echo 'document.write("Hello World!")';
echo '</script>';

?>
</body>
</html>

You have to escape quotes on both JavaScript and PHP when the string delimiter are the same as the quotes:

echo "\""; // escape is done using a backslash
echo '\'';

Same in JavaScript:

alert("\""); // escape is done using a backslash
alert(echo '\'');

But because it's very hard to read a string with such escape sequences, it is better to combine single with double quotes, as needed:

echo '"';
echo "'";

How do I convert a Python program to a runnable .exe Windows program?

There is another way to convert Python scripts to .exe files. You can compile Python programs into C++ programs, which can be natively compiled just like any other C++ program.

Path to Powershell.exe (v 2.0)

I think $PsHome has the information you're after?

PS .> $PsHome
C:\Windows\System32\WindowsPowerShell\v1.0

PS .> Get-Help about_automatic_variables

TOPIC
    about_Automatic_Variables ...

Unable to find the wrapper "https" - did you forget to enable it when you configured PHP?

For those using Winginx (nginx based instead of Apache based), I fixed it with these 4 steps:

  1. On the Tools menu hit the Winginx PHP5 Config (never mind the 5 in the name...):

    Winginx PHP5 Config

  2. Select the PHP version you want the php.ini to change:

    PHP version selection

  3. On the PHP Extensions tab select the php_openssl extension and hit the Save button:

    php_openssl selection

  4. restart the appropriate PHP service through the taskbar (Stop and Start):

    Restart PHP service

R: invalid multibyte string

I figured out Leafpad to be an adequate and simple text-editor to view and save/convert in certain character sets - at least in the linux-world.

I used this to save the Latin-15 to UTF-8 and it worked.

Adding system header search path to Xcode

Follow up to Eonil's answer related to project level settings. With the target selected and the Build Settings tab selected, there may be no listing under Search Paths for Header Search Paths. In this case, you can change to "All" from "Basic" in the search bar and Header Search Paths will show up in the Search Paths section.

Reference — What does this symbol mean in PHP?

Nullable return type declaration

PHP 7 adds support for return type declarations. Similarly to argument type declarations, return type declarations specify the type of value that will be returned from a function. The same types are available for return type declarations as are available for argument type declarations.

Strict typing also has an effect on return type declarations. In the default weak mode, returned values will be coerced to the correct type if they are not already of that type. In strong mode, the returned value must be of the correct type, otherwise, a TypeError will be thrown.

As of PHP 7.1.0, return values can be marked as nullable by prefixing the type name with a question mark (?). This signifies that the function returns either the specified type or NULL.

<?php
function get_item(): ?string {
    if (isset($_GET['item'])) {
        return $_GET['item'];
    } else {
        return null;
    }
}
?>

Source

How to color System.out.println output?

Here is a solution for Win32 Console.

1) Get JavaNativeAccess libraries here: https://github.com/twall/jna/

2) These two Java classes will do the trick.

Enjoy.

package com.stackoverflow.util;

import com.sun.jna.Library;
import com.sun.jna.Native;
import com.sun.jna.Platform;
import com.sun.jna.Structure;

public class Win32 {
    public static final int STD_INPUT_HANDLE = -10;
    public static final int STD_OUTPUT_HANDLE = -11;
    public static final int STD_ERROR_HANDLE = -12;

    public static final short CONSOLE_FOREGROUND_COLOR_BLACK        = 0x00;
    public static final short CONSOLE_FOREGROUND_COLOR_BLUE         = 0x01;
    public static final short CONSOLE_FOREGROUND_COLOR_GREEN        = 0x02;
    public static final short CONSOLE_FOREGROUND_COLOR_AQUA         = 0x03;
    public static final short CONSOLE_FOREGROUND_COLOR_RED          = 0x04;
    public static final short CONSOLE_FOREGROUND_COLOR_PURPLE       = 0x05;
    public static final short CONSOLE_FOREGROUND_COLOR_YELLOW       = 0x06;
    public static final short CONSOLE_FOREGROUND_COLOR_WHITE        = 0x07;
    public static final short CONSOLE_FOREGROUND_COLOR_GRAY         = 0x08;
    public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_BLUE   = 0x09;
    public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_GREEN  = 0x0A;
    public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_AQUA   = 0x0B;
    public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_RED    = 0x0C;
    public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_PURPLE = 0x0D;
    public static final short CONSOLE_FOREGROUND_COLOR_LIGHT_YELLOW = 0x0E;
    public static final short CONSOLE_FOREGROUND_COLOR_BRIGHT_WHITE = 0x0F;

    public static final short CONSOLE_BACKGROUND_COLOR_BLACK        = 0x00;
    public static final short CONSOLE_BACKGROUND_COLOR_BLUE         = 0x10;
    public static final short CONSOLE_BACKGROUND_COLOR_GREEN        = 0x20;
    public static final short CONSOLE_BACKGROUND_COLOR_AQUA         = 0x30;
    public static final short CONSOLE_BACKGROUND_COLOR_RED          = 0x40;
    public static final short CONSOLE_BACKGROUND_COLOR_PURPLE       = 0x50;
    public static final short CONSOLE_BACKGROUND_COLOR_YELLOW       = 0x60;
    public static final short CONSOLE_BACKGROUND_COLOR_WHITE        = 0x70;
    public static final short CONSOLE_BACKGROUND_COLOR_GRAY         = 0x80;
    public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_BLUE   = 0x90;
    public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_GREEN  = 0xA0;
    public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_AQUA   = 0xB0;
    public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_RED    = 0xC0;
    public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_PURPLE = 0xD0;
    public static final short CONSOLE_BACKGROUND_COLOR_LIGHT_YELLOW = 0xE0;
    public static final short CONSOLE_BACKGROUND_COLOR_BRIGHT_WHITE = 0xF0;

    // typedef struct _COORD {
    //    SHORT X;
    //    SHORT Y;
    //  } COORD, *PCOORD;
    public static class COORD extends Structure {
        public short X;
        public short Y;
    }

    // typedef struct _SMALL_RECT {
    //    SHORT Left;
    //    SHORT Top;
    //    SHORT Right;
    //    SHORT Bottom;
    //  } SMALL_RECT;
    public static class SMALL_RECT extends Structure {
        public short Left;
        public short Top;
        public short Right;
        public short Bottom;
    }

    // typedef struct _CONSOLE_SCREEN_BUFFER_INFO {
    //    COORD      dwSize;
    //    COORD      dwCursorPosition;
    //    WORD       wAttributes;
    //    SMALL_RECT srWindow;
    //    COORD      dwMaximumWindowSize;
    //  } CONSOLE_SCREEN_BUFFER_INFO;
    public static class CONSOLE_SCREEN_BUFFER_INFO extends Structure {
        public COORD dwSize;
        public COORD dwCursorPosition;
        public short wAttributes;
        public SMALL_RECT srWindow;
        public COORD dwMaximumWindowSize;
    }

    // Source: https://github.com/twall/jna/nonav/javadoc/index.html
    public interface Kernel32 extends Library {
        Kernel32 DLL = (Kernel32) Native.loadLibrary("kernel32", Kernel32.class);

        // HANDLE WINAPI GetStdHandle(
        //        __in  DWORD nStdHandle
        //      );
        public int GetStdHandle(
                int nStdHandle);

        // BOOL WINAPI SetConsoleTextAttribute(
        //        __in  HANDLE hConsoleOutput,
        //        __in  WORD wAttributes
        //      );
        public boolean SetConsoleTextAttribute(
                int in_hConsoleOutput, 
                short in_wAttributes);

        // BOOL WINAPI GetConsoleScreenBufferInfo(
        //        __in   HANDLE hConsoleOutput,
        //        __out  PCONSOLE_SCREEN_BUFFER_INFO lpConsoleScreenBufferInfo
        //      );
        public boolean GetConsoleScreenBufferInfo(
                int in_hConsoleOutput,
                CONSOLE_SCREEN_BUFFER_INFO out_lpConsoleScreenBufferInfo);

        // DWORD WINAPI GetLastError(void);
        public int GetLastError();
    }
}
package com.stackoverflow.util;

import java.io.PrintStream;

import com.stackoverflow.util.Win32.Kernel32;

public class ConsoleUtil {
    public static void main(String[] args)
    throws Exception {
        System.out.print("abc");
        static_color_print(
                System.out, 
                "def", 
                Win32.CONSOLE_BACKGROUND_COLOR_RED, 
                Win32.CONSOLE_FOREGROUND_COLOR_BRIGHT_WHITE);
        System.out.print("def");
        System.out.println();
    }

    private static Win32.CONSOLE_SCREEN_BUFFER_INFO _static_console_screen_buffer_info = null; 

    public static void static_save_settings() {
        if (null == _static_console_screen_buffer_info) {
            _static_console_screen_buffer_info = new Win32.CONSOLE_SCREEN_BUFFER_INFO();
        }
        int stdout_handle = Kernel32.DLL.GetStdHandle(Win32.STD_OUTPUT_HANDLE);
        Kernel32.DLL.GetConsoleScreenBufferInfo(stdout_handle, _static_console_screen_buffer_info);
    }

    public static void static_restore_color()
    throws Exception {
        if (null == _static_console_screen_buffer_info) {
            throw new Exception("Internal error: Must save settings before restore");
        }
        int stdout_handle = Kernel32.DLL.GetStdHandle(Win32.STD_OUTPUT_HANDLE);
        Kernel32.DLL.SetConsoleTextAttribute(
                stdout_handle, 
                _static_console_screen_buffer_info.wAttributes);
    }

    public static void static_set_color(Short background_color, Short foreground_color) {
        int stdout_handle = Kernel32.DLL.GetStdHandle(Win32.STD_OUTPUT_HANDLE);
        if (null == background_color || null == foreground_color) {
            Win32.CONSOLE_SCREEN_BUFFER_INFO console_screen_buffer_info = 
                new Win32.CONSOLE_SCREEN_BUFFER_INFO();
            Kernel32.DLL.GetConsoleScreenBufferInfo(stdout_handle, console_screen_buffer_info);
            short current_bg_and_fg_color = console_screen_buffer_info.wAttributes;
            if (null == background_color) {
                short current_bg_color = (short) (current_bg_and_fg_color / 0x10);
                background_color = new Short(current_bg_color);
            }
            if (null == foreground_color) {
                short current_fg_color = (short) (current_bg_and_fg_color % 0x10);
                foreground_color = new Short(current_fg_color);
            }
        }
        short bg_and_fg_color = 
            (short) (background_color.shortValue() | foreground_color.shortValue());
        Kernel32.DLL.SetConsoleTextAttribute(stdout_handle, bg_and_fg_color);
    }

    public static<T> void static_color_print(
            PrintStream ostream, 
            T value, 
            Short background_color, 
            Short foreground_color)
    throws Exception {
        static_save_settings();
        try {
            static_set_color(background_color, foreground_color);
            ostream.print(value);
        }
        finally {
            static_restore_color();
        }
    }

    public static<T> void static_color_println(
            PrintStream ostream, 
            T value, 
            Short background_color, 
            Short foreground_color)
    throws Exception {
        static_save_settings();
        try {
            static_set_color(background_color, foreground_color);
            ostream.println(value);
        }
        finally {
            static_restore_color();
        }
    }
}

How to install a specific version of Node on Ubuntu?

NOTE: you can use NVM software to do this in a more nodejs fashionway. However i got issues in one machine that didn't let me use NVM. So i have to look for an alternative ;-)

You can manually download and install.

go to nodejs > download > other releases http://nodejs.org/dist/

choose the version you are looking for http://nodejs.org/dist/v0.8.18/

choose distro files corresponding your environmment and download (take care of 32bits/64bits version). Example: http://nodejs.org/dist/v0.8.18/node-v0.8.18-linux-x64.tar.gz

Extract files and follow instructions on README.md :

To build:

Prerequisites (Unix only):

* Python 2.6 or 2.7
* GNU Make 3.81 or newer
* libexecinfo (FreeBSD and OpenBSD only)

Unix/Macintosh:

./configure
make
make install

If your python binary is in a non-standard location or has a non-standard name, run the following instead:

export PYTHON=/path/to/python
$PYTHON ./configure
make
make install

Windows:

vcbuild.bat

To run the tests:

Unix/Macintosh:

make test

Windows:

vcbuild.bat test

To build the documentation:

make doc

To read the documentation:

man doc/node.1

Maybe you want to (must to) move the folder to a more apropiate place like /usr/lib/nodejs/node-v0.8.18/ then create a Symbolic Lynk on /usr/bin to get acces to your install from anywhere.

sudo mv /extracted/folder/node-v0.8.18 /usr/lib/nodejs/node-v0.8.18
sudo ln -s /usr/lib/nodejs/node-v0.8.18/bin/node /usr/bin/node

And if you want different release in the same machine you can use debian alternatives. Proceed in the same way posted before to download a second release. For example the latest release.

http://nodejs.org/dist/latest/ -> http://nodejs.org/dist/latest/node-v0.10.28-linux-x64.tar.gz

Move to your favorite destination, the same of the rest of release you want to install.

sudo mv /extracted/folder/node-v0.10.28 /usr/lib/nodejs/node-v0.10.28

Follow instructions of the README.md file. Then update the alternatives, for each release you have dowload install the alternative with.

sudo update-alternatives    --install genname symlink  altern  priority  [--slave  genname  symlink altern]
          Add a group of alternatives  to  the  system.   genname  is  the
          generic  name  for  the  master link, symlink is the name of its
          symlink  in  the  alternatives  directory,  and  altern  is  the
          alternative being introduced for the master link.  The arguments
          after  --slave  are  the  generic  name,  symlink  name  in  the
          alternatives  directory  and alternative for a slave link.  Zero
          or more --slave options, each followed by three  arguments,  may
          be specified.

          If   the   master   symlink  specified  exists  already  in  the
          alternatives system’s records, the information supplied will  be
          added  as a new set of alternatives for the group.  Otherwise, a
          new group, set to  automatic  mode,  will  be  added  with  this
          information.   If  the group is in automatic mode, and the newly
          added alternatives’ priority is higher than any other  installed
          alternatives  for  this  group,  the symlinks will be updated to
          point to the newly added alternatives.

for example:

sudo update-alternatives --install /usr/bin/node node /usr/lib/nodejs/node-v0.10.28 0 --slave /usr/share/man/man1/node.1.gz node.1.gz /usr/lib/nodejs/node-v0.10.28/share/man/man1/node.1

Then you can use update-alternatives --config node to choose between any number of releases instaled in your machine.

How to generate a unique hash code for string input in android...?

Let's take a look at the stock hashCode() method:

public int hashCode() {
    int h = hash;
    if (h == 0 && count > 0) {
        for (int i = 0; i < count; i++) {
            h = 31 * h + charAt(i);
        }
        hash = h;
    }
    return h;
}

The block of code above comes from the java.lang.String class. As you can see it is a 32 bit hash code which fair enough if you are using it on a small scale of data. If you are looking for hash code with more than 32 bit, you might wanna checkout this link: http://www.javamex.com/tutorials/collections/strong_hash_code_implementation.shtml

How to handle command-line arguments in PowerShell

You are reinventing the wheel. Normal PowerShell scripts have parameters starting with -, like script.ps1 -server http://devserver

Then you handle them in param section in the beginning of the file.

You can also assign default values to your params, read them from console if not available or stop script execution:

 param (
    [string]$server = "http://defaultserver",
    [Parameter(Mandatory=$true)][string]$username,
    [string]$password = $( Read-Host "Input password, please" )
 )

Inside the script you can simply

write-output $server

since all parameters become variables available in script scope.

In this example, the $server gets a default value if the script is called without it, script stops if you omit the -username parameter and asks for terminal input if -password is omitted.

Update: You might also want to pass a "flag" (a boolean true/false parameter) to a PowerShell script. For instance, your script may accept a "force" where the script runs in a more careful mode when force is not used.

The keyword for that is [switch] parameter type:

 param (
    [string]$server = "http://defaultserver",
    [string]$password = $( Read-Host "Input password, please" ),
    [switch]$force = $false
 )

Inside the script then you would work with it like this:

if ($force) {
  //deletes a file or does something "bad"
}

Now, when calling the script you'd set the switch/flag parameter like this:

.\yourscript.ps1 -server "http://otherserver" -force

If you explicitly want to state that the flag is not set, there is a special syntax for that

.\yourscript.ps1 -server "http://otherserver" -force:$false

Links to relevant Microsoft documentation (for PowerShell 5.0; tho versions 3.0 and 4.0 are also available at the links):

How to make the background DIV only transparent using CSS

<div id="divmobile" style="position: fixed; background-color: transparent;
    z-index: 1; bottom:5%; right: 0px; width: 50px; text-align:center;" class="div-mobile">

Including one C source file in another?

You can use the gcc compiler in linux to link two c file in one output. Suppose you have two c files one is 'main.c' and another is 'support.c'. So the command to link these two is

gcc main.c support.c -o main.out

By this two files will be linked to a single output main.out To run the output the command will be

./main.out

If you are using function in main.c which is declared in support.c file then you should declare it in main also using extern storage class.

How to get Enum Value from index in Java?

I recently had the same problem and used the solution provided by Harry Joy. That solution only works with with zero-based enumaration though. I also wouldn't consider it save as it doesn't deal with indexes that are out of range.

The solution I ended up using might not be as simple but it's completely save and won't hurt the performance of your code even with big enums:

public enum Example {

    UNKNOWN(0, "unknown"), ENUM1(1, "enum1"), ENUM2(2, "enum2"), ENUM3(3, "enum3");

    private static HashMap<Integer, Example> enumById = new HashMap<>();
    static {
        Arrays.stream(values()).forEach(e -> enumById.put(e.getId(), e));
    }

    public static Example getById(int id) {
        return enumById.getOrDefault(id, UNKNOWN);
    }

    private int id;
    private String description;

    private Example(int id, String description) {
        this.id = id;
        this.description= description;
    }

    public String getDescription() {
        return description;
    }

    public int getId() {
        return id;
    }
}

If you are sure that you will never be out of range with your index and you don't want to use UNKNOWN like I did above you can of course also do:

public static Example getById(int id) {
        return enumById.get(id);
}

jQuery SVG vs. Raphael

I'm a huge fan of Raphael and the development momentum seems to be going strong (version 0.85 was released late last week). Another big plus is that its developer, Dmitry Baranovskiy, is currently working on a Raphael charting plugin, g.raphael, which looks like its shaping up to be pretty slick (there are a few samples of the output from the early versions on Flickr).

However, just to throw another possible contender into the SVG library mix, Google's SVG Web looks very promising indeed (even though I'm not a big fan of Flash, which it uses to render in non-SVG compliant browsers). Probably one to watch, especially with the upcoming SVG Open conference.

I get Access Forbidden (Error 403) when setting up new alias

try this

sudo chmod -R 0777 /opt/lampp/htdocs/testproject

Rounding to 2 decimal places in SQL

Try this...

SELECT TO_CHAR(column_name,'99G999D99MI')
as format_column
FROM DUAL;

Set Focus After Last Character in Text Box

<script type="text/javascript">
    $(function(){
        $('#areaCode,#firstNum,#secNum').keyup(function(e){
            if($(this).val().length==$(this).attr('maxlength'))
                $(this).next(':input').focus()
        })
    })
    </script>

<body>

<input type="text" id="areaCode" name="areaCode" maxlength="3" value="" size="3" />- 
<input type="text" id="firstNum" name="firstNum" maxlength="3" value="" size="3" />- 
<input type="text" id="secNum" name=" secNum " maxlength="4" value="" size="4" />

</body>

Clear dropdown using jQuery Select2

Since none of them all worked for me (select2 4.0.3) is went the std select way.

for(var i = selectbox.options.length - 1 ; i >= 0 ; i--)
    selectbox.remove(i);

check if directory exists and delete in one command unix

Assuming $WORKING_DIR is set to the directory... this one-liner should do it:

if [ -d "$WORKING_DIR" ]; then rm -Rf $WORKING_DIR; fi

(otherwise just replace with your directory)

Disable form auto submit on button click

Buttons like <button>Click to do something</button> are submit buttons.

Set type="button" to change that. type="submit" is the default (as specified by the HTML recommendation).

Using underscores in Java variables and method names

Rules:

  1. Do what the code you are editing does
  2. If #1 doesn't apply, use camelCase, no underscores

Submit form without page reloading

Have you tried using an iFrame? No ajax, and the original page will not load.

You can display the submit form as a separate page inside the iframe, and when it gets submitted the outer/container page will not reload. This solution will not make use of any kind of ajax.

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

Remove the onchange event from the HTML Markup and bind it in your document ready event

<select  name="a[b]" >
     <option value='Choice 1'>Choice 1</option>
     <option value='Choice 2'>Choice 2</option>
</select>?

and Script

$(function(){    
    $("select[name='a[b]']").change(function(){
       alert($(this).val());        
    }); 
});

Working sample : http://jsfiddle.net/gLaR8/3/

Check whether an input string contains a number in javascript

This code also helps in, "To Detect Numbers in Given String" when numbers found it stops its execution.

function hasDigitFind(_str_) {
  this._code_ = 10;  /*When empty string found*/
  var _strArray = [];

  if (_str_ !== '' || _str_ !== undefined || _str_ !== null) {
    _strArray = _str_.split('');
    for(var i = 0; i < _strArray.length; i++) {
      if(!isNaN(parseInt(_strArray[i]))) {
        this._code_ = -1;
        break;
      } else {
        this._code_ = 1;
      }
    }

  }
  return this._code_;
}

How can I make a SQL temp table with primary key and auto-incrementing field?

You are just missing the words "primary key" as far as I can see to meet your specified objective.

For your other columns it's best to explicitly define whether they should be NULL or NOT NULL though so you are not relying on the ANSI_NULL_DFLT_ON setting.

CREATE TABLE #tmp
(
ID INT IDENTITY(1, 1) primary key ,
AssignedTo NVARCHAR(100),
AltBusinessSeverity NVARCHAR(100),
DefectCount int
);

insert into #tmp 
select 'user','high',5 union all
select 'user','med',4


select * from #tmp

How to add a button dynamically in Android?

You could create a base layout for your button and dynamically change only what is specific, like this project I made to run different exercises from a Material Design course I'm taking:

In this example, I use a preconfigured AppCompatButton:

layout_base_button.xml

<android.support.v7.widget.AppCompatButton
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/btn_base"
    android:layout_width="200dp"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:layout_marginTop="8dp"
    style="@style/RaisedButton"
    >

</android.support.v7.widget.AppCompatButton>


<style name="RaisedButton" parent="Widget.AppCompat.Button.Colored">
    <item name="android:textSize">11sp</item>
    <item name="android:textStyle">bold</item>
</style>

And in the MainActivity I created some instances and changed what I need, like the button text and onClick event:

<ScrollView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="udemy.android.materialdesign.MainActivity">

    <LinearLayout
        android:id="@+id/base_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        >

    </LinearLayout>


</ScrollView>



public class MainActivity extends AppCompatActivity {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        LinearLayout baseLayout = findViewById(R.id.base_layout);

        baseLayout.addView(createButton("TextFields", baseLayout,
                view -> startActivity(createIntent(TextFieldsActivity.class))
        ));

        baseLayout.addView(createButton("Buttons", baseLayout,
                view -> startActivity(createIntent(ButtonsActivity.class))
        ));

        baseLayout.addView(createButton("Toolbar", baseLayout,
                view -> startActivity(createIntent(ToolbarActivity.class))
        ));

    }

    private View createButton(String text, LinearLayout baseLayout, View.OnClickListener onClickEvent) {
        View inflated = LayoutInflater.from(this).inflate(R.layout.layout_base_button, baseLayout, false);
        AppCompatButton btnBase = inflated.findViewById(R.id.btn_base);

        btnBase.setText(text);
        btnBase.setOnClickListener(onClickEvent);
        return btnBase;
    }

    private Intent createIntent(Class<?> cls) {
        return new Intent(this, cls);
    }
}

Sorry for being late...

Why would one omit the close tag?

"Is there another good reason (other than the header problem) to skip the ending php tag?"

You don't want to inadvertently output extraneous whitepace characters when generating binary output, CSV data, or other non-HTML output.

Load RSA public key from file

This program is doing almost everything with Public and private keys. The der format can be obtained but saving raw data ( without encoding base64). I hope this helps programmers.

import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.SignatureException;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import sun.security.pkcs.PKCS8Key;
import sun.security.pkcs10.PKCS10;
import sun.security.x509.X500Name;

import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;



/**
 * @author Desphilboy
 * DorOd bar shomA barobach
 *
 */
public class csrgenerator {

    private static PublicKey publickey= null;
    private static PrivateKey privateKey=null;
    //private static PKCS8Key privateKey=null;
    private static KeyPairGenerator kpg= null;
    private static ByteArrayOutputStream bs =null;
    private static csrgenerator thisinstance;
    private KeyPair keypair;
    private static PKCS10 pkcs10;
    private String signaturealgorithm= "MD5WithRSA";

    public String getSignaturealgorithm() {
        return signaturealgorithm;
    }



    public void setSignaturealgorithm(String signaturealgorithm) {
        this.signaturealgorithm = signaturealgorithm;
    }



    private csrgenerator() {
        try {
           kpg = KeyPairGenerator.getInstance("RSA");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            System.out.print("No such algorithm RSA in constructor csrgenerator\n");
        }
        kpg.initialize(2048);
        keypair = kpg.generateKeyPair();
        publickey = keypair.getPublic();
        privateKey = keypair.getPrivate();
    }



    /** Generates a new key pair 
    *
    * @param int bits 
    *   this is the number of bits in modulus must be 512, 1024, 2048  or so on 
    */
    public KeyPair generateRSAkys(int bits)
    {
          kpg.initialize(bits);
            keypair = kpg.generateKeyPair();
            publickey = keypair.getPublic();
            privateKey = keypair.getPrivate();
            KeyPair dup= keypair;
     return dup;
    }

     public static csrgenerator getInstance() {
            if (thisinstance == null)
                thisinstance = new csrgenerator();
            return thisinstance;
        }


     /**
      *  Returns a CSR as string  
      * @param cn  Common Name
      * @param OU  Organizational Unit 
      * @param Org  Organization
      * @param LocName Location name
      * @param Statename  State/Territory/Province/Region
      * @param Country    Country
      * @return     returns  csr as string.
      * @throws Exception
      */
     public String getCSR(String commonname, String organizationunit, String organization,String localname, String statename, String country ) throws Exception {
            byte[] csr = generatePKCS10(commonname, organizationunit, organization, localname, statename, country,signaturealgorithm);
            return new String(csr);
        }

     /** This function generates a new Certificate 
      * Signing Request. 
     *
     * @param CN
     *            Common Name, is X.509 speak for the name that distinguishes
     *            the Certificate best, and ties it to your Organization
     * @param OU
     *            Organizational unit
     * @param O
     *            Organization NAME
     * @param L
     *            Location
     * @param S
     *            State
     * @param C
     *            Country
     * @return    byte stream of generated request
     * @throws Exception
     */
    private static byte[] generatePKCS10(String CN, String OU, String O,String L, String S, String C,String sigAlg) throws Exception {
        // generate PKCS10 certificate request

        pkcs10 = new PKCS10(publickey);
       Signature   signature = Signature.getInstance(sigAlg);
        signature.initSign(privateKey);
        // common, orgUnit, org, locality, state, country
        //X500Name(String commonName, String organizationUnit,String organizationName,Local,State, String country)
        X500Name x500Name = new X500Name(CN, OU, O, L, S, C);
        pkcs10.encodeAndSign(x500Name,signature);
        bs = new ByteArrayOutputStream();
        PrintStream ps = new PrintStream(bs);
        pkcs10.print(ps);
        byte[] c = bs.toByteArray();
        try {
            if (ps != null)
                ps.close();
            if (bs != null)
                bs.close();
        } catch (Throwable th) {
        }
        return c;
    }

    public  PublicKey getPublicKey() {
        return publickey;
    }




    /**
     * @return
     */
    public PrivateKey getPrivateKey() {
        return privateKey;
    }

    /**
     * saves private key to a file
     * @param filename
     */
    public  void SavePrivateKey(String filename)
    {
        PKCS8EncodedKeySpec pemcontents=null;
        pemcontents= new PKCS8EncodedKeySpec( privateKey.getEncoded());
        PKCS8Key pemprivatekey= new  PKCS8Key( );
        try {
            pemprivatekey.decode(pemcontents.getEncoded());
        } catch (InvalidKeyException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        File file=new File(filename);
        try {

            file.createNewFile();
            FileOutputStream fos=new FileOutputStream(file);
            fos.write(pemprivatekey.getEncoded());
            fos.flush();
            fos.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }



    }



    /**
     * Saves Certificate Signing Request to a file;
     * @param filename  is a String containing full path to the file which will be created containing the CSR.
     */
    public void SaveCSR(String filename)
    {
        FileOutputStream fos=null;
        PrintStream ps=null;
        File file;
        try {

            file = new File(filename);
            file.createNewFile();
            fos = new FileOutputStream(file);
            ps= new PrintStream(fos);
        }catch (IOException e)
        {
            System.out.print("\n could not open the file "+ filename);
        }

        try {
            try {
                pkcs10.print(ps);
            } catch (SignatureException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            ps.flush();
            ps.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            System.out.print("\n cannot write to the file "+ filename);
            e.printStackTrace();

        }

        }


    /**
     * Saves both public key and private  key to file names specified
     * @param fnpub  file name of public key
     * @param fnpri  file name of private key
     * @throws IOException
     */
    public static void SaveKeyPair(String fnpub,String fnpri) throws IOException { 

// Store Public Key.
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(
publickey.getEncoded());
FileOutputStream fos = new FileOutputStream(fnpub);
fos.write(x509EncodedKeySpec.getEncoded());
fos.close();

// Store Private Key.
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(privateKey.getEncoded());
fos = new FileOutputStream(fnpri);
fos.write(pkcs8EncodedKeySpec.getEncoded());
fos.close();
}


    /**
     * Reads a Private Key from a pem base64 encoded file.
     * @param filename name of the file to read.
     * @param algorithm Algorithm is usually "RSA"
     * @return returns the privatekey which is read from the file;
     * @throws Exception
     */
    public  PrivateKey getPemPrivateKey(String filename, String algorithm) throws Exception {
          File f = new File(filename);
          FileInputStream fis = new FileInputStream(f);
          DataInputStream dis = new DataInputStream(fis);
          byte[] keyBytes = new byte[(int) f.length()];
          dis.readFully(keyBytes);
          dis.close();

          String temp = new String(keyBytes);
          String privKeyPEM = temp.replace("-----BEGIN PRIVATE KEY-----", "");
          privKeyPEM = privKeyPEM.replace("-----END PRIVATE KEY-----", "");
          //System.out.println("Private key\n"+privKeyPEM);

          BASE64Decoder b64=new BASE64Decoder();
          byte[] decoded = b64.decodeBuffer(privKeyPEM);

          PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(decoded);
          KeyFactory kf = KeyFactory.getInstance(algorithm);
          return kf.generatePrivate(spec);
          }



    /**
     * Saves the private key to a pem file.
     * @param filename  name of the file to write the key into 
     * @param key the Private key to save.
     * @return  String representation of the pkcs8 object.
     * @throws Exception
     */
    public  String  SavePemPrivateKey(String filename) throws Exception {
        PrivateKey key=this.privateKey;
          File f = new File(filename);
          FileOutputStream fos = new FileOutputStream(f);
          DataOutputStream dos = new DataOutputStream(fos);


          byte[] keyBytes = key.getEncoded();
          PKCS8Key pkcs8= new PKCS8Key();
          pkcs8.decode(keyBytes);
          byte[] b=pkcs8.encode();

          BASE64Encoder b64=new BASE64Encoder();
          String  encoded = b64.encodeBuffer(b);

          encoded= "-----BEGIN PRIVATE KEY-----\r\n" + encoded + "-----END PRIVATE KEY-----";

         dos.writeBytes(encoded);
         dos.flush();
         dos.close();

          //System.out.println("Private key\n"+privKeyPEM);
        return pkcs8.toString();

          }


    /**
     * Saves a public key to a base64 encoded pem file
     * @param filename  name of the file 
     * @param key public key to be saved 
     * @return string representation of the pkcs8 object.
     * @throws Exception
     */
    public  String  SavePemPublicKey(String filename) throws Exception {
        PublicKey key=this.publickey;  
        File f = new File(filename);
          FileOutputStream fos = new FileOutputStream(f);
          DataOutputStream dos = new DataOutputStream(fos);


          byte[] keyBytes = key.getEncoded();
          BASE64Encoder b64=new BASE64Encoder();
          String  encoded = b64.encodeBuffer(keyBytes);

          encoded= "-----BEGIN PUBLIC KEY-----\r\n" + encoded + "-----END PUBLIC KEY-----";

         dos.writeBytes(encoded);
         dos.flush();
         dos.close();

          //System.out.println("Private key\n"+privKeyPEM);
      return  encoded.toString();

          }





       /**
     * reads a public key from a file
     * @param filename name of the file to read
     * @param algorithm is usually RSA
     * @return the read public key
     * @throws Exception
     */
    public  PublicKey getPemPublicKey(String filename, String algorithm) throws Exception {
          File f = new File(filename);
          FileInputStream fis = new FileInputStream(f);
          DataInputStream dis = new DataInputStream(fis);
          byte[] keyBytes = new byte[(int) f.length()];
          dis.readFully(keyBytes);
          dis.close();

          String temp = new String(keyBytes);
          String publicKeyPEM = temp.replace("-----BEGIN PUBLIC KEY-----\n", "");
          publicKeyPEM = publicKeyPEM.replace("-----END PUBLIC KEY-----", "");


          BASE64Decoder b64=new BASE64Decoder();
          byte[] decoded = b64.decodeBuffer(publicKeyPEM);

          X509EncodedKeySpec spec =
                new X509EncodedKeySpec(decoded);
          KeyFactory kf = KeyFactory.getInstance(algorithm);
          return kf.generatePublic(spec);
          }




    public static void main(String[] args) throws Exception {
        csrgenerator gcsr = csrgenerator.getInstance();
        gcsr.setSignaturealgorithm("SHA512WithRSA");
        System.out.println("Public Key:\n"+gcsr.getPublicKey().toString());

        System.out.println("Private Key:\nAlgorithm: "+gcsr.getPrivateKey().getAlgorithm().toString());
        System.out.println("Format:"+gcsr.getPrivateKey().getFormat().toString());
        System.out.println("To String :"+gcsr.getPrivateKey().toString());
        System.out.println("GetEncoded :"+gcsr.getPrivateKey().getEncoded().toString());
        BASE64Encoder encoder= new BASE64Encoder();
        String s=encoder.encodeBuffer(gcsr.getPrivateKey().getEncoded());
        System.out.println("Base64:"+s+"\n");

        String csr = gcsr.getCSR( "[email protected]","baxshi az xodam", "Xodam","PointCook","VIC" ,"AU");
        System.out.println("CSR Request Generated!!");
        System.out.println(csr);
        gcsr.SaveCSR("c:\\testdir\\javacsr.csr");
        String p=gcsr.SavePemPrivateKey("c:\\testdir\\java_private.pem");
        System.out.print(p);
        p=gcsr.SavePemPublicKey("c:\\testdir\\java_public.pem");
        privateKey= gcsr.getPemPrivateKey("c:\\testdir\\java_private.pem", "RSA");
        BASE64Encoder encoder1= new BASE64Encoder();
        String s1=encoder1.encodeBuffer(gcsr.getPrivateKey().getEncoded());
        System.out.println("Private Key in Base64:"+s1+"\n");
        System.out.print(p);


    }

    }

You have not concluded your merge (MERGE_HEAD exists)

I resolved the conflict and then do a commit with -a option. It worked for me.

How can I get the values of data attributes in JavaScript code?

Circa 2019, using jquery, this can be accessed using $('#DOMId').data('typeId') where $('#DOMId') is the jquery selector for your span element.

How to stretch div height to fill parent div - CSS

http://jsfiddle.net/QWDxr/1/

Use the "min-height" property
Be wary of paddings, margins and borders :)

html, body {
    margin: 0;
    padding: 0;
    border: 0;
}
#B, #C, #D {
    position: absolute;
}
#A{
    top: 0;
    width: 100%;
    height: 35px;
    background-color: #99CC00;
}
#B {
    top: 35px;
    width: 200px;
    bottom: 35px;
    background-color: #999999;
    z-index:100;
}
#B2 {
    min-height: 100%;
    height: 100%;
    margin-top: -35px;
    bottom: 0;
    background-color: red;
    width: 200px;
    overflow: scroll;
}
#B1 {
    height: 35px;
    width: 35px;
    margin-left: 200px;
    background-color: #CC0066;
}
#C {
    top: 35px;
    left: 200px;
    right: 0;
    bottom: 35px;
    background-color: #CCCCCC;
}
#D {
    bottom: 0;
    width: 100%;
    height: 35px;
    background-color: #3399FF;
}

How to initialize a private static const map in C++?

If you are using a compiler which still doesn't support universal initialization or you have reservation in using Boost, another possible alternative would be as follows

std::map<int, int> m = [] () {
    std::pair<int,int> _m[] = {
        std::make_pair(1 , sizeof(2)),
        std::make_pair(3 , sizeof(4)),
        std::make_pair(5 , sizeof(6))};
    std::map<int, int> m;
    for (auto data: _m)
    {
        m[data.first] = data.second;
    }
    return m;
}();

How do I run a file on localhost?

Localhost is the computer you're using right now. You run things by typing commands at the command prompt and pressing Enter. If you're asking how to run things from your programming environment, then the answer depends on which environment you're using. Most languages have commands with names like system or exec for running external programs. You need to be more specific about what you're actually looking to do, and what obstacles you've encountered while trying to achieve it.

When to use Hadoop, HBase, Hive and Pig?

Hadoop:

HDFS stands for Hadoop Distributed File System which uses Computational processing model Map-Reduce.

HBase:

HBase is Key-Value storage, good for reading and writing in near real time.

Hive:

Hive is used for data extraction from the HDFS using SQL-like syntax. Hive use HQL language.

Pig:

Pig is a data flow language for creating ETL. It's an scripting language.

How to import a bak file into SQL Server Express

To do this via TSQL (ssms query window or sqlcmd.exe) just run:

RESTORE DATABASE MyDatabase FROM DISK='c:\backups\MyDataBase1.bak'

To do it via GUI - open SSMS, right click on Databases and follow the steps below

enter image description here enter image description here

Mysql password expired. Can't connect

All of these answers are using Linux consoles to access MySQL.

If you are on Windows and are using WAMP, you can start by opening the MySQL console (click WAMP icon->MySQL->MySQL console).

Then it will request you to enter your current password, enter it.

And then type SET PASSWORD = PASSWORD('some_pass');

Visual Studio: How to break on handled exceptions?

Check Managing Exceptions with the Debugger page, it explains how to set this up.

Essentially, here are the steps (during debugging):

  1. On the Debug menu, click Exceptions.

  2. In the Exceptions dialog box, select Thrown for an entire category of exceptions, for example, Common Language Runtime Exceptions.

    -or-

    Expand the node for a category of exceptions, for example, Common Language Runtime Exceptions, and select Thrown for a specific exception within that category.

How to loop over a Class attributes in Java?

Simple way to iterate over class fields and obtain values from object:

 Class<?> c = obj.getClass();
 Field[] fields = c.getDeclaredFields();
 Map<String, Object> temp = new HashMap<String, Object>();

 for( Field field : fields ){
      try {
           temp.put(field.getName().toString(), field.get(obj));
      } catch (IllegalArgumentException e1) {
      } catch (IllegalAccessException e1) {
      }
 }

open read and close a file in 1 line of code

I frequently do something like this when I need to get a few lines surrounding something I've grepped in a log file:

$ grep -n "xlrd" requirements.txt | awk -F ":" '{print $1}'
54

$ python -c "with open('requirements.txt') as file: print ''.join(file.readlines()[52:55])"
wsgiref==0.1.2
xlrd==0.9.2
xlwt==0.7.5

How to POST JSON Data With PHP cURL?

Try like this:

$url = 'url_to_post';
// this is only part of the data you need to sen
$customer_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" ) );
// As per your API, the customer data should be structured this way
$data = array("customer" => $customer_data);
// And then encoded as a json string
$data_string = json_encode($data);
$ch=curl_init($url);

curl_setopt_array($ch, array(
    CURLOPT_POST => true,
    CURLOPT_POSTFIELDS => $data_string,
    CURLOPT_HEADER => true,
    CURLOPT_HTTPHEADER => array('Content-Type:application/json', 'Content-Length: ' . strlen($data_string)))
));

$result = curl_exec($ch);
curl_close($ch);

The key thing you've forgotten was to json_encode your data. But you also may find it convenient to use curl_setopt_array to set all curl options at once by passing an array.

How can I create a copy of an Oracle table without copying the data?

Using pl/sql developer you can right click on the table_name either in the sql workspace or in the object explorer, than click on "view" and than click "view sql" which generates the sql script to create the table along with all the constraints, indexes, partitions etc..

Next you run the script using the new_table_name

Android, Java: HTTP POST Request

I'd rather recommend you to use Volley to make GET, PUT, POST... requests.

First, add dependency in your gradle file.

compile 'com.he5ed.lib:volley:android-cts-5.1_r4'

Now, use this code snippet to make requests.

RequestQueue queue = Volley.newRequestQueue(getApplicationContext());

        StringRequest postRequest = new StringRequest( com.android.volley.Request.Method.POST, mURL,
                new Response.Listener<String>()
                {
                    @Override
                    public void onResponse(String response) {
                        // response
                        Log.d("Response", response);
                    }
                },
                new Response.ErrorListener()
                {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        // error
                        Log.d("Error.Response", error.toString());
                    }
                }
        ) {
            @Override
            protected Map<String, String> getParams()
            {
                Map<String, String>  params = new HashMap<String, String>();
                //add your parameters here as key-value pairs
                params.put("username", username);
                params.put("password", password);

                return params;
            }
        };
        queue.add(postRequest);

Assign format of DateTime with data annotations?

If your data field is already a DateTime datatype, you don't need to use [DataType(DataType.Date)] for the annotation; just use:

[DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:MM/dd/yyyy}")]

on the jQuery, use datepicker for you calendar

    $(document).ready(function () {
        $('#StartDate').datepicker();
    });

on your HTML, use EditorFor helper:

    @Html.EditorFor(model => model.StartDate)

Negative list index?

List indexes of -x mean the xth item from the end of the list, so n[-1] means the last item in the list n. Any good Python tutorial should have told you this.

It's an unusual convention that only a few other languages besides Python have adopted, but it is extraordinarily useful; in any other language you'll spend a lot of time writing n[n.length-1] to access the last item of a list.

How can I check Drupal log files?

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

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

error_reporting(E_ALL);

ini_set('display_errors', TRUE); 

ini_set('display_startup_errors', TRUE); 

in index.php at top.;

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

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

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

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

JQuery/Javascript: check if var exists

You can use typeof:

if (typeof pagetype === 'undefined') {
    // pagetype doesn't exist
}

Creating a copy of an object in C#

There is no built-in way. You can have MyClass implement the IClonable interface (but it is sort of deprecated) or just write your own Copy/Clone method. In either case you will have to write some code.

For big objects you could consider Serialization + Deserialization (through a MemoryStream), just to reuse existing code.

Whatever the method, think carefully about what "a copy" means exactly. How deep should it go, are there Id fields to be excepted etc.

Json.NET serialize object with root name

Sorry, my english is not that good. But i like to improve the upvoted answers. I think that using Dictionary is more simple and clean.

class Program
    {
        static void Main(string[] args)
        {
            agencia ag1 = new agencia()
            {
                name = "Iquique",
                data = new object[] { new object[] {"Lucas", 20 }, new object[] {"Fernando", 15 } }
            };
            agencia ag2 = new agencia()
            {
                name = "Valparaiso",
                data = new object[] { new object[] { "Rems", 20 }, new object[] { "Perex", 15 } }
            };
            agencia agn = new agencia()
            {
                name = "Santiago",
                data = new object[] { new object[] { "Jhon", 20 }, new object[] { "Karma", 15 } }
            };


            Dictionary<string, agencia> dic = new Dictionary<string, agencia>
            {
                { "Iquique", ag1 },
                { "Valparaiso", ag2 },
                { "Santiago", agn }
            };

            string da = Newtonsoft.Json.JsonConvert.SerializeObject(dic);

            Console.WriteLine(da);
            Console.ReadLine();
        }


    }

    public class agencia
    {
        public string name { get; set; }
        public object[] data { get; set; }
    }

This code generate the following json (This is desired format)

{  
   "Iquique":{  
      "name":"Iquique",
      "data":[  
         [  
            "Lucas",
            20
         ],
         [  
            "Fernando",
            15
         ]
      ]
   },
   "Valparaiso":{  
      "name":"Valparaiso",
      "data":[  
         [  
            "Rems",
            20
         ],
         [  
            "Perex",
            15
         ]
      ]
   },
   "Santiago":{  
      "name":"Santiago",
      "data":[  
         [  
            "Jhon",
            20
         ],
         [  
            "Karma",
            15
         ]
      ]
   }
}

MySQLDump one INSERT statement for each data row

Use:

mysqldump --extended-insert=FALSE 

Be aware that multiple inserts will be slower than one big insert.

Replace multiple strings at once

The top answer is equivalent to doing:

let text = find.reduce((acc, item, i) => {
  const regex = new RegExp(item, "g");
  return acc.replace(regex, replace[i]);
}, textarea);

Given this:

var textarea = $(this).val();
var find = ["<", ">", "\n"];
var replace = ["&lt;", "&gt;", "<br/>"];

In this case, no imperative programming is going on.

Any free WPF themes?

Not purely themes, but MahApps.Metro provides Windows 8 Look and feel with a few variants like dark and light base themes with green,blue etc for text and others. Its pretty cool and can be used out of the box.

Execute Python script via crontab

As you have mentioned it doesn't change anything.

First, you should redirect both standard input and standard error from the crontab execution like below:

*/2 * * * * /usr/bin/python /home/souza/Documets/Listener/listener.py > /tmp/listener.log 2>&1

Then you can view the file /tmp/listener.log to see if the script executed as you expected.

Second, I guess what you mean by change anything is by watching the files created by your program:

f = file('counter', 'r+w')
json_file = file('json_file_create_server.json', 'r+w')

The crontab job above won't create these file in directory /home/souza/Documets/Listener, as the cron job is not executed in this directory, and you use relative path in the program. So to create this file in directory /home/souza/Documets/Listener, the following cron job will do the trick:

*/2 * * * * cd /home/souza/Documets/Listener && /usr/bin/python listener.py > /tmp/listener.log 2>&1

Change to the working directory and execute the script from there, and then you can view the files created in place.

Convert xlsx to csv in Linux with command line

In bash, I used this libreoffice command to convert all my xlsx files in the current directory:

for i   in *.xlsx; do  libreoffice --headless --convert-to csv "$i" ; done

It takes care of spaces in the filename.

Tried again some years later, and it didn't work. This thread gives some tips, but the quickiest solution was to run as root (or running a sudo libreoffice). Not elegant, but quick.

Use the command scalc.exe in Windows

What are the RGB codes for the Conditional Formatting 'Styles' in Excel?

For 'Bad' red:

  • The Font Is: (156,0,6)
  • The Background Is: (255,199,206)

For 'Good' green:

  • The Font Is: (0,97,0)
  • The Background Is: (198,239,206)

For 'Neutral' yellow:

  • The Font Is: (156,101,0)
  • The Background Is: (255,235,156)

Anonymous method in Invoke call

I had problems with the other suggestions because I want to sometimes return values from my methods. If you try to use MethodInvoker with return values it doesn't seem to like it. So the solution I use is like this (very happy to hear a way to make this more succinct - I'm using c#.net 2.0):

    // Create delegates for the different return types needed.
    private delegate void VoidDelegate();
    private delegate Boolean ReturnBooleanDelegate();
    private delegate Hashtable ReturnHashtableDelegate();

    // Now use the delegates and the delegate() keyword to create 
    // an anonymous method as required

    // Here a case where there's no value returned:
    public void SetTitle(string title)
    {
        myWindow.Invoke(new VoidDelegate(delegate()
        {
            myWindow.Text = title;
        }));
    }

    // Here's an example of a value being returned
    public Hashtable CurrentlyLoadedDocs()
    {
        return (Hashtable)myWindow.Invoke(new ReturnHashtableDelegate(delegate()
        {
            return myWindow.CurrentlyLoadedDocs;
        }));
    }

How to set a tkinter window to a constant size

Here is the most simple way.

import tkinter as tk

root = tk.Tk()

root.geometry('200x200')
root.resizable(width=0, height=0)

root.mainloop()

I don't think there is anything to specify. It's pretty straight forward.

How to install xgboost in Anaconda Python (Windows platform)?

Try running this on Anaconda prompt

pip install xgboost

This worked for me on Spyder with Python 3.5

Send private messages to friends

You cannot. Facebook API has read_mailbox but no write_mailbox extended permission. I'm guessing this is done to prevent spammy apps from flooding friend's inboxes.

Passing variable number of arguments around

Though you can solve passing the formatter by storing it in local buffer first, but that needs stack and can sometime be issue to deal with. I tried following and it seems to work fine.

#include <stdarg.h>
#include <stdio.h>

void print(char const* fmt, ...)
{
    va_list arg;
    va_start(arg, fmt);
    vprintf(fmt, arg);
    va_end(arg);
}

void printFormatted(char const* fmt, va_list arg)
{
    vprintf(fmt, arg);
}

void showLog(int mdl, char const* type, ...)
{
    print("\nMDL: %d, TYPE: %s", mdl, type);

    va_list arg;
    va_start(arg, type);
    char const* fmt = va_arg(arg, char const*);
    printFormatted(fmt, arg);
    va_end(arg);
}

int main() 
{
    int x = 3, y = 6;
    showLog(1, "INF, ", "Value = %d, %d Looks Good! %s", x, y, "Infact Awesome!!");
    showLog(1, "ERR");
}

Hope this helps.

How to add element into ArrayList in HashMap

#i'm also maintaining insertion order here
Map<Integer,ArrayList> d=new LinkedHashMap<>();
for( int i=0; i<2; i++)
{
int id=s.nextInt();
ArrayList al=new ArrayList<>();
al.add(s.next());  //name
al.add(s.next());  //category
al.add(s.nextInt()); //fee
d.put(id, al);
 }

Creating a DateTime in a specific Time Zone in c#

The DateTimeOffset structure was created for exactly this type of use.

See: http://msdn.microsoft.com/en-us/library/system.datetimeoffset.aspx

Here's an example of creating a DateTimeOffset object with a specific time zone:

DateTimeOffset do1 = new DateTimeOffset(2008, 8, 22, 1, 0, 0, new TimeSpan(-5, 0, 0));

The SQL OVER() clause - when and why is it useful?

If you only wanted to GROUP BY the SalesOrderID then you wouldn't be able to include the ProductID and OrderQty columns in the SELECT clause.

The PARTITION BY clause let's you break up your aggregate functions. One obvious and useful example would be if you wanted to generate line numbers for order lines on an order:

SELECT
    O.order_id,
    O.order_date,
    ROW_NUMBER() OVER(PARTITION BY O.order_id) AS line_item_no,
    OL.product_id
FROM
    Orders O
INNER JOIN Order_Lines OL ON OL.order_id = O.order_id

(My syntax might be off slightly)

You would then get back something like:

order_id    order_date    line_item_no    product_id
--------    ----------    ------------    ----------
    1       2011-05-02         1              5
    1       2011-05-02         2              4
    1       2011-05-02         3              7
    2       2011-05-12         1              8
    2       2011-05-12         2              1

How to parse data in JSON format?

Can use either json or ast python modules:

Using json :
=============

import json
jsonStr = '{"one" : "1", "two" : "2", "three" : "3"}'
json_data = json.loads(jsonStr)
print(f"json_data: {json_data}")
print(f"json_data['two']: {json_data['two']}")

Output:
json_data: {'one': '1', 'two': '2', 'three': '3'}
json_data['two']: 2




Using ast:
==========

import ast
jsonStr = '{"one" : "1", "two" : "2", "three" : "3"}'
json_dict = ast.literal_eval(jsonStr)
print(f"json_dict: {json_dict}")
print(f"json_dict['two']: {json_dict['two']}")

Output:
json_dict: {'one': '1', 'two': '2', 'three': '3'}
json_dict['two']: 2

Best way to do nested case statement logic in SQL Server

You could try some sort of COALESCE trick, eg:

SELECT COALESCE(
  CASE WHEN condition1 THEN calculation1 ELSE NULL END,
  CASE WHEN condition2 THEN calculation2 ELSE NULL END,
  etc...
)

Saving awk output to variable

I think the $() syntax is easier to read...

variable=$(ps -ef | grep "port 10 -" | grep -v "grep port 10 -"| awk '{printf "%s", $12}')

But the real issue is probably that $12 should not be qouted with ""

Edited since the question was changed, This returns valid data, but it is not clear what the expected output of ps -ef is and what is expected in variable.

How do I use installed packages in PyCharm?

Adding a Path

Go into File ? Settings ? Project Settings ? Project Interpreter.

Then press configure interpreter, and navigate to the "Paths" tab.

pycharm path tab

Press the + button in the Paths area. You can put the path to the module you'd like it to recognize.

But I don't know the path..

Open the python interpreter where you can import the module.

>> import gnuradio
>> gnuradio.__file__
"path/to/gnuradio"

Most commonly you'll have a folder structure like this:

foobarbaz/
  gnuradio/
    __init__.py
    other_file.py

You want to add foobarbaz to the path here.

Binding IIS Express to an IP Address

I think you can.

To do this you need to edit applicationhost.config file manually (edit bindingInformation '<ip-address>:<port>:<host-name>')

To start iisexpress, you need administrator privileges

How to use ArrayList's get() method

You use List#get(int index) to get an object with the index index in the list. You use it like that:

List<ExampleClass> list = new ArrayList<ExampleClass>();
list.add(new ExampleClass());
list.add(new ExampleClass());
list.add(new ExampleClass());
ExampleClass exampleObj = list.get(2); // will get the 3rd element in the list (index 2);

Short circuit Array.forEach like calling break

I use nullhack for that purpose, it tries to access property of null, which is an error:

try {
  [1,2,3,4,5]
  .forEach(
    function ( val, idx, arr ) {
      if ( val == 3 ) null.NULLBREAK;
    }
  );
} catch (e) {
  // e <=> TypeError: null has no properties
}
//

Are there bookmarks in Visual Studio Code?

Under the general heading of 'editors always forget to document getting out…' to toggle go to another line and press the combination ctrl+shift+'N' to erase the current bookmark do the same on marked line…

Change value in a cell based on value in another cell

=IF(A2="Y","Male",IF(A2="N","Female",""))

Dropping connected users in Oracle database

I had the same problem, Oracle config in default affects letter register. In exact my Scheme_Name was written all Capital letters. You can see your Scheme_Name on "Other Users" tab, if you are using Oracle S

How to import an excel file in to a MySQL database

Step 1 Create Your CSV file

Step 2 log in to your mysql server

     mysql -uroot -pyourpassword 

Step 3 load your csv file

     load data local infile '//home/my-sys/my-excel.csv' into table my_tables fields terminated by ',' enclosed by '"' (Country, Amount,Qty);

How do I rename a MySQL schema?

If you're on the Model Overview page you get a tab with the schema. If you rightclick on that tab you get an option to "edit schema". From there you can rename the schema by adding a new name, then click outside the field. This goes for MySQL Workbench 5.2.30 CE

Edit: On the model overview it's under Physical Schemata

Screenshot:

enter image description here

Android Studio cannot resolve R in imported project?

I had the same problem and got it fixed by deleting an extra library.

To do try this solution go to File > Project Structure (on a mac you can use the command "Apple ;")

Then select app on the left tab. Go to the dependencies tab and delete the extra library.

How to handle floats and decimal separators with html5 input type number

I have not found a perfect solution but the best I could do was to use type="tel" and disable html5 validation (formnovalidate):

<input name="txtTest" type="tel" value="1,200.00" formnovalidate="formnovalidate" />

If the user puts in a comma it will output with the comma in every modern browser i tried (latest FF, IE, edge, opera, chrome, safari desktop, android chrome).

The main problem is:

  • Mobile users will see their phone keyboard which may be different than the number keyboard.
  • Even worse the phone keyboard may not even have a key for a comma.

For my use case I only had to:

  • Display the initial value with a comma (firefox strips it out for type=number)
  • Not fail html5 validation (if there is a comma)
  • Have the field read exactly as input (with a possible comma)

If you have a similar requirement this should work for you.

Note: I did not like the support of the pattern attribute. The formnovalidate seems to work much better.

Swift addsubview and remove it

You have to use the viewWithTag function to find the view with the given tag.

override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
    let touch = touches.anyObject() as UITouch
    let point = touch.locationInView(self.view)

    if let viewWithTag = self.view.viewWithTag(100) {
        print("Tag 100")
        viewWithTag.removeFromSuperview()
    } else {
        print("tag not found")
    }
}

How to check if an email address is real or valid using PHP

I have been searching for this same answer all morning and have pretty much found out that it's probably impossible to verify if every email address you ever need to check actually exists at the time you need to verify it. So as a work around, I kind of created a simple PHP script to verify that the email address is formatted correct and it also verifies that the domain name used is correct as well.

GitHub here https://github.com/DukeOfMarshall/PHP---JSON-Email-Verification/tree/master

<?php

# What to do if the class is being called directly and not being included in a script     via PHP
# This allows the class/script to be called via other methods like JavaScript

if(basename(__FILE__) == basename($_SERVER["SCRIPT_FILENAME"])){
$return_array = array();

if($_GET['address_to_verify'] == '' || !isset($_GET['address_to_verify'])){
    $return_array['error']              = 1;
    $return_array['message']            = 'No email address was submitted for verification';
    $return_array['domain_verified']    = 0;
    $return_array['format_verified']    = 0;
}else{
    $verify = new EmailVerify();

    if($verify->verify_formatting($_GET['address_to_verify'])){
        $return_array['format_verified']    = 1;

        if($verify->verify_domain($_GET['address_to_verify'])){
            $return_array['error']              = 0;
            $return_array['domain_verified']    = 1;
            $return_array['message']            = 'Formatting and domain have been verified';
        }else{
            $return_array['error']              = 1;
            $return_array['domain_verified']    = 0;
            $return_array['message']            = 'Formatting was verified, but verification of the domain has failed';
        }
    }else{
        $return_array['error']              = 1;
        $return_array['domain_verified']    = 0;
        $return_array['format_verified']    = 0;
        $return_array['message']            = 'Email was not formatted correctly';
    }
}

echo json_encode($return_array);

exit();
}

class EmailVerify {
public function __construct(){

}

public function verify_domain($address_to_verify){
    // an optional sender  
    $record = 'MX';
    list($user, $domain) = explode('@', $address_to_verify);
    return checkdnsrr($domain, $record);
}

public function verify_formatting($address_to_verify){
    if(strstr($address_to_verify, "@") == FALSE){
        return false;
    }else{
        list($user, $domain) = explode('@', $address_to_verify);

        if(strstr($domain, '.') == FALSE){
            return false;
        }else{
            return true;
        }
    }
    }
}
?>

Curl command without using cache

I know this is an older question, but I wanted to post an answer for users with the same question:

curl -H 'Cache-Control: no-cache' http://www.example.com

This curl command servers in its header request to return non-cached data from the web server.

Android Imagebutton change Image OnClick

<ImageButton android:src="@drawable/image_btn_src" ... />

image_btn_src.xml

<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" android:drawable="@drawable/icon_pressed"/>
<item android:state_pressed="false" android:drawable="@drawable/icon_unpressed"/>
</selector>

Query for array elements inside JSON type

jsonb in Postgres 9.4+

You can use the same query as below, just with jsonb_array_elements().

But rather use the jsonb "contains" operator @> in combination with a matching GIN index on the expression data->'objects':

CREATE INDEX reports_data_gin_idx ON reports
USING gin ((data->'objects') jsonb_path_ops);

SELECT * FROM reports WHERE data->'objects' @> '[{"src":"foo.png"}]';

Since the key objects holds a JSON array, we need to match the structure in the search term and wrap the array element into square brackets, too. Drop the array brackets when searching a plain record.

More explanation and options:

json in Postgres 9.3+

Unnest the JSON array with the function json_array_elements() in a lateral join in the FROM clause and test for its elements:

SELECT data::text, obj
FROM   reports r, json_array_elements(r.data#>'{objects}') obj
WHERE  obj->>'src' = 'foo.png';

db<>fiddle here
Old sqlfiddle

The CTE (WITH query) just substitutes for a table reports.
Or, equivalent for just a single level of nesting:

SELECT *
FROM   reports r, json_array_elements(r.data->'objects') obj
WHERE  obj->>'src' = 'foo.png';

->>, -> and #> operators are explained in the manual.

Both queries use an implicit JOIN LATERAL.

Closely related:

Column calculated from another column?

@krtek's answer is in the right direction, but has a couple of issues.

The bad news is that using UPDATE in a trigger on the same table won't work. The good news is that it's not necessary; there is a NEW object that you can operate on before the table is even touched.

The trigger becomes:

CREATE TRIGGER halfcolumn_update BEFORE UPDATE ON my_table
  FOR EACH ROW BEGIN
    SET NEW.calculated = NEW.value/2;
  END;

Note also that the BEGIN...END; syntax has to be parsed with a different delimiter in effect. The whole shebang becomes:

DELIMITER |

CREATE TRIGGER halfcolumn_insert BEFORE INSERT ON my_table
  FOR EACH ROW BEGIN
    SET NEW.calculated = NEW.value/2;
  END;
|

CREATE TRIGGER halfcolumn_update BEFORE UPDATE ON my_table
  FOR EACH ROW BEGIN
    SET NEW.calculated = NEW.value/2;
  END;
|

DELIMITER ;

Java FileReader encoding issue

For Java 7+ doc you can use this:

BufferedReader reader = Files.newBufferedReader(path, StandardCharsets.UTF_8);

Here are all Charsets doc

For example if your file is in CP1252, use this method

Charset.forName("windows-1252");

Here is other canonical names for Java encodings both for IO and NIO doc

If you do not know with exactly encoding you have got in a file, you may use some third-party libs like this tool from Google this which works fairly neat.

how to download file in react js

Download file


For downloading you can use multiple ways as been explained above, moreover I will also provide my strategy for this scenario.

  1. npm install --save react-download-link
  2. import DownloadLink from "react-download-link";
  3. React download link for client side cache data
    <DownloadLink 
        label="Download" 
        filename="fileName.txt"
        exportFile={() => "Client side cache data here…"}
    />
    
  4. Download link for client side cache data with Promises
    <DownloadLink
        label="Download with Promise"
        filename="fileName.txt"
        exportFile={() => Promise.resolve("cached data here …")}
    />
    
  5. Download link for data from URL with Promises Function to Fetch data from URL
     getDataFromURL = (url) => new Promise((resolve, reject) => {
        setTimeout(() => {
            fetch(url)
                .then(response => response.text())
                .then(data => {
                    resolve(data)
                });
        });
    }, 2000);
    
  6. DownloadLink component calling Fetch function
    <DownloadLink
          label=”Download”
          filename=”filename.txt”
          exportFile={() => Promise.resolve(this. getDataFromURL (url))}
    />
    

Happy coding! ;)

Typescript Date Type?

The answer is super simple, the type is Date:

const d: Date = new Date(); // but the type can also be inferred from "new Date()" already

It is the same as with every other object instance :)

Selected tab's color in Bottom Navigation View

In order to set textColor, BottomNavigationView has two style properties you can set directly from the xml:

  • itemTextAppearanceActive
  • itemTextAppearanceInactive

In your layout.xml file:

<com.google.android.material.bottomnavigation.BottomNavigationView
            android:id="@+id/bnvMainNavigation"
            style="@style/NavigationView"/>
  

In your styles.xml file:

    <style name="NavigationView" parent="Widget.MaterialComponents.BottomNavigationView">
      <item name="itemTextAppearanceActive">@style/ActiveText</item>
      <item name="itemTextAppearanceInactive">@style/InactiveText</item>
    </style>
    <style name="ActiveText">
      <item name="android:textColor">@color/colorPrimary</item>
    </style>
    <style name="InactiveText">
      <item name="android:textColor">@color/colorBaseBlack</item>
    </style>

How to install 2 Anacondas (Python 2 and 3) on Mac OS

There is no need to install Anaconda again. Conda, the package manager for Anaconda, fully supports separated environments. The easiest way to create an environment for Python 2.7 is to do

conda create -n python2 python=2.7 anaconda

This will create an environment named python2 that contains the Python 2.7 version of Anaconda. You can activate this environment with

source activate python2

This will put that environment (typically ~/anaconda/envs/python2) in front in your PATH, so that when you type python at the terminal it will load the Python from that environment.

If you don't want all of Anaconda, you can replace anaconda in the command above with whatever packages you want. You can use conda to install packages in that environment later, either by using the -n python2 flag to conda, or by activating the environment.

(grep) Regex to match non-ASCII characters?

You don't really need a regex.

printf "%s\n" *[!\ -~]*

This will show file names with control characters in their names, too, but I consider that a feature.

If you don't have any matching files, the glob will expand to just itself, unless you have nullglob set. (The expression does not match itself, so technically, this output is unambiguous.)

How to convert string to binary?

Something like this?

>>> st = "hello world"
>>> ' '.join(format(ord(x), 'b') for x in st)
'1101000 1100101 1101100 1101100 1101111 100000 1110111 1101111 1110010 1101100 1100100'

#using `bytearray`
>>> ' '.join(format(x, 'b') for x in bytearray(st, 'utf-8'))
'1101000 1100101 1101100 1101100 1101111 100000 1110111 1101111 1110010 1101100 1100100'

How to get 0-padded binary representation of an integer in java?

Starting with Java 11, you can use the repeat(...) method:

"0".repeat(Integer.numberOfLeadingZeros(i) - 16) + Integer.toBinaryString(i)

Or, if you need 32-bit representation of any integer:

"0".repeat(Integer.numberOfLeadingZeros(i != 0 ? i : 1)) + Integer.toBinaryString(i)

How to make an ImageView with rounded corners?

Apply a shape to your imageView as below:

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle" >
    <solid android:color="#faf5e6" />
    <stroke
        android:width="1dp"
        android:color="#808080" />
    <corners android:radius="15dp" />
    <padding
        android:bottom="5dp"
        android:left="5dp"
        android:right="5dp"
        android:top="5dp" />
</shape>

it may be helpful to you friend.

How to deep watch an array in angularjs?

If you're going to watch only one array, you can simply use this bit of code:

$scope.$watch('columns', function() {
  // some value in the array has changed 
}, true); // watching properties

example

But this will not work with multiple arrays:

$scope.$watch('columns + ANOTHER_ARRAY', function() {
  // will never be called when things change in columns or ANOTHER_ARRAY
}, true);

example

To handle this situation, I usually convert the multiple arrays I want to watch into JSON:

$scope.$watch(function() { 
  return angular.toJson([$scope.columns, $scope.ANOTHER_ARRAY, ... ]); 
},
function() {
  // some value in some array has changed
}

example

As @jssebastian pointed out in the comments, JSON.stringify may be preferable to angular.toJson as it can handle members that start with '$' and possible other cases as well.

invalid target release: 1.7

When maven is working outside of Eclipse, but giving this error after a JDK change, Go to your Maven Run Configuration, and at the bottom of the Main page, there's a 'Maven Runtime' option. Mine was using the Embedded Maven, so after switching it to use my external maven, it worked.

How do you underline a text in Android XML?

If you are using a string resource xml file (supports HTML tags), it can be done using<b> </b>, <i> </i> and <u> </u>.

<resources>
    <string name="your_string_here">
        This is an <u>underline</u>.
    </string>
</resources>

If you want to underline something from code use:

TextView tv = (TextView) view.findViewById(R.id.tv);
SpannableString content = new SpannableString("Content");
content.setSpan(new UnderlineSpan(), 0, content.length(), 0);
tv.setText(content);

Hope this helps

DataGridView - Focus a specific cell

Just Simple Paste And Pass Gridcolor() any where You want.

Private Sub Gridcolor()
    With Me.GridListAll
        .SelectionMode = DataGridViewSelectionMode.FullRowSelect
        .MultiSelect = False
        '.DefaultCellStyle.SelectionBackColor = Color.MediumOrchid
    End With
End Sub

How can I set a proxy server for gem?

When setting http_proxy and https_proxy, you are also probably going to need no_proxy for URLs on the same side of the proxy. https://msdn.microsoft.com/en-us/library/hh272656(v=vs.120).aspx

Changing the current working directory in Java?

The other possible answer to this question may depend on the reason you are opening the file. Is this a property file or a file that has some configuration related to your application?

If this is the case you may consider trying to load the file through the classpath loader, this way you can load any file Java has access to.

Meaning of .Cells(.Rows.Count,"A").End(xlUp).row

It is used to find the how many rows contain data in a worksheet that contains data in the column "A". The full usage is

 lastRowIndex = ws.Cells(ws.Rows.Count, "A").End(xlUp).row

Where ws is a Worksheet object. In the questions example it was implied that the statement was inside a With block

With ws
    lastRowIndex = .Cells(.Rows.Count, "A").End(xlUp).row
End With
  1. ws.Rows.Count returns the total count of rows in the worksheet (1048576 in Excel 2010).
  2. .Cells(.Rows.Count, "A") returns the bottom most cell in column "A" in the worksheet

Then there is the End method. The documentation is ambiguous as to what it does.

Returns a Range object that represents the cell at the end of the region that contains the source range

Particularly it doesn't define what a "region" is. My understanding is a region is a contiguous range of non-empty cells. So the expected usage is to start from a cell in a region and find the last cell in that region in that direction from the original cell. However there are multiple exceptions for when you don't use it like that:

  • If the range is multiple cells, it will use the region of rng.cells(1,1).
  • If the range isn't in a region, or the range is already at the end of the region, then it will travel along the direction until it enters a region and return the first encountered cell in that region.
  • If it encounters the edge of the worksheet it will return the cell on the edge of that worksheet.

So Range.End is not a trivial function.

  1. .row returns the row index of that cell.

How to remove the focus from a TextBox in WinForms?

Try this one:

First set up tab order.

Then in form load event we can send a tab key press programmatically to application. So that application will give focus to 1st contol in the tab order.

in form load even write this line.

SendKeys.Send("{TAB}");

This did work for me.

How to redirect to a route in laravel 5 by using href tag if I'm not using blade or any template?

In you app config file change the url to localhost/example/public

Then when you want to link to something

<a href="{{ url('page') }}">Some Text</a>

without blade

<a href="<?php echo url('page') ?>">Some Text</a>

Where to put a textfile I want to use in eclipse?

You should probably take a look at the various flavours of getResource in the ClassLoader class: https://docs.oracle.com/javase/1.5.0/docs/api/java/lang/ClassLoader.html.

Pad a string with leading zeros so it's 3 characters long in SQL Server 2008

Wrote this because I had requirements for up to a specific length (9). Pads the left with the @pattern ONLY when the input needs padding. Should always return length defined in @pattern.

declare @charInput as char(50) = 'input'

--always handle NULL :)
set @charInput = isnull(@charInput,'')

declare @actualLength as int = len(@charInput)

declare @pattern as char(50) = '123456789'
declare @prefLength as int = len(@pattern)

if @prefLength > @actualLength
    select Left(Left(@pattern, @prefLength-@actualLength) + @charInput, @prefLength)
else
    select @charInput

Returns 1234input

selected value get from db into dropdown select box option using php mysql error

THE EASIEST SOLUTION

It will add an extra in your options but your problem will be solved.

<?php 
    if ($editing == Yes) {
        echo "<option value=\".$MyValue.\" SELECTED>".$MyValue."</option>";
    }
?>

Insert current date/time using now() in a field using MySQL/PHP

The only reason I can think of is you are adding it as string 'now()', not function call now().
Or whatever else typo.

SELECT NOW();

to see if it returns correct value?

Java System.out.print formatting

Are you sure that you want "055" as opposed to "55"? Some programs interpret a leading zero as meaning octal, so that it would read 055 as (decimal) 45 instead of (decimal) 55.

That should just mean dropping the '0' (zero-fill) flag.

e.g., change System.out.printf("%03d ", x); to the simpler System.out.printf("%3d ", x);

How to set a border for an HTML div tag

In bootstrap 4, you can use border utilities like so.

_x000D_
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" rel="stylesheet" />_x000D_
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"></script>_x000D_
_x000D_
<style>_x000D_
  .border-5 {_x000D_
    border-width: 5px !important;_x000D_
  }_x000D_
</style>_x000D_
_x000D_
<textarea class="border border-dark border-5">some content</textarea>
_x000D_
_x000D_
_x000D_

In Bash, how to add "Are you sure [Y/n]" to any command or alias?

Confirmations are easily bypassed with carriage returns, and I find it useful to continually prompt for valid input.

Here's a function to make this easy. "invalid input" appears in red if Y|N is not received, and the user is prompted again.

prompt_confirm() {
  while true; do
    read -r -n 1 -p "${1:-Continue?} [y/n]: " REPLY
    case $REPLY in
      [yY]) echo ; return 0 ;;
      [nN]) echo ; return 1 ;;
      *) printf " \033[31m %s \n\033[0m" "invalid input"
    esac 
  done  
}

# example usage
prompt_confirm "Overwrite File?" || exit 0

You can change the default prompt by passing an argument

Sites not accepting wget user agent header

You need to set both the user-agent and the referer:

 wget  --header="Accept: text/html" --user-agent="Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:21.0) Gecko/20100101 Firefox/21.0" --referrer  connect.wso2.com http://dist.wso2.org/products/carbon/4.2.0/wso2carbon-4.2.0.zip

WAMP error: Forbidden You don't have permission to access /phpmyadmin/ on this server

If WampServer works in the computer it is installed but not on another device in your network (e.g.: from your phone) with the 'You don't have permission to access on this server.' try the following.

1. Edit the httpd-vhosts.conf (C:\wamp64\bin\apache\apache2.4.33\conf\extra\httpd-vhosts.conf), so it looks like this:

<Directory "${INSTALL_DIR}/www/">
    Options +Indexes +Includes +FollowSymLinks +MultiViews
    AllowOverride All
    Require all granted
</Directory>

2. Edit the phpmyadmin.conf (C:\wamp64\alias\phpmyadmin.conf), so it looks like this:

<Directory "d:/wamp64/apps/phpmyadmin4.7.9/">
    Options +Indexes +FollowSymLinks +MultiViews
    AllowOverride all
        Order Deny,Allow
        Allow from all
        Require all granted

3. Restart WampServer services

Command to change the default home directory of a user

Ibrahim's comment on the other answer is the correct way to alter an existing user's home directory.

Change the user's home directory:

usermod -d /newhome/username username

usermod is the command to edit an existing user.
-d (abbreviation for --home) will change the user's home directory.

Change the user's home directory + Move the contents of the user's current directory:

usermod -m -d /newhome/username username

-m (abbreviation for --move-home) will move the content from the user's current directory to the new directory.

Increasing the maximum number of TCP/IP connections in Linux

Maximum number of connections are impacted by certain limits on both client & server sides, albeit a little differently.

On the client side: Increase the ephermal port range, and decrease the tcp_fin_timeout

To find out the default values:

sysctl net.ipv4.ip_local_port_range
sysctl net.ipv4.tcp_fin_timeout

The ephermal port range defines the maximum number of outbound sockets a host can create from a particular I.P. address. The fin_timeout defines the minimum time these sockets will stay in TIME_WAIT state (unusable after being used once). Usual system defaults are:

  • net.ipv4.ip_local_port_range = 32768 61000
  • net.ipv4.tcp_fin_timeout = 60

This basically means your system cannot consistently guarantee more than (61000 - 32768) / 60 = 470 sockets per second. If you are not happy with that, you could begin with increasing the port_range. Setting the range to 15000 61000 is pretty common these days. You could further increase the availability by decreasing the fin_timeout. Suppose you do both, you should see over 1500 outbound connections per second, more readily.

To change the values:

sysctl net.ipv4.ip_local_port_range="15000 61000"
sysctl net.ipv4.tcp_fin_timeout=30

The above should not be interpreted as the factors impacting system capability for making outbound connections per second. But rather these factors affect system's ability to handle concurrent connections in a sustainable manner for large periods of "activity."

Default Sysctl values on a typical Linux box for tcp_tw_recycle & tcp_tw_reuse would be

net.ipv4.tcp_tw_recycle=0
net.ipv4.tcp_tw_reuse=0

These do not allow a connection from a "used" socket (in wait state) and force the sockets to last the complete time_wait cycle. I recommend setting:

sysctl net.ipv4.tcp_tw_recycle=1
sysctl net.ipv4.tcp_tw_reuse=1 

This allows fast cycling of sockets in time_wait state and re-using them. But before you do this change make sure that this does not conflict with the protocols that you would use for the application that needs these sockets. Make sure to read post "Coping with the TCP TIME-WAIT" from Vincent Bernat to understand the implications. The net.ipv4.tcp_tw_recycle option is quite problematic for public-facing servers as it won’t handle connections from two different computers behind the same NAT device, which is a problem hard to detect and waiting to bite you. Note that net.ipv4.tcp_tw_recycle has been removed from Linux 4.12.

On the Server Side: The net.core.somaxconn value has an important role. It limits the maximum number of requests queued to a listen socket. If you are sure of your server application's capability, bump it up from default 128 to something like 128 to 1024. Now you can take advantage of this increase by modifying the listen backlog variable in your application's listen call, to an equal or higher integer.

sysctl net.core.somaxconn=1024

txqueuelen parameter of your ethernet cards also have a role to play. Default values are 1000, so bump them up to 5000 or even more if your system can handle it.

ifconfig eth0 txqueuelen 5000
echo "/sbin/ifconfig eth0 txqueuelen 5000" >> /etc/rc.local

Similarly bump up the values for net.core.netdev_max_backlog and net.ipv4.tcp_max_syn_backlog. Their default values are 1000 and 1024 respectively.

sysctl net.core.netdev_max_backlog=2000
sysctl net.ipv4.tcp_max_syn_backlog=2048

Now remember to start both your client and server side applications by increasing the FD ulimts, in the shell.

Besides the above one more popular technique used by programmers is to reduce the number of tcp write calls. My own preference is to use a buffer wherein I push the data I wish to send to the client, and then at appropriate points I write out the buffered data into the actual socket. This technique allows me to use large data packets, reduce fragmentation, reduces my CPU utilization both in the user land and at kernel-level.

How to install php-curl in Ubuntu 16.04

For Ubuntu 18.04 or PHP 7.2 users you can do:

apt-get install php7.2-curl

You can check your PHP version by running php -v to verify your PHP version and get the right curl version.

postgresql: INSERT INTO ... (SELECT * ...)

insert into TABLENAMEA (A,B,C,D) 
select A::integer,B,C,D from TABLENAMEB

Entity Framework - "An error occurred while updating the entries. See the inner exception for details"

I faced the same error :

"An error occurred while updating the entries. See the inner exception for details”

Simply Delete and Recreate the *.edmx file. Its worked for me. the error will gone

How do I use Notepad++ (or other) with msysgit?

I use the approach with PATH variable. Path to Notepad++ is added to system's PATH variable and then core.editor is set like following:

git config --global core.editor notepad++

Also, you may add some additional parameters for Notepad++:

git config --global core.editor "notepad++.exe -multiInst"

(as I detailed in "Git core.editor for Windows")

And here you can find some options you may use when stating Notepad++ Command Line Options.

What is the OR operator in an IF statement

Or is ||

And is &&

Update for changed question:

You need to specify what you are comparing against in each logical section of the if statement.

if (title == "User greeting" || title == "User name") 
{
    // do stuff
}

Digital Certificate: How to import .cer file in to .truststore file using?

# Copy the certificate into the directory Java_home\Jre\Lib\Security
# Change your directory to Java_home\Jre\Lib\Security>
# Import the certificate to a trust store.

keytool -import -alias ca -file somecert.cer -keystore cacerts -storepass changeit [Return]

Trust this certificate: [Yes]

changeit is the default truststore password

How can I set the maximum length of 6 and minimum length of 6 in a textbox?

You can't set a minimum length on a text field. Otherwise, users wouldn't be able to type in the first five characters.

Your best bet is to validate the input when the form is submitted to ensure that the length is six.

maxlength is not a validation attribute. It is designed to prevent the user from physically typing in more than six characters. The corresponding minlengh is not in scope of the HTML specification, because its implementation would render the textbox unusable.

Returning a pointer to a vector element in c++

Returning &iterator will return the address of the iterator. If you want to return a way of referring to the element return the iterator itself.

Beware that you do not need the vector to be a global in order to return the iterator/pointer, but that operations in the vector can invalidate the iterator. Adding elements to the vector, for example, can move the vector elements to a different position if the new size() is greater than the reserved memory. Deletion of an element before the given item from the vector will make the iterator refer to a different element.

In both cases, depending on the STL implementation it can be hard to debug with just random errors happening each so often.

EDIT after comment: 'yes, I didn't want to return the iterator a) because its const, and b) surely it is only a local, temporary iterator? – Krakkos'

Iterators are not more or less local or temporary than any other variable and they are copyable. You can return it and the compiler will make the copy for you as it will with the pointer.

Now with the const-ness. If the caller wants to perform modifications through the returned element (whether pointer or iterator) then you should use a non-const iterator. (Just remove the 'const_' from the definition of the iterator).

Disable spell-checking on HTML textfields

While specifying spellcheck="false" in the < tag > will certainly disable that feature, it's handy to be able to toggle that functionality on and off as needed after the page has loaded. So here's a non-jQuery way to set the spellcheck attribute programmatically:

:

<textarea id="my-ta" spellcheck="whatever">abcd dcba</textarea>

:

function setSpellCheck( mode ) {
    var myTextArea = document.getElementById( "my-ta" )
        , myTextAreaValue = myTextArea.value
    ;
    myTextArea.value = '';
    myTextArea.setAttribute( "spellcheck", String( mode ) );
    myTextArea.value = myTextAreaValue;
    myTextArea.focus();
}

:

setSpellCheck( true );
setSpellCheck( 'false' );

The function argument may be either boolean or string.

No need to loop through the textarea contents, we just cut 'n paste what's there, and then set focus.

Tested in blink engines (Chrome(ium), Edge, etc.)

How do I get to IIS Manager?

You need to make sure the IIS Management Console is installed.

Converting an int or String to a char array on Arduino

You can convert it to char* if you don't need a modifiable string by using:

(char*) yourString.c_str();

This would be very useful when you want to publish a String variable via MQTT in arduino.

How to upload folders on GitHub

I've just gone through that process again. Always end up cloning the repo locally, upload the folder I want to have in that repo to that cloned location, commit the changes and then push it.

Note that if you're dealing with large files, you'll need to consider using something like Git LFS.

How to get child element by index in Jquery?

$('.second').find('div:first')

How to access site through IP address when website is on a shared host?

You can access you website using your IP address and your cPanel username with ~ symbols. For Example: http://serverip/~cpusername like as https://xxx.xxx.xx.xx/~mohidul

How do I get the current date and current time only respectively in Django?

 import datetime

Current Date and time

     print(datetime.datetime.now())
     #2019-09-08 09:12:12.473393

Current date only

     print(datetime.date.today())
     #2019-09-08

Current year only

     print(datetime.date.today().year)
     #2019

Current month only

     print(datetime.date.today().month)
     #9

Current day only

     print(datetime.date.today().day)
     #8

How to send SMS in Java

The best SMS API I've seen in Java is JSMPP. It is powerful, easy to use, and I used it myself for an enterprise-level application (sending over 20K SMS messages daily).

This API created to reduce the verbosity of the existing SMPP API. It's very simple and easy to use because it hides the complexity of the low level protocol communication such as automatically enquire link request-response.

I've tried some other APIs such as Ozeki, but most of them either is commercial or has limitation in its throughput (i.e can't send more than 3 SMS messages in a second, for example).

How to install a Notepad++ plugin offline?

as an aside, i Couldnt import the .dll if it was already in the plugins folder. I put it in a temp folder on the C drive, and it worked perfectly.

.toLowerCase not working, replacement function?

.toLowerCase function only exists on strings. You can call toString() on anything in javascript to get a string representation. Putting this all together:

var ans = 334;
var temp = ans.toString().toLowerCase();
alert(temp);

Is it possible to have empty RequestParam values use the defaultValue?

You could change the @RequestParam type to an Integer and make it not required. This would allow your request to succeed, but it would then be null. You could explicitly set it to your default value in the controller method:

@RequestMapping(value = "/test", method = RequestMethod.POST)
@ResponseBody
public void test(@RequestParam(value = "i", required=false) Integer i) {
    if(i == null) {
        i = 10;
    }
    // ...
}

I have removed the defaultValue from the example above, but you may want to include it if you expect to receive requests where it isn't set at all:

http://example.com/test

PHP - Check if two arrays are equal

Short solution that works even with arrays which keys are given in different order:

public static function arrays_are_equal($array1, $array2)
{
    array_multisort($array1);
    array_multisort($array2);
    return ( serialize($array1) === serialize($array2) );
}

Binary search (bisection) in Python

I needed binary search in python and generic for Django models. In Django models, one model can have foreign key to another model and I wanted to perform some search on the retrieved models objects. I wrote following function you can use this.

def binary_search(values, key, lo=0, hi=None, length=None, cmp=None):
    """
    This is a binary search function which search for given key in values.
    This is very generic since values and key can be of different type.
    If they are of different type then caller must specify `cmp` function to
    perform a comparison between key and values' item.
    :param values:  List of items in which key has to be search
    :param key: search key
    :param lo: start index to begin search
    :param hi: end index where search will be performed
    :param length: length of values
    :param cmp: a comparator function which can be used to compare key and values
    :return: -1 if key is not found else index
    """
    assert type(values[0]) == type(key) or cmp, "can't be compared"
    assert not (hi and length), "`hi`, `length` both can't be specified at the same time"

    lo = lo
    if not lo:
        lo = 0
    if hi:
        hi = hi
    elif length:
        hi = length - 1
    else:
        hi = len(values) - 1

    while lo <= hi:
        mid = lo + (hi - lo) // 2
        if not cmp:
            if values[mid] == key:
                return mid
            if values[mid] < key:
                lo = mid + 1
            else:
                hi = mid - 1
        else:
            val = cmp(values[mid], key)
            # 0 -> a == b
            # > 0 -> a > b
            # < 0 -> a < b
            if val == 0:
                return mid
            if val < 0:
                lo = mid + 1
            else:
                hi = mid - 1
    return -1

How to use particular CSS styles based on screen size / device

I created a little javascript tool to style elements on screen size without using media queries or recompiling bootstrap css:

https://github.com/Heras/Responsive-Breakpoints

Just add class responsive-breakpoints to any element, and it will automagically add xs sm md lg xl classes to those elements.

Demo: https://codepen.io/HerasHackwork/pen/rGGNEK

How to properly create composite primary keys - MYSQL

Suppose you have already created a table now you can use this query to make composite primary key

alter table employee add primary key(emp_id,emp_name);

How can I reorder a list?

newList = [oldList[3]]
newList.extend(oldList[:3])
newList.extend(oldList[4:])

Size-limited queue that holds last N elements in Java

Apache commons collections 4 has a CircularFifoQueue<> which is what you are looking for. Quoting the javadoc:

CircularFifoQueue is a first-in first-out queue with a fixed size that replaces its oldest element if full.

    import java.util.Queue;
    import org.apache.commons.collections4.queue.CircularFifoQueue;

    Queue<Integer> fifo = new CircularFifoQueue<Integer>(2);
    fifo.add(1);
    fifo.add(2);
    fifo.add(3);
    System.out.println(fifo);

    // Observe the result: 
    // [2, 3]

If you are using an older version of the Apache commons collections (3.x), you can use the CircularFifoBuffer which is basically the same thing without generics.

Update: updated answer following release of commons collections version 4 that supports generics.

Retrieve a Fragment from a ViewPager

In Fragment

public int getArgument(){
   return mPage;
{
public void update(){

}

In FragmentActivity

List<Fragment> fragments = getSupportFragmentManager().getFragments();
for(Fragment f:fragments){
    if((f instanceof PageFragment)&&(!f.isDetached())){
          PageFragment pf = (PageFragment)f;   
          if(pf.getArgument()==pager.getCurrentItem())pf.update();
    }
}

Open PDF in new browser full window

var pdf = MyPdf.pdf;
window.open(pdf);

This will open the pdf document in a full window from JavaScript

A function to open windows would look like this:

function openPDF(pdf){
  window.open(pdf);
  return false;
}

sys.argv[1], IndexError: list index out of range

sys.argv represents the command line options you execute a script with.

sys.argv[0] is the name of the script you are running. All additional options are contained in sys.argv[1:].

You are attempting to open a file that uses sys.argv[1] (the first argument) as what looks to be the directory.

Try running something like this:

python ConcatenateFiles.py /tmp

How to unbind a listener that is calling event.preventDefault() (using jQuery)?

In my case:

$('#some_link').click(function(event){
    event.preventDefault();
});

$('#some_link').unbind('click'); worked as the only method to restore the default action.

As seen over here: https://stackoverflow.com/a/1673570/211514

remove empty lines from text file with PowerShell

This will remove empty lines or lines with only whitespace characters (tabs/spaces).

[IO.File]::ReadAllText("FileWithEmptyLines.txt") -replace '\s+\r\n+', "`r`n" | Out-File "c:\FileWithNoEmptyLines.txt"

How to make correct date format when writing data to Excel

Try this solution, in my softwarew work very well:

if (obj != null)
{
    if (obj is DateTime)
    {
        if (DateTime.MinValue == ((DateTime)obj))
        {

            xlWorkSheet.Cells[x,y] = String.Empty;

        }
        else
        {

            dynamic opp = ((DateTime)obj);
            xlWorkSheet.Cells[x,y] = (DateTime)opp;

        }
    }
}

port 8080 is already in use and no process using 8080 has been listed

In windows " wmic process where processid="pid of the process running" get commandline " worked for me. The culprit was wrapper.exe process of webhuddle jboss soft.

Correct location of openssl.cnf file

RHEL: /etc/pki/tls/openssl.cnf

Session variables in ASP.NET MVC

My way of accessing sessions is to write a helper class which encapsulates the various field names and their types. I hope this example helps:

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.SessionState;

namespace dmkp
{
    /// <summary>
    /// Encapsulates the session state
    /// </summary>
    public sealed class LoginInfo
    {
        private HttpSessionState _session;
        public LoginInfo(HttpSessionState session)
        {
            this._session = session;
        }

        public string Username
        {
            get { return (this._session["Username"] ?? string.Empty).ToString(); }
            set { this._session["Username"] = value; }
        }

        public string FullName
        {
            get { return (this._session["FullName"] ?? string.Empty).ToString(); }
            set { this._session["FullName"] = value; }
        }
        public int ID
        {
            get { return Convert.ToInt32((this._session["UID"] ?? -1)); }
            set { this._session["UID"] = value; }
        }

        public UserAccess AccessLevel
        {
            get { return (UserAccess)(this._session["AccessLevel"]); }
            set { this._session["AccessLevel"] = value; }
        }

    }
}

Construct pandas DataFrame from list of tuples of (row,col,values)

I submit that it is better to leave your data stacked as it is:

df = pandas.DataFrame(data, columns=['R_Number', 'C_Number', 'Avg', 'Std'])

# Possibly also this if these can always be the indexes:
# df = df.set_index(['R_Number', 'C_Number'])

Then it's a bit more intuitive to say

df.set_index(['R_Number', 'C_Number']).Avg.unstack(level=1)

This way it is implicit that you're seeking to reshape the averages, or the standard deviations. Whereas, just using pivot, it's purely based on column convention as to what semantic entity it is that you are reshaping.

Flask Value error view function did not return a response

You are not returning a response object from your view my_form_post. The function ends with implicit return None, which Flask does not like.

Make the function my_form_post return an explicit response, for example

return 'OK'

at the end of the function.

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

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

Python 3

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


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

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

            raise exception

    return forced_error_output

Python 2

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


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

            raise exception

    return forced_error_output

Then in your worker just use the decorator

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

What are .tpl files? PHP, web design

.tpl is the extension for Smarty files. It means "template".

Tip: if you are using NetBeans and you want a correct syntax highlighting for those files:

  • Go to menu Options ? Tools
  • Under Miscellaneous, select the Files tab
  • Click new file extension, enter tpl.
  • In Associated File Type (MIME), select HTML Files (text/html)
  • Click OK

INSERT INTO...SELECT for all MySQL columns

The correct syntax is described in the manual. Try this:

INSERT INTO this_table_archive (col1, col2, ..., coln)
SELECT col1, col2, ..., coln
FROM this_table
WHERE entry_date < '2011-01-01 00:00:00';

If the id columns is an auto-increment column and you already have some data in both tables then in some cases you may want to omit the id from the column list and generate new ids instead to avoid insert an id that already exists in the original table. If your target table is empty then this won't be an issue.

Convert AM/PM time to 24 hours format?

You can use the ParseExact() method to obtain a DateTime object. You can then use the ToString() method of that DateTime object to convert the string to what ever you need as shown here.

How to access global js variable in AngularJS directive

I created a working CodePen example demonstrating how to do this the correct way in AngularJS. The Angular $window service should be used to access any global objects since directly accessing window makes testing more difficult.

HTML:

<section ng-app="myapp" ng-controller="MainCtrl">
  Value of global variable read by AngularJS: {{variable1}}
</section>

JavaScript:

// global variable outside angular
var variable1 = true;

var app = angular.module('myapp', []);

app.controller('MainCtrl', ['$scope', '$window', function($scope, $window) {
  $scope.variable1 = $window.variable1;
}]);

Regex match one of two words

This will do:

/^(apple|banana)$/

to exclude from captured strings (e.g. $1,$2):

(?:apple|banana)

Pandas DataFrame: replace all values in a column, based on condition

Another option is to use a list comprehension:

df['First Season'] = [1 if year > 1990 else year for year in df['First Season']]

How to export iTerm2 Profiles

If you have a look at Preferences -> General you will notice at the bottom of the panel, there is a setting Load preferences from a custom folder or URL:. There is a button next to it Save settings to Folder.

So all you need to do is save your settings first and load it after you reinstalled your OS.

If the Save settings to Folder is disabled, select a folder (e.g. empty) in the Load preferences from a custom folder or URL: text box.

In iTerm2 3.3 on OSX the sequence is: iTerm2 menu, Preferences, General tab, Preferences subtab

How do I create a singleton service in Angular 2?

Just declare your service as provider in app.module.ts only.

It did the job for me.

providers: [Topic1Service,Topic2Service,...,TopicNService],

then either instanciate it using a constructor private parameter :

constructor(private topicService: TopicService) { }

or since if your service is used from html, the -prod option will claim:

Property 'topicService' is private and only accessible within class 'SomeComponent'.

add a member for your service and fill it with the instance recieved in the constructor:

export class SomeComponent {
  topicService: TopicService;
  constructor(private topicService: TopicService) { 
    this.topicService= topicService;
  }
}

Select first row in each GROUP BY group?

The solution is not very efficient as pointed by Erwin, because of presence of SubQs

select * from purchases p1 where total in
(select max(total) from purchases where p1.customer=customer) order by total desc;

Deployment error:Starting of Tomcat failed, the server port 8080 is already in use

Take a look on your running processes, it seems like your current Tomcat instance did not stop. It's still running and NetBeans tries to start a second Tomcat-instance. Thats the reason for your exception, you just have to stop the first instance, or deploy you code on the current running one

How to get the last five characters of a string using Substring() in C#?

If you can use extension methods, this will do it in a safe way regardless of string length:

public static string Right(this string text, int maxLength)
{
    if (string.IsNullOrEmpty(text) || maxLength <= 0)
    {
        return string.Empty;
    }

    if (maxLength < text.Length)
    {
        return text.Substring(text.Length - maxLength);
    }

    return text;
}

And to use it:

string sub = input.Right(5);

Converting between datetime, Timestamp and datetime64

I think there could be a more consolidated effort in an answer to better explain the relationship between Python's datetime module, numpy's datetime64/timedelta64 and pandas' Timestamp/Timedelta objects.

The datetime standard library of Python

The datetime standard library has four main objects

  • time - only time, measured in hours, minutes, seconds and microseconds
  • date - only year, month and day
  • datetime - All components of time and date
  • timedelta - An amount of time with maximum unit of days

Create these four objects

>>> import datetime
>>> datetime.time(hour=4, minute=3, second=10, microsecond=7199)
datetime.time(4, 3, 10, 7199)

>>> datetime.date(year=2017, month=10, day=24)
datetime.date(2017, 10, 24)

>>> datetime.datetime(year=2017, month=10, day=24, hour=4, minute=3, second=10, microsecond=7199)
datetime.datetime(2017, 10, 24, 4, 3, 10, 7199)

>>> datetime.timedelta(days=3, minutes = 55)
datetime.timedelta(3, 3300)

>>> # add timedelta to datetime
>>> datetime.timedelta(days=3, minutes = 55) + \
    datetime.datetime(year=2017, month=10, day=24, hour=4, minute=3, second=10, microsecond=7199)
datetime.datetime(2017, 10, 27, 4, 58, 10, 7199)

NumPy's datetime64 and timedelta64 objects

NumPy has no separate date and time objects, just a single datetime64 object to represent a single moment in time. The datetime module's datetime object has microsecond precision (one-millionth of a second). NumPy's datetime64 object allows you to set its precision from hours all the way to attoseconds (10 ^ -18). It's constructor is more flexible and can take a variety of inputs.

Construct NumPy's datetime64 and timedelta64 objects

Pass an integer with a string for the units. See all units here. It gets converted to that many units after the UNIX epoch: Jan 1, 1970

>>> np.datetime64(5, 'ns') 
numpy.datetime64('1970-01-01T00:00:00.000000005')

>>> np.datetime64(1508887504, 's')
numpy.datetime64('2017-10-24T23:25:04')

You can also use strings as long as they are in ISO 8601 format.

>>> np.datetime64('2017-10-24')
numpy.datetime64('2017-10-24')

Timedeltas have a single unit

>>> np.timedelta64(5, 'D') # 5 days
>>> np.timedelta64(10, 'h') 10 hours

Can also create them by subtracting two datetime64 objects

>>> np.datetime64('2017-10-24T05:30:45.67') - np.datetime64('2017-10-22T12:35:40.123')
numpy.timedelta64(147305547,'ms')

Pandas Timestamp and Timedelta build much more functionality on top of NumPy

A pandas Timestamp is a moment in time very similar to a datetime but with much more functionality. You can construct them with either pd.Timestamp or pd.to_datetime.

>>> pd.Timestamp(1239.1238934) #defautls to nanoseconds
Timestamp('1970-01-01 00:00:00.000001239')

>>> pd.Timestamp(1239.1238934, unit='D') # change units
Timestamp('1973-05-24 02:58:24.355200')

>>> pd.Timestamp('2017-10-24 05') # partial strings work
Timestamp('2017-10-24 05:00:00')

pd.to_datetime works very similarly (with a few more options) and can convert a list of strings into Timestamps.

>>> pd.to_datetime('2017-10-24 05')
Timestamp('2017-10-24 05:00:00')

>>> pd.to_datetime(['2017-1-1', '2017-1-2'])
DatetimeIndex(['2017-01-01', '2017-01-02'], dtype='datetime64[ns]', freq=None)

Converting Python datetime to datetime64 and Timestamp

>>> dt = datetime.datetime(year=2017, month=10, day=24, hour=4, 
                   minute=3, second=10, microsecond=7199)
>>> np.datetime64(dt)
numpy.datetime64('2017-10-24T04:03:10.007199')

>>> pd.Timestamp(dt) # or pd.to_datetime(dt)
Timestamp('2017-10-24 04:03:10.007199')

Converting numpy datetime64 to datetime and Timestamp

>>> dt64 = np.datetime64('2017-10-24 05:34:20.123456')
>>> unix_epoch = np.datetime64(0, 's')
>>> one_second = np.timedelta64(1, 's')
>>> seconds_since_epoch = (dt64 - unix_epoch) / one_second
>>> seconds_since_epoch
1508823260.123456

>>> datetime.datetime.utcfromtimestamp(seconds_since_epoch)
>>> datetime.datetime(2017, 10, 24, 5, 34, 20, 123456)

Convert to Timestamp

>>> pd.Timestamp(dt64)
Timestamp('2017-10-24 05:34:20.123456')

Convert from Timestamp to datetime and datetime64

This is quite easy as pandas timestamps are very powerful

>>> ts = pd.Timestamp('2017-10-24 04:24:33.654321')

>>> ts.to_pydatetime()   # Python's datetime
datetime.datetime(2017, 10, 24, 4, 24, 33, 654321)

>>> ts.to_datetime64()
numpy.datetime64('2017-10-24T04:24:33.654321000')

How do I call an Angular 2 pipe with multiple arguments?

Extended from : user3777549

Multi-value filter on one set of data(reference to title key only)

HTML

<div *ngFor='let item of items | filtermulti: [{title:["mr","ms"]},{first:["john"]}]' >
 Hello {{item.first}} !
</div>

filterMultiple

args.forEach(function (filterobj) {
    console.log(filterobj)
    let filterkey = Object.keys(filterobj)[0];
    let filtervalue = filterobj[filterkey];
    myobjects.forEach(function (objectToFilter) {

      if (!filtervalue.some(x=>x==objectToFilter[filterkey]) && filtervalue != "") {
        // object didn't match a filter value so remove it from array via filter
        returnobjects = returnobjects.filter(obj => obj !== objectToFilter);
      }
    })
  });

In Python, can I call the main() of an imported module?

The answer I was searching for was answered here: How to use python argparse with args other than sys.argv?

If main.py and parse_args() is written in this way, then the parsing can be done nicely

# main.py
import argparse
def parse_args():
    parser = argparse.ArgumentParser(description="")
    parser.add_argument('--input', default='my_input.txt')
    return parser

def main(args):
    print(args.input)

if __name__ == "__main__":
    parser = parse_args()
    args = parser.parse_args()
    main(args)

Then you can call main() and parse arguments with parser.parse_args(['--input', 'foobar.txt']) to it in another python script:

# temp.py
from main import main, parse_args
parser = parse_args()
args = parser.parse_args([]) # note the square bracket
# to overwrite default, use parser.parse_args(['--input', 'foobar.txt'])
print(args) # Namespace(input='my_input.txt')
main(args)

jquery drop down menu closing by clicking outside

how to have a click event outside of the dropdown menu so that it close the dropdown menu ? Heres the code

$(document).click(function (e) {
    e.stopPropagation();
    var container = $(".dropDown");

    //check if the clicked area is dropDown or not
    if (container.has(e.target).length === 0) {
        $('.subMenu').hide();
    }
})

Is it a good practice to place C++ definitions in header files?

Doesn't that really depends on the complexity of the system, and the in-house conventions?

At the moment I am working on a neural network simulator that is incredibly complex, and the accepted style that I am expected to use is:

Class definitions in classname.h
Class code in classnameCode.h
executable code in classname.cpp

This splits up the user-built simulations from the developer-built base classes, and works best in the situation.

However, I'd be surprised to see people do this in, say, a graphics application, or any other application that's purpose is not to provide users with a code base.

WinSCP: Permission denied. Error code: 3 Error message from server: Permission denied

You possibly do not have create permissions to the folder. So WinSCP fails to create a temporary file for the transfer.

You have two options:

How do I get the fragment identifier (value after hash #) from a URL?

Based on A.K's code, here is a Helper Function. JS Fiddle Here (http://jsfiddle.net/M5vsL/1/) ...

// Helper Method Defined Here.
(function (helper, $) {
    // This is now a utility function to "Get the Document Hash"
    helper.getDocumentHash = function (urlString) {
        var hashValue = "";

        if (urlString.indexOf('#') != -1) {
            hashValue = urlString.substring(parseInt(urlString.indexOf('#')) + 1);
        }
        return hashValue;
    };
})(this.helper = this.helper || {}, jQuery);

Convert timestamp to date in Oracle SQL

If you have milliseconds in the date string, you can use the following.

select TO_TIMESTAMP(SUBSTR('2020-09-10T09:37:28.378-07:00',1,23), 'YYYY-MM-DD"T"HH24:MI:SS:FF3')From Dual;

And then convert it to Date with:

select trunc(TO_TIMESTAMP(SUBSTR('2020-09-10T09:37:28.378-07:00',1,23), 'YYYY-MM-DD"T"HH24:MI:SS:FF3')) From Dual;

It worked for me, hope it will help you as well.

How to check if a variable is NULL, then set it with a MySQL stored procedure?

@last_run_time is a 9.4. User-Defined Variables and last_run_time datetime one 13.6.4.1. Local Variable DECLARE Syntax, are different variables.

Try: SELECT last_run_time;

UPDATE

Example:

/* CODE FOR DEMONSTRATION PURPOSES */
DELIMITER $$

CREATE PROCEDURE `sp_test`()
BEGIN
    DECLARE current_procedure_name CHAR(60) DEFAULT 'accounts_general';
    DECLARE last_run_time DATETIME DEFAULT NULL;
    DECLARE current_run_time DATETIME DEFAULT NOW();

    -- Define the last run time
    SET last_run_time := (SELECT MAX(runtime) FROM dynamo.runtimes WHERE procedure_name = current_procedure_name);

    -- if there is no last run time found then use yesterday as starting point
    IF(last_run_time IS NULL) THEN
        SET last_run_time := DATE_SUB(NOW(), INTERVAL 1 DAY);
    END IF;

    SELECT last_run_time;

    -- Insert variables in table2
    INSERT INTO table2 (col0, col1, col2) VALUES (current_procedure_name, last_run_time, current_run_time);
END$$

DELIMITER ;

No process is on the other end of the pipe (SQL Server 2012)

Yup, this error might as well be "something failed, good luck figuring out what" - In my case it was a wrong username. SQL Server 2019 RC1.

Difference Between One-to-Many, Many-to-One and Many-to-Many?

Looks like everyone is answering One-to-many vs. Many-to-many:

The difference between One-to-many, Many-to-one and Many-to-Many is:

One-to-many vs Many-to-one is a matter of perspective. Unidirectional vs Bidirectional will not affect the mapping but will make difference on how you can access your data.

  • In Many-to-one the many side will keep reference of the one side. A good example is "A State has Cities". In this case State is the one side and City is the many side. There will be a column state_id in the table cities.

In unidirectional, Person class will have List<Skill> skills but Skill will not have Person person. In bidirectional, both properties are added and it allows you to access a Person given a skill( i.e. skill.person).

  • In One-to-Many the one side will be our point of reference. For example, "A User has Addresses". In this case we might have three columns address_1_id, address_2_id and address_3_id or a look up table with multi column unique constraint on user_id on address_id.

In unidirectional, a User will have Address address. Bidirectional will have an additional List<User> users in the Address class.

  • In Many-to-Many members of each party can hold reference to arbitrary number of members of the other party. To achieve this a look up table is used. Example for this is the relationship between doctors and patients. A doctor can have many patients and vice versa.

How to sort a HashSet?

You can use Java 8 collectors and TreeSet

list.stream().collect(Collectors.toCollection(TreeSet::new))

Regular expression for matching HH:MM time format

Regular Expressions for Time

  • HH:MM 12-hour format, optional leading 0

      /^(0?[1-9]|1[0-2]):[0-5][0-9]$/
    
  • HH:MM 12-hour format, optional leading 0, mandatory meridiems (AM/PM)

      /((1[0-2]|0?[1-9]):([0-5][0-9]) ?([AaPp][Mm]))/
    
  • HH:MM 24-hour with leading 0

     /^(0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]$/
    
  • HH:MM 24-hour format, optional leading 0

     /^([0-9]|0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]$/
    
  • HH:MM:SS 24-hour format with leading 0

     /(?:[01]\d|2[0-3]):(?:[0-5]\d):(?:[0-5]\d)/
    

Reference and Demo

What's the right way to create a date in Java?

You can use SimpleDateFormat

SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
Date d = sdf.parse("21/12/2012");

But I don't know whether it should be considered more right than to use Calendar ...

AJAX post error : Refused to set unsafe header "Connection"

Remove these two lines:

xmlHttp.setRequestHeader("Content-length", params.length);
xmlHttp.setRequestHeader("Connection", "close");

XMLHttpRequest isn't allowed to set these headers, they are being set automatically by the browser. The reason is that by manipulating these headers you might be able to trick the server into accepting a second request through the same connection, one that wouldn't go through the usual security checks - that would be a security vulnerability in the browser.

How to add Class in <li> using wp_nav_menu() in Wordpress?

I added a class to easily implement menu arguments. So you can customize and include in your function like this:

include_once get_template_directory() . DIRECTORY_SEPARATOR . "your-directory" . DIRECTORY_SEPARATOR . "Menu.php";

<?php $menu = (new Menu('your-theme-location'))
            ->setMenuClass('your-menu')
            ->setMenuID('your-menu-id')
            ->setListClass('your-menu-class')
            ->setLinkClass('your-menu-link anchor') ?>
    
            // Print your menu
            <?php $menu->showMenu() ?>
<?php

class Menu
{
    private $args = [
        'theme_location' => '',
        'container' => '',
        'menu_id' => '',
        'menu_class' => '',
        'add_li_class' => '',
        'link_class' => ''
    ];

    public function __construct($themeLocation)
    {
        add_filter('nav_menu_css_class', [$this,'add_additional_class_on_li'], 1, 3);
        add_filter( 'nav_menu_link_attributes', [$this,'add_menu_link_class'], 1, 3 );

        $this->args['theme_location'] = $themeLocation;
    }

    public function wrapWithTag($tagName){
        $this->args['container'] = $tagName;
        return $this;
    }

    public function setMenuID($id)
    {
        $this->args['menu_id'] = $id;
        return $this;
    }

    public function setMenuClass($class)
    {
        $this->args['menu_class'] = $class;
        return $this;
    }

    public function setListClass($class)
    {
        $this->args['add_li_class'] = $class;
        return $this;
    }

    public function setLinkClass($class)
    {
        $this->args['link_class'] = $class;
        return $this;
    }

    public function showMenu()
    {
        return wp_nav_menu($this->args);
    }

    function add_additional_class_on_li($classes, $item, $args) {
        if(isset($args->add_li_class)) {
            $classes[] = $args->add_li_class;
        }
        return $classes;
    }

    function add_menu_link_class( $atts, $item, $args ) {
        if (property_exists($args, 'link_class')) {
            $atts['class'] = $args->link_class;
        }
        return $atts;
    }
}

Writing numerical values on the plot with Matplotlib

You can use the annotate command to place text annotations at any x and y values you want. To place them exactly at the data points you could do this

import numpy
from matplotlib import pyplot

x = numpy.arange(10)
y = numpy.array([5,3,4,2,7,5,4,6,3,2])

fig = pyplot.figure()
ax = fig.add_subplot(111)
ax.set_ylim(0,10)
pyplot.plot(x,y)
for i,j in zip(x,y):
    ax.annotate(str(j),xy=(i,j))

pyplot.show()

If you want the annotations offset a little, you could change the annotate line to something like

ax.annotate(str(j),xy=(i,j+0.5))

Can I use an HTML input type "date" to collect only a year?

There is input type month in HTML5 which allows to select month and year. Month selector works with autocomplete.

Check the example in JSFiddle.

<!DOCTYPE html>
<html>
<body>
    <header>
        <h1>Select a month below</h1>
    </header>
    Month example
    <input type="month" />
</body>
</html>

Angular HTTP GET with TypeScript error http.get(...).map is not a function in [null]

import { map } from 'rxjs/operators';

this works for me in angular 8

How get value from URL

Website URL:

http://www.example.com/?id=2

Code:

$id = intval($_GET['id']);
$results = mysql_query("SELECT * FROM next WHERE id=$id");    
while ($row = mysql_fetch_array($results))     
{       
    $url = $row['url'];
    echo $url; //Outputs: 2
}

Bundler: Command not found

I got this error rbenv: bundle: command not found after cloning an old rails project I had built a couple on months ago. here is how I went about it: To install a specific version of bundler or just run the following command to install the latest available bundler:

run gem install bundler

then I installed the exact version of bundler I wanted with this command:

$ gem install bundler -v "$(grep -A 1 "BUNDLED WITH" Gemfile.lock | tail -n 1)"

[check this article for more details](https://www.aloucaslabs.com/miniposts/rbenv-bundle-command-not-found#:~:text=When%20you%20get%20the%20rbenv,to%20install%20the%20Bundler%20gem check this article for more details

get the listen to work by issuing this command

echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p

Owl Carousel, making custom navigation

If you want to use your own custom navigation elements,

For Owl Carousel 1

var owl = $('.owl-carousel');
owl.owlCarousel();
// Go to the next item
$('.customNextBtn').click(function() {
    owl.trigger('owl.prev');
})
// Go to the previous item
$('.customPrevBtn').click(function() {
    owl.trigger('owl.next');
})

For Owl Carousel 2

var owl = $('.owl-carousel');
owl.owlCarousel();
// Go to the next item
$('.customNextBtn').click(function() {
    owl.trigger('next.owl.carousel');
})
// Go to the previous item
$('.customPrevBtn').click(function() {
    // With optional speed parameter
    // Parameters has to be in square bracket '[]'
    owl.trigger('prev.owl.carousel', [300]);
})

Why is the gets function so dangerous that it should not be used?

You can't remove API functions without breaking the API. If you would, many applications would no longer compile or run at all.

This is the reason that one reference gives:

Reading a line that overflows the array pointed to by s results in undefined behavior. The use of fgets() is recommended.

How to get the PYTHONPATH in shell?

You can also try this:

Python 2.x:
python -c "import sys; print '\n'.join(sys.path)"

Python 3.x:
python3 -c "import sys; print('\n'.join(sys.path))"

The output will be more readable and clean, like so:

/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python27.zip /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7 /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-old /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-dynload /Library/Python/2.7/site-packages /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/PyObjC

java.lang.IllegalStateException: Error processing condition on org.springframework.boot.autoconfigure.jdbc.JndiDataSourceAutoConfiguration

In my case I had created a SB app from the SB Initializer and had included a fair number of deps in it to other things. I went in and commented out the refs to them in the build.gradle file and so was left with:

implementation 'org.springframework.boot:spring-boot-starter-hateoas'
compileOnly 'org.projectlombok:lombok'
developmentOnly 'org.springframework.boot:spring-boot-devtools'
runtimeOnly 'org.hsqldb:hsqldb'
runtimeOnly 'org.postgresql:postgresql'
annotationProcessor 'org.springframework.boot:spring-boot-configuration-processor'
annotationProcessor 'org.projectlombok:lombok'
testImplementation 'org.springframework.boot:spring-boot-starter-test'
testImplementation 'org.springframework.restdocs:spring-restdocs-mockmvc'

as deps. Then my bare-bones SB app was able to build and get running successfully. As I go to try to do things that may need those commented-out libs I will add them back and see what breaks.

Change the maximum upload file size

I had the same problem and i created a .user.ini file and put it in the directory in which the upload script was located. Than inside that file i set these these two values:

  upload_max_filesize = 40M

  post_max_size = 40M

and it worked great for me!

What is the maximum number of edges in a directed graph with n nodes?

The correct answer is n*(n-1)/2. Each edge has been counted twice, hence the division by 2. A complete graph has the maximum number of edges, which is given by n choose 2 = n*(n-1)/2.

How to completely remove a dialog on close

$(this).dialog('destroy').remove()

This will destroy the dialog and then remove the div that was "hosting" the dialog completely from the DOM

Get commit list between tags in git

FYI:

git log tagA...tagB

provides standard log output in a range.

How to export JavaScript array info to csv (on client side)?

Old question with many good answers, but here is another simple option that relies on two popular libraries to get it done. Some answers mention Papa Parse but roll their own solution for the download part. Combining Papa Parse and FileSaver.js, you can try the following:

const dataString = Papa.unparse(data, config);
const blob = new Blob([dataString], { type: 'text/csv;charset=utf-8' });
FileSaver.saveAs(blob, 'myfile.csv');

The config options for unparse are described here.

Abort Ajax requests using jQuery

Save the calls you make in an array, then call xhr.abort() on each.

HUGE CAVEAT: You can abort a request, but that's only the client side. The server side could still be processing the request. If you are using something like PHP or ASP with session data, the session data is locked until the ajax has finished. So, to allow the user to continue browsing the website, you have to call session_write_close(). This saves the session and unlocks it so that other pages waiting to continue will proceed. Without this, several pages can be waiting for the lock to be removed.

Can I remove the URL from my print css, so the web address doesn't print?

If I understand you correctly, you talk about the page headers and footers. They are printed by the browser. They are not part of your HTML content, so you can't influence them directly.

Show your users how to disable headers and footers in the «Page setup...» dialog.

How do I count a JavaScript object's attributes?

 var miobj = [
  {"padreid":"0", "sw":"0", "dtip":"UNO", "datos":[]},
  {"padreid":"1", "sw":"0", "dtip":"DOS", "datos":[]}
 ];
 alert(miobj.length) //=== 2

but

 alert(miobj[0].length) //=== undefined

this function is very good

Object.prototype.count = function () {
    var count = 0;
    for(var prop in this) {
        if(this.hasOwnProperty(prop))
            count = count + 1;
    }
    return count;
}

alert(miobj.count()) // === 2
alert(miobj[0].count()) // === 4

HTML5 live streaming

Firstly you need to setup a media streaming server. You can use Wowza, red5 or nginx-rtmp-module. Read their documentation and setup on OS you want. All the engine are support HLS (Http Live Stream protocol that was developed by Apple). You should read documentation for config. Example with nginx-rtmp-module:

rtmp {
    server {
        listen 1935; # Listen on standard RTMP port
        chunk_size 4000;

        application show {
            live on;
            # Turn on HLS
            hls on;
            hls_path /mnt/hls/;
            hls_fragment 3;
            hls_playlist_length 60;
            # disable consuming the stream from nginx as rtmp
            deny play all;
        }
    }
} 

server {
    listen 8080;

    location /hls {
        # Disable cache
        add_header Cache-Control no-cache;

        # CORS setup
        add_header 'Access-Control-Allow-Origin' '*' always;
        add_header 'Access-Control-Expose-Headers' 'Content-Length,Content-Range';
        add_header 'Access-Control-Allow-Headers' 'Range';

        # allow CORS preflight requests
        if ($request_method = 'OPTIONS') {
            add_header 'Access-Control-Allow-Origin' '*';
            add_header 'Access-Control-Allow-Headers' 'Range';
            add_header 'Access-Control-Max-Age' 1728000;
            add_header 'Content-Type' 'text/plain charset=UTF-8';
            add_header 'Content-Length' 0;
            return 204;
        }

        types {
            application/vnd.apple.mpegurl m3u8;
            video/mp2t ts;
        }

        root /mnt/;
    }
}

After server was setup and configuration successful. you must use some rtmp encoder software (OBS, wirecast ...) for start streaming like youtube or twitchtv.

In client side (browser in your case) you can use Videojs or JWplayer to play video for end user. You can do something like below for Videojs:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Live Streaming</title>
    <link href="//vjs.zencdn.net/5.8/video-js.min.css" rel="stylesheet">
    <script src="//vjs.zencdn.net/5.8/video.min.js"></script>
</head>
<body>
<video id="player" class="video-js vjs-default-skin" height="360" width="640" controls preload="none">
    <source src="http://localhost:8080/hls/stream.m3u8" type="application/x-mpegURL" />
</video>
<script>
    var player = videojs('#player');
</script>
</body>
</html>

You don't need to add others plugin like flash (because we use HLS not rtmp). This player can work well cross browser with out flash.

When to use SELECT ... FOR UPDATE?

Short answers:

Q1: Yes.

Q2: Doesn't matter which you use.

Long answer:

A select ... for update will (as it implies) select certain rows but also lock them as if they have already been updated by the current transaction (or as if the identity update had been performed). This allows you to update them again in the current transaction and then commit, without another transaction being able to modify these rows in any way.

Another way of looking at it, it is as if the following two statements are executed atomically:

select * from my_table where my_condition;

update my_table set my_column = my_column where my_condition;

Since the rows affected by my_condition are locked, no other transaction can modify them in any way, and hence, transaction isolation level makes no difference here.

Note also that transaction isolation level is independent of locking: setting a different isolation level doesn't allow you to get around locking and update rows in a different transaction that are locked by your transaction.

What transaction isolation levels do guarantee (at different levels) is the consistency of data while transactions are in progress.

Android Studio Emulator and "Process finished with exit code 0"

I also faced the same error. After a few hours I figured it out.

I hope it helps you :

Go to Tools ==> SDK Menager ==>Android SDK

(Appearange&Behavior=>System settings=>Android SDK)==>SDK Tools==>Intel x86 Emulator Accelerator(install this).

It will solve your problem.I hope it helps.

You can look at pictures which you must install