Programs & Examples On #Wsod

White Screen Of Death

Magento How to debug blank white screen

This is how I got it corrected(Hope will help you guys):

  1. Use the following code in your index.php file

    ini_set('error_reporting', E_ERROR);
    register_shutdown_function("fatal_handler");
    function fatal_handler() {
        $error = error_get_last();
        echo("<pre>");
        print_r($error);
    }
    
  2. In my case it tolde me that error/503.php was unavailable.

3.The issue was with testimonial extension I used(http://www.magentocommerce.com/magento-connect/magebuzz-free-testimonial.html)

  1. I deleted the testimonial.xml file in my app/etc/modules/testimoanial.xml.
  2. delete “maintenance.flag" file.

Simple example of threading in C++

It largely depends on the library you decide to use. For instance, if you use the wxWidgets library, the creation of a thread would look like this:

class RThread : public wxThread {

public:
    RThread()
        : wxThread(wxTHREAD_JOINABLE){
    }
private:
    RThread(const RThread &copy);

public:
    void *Entry(void){
        //Do...

        return 0;
    }

};

wxThread *CreateThread() {
    //Create thread
    wxThread *_hThread = new RThread();

    //Start thread
    _hThread->Create();
    _hThread->Run();

    return _hThread;
}

If your main thread calls the CreateThread method, you'll create a new thread that will start executing the code in your "Entry" method. You'll have to keep a reference to the thread in most cases to join or stop it. More info here: wxThread documentation

How to find the logs on android studio?

You could open Messages or Event Log tool window to see your log. In addition to that if you want to see device log then you could open Logcat tool window to view your log : View > Tool Windows > Logcat enter image description here

jQuery select child element by class with unknown path

Try this

$('#thisElement .classToSelect').each(function(i){
         // do stuff
});

Hope it will help

How to set multiple commands in one yaml file with Kubernetes?

Just to bring another possible option, secrets can be used as they are presented to the pod as volumes:

Secret example:

apiVersion: v1
kind: Secret 
metadata:
  name: secret-script
type: Opaque
data:
  script_text: <<your script in b64>>

Yaml extract:

....
containers:
    - name: container-name
      image: image-name
      command: ["/bin/bash", "/your_script.sh"]
      volumeMounts:
        - name: vsecret-script
          mountPath: /your_script.sh
          subPath: script_text
....
  volumes:
    - name: vsecret-script
      secret:
        secretName: secret-script

I know many will argue this is not what secrets must be used for, but it is an option.

Understanding Apache's access log

You seem to be using the combined log format.

LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-agent}i\"" combined

  • %h is the remote host (ie the client IP)
  • %l is the identity of the user determined by identd (not usually used since not reliable)
  • %u is the user name determined by HTTP authentication
  • %t is the time the request was received.
  • %r is the request line from the client. ("GET / HTTP/1.0")
  • %>s is the status code sent from the server to the client (200, 404 etc.)
  • %b is the size of the response to the client (in bytes)
  • Referer is the Referer header of the HTTP request (containing the URL of the page from which this request was initiated) if any is present, and "-" otherwise.
  • User-agent is the browser identification string.

The complete(?) list of formatters can be found here. The same section of the documentation also lists other common log formats; readers whose logs don't look quite like this one may find the pattern their Apache configuration is using listed there.

How can I pass a class member function as a callback?

A pointer to a class member function is not the same as a pointer to a function. A class member takes an implicit extra argument (the this pointer), and uses a different calling convention.

If your API expects a nonmember callback function, that's what you have to pass to it.

Generating Random Passwords

This is a lot larger, but I think it looks a little more comprehensive: http://www.obviex.com/Samples/Password.aspx

///////////////////////////////////////////////////////////////////////////////
// SAMPLE: Generates random password, which complies with the strong password
//         rules and does not contain ambiguous characters.
//
// To run this sample, create a new Visual C# project using the Console
// Application template and replace the contents of the Class1.cs file with
// the code below.
//
// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
// EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
// 
// Copyright (C) 2004 Obviex(TM). All rights reserved.
// 
using System;
using System.Security.Cryptography;

/// <summary>
/// This class can generate random passwords, which do not include ambiguous 
/// characters, such as I, l, and 1. The generated password will be made of
/// 7-bit ASCII symbols. Every four characters will include one lower case
/// character, one upper case character, one number, and one special symbol
/// (such as '%') in a random order. The password will always start with an
/// alpha-numeric character; it will not start with a special symbol (we do
/// this because some back-end systems do not like certain special
/// characters in the first position).
/// </summary>
public class RandomPassword
{
    // Define default min and max password lengths.
    private static int DEFAULT_MIN_PASSWORD_LENGTH  = 8;
    private static int DEFAULT_MAX_PASSWORD_LENGTH  = 10;

    // Define supported password characters divided into groups.
    // You can add (or remove) characters to (from) these groups.
    private static string PASSWORD_CHARS_LCASE  = "abcdefgijkmnopqrstwxyz";
    private static string PASSWORD_CHARS_UCASE  = "ABCDEFGHJKLMNPQRSTWXYZ";
    private static string PASSWORD_CHARS_NUMERIC= "23456789";
    private static string PASSWORD_CHARS_SPECIAL= "*$-+?_&=!%{}/";

    /// <summary>
    /// Generates a random password.
    /// </summary>
    /// <returns>
    /// Randomly generated password.
    /// </returns>
    /// <remarks>
    /// The length of the generated password will be determined at
    /// random. It will be no shorter than the minimum default and
    /// no longer than maximum default.
    /// </remarks>
    public static string Generate()
    {
        return Generate(DEFAULT_MIN_PASSWORD_LENGTH, 
                        DEFAULT_MAX_PASSWORD_LENGTH);
    }

    /// <summary>
    /// Generates a random password of the exact length.
    /// </summary>
    /// <param name="length">
    /// Exact password length.
    /// </param>
    /// <returns>
    /// Randomly generated password.
    /// </returns>
    public static string Generate(int length)
    {
        return Generate(length, length);
    }

    /// <summary>
    /// Generates a random password.
    /// </summary>
    /// <param name="minLength">
    /// Minimum password length.
    /// </param>
    /// <param name="maxLength">
    /// Maximum password length.
    /// </param>
    /// <returns>
    /// Randomly generated password.
    /// </returns>
    /// <remarks>
    /// The length of the generated password will be determined at
    /// random and it will fall with the range determined by the
    /// function parameters.
    /// </remarks>
    public static string Generate(int   minLength,
                                  int   maxLength)
    {
        // Make sure that input parameters are valid.
        if (minLength <= 0 || maxLength <= 0 || minLength > maxLength)
            return null;

        // Create a local array containing supported password characters
        // grouped by types. You can remove character groups from this
        // array, but doing so will weaken the password strength.
        char[][] charGroups = new char[][] 
        {
            PASSWORD_CHARS_LCASE.ToCharArray(),
            PASSWORD_CHARS_UCASE.ToCharArray(),
            PASSWORD_CHARS_NUMERIC.ToCharArray(),
            PASSWORD_CHARS_SPECIAL.ToCharArray()
        };

        // Use this array to track the number of unused characters in each
        // character group.
        int[] charsLeftInGroup = new int[charGroups.Length];

        // Initially, all characters in each group are not used.
        for (int i=0; i<charsLeftInGroup.Length; i++)
            charsLeftInGroup[i] = charGroups[i].Length;

        // Use this array to track (iterate through) unused character groups.
        int[] leftGroupsOrder = new int[charGroups.Length];

        // Initially, all character groups are not used.
        for (int i=0; i<leftGroupsOrder.Length; i++)
            leftGroupsOrder[i] = i;

        // Because we cannot use the default randomizer, which is based on the
        // current time (it will produce the same "random" number within a
        // second), we will use a random number generator to seed the
        // randomizer.

        // Use a 4-byte array to fill it with random bytes and convert it then
        // to an integer value.
        byte[] randomBytes = new byte[4];

        // Generate 4 random bytes.
        RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
        rng.GetBytes(randomBytes);

        // Convert 4 bytes into a 32-bit integer value.
        int seed = BitConverter.ToInt32(randomBytes, 0);

        // Now, this is real randomization.
        Random  random  = new Random(seed);

        // This array will hold password characters.
        char[] password = null;

        // Allocate appropriate memory for the password.
        if (minLength < maxLength)
            password = new char[random.Next(minLength, maxLength+1)];
        else
            password = new char[minLength];

        // Index of the next character to be added to password.
        int nextCharIdx;

        // Index of the next character group to be processed.
        int nextGroupIdx;

        // Index which will be used to track not processed character groups.
        int nextLeftGroupsOrderIdx;

        // Index of the last non-processed character in a group.
        int lastCharIdx;

        // Index of the last non-processed group.
        int lastLeftGroupsOrderIdx = leftGroupsOrder.Length - 1;

        // Generate password characters one at a time.
        for (int i=0; i<password.Length; i++)
        {
            // If only one character group remained unprocessed, process it;
            // otherwise, pick a random character group from the unprocessed
            // group list. To allow a special character to appear in the
            // first position, increment the second parameter of the Next
            // function call by one, i.e. lastLeftGroupsOrderIdx + 1.
            if (lastLeftGroupsOrderIdx == 0)
                nextLeftGroupsOrderIdx = 0;
            else
                nextLeftGroupsOrderIdx = random.Next(0, 
                                                     lastLeftGroupsOrderIdx);

            // Get the actual index of the character group, from which we will
            // pick the next character.
            nextGroupIdx = leftGroupsOrder[nextLeftGroupsOrderIdx];

            // Get the index of the last unprocessed characters in this group.
            lastCharIdx = charsLeftInGroup[nextGroupIdx] - 1;

            // If only one unprocessed character is left, pick it; otherwise,
            // get a random character from the unused character list.
            if (lastCharIdx == 0)
                nextCharIdx = 0;
            else
                nextCharIdx = random.Next(0, lastCharIdx+1);

            // Add this character to the password.
            password[i] = charGroups[nextGroupIdx][nextCharIdx];

            // If we processed the last character in this group, start over.
            if (lastCharIdx == 0)
                charsLeftInGroup[nextGroupIdx] = 
                                          charGroups[nextGroupIdx].Length;
            // There are more unprocessed characters left.
            else
            {
                // Swap processed character with the last unprocessed character
                // so that we don't pick it until we process all characters in
                // this group.
                if (lastCharIdx != nextCharIdx)
                {
                    char temp = charGroups[nextGroupIdx][lastCharIdx];
                    charGroups[nextGroupIdx][lastCharIdx] = 
                                charGroups[nextGroupIdx][nextCharIdx];
                    charGroups[nextGroupIdx][nextCharIdx] = temp;
                }
                // Decrement the number of unprocessed characters in
                // this group.
                charsLeftInGroup[nextGroupIdx]--;
            }

            // If we processed the last group, start all over.
            if (lastLeftGroupsOrderIdx == 0)
                lastLeftGroupsOrderIdx = leftGroupsOrder.Length - 1;
            // There are more unprocessed groups left.
            else
            {
                // Swap processed group with the last unprocessed group
                // so that we don't pick it until we process all groups.
                if (lastLeftGroupsOrderIdx != nextLeftGroupsOrderIdx)
                {
                    int temp = leftGroupsOrder[lastLeftGroupsOrderIdx];
                    leftGroupsOrder[lastLeftGroupsOrderIdx] = 
                                leftGroupsOrder[nextLeftGroupsOrderIdx];
                    leftGroupsOrder[nextLeftGroupsOrderIdx] = temp;
                }
                // Decrement the number of unprocessed groups.
                lastLeftGroupsOrderIdx--;
            }
        }

        // Convert password characters into a string and return the result.
        return new string(password);
     }
}

/// <summary>
/// Illustrates the use of the RandomPassword class.
/// </summary>
public class RandomPasswordTest
{
    /// <summary>
    /// The main entry point for the application.
    /// </summary>
    [STAThread]
    static void Main(string[] args)
    {
        // Print 100 randomly generated passwords (8-to-10 char long).
        for (int i=0; i<100; i++)
            Console.WriteLine(RandomPassword.Generate(8, 10));
    }
}
//
// END OF FILE
///////////////////////////////////////////////////////////////////////////////

Keep SSH session alive

putty settings

FYI Putty Users can set the options here

How can I convert a string to boolean in JavaScript?

In nodejs by using node-boolify it is possible

Boolean Conversion Results

Boolify(true); //true
Boolify('true'); //true
Boolify('TRUE'); //null
Boolify(1); //true
Boolify(2); //null
Boolify(false); //false
Boolify('false'); //false
Boolify('FALSE'); //null
Boolify(0); //false
Boolify(null); //null
Boolify(undefined); //null
Boolify(); //null
Boolify(''); //null

Firebase Permission Denied

OK, but you don`t want to open the whole realtime database! You need something like this.

{
  /* Visit https://firebase.google.com/docs/database/security to learn more about security rules. */
  "rules": {
    ".read": "auth.uid !=null",
    ".write": "auth.uid !=null"
  }
}

or

{
  "rules": {
    "users": {
      "$uid": {
        ".write": "$uid === auth.uid"
      }
    }
  }
}

How to split large text file in windows?

Of course there is! Win CMD can do a lot more than just split text files :)

Split a text file into separate files of 'max' lines each:

Split text file (max lines each):
: Initialize
set input=file.txt
set max=10000

set /a line=1 >nul
set /a file=1 >nul
set out=!file!_%input%
set /a max+=1 >nul

echo Number of lines in %input%:
find /c /v "" < %input%

: Split file
for /f "tokens=* delims=[" %i in ('type "%input%" ^| find /v /n ""') do (

if !line!==%max% (
set /a line=1 >nul
set /a file+=1 >nul
set out=!file!_%input%
echo Writing file: !out!
)

REM Write next file
set a=%i
set a=!a:*]=]!
echo:!a:~1!>>out!
set /a line+=1 >nul
)

If above code hangs or crashes, this example code splits files faster (by writing data to intermediate files instead of keeping everything in memory):

eg. To split a file with 7,600 lines into smaller files of maximum 3000 lines.

  1. Generate regexp string/pattern files with set command to be fed to /g flag of findstr

list1.txt

\[[0-9]\]
\[[0-9][0-9]\]
\[[0-9][0-9][0-9]\]
\[[0-2][0-9][0-9][0-9]\]

list2.txt

\[[3-5][0-9][0-9][0-9]\]

list3.txt

\[[6-9][0-9][0-9][0-9]\]

  1. Split the file into smaller files:
type "%input%" | find /v /n "" | findstr /b /r /g:list1.txt > file1.txt
type "%input%" | find /v /n "" | findstr /b /r /g:list2.txt > file2.txt
type "%input%" | find /v /n "" | findstr /b /r /g:list3.txt > file3.txt
  1. remove prefixed line numbers for each file split:
    eg. for the 1st file:
for /f "tokens=* delims=[" %i in ('type "%cd%\file1.txt"') do (
set a=%i
set a=!a:*]=]!
echo:!a:~1!>>file_1.txt)

Notes:
Works with leading whitespace, blank lines & whitespace lines.

Tested on Win 10 x64 CMD, on 4.4GB text file, 5651982 lines.

MySQL COUNT DISTINCT

Overall

SELECT
       COUNT(DISTINCT `site_id`) as distinct_sites
  FROM `cp_visits`
 WHERE ts >= DATE_SUB(NOW(), INTERVAL 1 DAY)

Or per site

  SELECT
         `site_id` as site,
         COUNT(DISTINCT `user_id`) as distinct_users_per_site
    FROM `cp_visits`
   WHERE ts >= DATE_SUB(NOW(), INTERVAL 1 DAY)
GROUP BY `site_id`

Having the time column in the result doesn't make sense - since you are aggregating the rows, showing one particular time is irrelevant, unless it is the min or max you are after.

How to make script execution wait until jquery is loaded

Let's expand defer() from Dario to be more reusable.

function defer(toWaitFor, method) {
    if (window[toWaitFor]) {
        method();
    } else {
        setTimeout(function () { defer(toWaitFor, method) }, 50);
    }
}

Which is then run:

function waitFor() {
    defer('jQuery', () => {console.log('jq done')});
    defer('utag', () => {console.log('utag done')});
}

How to check the multiple permission at single request in Android M?

First initialize permission request code

public  static final int PERMISSIONS_MULTIPLE_REQUEST = 123;

Check android version

 private void checkAndroidVersion() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        checkPermission();

    } else {
        // write your logic here
    }

}

check multiple permission code

 private void checkPermission() {
    if (ContextCompat.checkSelfPermission(getActivity(),
            Manifest.permission.READ_EXTERNAL_STORAGE) + ContextCompat
            .checkSelfPermission(getActivity(),
                    Manifest.permission.CAMERA)
            != PackageManager.PERMISSION_GRANTED) {

        if (ActivityCompat.shouldShowRequestPermissionRationale
                (getActivity(), Manifest.permission.READ_EXTERNAL_STORAGE) ||
                ActivityCompat.shouldShowRequestPermissionRationale
                        (getActivity(), Manifest.permission.CAMERA)) {

      Snackbar.make(getActivity().findViewById(android.R.id.content),
                    "Please Grant Permissions to upload profile photo",
                    Snackbar.LENGTH_INDEFINITE).setAction("ENABLE",
                    new View.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                            requestPermissions(
                                    new String[]{Manifest.permission
                                            .READ_EXTERNAL_STORAGE, Manifest.permission.CAMERA},
                                    PERMISSIONS_MULTIPLE_REQUEST);
                        }
                    }).show();
        } else {
            requestPermissions(
                    new String[]{Manifest.permission
                            .READ_EXTERNAL_STORAGE, Manifest.permission.CAMERA},
                    PERMISSIONS_MULTIPLE_REQUEST);
        }
    } else {
        // write your logic code if permission already granted
    }
}

call back method after grant permission by user

@Override
public void onRequestPermissionsResult(int requestCode,
                                       @NonNull String[] permissions, @NonNull int[] grantResults) {

    switch (requestCode) {
        case PERMISSIONS_MULTIPLE_REQUEST:
            if (grantResults.length > 0) {
               boolean cameraPermission = grantResults[1] == PackageManager.PERMISSION_GRANTED;
               boolean readExternalFile = grantResults[0] == PackageManager.PERMISSION_GRANTED;

                if(cameraPermission && readExternalFile)
                {
                    // write your logic here 
                } else {
                    Snackbar.make(getActivity().findViewById(android.R.id.content),
                        "Please Grant Permissions to upload profile photo",
                        Snackbar.LENGTH_INDEFINITE).setAction("ENABLE",
                        new View.OnClickListener() {
                            @Override
                            public void onClick(View v) {
                                requestPermissions(
                                        new String[]{Manifest.permission
                                                .READ_EXTERNAL_STORAGE, Manifest.permission.CAMERA},
                                        PERMISSIONS_MULTIPLE_REQUEST);
                            }
                        }).show();
                }
           }
           break;
    }
}

Unable to create a constant value of type Only primitive types or enumeration types are supported in this context

This cannot work because ppCombined is a collection of objects in memory and you cannot join a set of data in the database with another set of data that is in memory. You can try instead to extract the filtered items personProtocol of the ppCombined collection in memory after you have retrieved the other properties from the database:

var persons = db.Favorites
    .Where(f => f.userId == userId)
    .Join(db.Person, f => f.personId, p => p.personId, (f, p) =>
        new // anonymous object
        {
            personId = p.personId,
            addressId = p.addressId,   
            favoriteId = f.favoriteId,
        })
    .AsEnumerable() // database query ends here, the rest is a query in memory
    .Select(x =>
        new PersonDTO
        {
            personId = x.personId,
            addressId = x.addressId,   
            favoriteId = x.favoriteId,
            personProtocol = ppCombined
                .Where(p => p.personId == x.personId)
                .Select(p => new PersonProtocol
                {
                    personProtocolId = p.personProtocolId,
                    activateDt = p.activateDt,
                    personId = p.personId
                })
                .ToList()
        });

Select an Option from the Right-Click Menu in Selenium Webdriver - Java

Using python webdriver right click operation

from selenium import webdriver

from selenium.webdriver import ActionChains

import time

driver = webdriver.Chrome()

driver.get("https://swisnl.github.io/jQuery-contextMenu/demo.html")
button=driver.find_element_by_xpath("//body[@class='wy-body-for-nav']")

action=ActionChains(driver)
action.context_click(button).perform()

TCP vs UDP on video stream

There are some use cases suitable to UDP transport and others suitable to TCP transport.

The use case also dictates encoding settings for the video. When broadcasting soccer match focus is on quality and for video conference focus is on latency.

When using multicast to deliver video to your customers then UDP is used.

Requirement for multicast is expensive networking hardware between broadcasting server and customer. In practice this means if your company owns network infrastructure you can use UDP and multicast for live video streaming. Even then quality-of-service is also implemented to mark video packets and prioritize them so no packet loss happens.

Multicast will simplify broadcasting software because network hardware will handle distributing packets to customers. Customers subscribe to multicast channels and network will reconfigure to route packets to new subscriber. By default all channels are available to all customers and can be optimally routed.

This workflow places dificulty on authorization process. Network hardware does not differentiate subscribed users from other users. Solution to authorization is in encrypting video content and enabling decryption in player software when subscription is valid.

Unicast (TCP) workflow allows server to check client's credentials and only allow valid subscriptions. Even allow only certain number of simultaneous connections.

Multicast is not enabled over internet.

For delivering video over internet TCP must be used. When UDP is used developers end up re-implementing packet re-transmission, for eg. Bittorrent p2p live protocol.

"If you use TCP, the OS must buffer the unacknowledged segments for every client. This is undesirable, particularly in the case of live events".

This buffer must exist in some form. Same is true for jitter buffer on player side. It is called "socket buffer" and server software can know when this buffer is full and discard proper video frames for live streams. It is better to use unicast/TCP method because server software can implement proper frame dropping logic. Random missing packets in UDP case will just create bad user experience. like in this video: http://tinypic.com/r/2qn89xz/9

"IP multicast significantly reduces video bandwidth requirements for large audiences"

This is true for private networks, Multicast is not enabled over internet.

"Note that if TCP loses too many packets, the connection dies; thus, UDP gives you much more control for this application since UDP doesn't care about network transport layer drops."

UDP also doesn't care about dropping entire frames or group-of-frames so it does not give any more control over user experience.

"Usually a video stream is somewhat fault tolerant"

Encoded video is not fault tolerant. When transmitted over unreliable transport then forward error correction is added to video container. Good example is MPEG-TS container used in satellite video broadcast that carry several audio, video, EPG, etc. streams. This is necessary as satellite link is not duplex communication, meaning receiver can't request re-transmission of lost packets.

When you have duplex communication available it is always better to re-transmit data only to clients having packet loss then to include overhead of forward-error-correction in stream sent to all clients.

In any case lost packets are unacceptable. Dropped frames are ok in exceptional cases when bandwidth is hindered.

The result of missing packets are artifacts like this one: artifacts

Some decoders can break on streams missing packets in critical places.

Truststore and Keystore Definitions

You may also be interested in the write-up from Sun, as part of the standard JSSE documentation:

http://docs.oracle.com/javase/8/docs/technotes/guides/security/jsse/JSSERefGuide.html#Stores

Typically, the trust store is used to store only public keys, for verification purposes, such as with X.509 authentication. For manageability purposes, it's quite common for admins or developers to simply conflate the two into a single store.

What happened to Lodash _.pluck?

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

Here's an alternative using ES6 JavaScript:

clips.map(clip => clip.id)

Left Join without duplicate rows from left table

Try an OUTER APPLY

SELECT 
    C.Content_ID,
    C.Content_Title,
    C.Content_DatePublished,
    M.Media_Id
FROM 
    tbl_Contents C
    OUTER APPLY
    (
        SELECT TOP 1 *
        FROM tbl_Media M 
        WHERE M.Content_Id = C.Content_Id 
    ) m
ORDER BY 
    C.Content_DatePublished ASC

Alternatively, you could GROUP BY the results

SELECT 
    C.Content_ID,
    C.Content_Title,
    C.Content_DatePublished,
    M.Media_Id
FROM 
    tbl_Contents C
    LEFT OUTER JOIN tbl_Media M ON M.Content_Id = C.Content_Id 
GROUP BY
    C.Content_ID,
    C.Content_Title,
    C.Content_DatePublished,
    M.Media_Id
ORDER BY
    C.Content_DatePublished ASC

The OUTER APPLY selects a single row (or none) that matches each row from the left table.

The GROUP BY performs the entire join, but then collapses the final result rows on the provided columns.

Calculating the distance between 2 points

Something like this in c# would probably do the job. Just make sure you are passing consistent units (If one point is in meters, make sure the second is also in meters)

private static double GetDistance(double x1, double y1, double x2, double y2)
{
   return Math.Sqrt(Math.Pow((x2 - x1), 2) + Math.Pow((y2 - y1), 2));
}

Called like so:

double distance = GetDistance(x1, y1, x2, y2)
if(distance <= 5)
{
   //Do stuff
}

Javascript get the text value of a column from a particular row of an html table

document.getElementById("tblBlah").rows[i].columns[j].innerHTML;

Should be:

document.getElementById("tblBlah").rows[i].cells[j].innerHTML;

But I get the distinct impression that the row/cell you need is the one clicked by the user. If so, the simplest way to achieve this would be attaching an event to the cells in your table:

function alertInnerHTML(e)
{
    e = e || window.event;//IE
    alert(this.innerHTML);
}

var theTbl = document.getElementById('tblBlah');
for(var i=0;i<theTbl.length;i++)
{
    for(var j=0;j<theTbl.rows[i].cells.length;j++)
    {
        theTbl.rows[i].cells[j].onclick = alertInnerHTML;
    }
}

That makes all table cells clickable, and alert it's innerHTML. The event object will be passed to the alertInnerHTML function, in which the this object will be a reference to the cell that was clicked. The event object offers you tons of neat tricks on how you want the click event to behave if, say, there's a link in the cell that was clicked, but I suggest checking the MDN and MSDN (for the window.event object)

How to create a sleep/delay in nodejs that is Blocking?

blocking the main thread is not a good style for node because in most cases more then one person is using it. You should use settimeout/setinterval in combination with callbacks.

Android read text raw resource file

Well with Kotlin u can do it just in one line of code:

resources.openRawResource(R.raw.rawtextsample).bufferedReader().use { it.readText() }

Or even declare extension function:

fun Resources.getRawTextFile(@RawRes id: Int) =
        openRawResource(id).bufferedReader().use { it.readText() }

And then just use it straightaway:

val txtFile = resources.getRawTextFile(R.raw.rawtextsample)

How to store custom objects in NSUserDefaults

Synchronize the data/object that you have saved into NSUserDefaults

-(void)saveCustomObject:(Player *)object
{ 
    NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
    NSData *myEncodedObject = [NSKeyedArchiver archivedDataWithRootObject:object];
    [prefs setObject:myEncodedObject forKey:@"testing"];
    [prefs synchronize];
}

Hope this will help you. Thanks

Error: Cannot find module '../lib/utils/unsupported.js' while using Ionic

This may happen when the npm/lib folder got emptied for some reason (could also happen due to permission issues in the last usage).

A reinstallation of the node could solve the issue (as stated on other answers here), but I would suggest using a wonderful tool called nvm (Node Version Manager), which is able to manage multiple version of node and npm - this is mostly useful on dev machines with more than one projects require different versions of node.

When you install nvm, this message will go away and you will have the latest version of node and npm to use.

In order to see the list of currently installed node versions in your nvm, just run:

nvm list

In order to install and use a new node version, run:

nvm install <node_version>

For example to install latest version of node 10.x, run:

nvm install 10

In order to switch to currently installed version, run:

nvm use <node_version>

In order to switch to system's original node version, just run:

nvm use system

Hope this helps.

Good luck!

PHP convert string to hex and hex to string

Using @bill-shirley answer with a little addition

function str_to_hex($string) {
$hexstr = unpack('H*', $string);
return array_shift($hexstr);
}
function hex_to_str($string) {
return hex2bin("$string");
}

Usage:

  $str = "Go placidly amidst the noise";
  $hexstr = str_to_hex($str);// 476f20706c616369646c7920616d6964737420746865206e6f697365
  $strstr = hex_to_str($str);// Go placidly amidst the noise

Check if certain value is contained in a dataframe column in pandas

You can use any:

print any(df.column == 07311954)
True       #true if it contains the number, false otherwise

If you rather want to see how many times '07311954' occurs in a column you can use:

df.column[df.column == 07311954].count()

Find text string using jQuery?

If you just want the node closest to the text you're searching for, you could use this:

$('*:contains("my text"):last');

This will even work if your HTML looks like this:

<p> blah blah <strong>my <em>text</em></strong></p>

Using the above selector will find the <strong> tag, since that's the last tag which contains that entire string.

Error: 0xC0202009 at Data Flow Task, OLE DB Destination [43]: SSIS Error Code DTS_E_OLEDBERROR. An OLE DB error has occurred. Error code: 0x80040E21

So this error is occurring because you have a value in your source for the AppID column that is not valid for your AppID column in the destination.

Some possible examples:

  • You're trying to insert a 10 character value into an 8 character field.
  • You're trying to insert a value larger than 127 into a tinyint field.
  • You're trying to insert the value 6.4578 into a decimal(5,1) field.

SSIS is governed by metadata, and it expects that you've set up your inputs and outputs properly such that the acceptable values for both are within the same range.

Best practices for catching and re-throwing .NET exceptions

FYI I just tested this and the stack trace reported by 'throw;' is not an entirely correct stack trace. Example:

    private void foo()
    {
        try
        {
            bar(3);
            bar(2);
            bar(1);
            bar(0);
        }
        catch(DivideByZeroException)
        {
            //log message and rethrow...
            throw;
        }
    }

    private void bar(int b)
    {
        int a = 1;
        int c = a/b;  // Generate divide by zero exception.
    }

The stack trace points to the origin of the exception correctly (reported line number) but the line number reported for foo() is the line of the throw; statement, hence you cannot tell which of the calls to bar() caused the exception.

Encode/Decode URLs in C++

You can use "g_uri_escape_string()" function provided glib.h. https://developer.gnome.org/glib/stable/glib-URI-Functions.html

#include <stdio.h>
#include <stdlib.h>
#include <glib.h>
int main() {
    char *uri = "http://www.example.com?hello world";
    char *encoded_uri = NULL;
    //as per wiki (https://en.wikipedia.org/wiki/Percent-encoding)
    char *escape_char_str = "!*'();:@&=+$,/?#[]"; 
    encoded_uri = g_uri_escape_string(uri, escape_char_str, TRUE);
    printf("[%s]\n", encoded_uri);
    free(encoded_uri);

    return 0;
}

compile it with:

gcc encoding_URI.c `pkg-config --cflags --libs glib-2.0`

Query to check index on a table

Simply you can find index name and column names of a particular table using below command

SP_HELPINDEX 'tablename'

It work's for me

Uncaught ReferenceError: <function> is not defined at HTMLButtonElement.onclick

Same Problem I had... I was writing all the script in a seperate file and was adding it through tag into the end of the HTML file after body tag. After moving the the tag inside the body tag it works fine. before :

</body>
<script>require('../script/viewLog.js')</script>

after :

<script>require('../script/viewLog.js')</script>
</body>

Catch paste input

This proved to be quite illusive. The value of the input is not updated prior to the execution of the code inside the paste event function. I tried calling other events from within the paste event function but the input value is still not updated with the pasted text inside the function of any events. That is all events apart from keyup. If you call keyup from within the paste event function you can sanitize the pasted text from within the keyup event function. like so...

$(':input').live
(
    'input paste',
    function(e)
    {
        $(this).keyup();
    }
);

$(':input').live
(
    'keyup',
    function(e)
    {
        // sanitize pasted text here
    }
);

There is one caveat here. In Firefox, if you reset the input text on every keyup, if the text is longer than the viewable area allowed by the input width, then resetting the value on every keyup breaks the browser functionality that auto scrolls the text to the caret position at the end of the text. Instead the text scrolls back to the beginning leaving the caret out of view.

How to add display:inline-block in a jQuery show() function?

<style>
.demo-ele{display:inline-block}
</style>

<div class="demo-ele" style="display:none">...</div>

<script>
$(".demo-ele").show(1000);//hide first, show with inline-block
<script>

Completely remove MariaDB or MySQL from CentOS 7 or RHEL 7

These steps are working on CentOS 6.5 so they should work on CentOS 7 too:

(EDIT - exactly the same steps work for MariaDB 10.3 on CentOS 8)

  1. yum remove mariadb mariadb-server
  2. rm -rf /var/lib/mysql If your datadir in /etc/my.cnf points to a different directory, remove that directory instead of /var/lib/mysql
  3. rm /etc/my.cnf the file might have already been deleted at step 1
  4. Optional step: rm ~/.my.cnf
  5. yum install mariadb mariadb-server

[EDIT] - Update for MariaDB 10.1 on CentOS 7

The steps above worked for CentOS 6.5 and MariaDB 10.

I've just installed MariaDB 10.1 on CentOS 7 and some of the steps are slightly different.

Step 1 would become:

yum remove MariaDB-server MariaDB-client

Step 5 would become:

yum install MariaDB-server MariaDB-client

The other steps remain the same.

LDAP server which is my base dn

Either you set LDAP_DOMAIN variable or you misconfigured it. Jump inside of ldap machine/container and run:

slapcat > backup.ldif

If it fails, check punctuation, quotes etc while you assigned variable "LDAP_DOMAIN" Otherwise you will find answer inside on backup.ldif file.

Python Remove last char from string and return it

Yes, python strings are immutable and any modification will result in creating a new string. This is how it's mostly done.

So, go ahead with it.

How to fix 'Notice: Undefined index:' in PHP form action

Change $_POST to $_FILES and make sure your enctype is "multipart/form-data"

Is your input field actually in a form?

<form method="POST" action="update.php">
    <input type="hidden" name="filename" value="test" />
</form>

Checking from shell script if a directory contains files

# Works on hidden files, directories and regular files
### isEmpty()
# This function takes one parameter:
# $1 is the directory to check
# Echoes "huzzah" if the directory has files
function isEmpty(){
  if [ "$(ls -A $1)" ]; then
    echo "huzzah"
  else 
    echo "has no files"
  fi
}

How can I make my string property nullable?

String is a reference type and always nullable, you don't need to do anything special. Specifying that a type is nullable is necessary only for value types.

Setting Django up to use MySQL

MySQL support is simple to add. In your DATABASES dictionary, you will have an entry like this:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql', 
        'NAME': 'DB_NAME',
        'USER': 'DB_USER',
        'PASSWORD': 'DB_PASSWORD',
        'HOST': 'localhost',   # Or an IP Address that your DB is hosted on
        'PORT': '3306',
    }
}

You also have the option of utilizing MySQL option files, as of Django 1.7. You can accomplish this by setting your DATABASES array like so:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'OPTIONS': {
            'read_default_file': '/path/to/my.cnf',
        },
    }
}

You also need to create the /path/to/my.cnf file with similar settings from above

[client]
database = DB_NAME
host = localhost
user = DB_USER
password = DB_PASSWORD
default-character-set = utf8

With this new method of connecting in Django 1.7, it is important to know the order connections are established:

1. OPTIONS.
2. NAME, USER, PASSWORD, HOST, PORT
3. MySQL option files.

In other words, if you set the name of the database in OPTIONS, this will take precedence over NAME, which would override anything in a MySQL option file.


If you are just testing your application on your local machine, you can use

python manage.py runserver

Adding the ip:port argument allows machines other than your own to access your development application. Once you are ready to deploy your application, I recommend taking a look at the chapter on Deploying Django on the djangobook

Mysql default character set is often not utf-8, therefore make sure to create your database using this sql:

CREATE DATABASE mydatabase CHARACTER SET utf8 COLLATE utf8_bin

If you are using Oracle's MySQL connector your ENGINE line should look like this:

'ENGINE': 'mysql.connector.django',

Note that you will first need to install mysql on your OS.

brew install mysql (MacOS)

Also, the mysql client package has changed for python 3 (MySQL-Client works only for python 2)

pip3 install mysqlclient

Set variable with multiple values and use IN

Use a Temp Table or a Table variable, e.g.

select 'A' as [value]
into #tmp
union
select 'B'
union 
select 'C'

and then

SELECT   
blah 
FROM    foo 
WHERE   myField IN (select [value] from #tmp) 

or

SELECT   
f.blah 
FROM foo f INNER JOIN #tmp t ON f.myField = t.[value]

Android Log.v(), Log.d(), Log.i(), Log.w(), Log.e() - When to use each one?

The different methods are indications of priority. As you've listed them, they're going from least to most important. I think how you specifically map them to debug logs in your code depends on the component or app you're working on, as well as how Android treats them on different build flavors (eng, userdebug, and user). I have done a fair amount of work in the native daemons in Android, and this is how I do it. It may not apply directly to your app, but there may be some common ground. If my explanation sounds vague, it's because some of this is more of an art than a science. My basic rule is to be as efficient as possible, ensure you can reasonably debug your component without killing the performance of the system, and always check for errors and log them.

V - Printouts of state at different intervals, or upon any events occurring which my component processes. Also possibly very detailed printouts of the payloads of messages/events that my component receives or sends.

D - Details of minor events that occur within my component, as well as payloads of messages/events that my component receives or sends.

I - The header of any messages/events that my component receives or sends, as well as any important pieces of the payload which are critical to my component's operation.

W - Anything that happens that is unusual or suspicious, but not necessarily an error.

E - Errors, meaning things that aren't supposed to happen when things are working as they should.

The biggest mistake I see people make is that they overuse things like V, D, and I, but never use W or E. If an error is, by definition, not supposed to happen, or should only happen very rarely, then it's extremely cheap for you to log a message when it occurs. On the other hand, if every time somebody presses a key you do a Log.i(), you're abusing the shared logging resource. Of course, use common sense and be careful with error logs for things outside of your control (like network errors), or those contained in tight loops.

Maybe Bad

Log.i("I am here");

Good

Log.e("I shouldn't be here");

With all this in mind, the closer your code gets to "production ready", the more you can restrict the base logging level for your code (you need V in alpha, D in beta, I in production, or possibly even W in production). You should run through some simple use cases and view the logs to ensure that you can still mostly understand what's happening as you apply more restrictive filtering. If you run with the filter below, you should still be able to tell what your app is doing, but maybe not get all the details.

logcat -v threadtime MyApp:I *:S

How to remove old Docker containers

To remove ALL stopped docker containers, run:-

$ docker container prune

You'll have to be careful with this command since it removes all stopped containers indiscriminately so make sure there's no stopped/currently unused container that you may still have use of.

A more precise alternative is to remove the container by ID. You'll have to first list the stopped containers using this command:-

docker ps --filter "status=exited"

You'll then copy the ID of the container you want to remove. Thereafter, execute the following command that removes a single container,

docker container rm <container ID>

or the one below to remove multiple containers at once by running:-

docker container rm <container ID 1> <container ID 2> <container ID n>

How to initialize struct?

Structure types should, whenever practical, either have all of their state encapsulated in public fields which may independently be set to any values which are valid for their respective type, or else behave as a single unified value which can only bet set via constructor, factory, method, or else by passing an instance of the struct as an explicit ref parameter to one of its public methods. Contrary to what some people claim, that there's nothing wrong with a struct having public fields, if it is supposed to represent a set of values which may sensibly be either manipulated individually or passed around as a group (e.g. the coordinates of a point). Historically, there have been problems with structures that had public property setters, and a desire to avoid public fields (implying that setters should be used instead) has led some people to suggest that mutable structures should be avoided altogether, but fields do not have the problems that properties had. Indeed, an exposed-field struct is the ideal representation for a loose collection of independent variables, since it is just a loose collection of variables.

In your particular example, however, it appears that the two fields of your struct are probably not supposed to be independent. There are three ways your struct could sensibly be designed:

  • You could have the only public field be the string, and then have a read-only "helper" property called length which would report its length if the string is non-null, or return zero if the string is null.

  • You could have the struct not expose any public fields, property setters, or mutating methods, and have the contents of the only field--a private string--be specified in the object's constructor. As above, length would be a property that would report the length of the stored string.

  • You could have the struct not expose any public fields, property setters, or mutating methods, and have two private fields: one for the string and one for the length, both of which would be set in a constructor that takes a string, stores it, measures its length, and stores that. Determining the length of a string is sufficiently fast that it probably wouldn't be worthwhile to compute and cache it, but it might be useful to have a structure that combined a string and its GetHashCode value.

It's important to be aware of a detail with regard to the third design, however: if non-threadsafe code causes one instance of the structure to be read while another thread is writing to it, that may cause the accidental creation of a struct instance whose field values are inconsistent. The resulting behaviors may be a little different from those that occur when classes are used in non-threadsafe fashion. Any code having anything to do with security must be careful not to assume that structure fields will be in a consistent state, since malicious code--even in a "full trust" enviroment--can easily generate structs whose state is inconsistent if that's what it wants to do.

PS -- If you wish to allow your structure to be initialized using an assignment from a string, I would suggest using an implicit conversion operator and making Length be a read-only property that returns the length of the underlying string if non-null, or zero if the string is null.

Query Mongodb on month, day, year... of a datetime

Use the $expr operator which allows the use of aggregation expressions within the query language. This will give you the power to use the Date Aggregation Operators in your query as follows:

month = 11
db.mydatabase.mycollection.find({ 
    "$expr": { 
        "$eq": [ { "$month": "$date" }, month ] 
    } 
})

or

day = 17
db.mydatabase.mycollection.find({ 
    "$expr": { 
        "$eq": [ { "$dayOfMonth": "$date" }, day ] 
    } 
})

You could also run an aggregate operation with the aggregate() function that takes in a $redact pipeline:

month = 11
db.mydatabase.mycollection.aggregate([
    {
        "$redact": {
            "$cond": [
                { "$eq": [ { "$month": "$date" }, month ] },
                "$$KEEP",
                "$$PRUNE"
            ]
        }
    }
])

For the other request

day = 17
db.mydatabase.mycollection.aggregate([
    {
        "$redact": {
            "$cond": [
                { "$eq": [ { "$dayOfMonth": "$date" }, day ] },
                "$$KEEP",
                "$$PRUNE"
            ]
        }
    }
])

Using OR

month = 11
day = 17
db.mydatabase.mycollection.aggregate([
    {
        "$redact": {
            "$cond": [
                { 
                    "$or": [ 
                        { "$eq": [ { "$month": "$date" }, month ] },
                        { "$eq": [ { "$dayOfMonth": "$date" }, day ] }
                    ] 
                },
                "$$KEEP",
                "$$PRUNE"
            ]
        }
    }
])

Using AND

var month = 11,
    day = 17;
db.collection.aggregate([
    {
        "$redact": {
            "$cond": [
                { 
                    "$and": [ 
                        { "$eq": [ { "$month": "$createdAt" }, month ] },
                        { "$eq": [ { "$dayOfMonth": "$createdAt" }, day ] }
                    ] 
                },
                "$$KEEP",
                "$$PRUNE"
            ]
        }
    }
])

The $redact operator incorporates the functionality of $project and $match pipeline and will return all documents match the condition using $$KEEP and discard from the pipeline those that don't match using the $$PRUNE variable.

MySQL - sum column value(s) based on row from the same table

I think you're making this a bit more complicated than it needs to be.

SELECT
    ProductID,
    SUM(IF(PaymentMethod = 'Cash', Amount, 0)) AS 'Cash',
    -- snip
    SUM(Amount) AS Total
FROM
    Payments
WHERE
    SaleDate = '2012-02-10'
GROUP BY
    ProductID

How to pass multiple arguments in processStartInfo?

startInfo.Arguments = "/c \"netsh http add sslcert ipport=127.0.0.1:8085 certhash=0000000000003ed9cd0c315bbb6dc1c08da5e6 appid={00112233-4455-6677-8899-AABBCCDDEEFF} clientcertnegotiation=enable\"";

and...

startInfo.Arguments = "/c \"makecert -sk server -sky exchange -pe -n CN=localhost -ir LocalMachine -is Root -ic MyCA.cer -sr LocalMachine -ss My MyAdHocTestCert.cer\"";

The /c tells cmd to quit once the command has completed. Everything after /c is the command you want to run (within cmd), including all of the arguments.

What is the reason for having '//' in Python?

// is unconditionally "flooring division", e.g:

>>> 4.0//1.5
2.0

As you see, even though both operands are floats, // still floors -- so you always know securely what it's going to do.

Single / may or may not floor depending on Python release, future imports, and even flags on which Python's run, e.g.:

$ python2.6 -Qold -c 'print 2/3'
0
$ python2.6 -Qnew -c 'print 2/3'
0.666666666667

As you see, single / may floor, or it may return a float, based on completely non-local issues, up to and including the value of the -Q flag...;-).

So, if and when you know you want flooring, always use //, which guarantees it. If and when you know you don't want flooring, slap a float() around other operand and use /. Any other combination, and you're at the mercy of version, imports, and flags!-)

How can I check for "undefined" in JavaScript?

You can use typeof, like this:

if (typeof something != "undefined") {
    // ...
}

How to make parent wait for all child processes to finish?

POSIX defines a function: wait(NULL);. It's the shorthand for waitpid(-1, NULL, 0);, which will suspends the execution of the calling process until any one child process exits. Here, 1st argument of waitpid indicates wait for any child process to end.

In your case, have the parent call it from within your else branch.

Rails: Using greater than/less than with a where statement

I've only tested this in Rails 4 but there's an interesting way to use a range with a where hash to get this behavior.

User.where(id: 201..Float::INFINITY)

will generate the SQL

SELECT `users`.* FROM `users`  WHERE (`users`.`id` >= 201)

The same can be done for less than with -Float::INFINITY.

I just posted a similar question asking about doing this with dates here on SO.

>= vs >

To avoid people having to dig through and follow the comments conversation here are the highlights.

The method above only generates a >= query and not a >. There are many ways to handle this alternative.

For discrete numbers

You can use a number_you_want + 1 strategy like above where I'm interested in Users with id > 200 but actually look for id >= 201. This is fine for integers and numbers where you can increment by a single unit of interest.

If you have the number extracted into a well named constant this may be the easiest to read and understand at a glance.

Inverted logic

We can use the fact that x > y == !(x <= y) and use the where not chain.

User.where.not(id: -Float::INFINITY..200)

which generates the SQL

SELECT `users`.* FROM `users` WHERE (NOT (`users`.`id` <= 200))

This takes an extra second to read and reason about but will work for non discrete values or columns where you can't use the + 1 strategy.

Arel table

If you want to get fancy you can make use of the Arel::Table.

User.where(User.arel_table[:id].gt(200))

will generate the SQL

"SELECT `users`.* FROM `users` WHERE (`users`.`id` > 200)"

The specifics are as follows:

User.arel_table              #=> an Arel::Table instance for the User model / users table
User.arel_table[:id]         #=> an Arel::Attributes::Attribute for the id column
User.arel_table[:id].gt(200) #=> an Arel::Nodes::GreaterThan which can be passed to `where`

This approach will get you the exact SQL you're interested in however not many people use the Arel table directly and can find it messy and/or confusing. You and your team will know what's best for you.

Bonus

Starting in Rails 5 you can also do this with dates!

User.where(created_at: 3.days.ago..DateTime::Infinity.new)

will generate the SQL

SELECT `users`.* FROM `users` WHERE (`users`.`created_at` >= '2018-07-07 17:00:51')

Double Bonus

Once Ruby 2.6 is released (December 25, 2018) you'll be able to use the new infinite range syntax! Instead of 201..Float::INFINITY you'll be able to just write 201... More info in this blog post.

Simple DateTime sql query

SELECT * 
  FROM TABLENAME 
 WHERE [DateTime] >= '2011-04-12 12:00:00 AM'
   AND [DateTime] <= '2011-05-25 3:35:04 AM'

If this doesn't work, please script out your table and post it here. this will help us get you the correct answer quickly.

How to delete stuff printed to console by System.out.println()?

I have successfully used the following:

@Before
public void dontPrintExceptions() {
    // get rid of the stack trace prints for expected exceptions
    System.setErr(new PrintStream(new NullStream()));
}

NullStream lives in the import com.sun.tools.internal.xjc.util package so might not be available on all Java implementations, but it's just an OutputStream, should be simple enough to write your own.

SHA-1 fingerprint of keystore certificate

If you are using eclipse, go to: Window->Preferences->Android->Build You will find what you are looking there.

enter image description here

PHP How to find the time elapsed since a date time?

Here I am using custom function for finding the time elapsed since a date time.


echo Datetodays('2013-7-26 17:01:10');

function Datetodays($d) {

        $date_start = $d;
        $date_end = date('Y-m-d H:i:s');

        define('SECOND', 1);
        define('MINUTE', SECOND * 60);
        define('HOUR', MINUTE * 60);
        define('DAY', HOUR * 24);
        define('WEEK', DAY * 7);

        $t1 = strtotime($date_start);
        $t2 = strtotime($date_end);
        if ($t1 > $t2) {
            $diffrence = $t1 - $t2;
        } else {
            $diffrence = $t2 - $t1;
        }

        //echo "
".$date_end." ".$date_start." ".$diffrence; $results['major'] = array(); // whole number representing larger number in date time relationship $results1 = array(); $string = ''; $results['major']['weeks'] = floor($diffrence / WEEK); $results['major']['days'] = floor($diffrence / DAY); $results['major']['hours'] = floor($diffrence / HOUR); $results['major']['minutes'] = floor($diffrence / MINUTE); $results['major']['seconds'] = floor($diffrence / SECOND); //print_r($results); // Logic: // Step 1: Take the major result and transform it into raw seconds (it will be less the number of seconds of the difference) // ex: $result = ($results['major']['weeks']*WEEK) // Step 2: Subtract smaller number (the result) from the difference (total time) // ex: $minor_result = $difference - $result // Step 3: Take the resulting time in seconds and convert it to the minor format // ex: floor($minor_result/DAY) $results1['weeks'] = floor($diffrence / WEEK); $results1['days'] = floor((($diffrence - ($results['major']['weeks'] * WEEK)) / DAY)); $results1['hours'] = floor((($diffrence - ($results['major']['days'] * DAY)) / HOUR)); $results1['minutes'] = floor((($diffrence - ($results['major']['hours'] * HOUR)) / MINUTE)); $results1['seconds'] = floor((($diffrence - ($results['major']['minutes'] * MINUTE)) / SECOND)); //print_r($results1); if ($results1['weeks'] != 0 && $results1['days'] == 0) { if ($results1['weeks'] == 1) { $string = $results1['weeks'] . ' week ago'; } else { if ($results1['weeks'] == 2) { $string = $results1['weeks'] . ' weeks ago'; } else { $string = '2 weeks ago'; } } } elseif ($results1['weeks'] != 0 && $results1['days'] != 0) { if ($results1['weeks'] == 1) { $string = $results1['weeks'] . ' week ago'; } else { if ($results1['weeks'] == 2) { $string = $results1['weeks'] . ' weeks ago'; } else { $string = '2 weeks ago'; } } } elseif ($results1['weeks'] == 0 && $results1['days'] != 0) { if ($results1['days'] == 1) { $string = $results1['days'] . ' day ago'; } else { $string = $results1['days'] . ' days ago'; } } elseif ($results1['days'] != 0 && $results1['hours'] != 0) { $string = $results1['days'] . ' day and ' . $results1['hours'] . ' hours ago'; } elseif ($results1['days'] == 0 && $results1['hours'] != 0) { if ($results1['hours'] == 1) { $string = $results1['hours'] . ' hour ago'; } else { $string = $results1['hours'] . ' hours ago'; } } elseif ($results1['hours'] != 0 && $results1['minutes'] != 0) { $string = $results1['hours'] . ' hour and ' . $results1['minutes'] . ' minutes ago'; } elseif ($results1['hours'] == 0 && $results1['minutes'] != 0) { if ($results1['minutes'] == 1) { $string = $results1['minutes'] . ' minute ago'; } else { $string = $results1['minutes'] . ' minutes ago'; } } elseif ($results1['minutes'] != 0 && $results1['seconds'] != 0) { $string = $results1['minutes'] . ' minute and ' . $results1['seconds'] . ' seconds ago'; } elseif ($results1['minutes'] == 0 && $results1['seconds'] != 0) { if ($results1['seconds'] == 1) { $string = $results1['seconds'] . ' second ago'; } else { $string = $results1['seconds'] . ' seconds ago'; } } return $string; } ?>

How do I convert a date/time to epoch time (unix time/seconds since 1970) in Perl?

This is the simplest way to get unix time:

use Time::Local;
timelocal($second,$minute,$hour,$day,$month-1,$year);

Note the reverse order of the arguments and that January is month 0. For many more options, see the DateTime module from CPAN.

As for parsing, see the Date::Parse module from CPAN. If you really need to get fancy with date parsing, the Date::Manip may be helpful, though its own documentation warns you away from it since it carries a lot of baggage (it knows things like common business holidays, for example) and other solutions are much faster.

If you happen to know something about the format of the date/times you'll be parsing then a simple regular expression may suffice but you're probably better off using an appropriate CPAN module. For example, if you know the dates will always be in YMDHMS order, use the CPAN module DateTime::Format::ISO8601.


For my own reference, if nothing else, below is a function I use for an application where I know the dates will always be in YMDHMS order with all or part of the "HMS" part optional. It accepts any delimiters (eg, "2009-02-15" or "2009.02.15"). It returns the corresponding unix time (seconds since 1970-01-01 00:00:00 GMT) or -1 if it couldn't parse it (which means you better be sure you'll never legitimately need to parse the date 1969-12-31 23:59:59). It also presumes two-digit years XX up to "69" refer to "20XX", otherwise "19XX" (eg, "50-02-15" means 2050-02-15 but "75-02-15" means 1975-02-15).

use Time::Local;

sub parsedate { 
  my($s) = @_;
  my($year, $month, $day, $hour, $minute, $second);

  if($s =~ m{^\s*(\d{1,4})\W*0*(\d{1,2})\W*0*(\d{1,2})\W*0*
                 (\d{0,2})\W*0*(\d{0,2})\W*0*(\d{0,2})}x) {
    $year = $1;  $month = $2;   $day = $3;
    $hour = $4;  $minute = $5;  $second = $6;
    $hour |= 0;  $minute |= 0;  $second |= 0;  # defaults.
    $year = ($year<100 ? ($year<70 ? 2000+$year : 1900+$year) : $year);
    return timelocal($second,$minute,$hour,$day,$month-1,$year);  
  }
  return -1;
}

VBA Convert String to Date

Looks like it could be throwing the error on the empty data row, have you tried to just make sure itemDate isn't empty before you run the CDate() function? I think this might be your problem.

How to update attributes without validation

You can do something like:

object.attribute = value
object.save(:validate => false)

Android Use Done button on Keyboard to click button

You can use this one also (sets a special listener to be called when an action is performed on the EditText), it works both for DONE and RETURN:

max.setOnEditorActionListener(new OnEditorActionListener() {
        @Override
        public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
            if ((event != null && (event.getKeyCode() == KeyEvent.KEYCODE_ENTER)) || (actionId == EditorInfo.IME_ACTION_DONE)) {
                Log.i(TAG,"Enter pressed");
            }    
            return false;
        }
    });

MySQL ERROR 1045 (28000): Access denied for user 'bill'@'localhost' (using password: YES)

A related problem in my case was trying to connect using :

mysql -u mike -p mypass

Whitespace IS apparently allowed between the -u #uname# but NOT between the -p and #password#

Therefore needed:

mysql -u mike -pmypass

Otherwise with white-space between -p mypass mysql takes 'mypass' as the db name

How to add System.Windows.Interactivity to project?

Alternative solution is to modify your current Visual Studio installation in the Visual Studio Installer

Win+R %ProgramFiles(x86)%\Microsoft Visual Studio\Installer\vs_installer.exe

adding the Blend for Visual Studio SDK for .NET 'Individual component' under 'SDKs, libraries, and frameworks':

enter image description here after adding this component System.Windows.Interactivity should appear in its regular location Add Reference/Assemblies/Extensions.


It appears this would only work for VS2017 or earlier. For later versions, please refer to other answers.

How to add custom validation to an AngularJS form?

I extended @Ben Lesh's answer with an ability to specify whether the validation is case sensitive or not (default)

use:

<input type="text" name="fruitName" ng-model="data.fruitName" blacklist="Coconuts,Bananas,Pears" caseSensitive="true" required/>

code:

angular.module('crm.directives', []).
directive('blacklist', [
    function () {
        return {
            restrict: 'A',
            require: 'ngModel',
            scope: {
                'blacklist': '=',
            },
            link: function ($scope, $elem, $attrs, modelCtrl) {

                var check = function (value) {
                    if (!$attrs.casesensitive) {
                        value = (value && value.toUpperCase) ? value.toUpperCase() : value;

                        $scope.blacklist = _.map($scope.blacklist, function (item) {
                            return (item.toUpperCase) ? item.toUpperCase() : item
                        })
                    }

                    return !_.isArray($scope.blacklist) || $scope.blacklist.indexOf(value) === -1;
                }

                //For DOM -> model validation
                modelCtrl.$parsers.unshift(function (value) {
                    var valid = check(value);
                    modelCtrl.$setValidity('blacklist', valid);

                    return value;
                });
                //For model -> DOM validation
                modelCtrl.$formatters.unshift(function (value) {
                    modelCtrl.$setValidity('blacklist', check(value));
                    return value;
                });
            }
        };
    }
]);

How do I remove the file suffix and path portion from a path string in Bash?

The basename does that, removes the path. It will also remove the suffix if given and if it matches the suffix of the file but you would need to know the suffix to give to the command. Otherwise you can use mv and figure out what the new name should be some other way.

Javascript - Track mouse position

If just want to track the mouse movement visually:

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
<title></title>_x000D_
</head>_x000D_
<style type="text/css">_x000D_
* { margin: 0; padding: 0; }_x000D_
html, body { width: 100%; height: 100%; overflow: hidden; }_x000D_
</style>_x000D_
<body>_x000D_
<canvas></canvas>_x000D_
_x000D_
<script type="text/javascript">_x000D_
var_x000D_
canvas    = document.querySelector('canvas'),_x000D_
ctx       = canvas.getContext('2d'),_x000D_
beginPath = false;_x000D_
_x000D_
canvas.width  = window.innerWidth;_x000D_
canvas.height = window.innerHeight;_x000D_
_x000D_
document.body.addEventListener('mousemove', function (event) {_x000D_
 var x = event.clientX, y = event.clientY;_x000D_
_x000D_
 if (beginPath) {_x000D_
  ctx.lineTo(x, y);_x000D_
  ctx.stroke();_x000D_
 } else {_x000D_
  ctx.beginPath();_x000D_
  ctx.moveTo(x, y);_x000D_
  beginPath = true;_x000D_
 }_x000D_
}, false);_x000D_
</script>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

"Cross origin requests are only supported for HTTP." error when loading a local file

Easy solution for whom using VS Code

I've been getting this error for a while. Most of the answers works. But I found a different solution. If you don't want to deal with node.js or any other solution in here and you are working with an HTML file (calling functions from another js file or fetch json api's) try to use Live Server extension.

It allows you to open a live server easily. And because of it creates localhost server, the problem is resolving. You can simply start the localhost by open a HTML file and right-click on the editor and click on Open with Live Server.

It basically load the files using http://localhost/index.html instead of using file://....

EDIT

It is not necessary to have a .html file. You can start the Live Server with shortcuts.

Hit (alt+L, alt+O) to Open the Server and (alt+L, alt+C) to Stop the server. [On MAC, cmd+L, cmd+O and cmd+L, cmd+C]

Hope it will help someone :)

PostgreSQL psql terminal command

psql --pset=format=FORMAT

Great for executing queries from command line, e.g.

psql --pset=format=unaligned -c "select bandanavalue from bandana where bandanakey = 'atlassian.confluence.settings';"

Internal and external fragmentation

First of all the term fragmentation cues there's an entity divided into parts — fragments.

  • Internal fragmentation: Typical paper book is a collection of pages (text divided into pages). When a chapter's end isn't located at the end of page and new chapter starts from new page, there's a gap between those chapters and it's a waste of space — a chunk (page for a book) has unused space inside (internally) — "white space"

  • External fragmentation: Say you have a paper diary and you didn't write your thoughts sequentially page after page, but, rather randomly. You might end up with a situation when you'd want to write 3 pages in row, but you can't since there're no 3 clean pages one-by-one, you might have 15 clean pages in the diary totally, but they're not contiguous

ObjectiveC Parse Integer from String

You can just convert the string like that [str intValue] or [str integerValue]

integerValue Returns the NSInteger value of the receiver’s text.

  • (NSInteger)integerValue Return Value The NSInteger value of the receiver’s text, assuming a decimal representation and skipping whitespace at the beginning of the string. Returns 0 if the receiver doesn’t begin with a valid decimal text representation of a number.

for more information refer here

GitHub - List commits by author

Just add ?author=<emailaddress> or ?author=<githubUserName> to the url when viewing the "commits" section of a repo.

Catching FULL exception message

You can add:

-ErrorVariable errvar

And then look in $errvar.

Center an element in Bootstrap 4 Navbar

use mx-auto will do the job

<ul class="navbar-nav mx-auto">

JQuery html() vs. innerHTML

To answer your question:

.html() will just call .innerHTML after doing some checks for nodeTypes and stuff. It also uses a try/catch block where it tries to use innerHTML first and if that fails, it'll fallback gracefully to jQuery's .empty() + append()

What command means "do nothing" in a conditional in Bash?

You can probably just use the true command:

if [ "$a" -ge 10 ]; then
    true
elif [ "$a" -le 5 ]; then
    echo "1"
else
    echo "2"
fi

An alternative, in your example case (but not necessarily everywhere) is to re-order your if/else:

if [ "$a" -le 5 ]; then
    echo "1"
elif [ "$a" -lt 10 ]; then
    echo "2"
fi

JavaScript equivalent of PHP’s die

You can only break a block scope if you label it. For example:

myBlock: {
  var a = 0;
  break myBlock;
  a = 1; // this is never run
};
a === 0;

You cannot break a block scope from within a function in the scope. This means you can't do stuff like:

foo: { // this doesn't work
  (function() {
    break foo;
  }());
}

You can do something similar though with functions:

function myFunction() {myFunction:{
  // you can now use break myFunction; instead of return;
}}

cannot load such file -- bundler/setup (LoadError)

You can try to run:

bundle exec rake rails:update:bin

As @Dinesh mentioned in Rails 5:

rails app:update:bin

How to escape double quotes in JSON

if you want to escape double quote in JSON use \\ to escape it.

example if you want to create json of following javascript object

{time: '7 "o" clock'}

then you must write in following way

'{"time":"7 \\"o\\" clock"}'

if we parse it using JSON.parse()

JSON.parse('{"time":"7 \\"o\\" clock"}')

result will be

{time: "7 "o" clock"}

error while loading shared libraries: libncurses.so.5:

If libncurses is not installed then install it and try again. sudo apt-get install libncurses5:i386

or sudo apt-get install libncurses5 for 64 bit binaries

Also install the collection of libraries by using this command sudo apt-get install ia32-libs

Jquery: how to sleep or delay?

If you can't use the delay method as Robert Harvey suggested, you can use setTimeout.

Eg.

setTimeout(function() {$("#test").animate({"top":"-=80px"})} , 1500); // delays 1.5 sec
setTimeout(function() {$("#test").animate({"opacity":"0"})} , 1500 + 1000); // delays 1 sec after the previous one

Android button with different background colors

You have to put the selector.xml file in the drwable folder. Then write: android:background="@drawable/selector". This takes care of the pressed and focussed states.

Enable remote connections for SQL Server Express 2012

You can also set

Listen All to NO

in the protocol dialog then in the IP address IP1 (say)

set enabled to Yes,

define yr IP address,

set TCP Dynamic to Blank and

TCP port to 1433 (or whatever)

Is there a Public FTP server to test upload and download?

There's lots of FTP sites you can get into with the 'anonymous' account and download, but a 'public' site that allows anonymous uploads would be utterly swamped with pr0n and warez in short order.

It's easy enough to set up your own FTP server for testing uploads. There's plenty of them for most any desktop OS. There's one built into IIS, for instance.

Calling a JavaScript function named in a variable

I'd avoid eval.

To solve this problem, you should know these things about JavaScript.

  1. Functions are first-class objects, so they can be properties of an object (in which case they are called methods) or even elements of arrays.
  2. If you aren't choosing the object a function belongs to, it belongs to the global scope. In the browser, that means you're hanging it on the object named "window," which is where globals live.
  3. Arrays and objects are intimately related. (Rumor is they might even be the result of incest!) You can often substitute using a dot . rather than square brackets [], or vice versa.

Your problem is a result of considering the dot manner of reference rather than the square bracket manner.

So, why not something like,

window["functionName"]();

That's assuming your function lives in the global space. If you've namespaced, then:

myNameSpace["functionName"]();

Avoid eval, and avoid passing a string in to setTimeout and setInterval. I write a lot of JS, and I NEVER need eval. "Needing" eval comes from not knowing the language deeply enough. You need to learn about scoping, context, and syntax. If you're ever stuck with an eval, just ask--you'll learn quickly.

How to run server written in js with Node.js

I open a text editor, in my case I used Atom. Paste this code

var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');

and save as

helloworld.js

in

c:\xampp\htdocs\myproject 

directory. Next I open node.js commamd prompt enter

cd c:\xampp\htdocs\myproject

next

node helloworld.js

next I open my chrome browser and I type

http://localhost:1337

and there it is.

How to use relative paths without including the context root name?

You start tomcat from some directory - which is the $cwd for tomcat. You can specify any path relative to this $cwd.

suppose you have

home
- tomcat
 |_bin
- cssStore
 |_file.css

And suppose you start tomcat from ~/tomcat, using the command "bin/startup.sh".

~/tomcat becomes the home directory ($cwd) for tomcat

You can access "../cssStore/file.css" from class files in your servlet now

Hope that helps, - M.S.

Data binding to SelectedItem in a WPF Treeview

There is also a way to create XAML bindable SelectedItem property without using Interaction.Behaviors.

public static class BindableSelectedItemHelper
{
    #region Properties

    public static readonly DependencyProperty SelectedItemProperty = DependencyProperty.RegisterAttached("SelectedItem", typeof(object), typeof(BindableSelectedItemHelper),
        new FrameworkPropertyMetadata(null, OnSelectedItemPropertyChanged));

    public static readonly DependencyProperty AttachProperty = DependencyProperty.RegisterAttached("Attach", typeof(bool), typeof(BindableSelectedItemHelper), new PropertyMetadata(false, Attach));

    private static readonly DependencyProperty IsUpdatingProperty = DependencyProperty.RegisterAttached("IsUpdating", typeof(bool), typeof(BindableSelectedItemHelper));

    #endregion

    #region Implementation

    public static void SetAttach(DependencyObject dp, bool value)
    {
        dp.SetValue(AttachProperty, value);
    }

    public static bool GetAttach(DependencyObject dp)
    {
        return (bool)dp.GetValue(AttachProperty);
    }

    public static string GetSelectedItem(DependencyObject dp)
    {
        return (string)dp.GetValue(SelectedItemProperty);
    }

    public static void SetSelectedItem(DependencyObject dp, object value)
    {
        dp.SetValue(SelectedItemProperty, value);
    }

    private static bool GetIsUpdating(DependencyObject dp)
    {
        return (bool)dp.GetValue(IsUpdatingProperty);
    }

    private static void SetIsUpdating(DependencyObject dp, bool value)
    {
        dp.SetValue(IsUpdatingProperty, value);
    }

    private static void Attach(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        TreeListView treeListView = sender as TreeListView;
        if (treeListView != null)
        {
            if ((bool)e.OldValue)
                treeListView.SelectedItemChanged -= SelectedItemChanged;

            if ((bool)e.NewValue)
                treeListView.SelectedItemChanged += SelectedItemChanged;
        }
    }

    private static void OnSelectedItemPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        TreeListView treeListView = sender as TreeListView;
        if (treeListView != null)
        {
            treeListView.SelectedItemChanged -= SelectedItemChanged;

            if (!(bool)GetIsUpdating(treeListView))
            {
                foreach (TreeViewItem item in treeListView.Items)
                {
                    if (item == e.NewValue)
                    {
                        item.IsSelected = true;
                        break;
                    }
                    else
                       item.IsSelected = false;                        
                }
            }

            treeListView.SelectedItemChanged += SelectedItemChanged;
        }
    }

    private static void SelectedItemChanged(object sender, RoutedEventArgs e)
    {
        TreeListView treeListView = sender as TreeListView;
        if (treeListView != null)
        {
            SetIsUpdating(treeListView, true);
            SetSelectedItem(treeListView, treeListView.SelectedItem);
            SetIsUpdating(treeListView, false);
        }
    }
    #endregion
}

You can then use this in your XAML as:

<TreeView  helper:BindableSelectedItemHelper.Attach="True" 
           helper:BindableSelectedItemHelper.SelectedItem="{Binding SelectedItem, Mode=TwoWay}">

Link to a section of a webpage

Hashtags at the end of the URL bring a visitor to the element with the ID: e.g.

http://stackoverflow.com/questions/8424785/link-to-a-section-of-a-webpage#answers 

Would bring you to where the DIV with the ID 'answers' begins. Also, you can use the name attribute in anchor tags, to create the same effect.

Resource

Bootstrap Align Image with text

You have two choices, either correct your markup so that it uses correct elements and utilizes the Bootstrap grid system:

_x000D_
_x000D_
@import url('http://getbootstrap.com/dist/css/bootstrap.css');
_x000D_
<div class="container">_x000D_
     <h1>About Me</h1>_x000D_
    <div class="row">_x000D_
        <div class="col-md-4">_x000D_
            <div class="imgAbt">_x000D_
                <img width="220" height="220" src="img/me.jpg" />_x000D_
            </div>_x000D_
        </div>_x000D_
        <div class="col-md-8">_x000D_
            <p>Lots of text here...With the four tiers of grids available you're bound to run into issues where, at certain breakpoints, your columns don't clear quite right as one is taller than the other. To fix that, use a combination of a .clearfix and o</p>_x000D_
        </div>_x000D_
    </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Or, if you wish the text to closely wrap the image, change your markup to:

_x000D_
_x000D_
@import url('http://getbootstrap.com/dist/css/bootstrap.css');
_x000D_
<div class="container">_x000D_
    <h1>About Me</h1>_x000D_
    <div class="row">_x000D_
        <div class="col-md-12">_x000D_
            <img style='float:left;width:200px;height:200px; margin-right:10px;' src="img/me.jpg" />_x000D_
            <p>Lots of text here...With the four tiers of grids available you're bound to run into issues where, at certain breakpoints, your columns don't clear quite right as one is taller than the other. To fix that, use a combination of a .clearfix and o</p>_x000D_
        </div>_x000D_
    </div>
_x000D_
_x000D_
_x000D_

Accessing UI (Main) Thread safely in WPF

Use [Dispatcher.Invoke(DispatcherPriority, Delegate)] to change the UI from another thread or from background.

Step 1. Use the following namespaces

using System.Windows;
using System.Threading;
using System.Windows.Threading;

Step 2. Put the following line where you need to update UI

Application.Current.Dispatcher.Invoke(DispatcherPriority.Background, new ThreadStart(delegate
{
    //Update UI here
}));

Syntax

[BrowsableAttribute(false)]
public object Invoke(
  DispatcherPriority priority,
  Delegate method
)

Parameters

priority

Type: System.Windows.Threading.DispatcherPriority

The priority, relative to the other pending operations in the Dispatcher event queue, the specified method is invoked.

method

Type: System.Delegate

A delegate to a method that takes no arguments, which is pushed onto the Dispatcher event queue.

Return Value

Type: System.Object

The return value from the delegate being invoked or null if the delegate has no return value.

Version Information

Available since .NET Framework 3.0

How to equalize the scales of x-axis and y-axis in Python matplotlib?

Try something like:

import pylab as p
p.plot(x,y)
p.axis('equal')
p.show()

Error when using scp command "bash: scp: command not found"

Make sure the scp command is available on both sides - both on the client and on the server.

If this is Fedora or Red Hat Enterprise Linux and clones (CentOS), make sure this package is installed:

    yum -y install openssh-clients

If you work with Debian or Ubuntu and clones, install this package:

    apt-get install openssh-client

Again, you need to do this both on the server and the client, otherwise you can encounter "weird" error messages on your client: scp: command not found or similar although you have it locally. This already confused thousands of people, I guess :)

"Cannot open include file: 'config-win.h': No such file or directory" while installing mysql-python

The accepted answer is out of date. Some of the suggestions were already incorporated in the package, and I was still getting the error about missing config-win.h & mysqlclient.lib.

  • Install mysql-connector-c-6.0.2-win32.msi

    There's a zip file for the conenctor too but that didn't work because mysqlclient.lib is in lib directory whereas the installer expects it in lib/opt. Instead of hacking site.cfg or setup_windows.py, the msi does the job.

  • pip install mysql-python

P.S. Since I don't use MySQL anymore, my answer may be out of date as well.

jQuery get textarea text

you can get textarea data by name and id

// by name
<textarea name="comment"></textarea>
let text_area_data = $('textarea[name="comment"]').val();

// by id
<textarea id="comment" name="comment"></textarea>
let text_area_data = $('textarea#comment').val();

What is the difference between Serialization and Marshaling?

From the Marshalling (computer science) Wikipedia article:

The term "marshal" is considered to be synonymous with "serialize" in the Python standard library1, but the terms are not synonymous in the Java-related RFC 2713:

To "marshal" an object means to record its state and codebase(s) in such a way that when the marshalled object is "unmarshalled", a copy of the original object is obtained, possibly by automatically loading the class definitions of the object. You can marshal any object that is serializable or remote. Marshalling is like serialization, except marshalling also records codebases. Marshalling is different from serialization in that marshalling treats remote objects specially. (RFC 2713)

To "serialize" an object means to convert its state into a byte stream in such a way that the byte stream can be converted back into a copy of the object.

So, marshalling also saves the codebase of an object in the byte stream in addition to its state.

Find a string between 2 known values

A Regex approach using lazy match and back-reference:

foreach (Match match in Regex.Matches(
        "morenonxmldata<tag1>0002</tag1>morenonxmldata<tag2>abc</tag2>asd",
        @"<([^>]+)>(.*?)</\1>"))
{
    Console.WriteLine("{0}={1}",
        match.Groups[1].Value,
        match.Groups[2].Value);
}

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

SQL is a declarative language, not a procedural language. That is, you construct a SQL statement to describe the results that you want. You are not telling the SQL engine how to do the work.

As a general rule, it is a good idea to let the SQL engine and SQL optimizer find the best query plan. There are many person-years of effort that go into developing a SQL engine, so let the engineers do what they know how to do.

Of course, there are situations where the query plan is not optimal. Then you want to use query hints, restructure the query, update statistics, use temporary tables, add indexes, and so on to get better performance.

As for your question. The performance of CTEs and subqueries should, in theory, be the same since both provide the same information to the query optimizer. One difference is that a CTE used more than once could be easily identified and calculated once. The results could then be stored and read multiple times. Unfortunately, SQL Server does not seem to take advantage of this basic optimization method (you might call this common subquery elimination).

Temporary tables are a different matter, because you are providing more guidance on how the query should be run. One major difference is that the optimizer can use statistics from the temporary table to establish its query plan. This can result in performance gains. Also, if you have a complicated CTE (subquery) that is used more than once, then storing it in a temporary table will often give a performance boost. The query is executed only once.

The answer to your question is that you need to play around to get the performance you expect, particularly for complex queries that are run on a regular basis. In an ideal world, the query optimizer would find the perfect execution path. Although it often does, you may be able to find a way to get better performance.

Progress during large file copy (Copy-Item & Write-Progress?)

I haven't heard about progress with Copy-Item. If you don't want to use any external tool, you can experiment with streams. The size of buffer varies, you may try different values (from 2kb to 64kb).

function Copy-File {
    param( [string]$from, [string]$to)
    $ffile = [io.file]::OpenRead($from)
    $tofile = [io.file]::OpenWrite($to)
    Write-Progress -Activity "Copying file" -status "$from -> $to" -PercentComplete 0
    try {
        [byte[]]$buff = new-object byte[] 4096
        [long]$total = [int]$count = 0
        do {
            $count = $ffile.Read($buff, 0, $buff.Length)
            $tofile.Write($buff, 0, $count)
            $total += $count
            if ($total % 1mb -eq 0) {
                Write-Progress -Activity "Copying file" -status "$from -> $to" `
                   -PercentComplete ([long]($total * 100 / $ffile.Length))
            }
        } while ($count -gt 0)
    }
    finally {
        $ffile.Dispose()
        $tofile.Dispose()
        Write-Progress -Activity "Copying file" -Status "Ready" -Completed
    }
}

phpMyAdmin says no privilege to create database, despite logged in as root user

sudo mysql

enter your (LINUX) account password

grant create on *.* to user@localhost;

FLUSH PRIVILEGES;

Angularjs - display current date

A solution similar to the one of @Nick G. by using filter, but make the parameter meaningful:

Implement an filter called relativedate which calculate the date relative to current date by the given parameter as diff. As a result, (0 | relativedate) means today and (1 | relativedate) means tomorrow.

.filter('relativedate', ['$filter', function ($filter) {
  return function (rel, format) {
    let date = new Date();
    date.setDate(date.getDate() + rel);
    return $filter('date')(date, format || 'yyyy-MM-dd')
  };
}]);

and your html:

<div ng-app="myApp">
    <div>Yesterday: {{-1 | relativedate}}</div>
    <div>Today: {{0 | relativedate}}</div>
    <div>Tomorrow: {{1 | relativedate}}</div>
</div>

How do you clear a slice in Go?

Setting the slice to nil is the best way to clear a slice. nil slices in go are perfectly well behaved and setting the slice to nil will release the underlying memory to the garbage collector.

See playground

package main

import (
    "fmt"
)

func dump(letters []string) {
    fmt.Println("letters = ", letters)
    fmt.Println(cap(letters))
    fmt.Println(len(letters))
    for i := range letters {
        fmt.Println(i, letters[i])
    }
}

func main() {
    letters := []string{"a", "b", "c", "d"}
    dump(letters)
    // clear the slice
    letters = nil
    dump(letters)
    // add stuff back to it
    letters = append(letters, "e")
    dump(letters)
}

Prints

letters =  [a b c d]
4
4
0 a
1 b
2 c
3 d
letters =  []
0
0
letters =  [e]
1
1
0 e

Note that slices can easily be aliased so that two slices point to the same underlying memory. The setting to nil will remove that aliasing.

This method changes the capacity to zero though.

How to get the list of all database users

EXEC sp_helpuser

or

SELECT * FROM sysusers

Both of these select all the users of the current database (not the server).

Accessing Redux state in an action creator?

I would like to suggest yet another alternative that I find the cleanest, but it requires react-redux or something simular - also I'm using a few other fancy features along the way:

// actions.js
export const someAction = (items) => ({
    type: 'SOME_ACTION',
    payload: {items},
});
// Component.jsx
import {connect} from "react-redux";

const Component = ({boundSomeAction}) => (<div
    onClick={boundSomeAction}
/>);

const mapState = ({otherReducer: {items}}) => ({
    items,
});

const mapDispatch = (dispatch) => bindActionCreators({
    someAction,
}, dispatch);

const mergeProps = (mappedState, mappedDispatches) => {
    // you can only use what gets returned here, so you dont have access to `items` and 
    // `someAction` anymore
    return {
        boundSomeAction: () => mappedDispatches.someAction(mappedState.items),
    }
});

export const ConnectedComponent = connect(mapState, mapDispatch, mergeProps)(Component);
// (with  other mapped state or dispatches) Component.jsx
import {connect} from "react-redux";

const Component = ({boundSomeAction, otherAction, otherMappedState}) => (<div
    onClick={boundSomeAction}
    onSomeOtherEvent={otherAction}
>
    {JSON.stringify(otherMappedState)}
</div>);

const mapState = ({otherReducer: {items}, otherMappedState}) => ({
    items,
    otherMappedState,
});

const mapDispatch = (dispatch) => bindActionCreators({
    someAction,
    otherAction,
}, dispatch);

const mergeProps = (mappedState, mappedDispatches) => {
    const {items, ...remainingMappedState} = mappedState;
    const {someAction, ...remainingMappedDispatch} = mappedDispatch;
    // you can only use what gets returned here, so you dont have access to `items` and 
    // `someAction` anymore
    return {
        boundSomeAction: () => someAction(items),
        ...remainingMappedState,
        ...remainingMappedDispatch,
    }
});

export const ConnectedComponent = connect(mapState, mapDispatch, mergeProps)(Component);

If you want to reuse this you'll have to extract the specific mapState, mapDispatch and mergeProps into functions to reuse elsewhere, but this makes dependencies perfectly clear.

Razor-based view doesn't see referenced assemblies

in spacename models, yourClassModel, add public before name class

public class yourClassModel{
    prop
}

How do you 'redo' changes after 'undo' with Emacs?

For those wanting to have the more common undo/redo functionality, someone has written undo-tree.el. It provides the look and feel of non-Emacs undo, but provides access to the entire 'tree' of undo history.

I like Emacs' built-in undo system, but find this package to be very intuitive.

Here's the commentary from the file itself:

Emacs has a powerful undo system. Unlike the standard undo/redo system in most software, it allows you to recover any past state of a buffer (whereas the standard undo/redo system can lose past states as soon as you redo). However, this power comes at a price: many people find Emacs' undo system confusing and difficult to use, spawning a number of packages that replace it with the less powerful but more intuitive undo/redo system.

Both the loss of data with standard undo/redo, and the confusion of Emacs' undo, stem from trying to treat undo history as a linear sequence of changes. It's not. The `undo-tree-mode' provided by this package replaces Emacs' undo system with a system that treats undo history as what it is: a branching tree of changes. This simple idea allows the more intuitive behaviour of the standard undo/redo system to be combined with the power of never losing any history. An added side bonus is that undo history can in some cases be stored more efficiently, allowing more changes to accumulate before Emacs starts discarding history.

How do I populate a JComboBox with an ArrayList?

DefaultComboBoxModel dml= new DefaultComboBoxModel();
for (int i = 0; i < <ArrayList>.size(); i++) {
  dml.addElement(<ArrayList>.get(i).getField());
}

<ComboBoxName>.setModel(dml);

Understandable code.Edit<> with type as required.

How to check if a String contains any of some strings

Here's a LINQ solution which is virtually the same but more scalable:

new[] { "a", "b", "c" }.Any(c => s.Contains(c))

How do you sign a Certificate Signing Request with your Certification Authority?

In addition to answer of @jww, I would like to say that the configuration in openssl-ca.cnf,

default_days     = 1000         # How long to certify for

defines the default number of days the certificate signed by this root-ca will be valid. To set the validity of root-ca itself you should use '-days n' option in:

openssl req -x509 -days 3000 -config openssl-ca.cnf -newkey rsa:4096 -sha256 -nodes -out cacert.pem -outform PEM

Failing to do so, your root-ca will be valid for only the default one month and any certificate signed by this root CA will also have validity of one month.

Eloquent ->first() if ->exists()

(ps - I couldn't comment) I think your best bet is something like you've done, or similar to:

$user = User::where('mobile', Input::get('mobile'));
$user->exists() and $user = $user->first();

Oh, also: count() instead if exists but this could be something used after get.

Convert list to array in Java

Example taken from this page: http://www.java-examples.com/copy-all-elements-java-arraylist-object-array-example

import java.util.ArrayList;

public class CopyElementsOfArrayListToArrayExample {

  public static void main(String[] args) {
    //create an ArrayList object
    ArrayList arrayList = new ArrayList();

    //Add elements to ArrayList
    arrayList.add("1");
    arrayList.add("2");
    arrayList.add("3");
    arrayList.add("4");
    arrayList.add("5");

    /*
      To copy all elements of java ArrayList object into array use
      Object[] toArray() method.
    */

    Object[] objArray = arrayList.toArray();

    //display contents of Object array
    System.out.println("ArrayList elements are copied into an Array.
                                                  Now Array Contains..");
    for(int index=0; index < objArray.length ; index++)
      System.out.println(objArray[index]);
  }
}

/*
Output would be
ArrayList elements are copied into an Array. Now Array Contains..
1
2
3
4
5

How to uninstall with msiexec using product id guid without .msi file present

msiexec.exe /x "{588A9A11-1E20-4B91-8817-2D36ACBBBF9F}" /q 

ORA-01882: timezone region not found

In Netbeans,

  1. Right-click your project -> Properties
  2. Go to Run (under Categories)
  3. Enter -Duser.timezone=UTC or -Duser.timezone=GMT under VM Options.

Click Ok, then re-run your program.

Note: You can as well set to other timestones besides UTC & GMT.

Pandas get the most frequent values of a column

To get the top five most common names:

dataframe['name'].value_counts().head()

Convert Java object to XML string

Here is a util class for marshaling and unmarshaling objects. In my case it was a nested class, so I made it static JAXBUtils.

import javax.xml.bind.JAXB;
import java.io.StringReader;
import java.io.StringWriter;

public class JAXBUtils
{
    /**
     * Unmarshal an XML string
     * @param xml     The XML string
     * @param type    The JAXB class type.
     * @return The unmarshalled object.
     */
    public <T> T unmarshal(String xml, Class<T> type)
    {
        StringReader reader = new StringReader(xml);
        return javax.xml.bind.JAXB.unmarshal(reader, type);
    }

    /**
     * Marshal an Object to XML.
     * @param object    The object to marshal.
     * @return The XML string representation of the object.
     */
    public String marshal(Object object)
    {
        StringWriter stringWriter = new StringWriter();
        JAXB.marshal(object, stringWriter);
        return stringWriter.toString();
    }
}

Only local connections are allowed Chrome and Selenium webdriver

I was also getting the same issue. I resolved this issue by updating the chromedriver. So if anyone is facing same issue with chrome browser just update your chromedriver.

Propagate all arguments in a bash shell script

#!/usr/bin/env bash
while [ "$1" != "" ]; do
  echo "Received: ${1}" && shift;
done;

Just thought this may be a bit more useful when trying to test how args come into your script

When is a timestamp (auto) updated?

An auto-updated column is automatically updated to the current timestamp when the value of any other column in the row is changed from its current value. An auto-updated column remains unchanged if all other columns are set to their current values.

To explain it let's imagine you have only one row:

-------------------------------
| price | updated_at          |
-------------------------------
|  2    | 2018-02-26 16:16:17 |
-------------------------------

Now, if you run the following update column:

 update my_table
 set price = 2

it will not change the value of updated_at, since price value wasn't actually changed (it was already 2).

But if you have another row with price value other than 2, then the updated_at value of that row (with price <> 3) will be updated to CURRENT_TIMESTAMP.

Get the selected value in a dropdown using jQuery.

Try:

jQuery("#availability option:selected").val();

Or to get the text of the option, use text():

jQuery("#availability option:selected").text();

More Info:

Check if any type of files exist in a directory using BATCH script

For files in a directory, you can use things like:

if exist *.csv echo "csv file found"

or

if not exist *.csv goto nofile

How to configure WAMP (localhost) to send email using Gmail?

As an alternative to PHPMailer, Pear's Mail and others you could use the Zend's library

  $config = array('auth' => 'login',
                   'ssl' => 'ssl',
                   'port'=> 465,
                   'username' => '[email protected]',
                   'password' => 'XXXXXXX');

 $transport = new Zend_Mail_Transport_Smtp('smtp.gmail.com', $config);
 $mail = new Zend_Mail();
 $mail->setBodyText('This is the text of the mail.');
 $mail->setFrom('[email protected]', 'Some Sender');
 $mail->addTo('[email protected]', 'Some Recipient');
 $mail->setSubject('TestSubj');
 $mail->send($transport); 

That is my set up in localhost server and I can able to see incoming mail to my mail box.

What is a pre-revprop-change hook in SVN, and how do I create it?

Thanks #patmortech

And I added your code which "only the same user can change his code".

:: Only allow editing of the same user.
for /f "tokens=*" %%a in ( 
'"%VISUALSVN_SERVER%\bin\svnlook.exe" author -r %revision% %repository%') do ( 
set orgAuthor=%%a
)
if /I not "%userName%" == "%orgAuthor%" goto ERROR_SAME_USER

GCM with PHP (Google Cloud Messaging)

use this

 function pnstest(){

                $data = array('post_id'=>'12345','title'=>'A Blog post', 'message' =>'test msg');

                $url = 'https://fcm.googleapis.com/fcm/send';

                $server_key = 'AIzaSyDVpDdS7EyNgMUpoZV6sI2p-cG';

                $target ='fO3JGJw4CXI:APA91bFKvHv8wzZ05w2JQSor6D8lFvEGE_jHZGDAKzFmKWc73LABnumtRosWuJx--I4SoyF1XQ4w01P77MKft33grAPhA8g-wuBPZTgmgttaC9U4S3uCHjdDn5c3YHAnBF3H';

                $fields = array();
                $fields['data'] = $data;
                if(is_array($target)){
                    $fields['registration_ids'] = $target;
                }else{
                    $fields['to'] = $target;
                }

                //header with content_type api key
                $headers = array(
                    'Content-Type:application/json',
                  'Authorization:key='.$server_key
                );

                $ch = curl_init();
                curl_setopt($ch, CURLOPT_URL, $url);
                curl_setopt($ch, CURLOPT_POST, true);
                curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
                curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
                curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
                curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
                curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($fields));
                $result = curl_exec($ch);
                if ($result === FALSE) {
                    die('FCM Send Error: ' . curl_error($ch));
                }
                curl_close($ch);
                return $result;

}

How to open a web page automatically in full screen mode

Only works in IE:

window.open ("mapage.html","","fullscreen=yes");  
window.open('','_parent','');  
window.close();

Converting JavaScript object with numeric keys into array

_x000D_
_x000D_
var JsonObj = {_x000D_
  "0": "1",_x000D_
  "1": "2",_x000D_
  "2": "3",_x000D_
  "3": "4"_x000D_
};_x000D_
_x000D_
var array = [];_x000D_
for (var i in JsonObj) {_x000D_
  if (JsonObj.hasOwnProperty(i) && !isNaN(+i)) {_x000D_
    array[+i] = JsonObj[i];_x000D_
  }_x000D_
}_x000D_
_x000D_
console.log(array)
_x000D_
_x000D_
_x000D_

DEMO

How to get attribute of element from Selenium?

You are probably looking for get_attribute(). An example is shown here as well

def test_chart_renders_from_url(self):
    url = 'http://localhost:8000/analyse/'
    self.browser.get(url)
    org = driver.find_element_by_id('org')
    # Find the value of org?
    val = org.get_attribute("attribute name")

Calculate relative time in C#

I think there is already a number of answers related to this post, but one can use this which is easy to use just like plugin and also easily readable for programmers. Send your specific date, and get its value in string form:

public string RelativeDateTimeCount(DateTime inputDateTime)
{
    string outputDateTime = string.Empty;
    TimeSpan ts = DateTime.Now - inputDateTime;

    if (ts.Days > 7)
    { outputDateTime = inputDateTime.ToString("MMMM d, yyyy"); }

    else if (ts.Days > 0)
    {
        outputDateTime = ts.Days == 1 ? ("about 1 Day ago") : ("about " + ts.Days.ToString() + " Days ago");
    }
    else if (ts.Hours > 0)
    {
        outputDateTime = ts.Hours == 1 ? ("an hour ago") : (ts.Hours.ToString() + " hours ago");
    }
    else if (ts.Minutes > 0)
    {
        outputDateTime = ts.Minutes == 1 ? ("1 minute ago") : (ts.Minutes.ToString() + " minutes ago");
    }
    else outputDateTime = "few seconds ago";

    return outputDateTime;
}

This declaration has no storage class or type specifier in C++

Calling m.check(side), meaning you are running actual code, but you can't run code outside main() - you can only define variables. In C++, code can only appear inside function bodies or in variable initializes.

6 digits regular expression

^[0-9]{1,6}$ should do it. I don't know VB.NET good enough to know if it's the same there.

For examples, have a look at the Wikipedia.

Base table or view not found: 1146 Table Laravel 5

Check your migration file, maybe you are using Schema::table, like this:

Schema::table('table_name', function ($table)  {
    // ...
});

If you want to create a new table you must use Schema::create:

Schema::create('table_name', function ($table)  {
    // ...
});

Java generics: multiple generic parameters?

You can declare multiple type variables on a type or method. For example, using type parameters on the method:

<P, Q> int f(Set<P>, Set<Q>) {
  return 0;
}

How to show/hide JPanels in a JFrame?

You can hide a JPanel by calling setVisible(false). For example:

public static void main(String args[]){
    JFrame f = new JFrame();
    f.setLayout(new BorderLayout());
    final JPanel p = new JPanel();
    p.add(new JLabel("A Panel"));
    f.add(p, BorderLayout.CENTER);

    //create a button which will hide the panel when clicked.
    JButton b = new JButton("HIDE");
    b.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){
                p.setVisible(false);
        }
    });

    f.add(b,BorderLayout.SOUTH);
    f.pack();
    f.setVisible(true);
}

How do I use a regular expression to match any string, but at least 3 characters?

Try this .{3,} this will match any characher except new line (\n)

SELECT inside a COUNT

You can move the count() inside your sub-select:

SELECT a AS current_a, COUNT(*) AS b,
   ( SELECT COUNT(*) FROM t WHERE a = current_a AND c = 'const' ) as d,
   from t group by a order by b desc

varbinary to string on SQL Server

The following expression worked for me:

SELECT CONVERT(VARCHAR(1000), varbinary_value, 2);

Here are more details on the choice of style (the third parameter).

Android: How to change CheckBox size?

Here was what I did, first set:

android:button="@null"

and also set

android:drawableLeft="@drawable/selector_you_defined_for_your_checkbox"

then in your Java code:

Drawable d = mCheckBox.getCompoundDrawables()[0];
d.setBounds(0, 0, width_you_prefer, height_you_prefer);
mCheckBox.setCompoundDrawables(d, null, null, null);

It works for me, and hopefully it will work for you!

How to clear a notification in Android

Use the following code to cancel a Notification:

NotificationManager notificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.cancel(NOTIFICATION_ID);

In this code there is alway the same id used for notifications. If you have different notifications that need to be canceled you have to save the ids that you used to create the Notification.

ImportError: No module named 'MySQL'

run

pip list 

to see list of packages you have installed. If it has mysql-connector-python then that is fine.

Remember not to name your python script file as mysql.py

How to force addition instead of concatenation in javascript

The following statement appends the value to the element with the id of response

$('#response').append(total);

This makes it look like you are concatenating the strings, but you aren't, you're actually appending them to the element

change that to

$('#response').text(total);

You need to change the drop event so that it replaces the value of the element with the total, you also need to keep track of what the total is, I suggest something like the following

$(function() {
    var data = [];
    var total = 0;

    $( "#draggable1" ).draggable();
    $( "#draggable2" ).draggable();
    $( "#draggable3" ).draggable();

    $("#droppable_box").droppable({
        drop: function(event, ui) {
        var currentId = $(ui.draggable).attr('id');
        data.push($(ui.draggable).attr('id'));

        if(currentId == "draggable1"){
            var myInt1 = parseFloat($('#MealplanCalsPerServing1').val());
        }
        if(currentId == "draggable2"){
            var myInt2 = parseFloat($('#MealplanCalsPerServing2').val());
        }
        if(currentId == "draggable3"){
            var myInt3 = parseFloat($('#MealplanCalsPerServing3').val());
        }
        if ( typeof myInt1 === 'undefined' || !myInt1 ) {
            myInt1 = parseInt(0);
        }
        if ( typeof myInt2 === 'undefined' || !myInt2){
            myInt2 = parseInt(0);
        }
        if ( typeof myInt3 === 'undefined' || !myInt3){
        myInt3 = parseInt(0);
        }
        total += parseFloat(myInt1 + myInt2 + myInt3);
        $('#response').text(total);
        }
    });

    $('#myId').click(function(event) {
        $.post("process.php", ({ id: data }), function(return_data, status) {
            alert(data);
            //alert(total);
        });
    });
});

I moved the var total = 0; statement out of the drop event and changed the assignment statment from this

total = parseFloat(myInt1 + myInt2 + myInt3);

to this

total += parseFloat(myInt1 + myInt2 + myInt3);

Here is a working example http://jsfiddle.net/axrwkr/RCzGn/

Managing jQuery plugin dependency in webpack

For global access to jquery then several options exist. In my most recent webpack project, I wanted global access to jquery so I added the following to my plugins declarations:

 plugins: [
    new webpack.ProvidePlugin({
      $: "jquery",
      jQuery: "jquery"
    })
  ]

This then means that jquery is accessible from within the JavaScript source code via global references $ and jQuery.

Of course, you need to have also installed jquery via npm:

$ npm i jquery --save

For a working example of this approach please feel free to fork my app on github

How to read PDF files using Java?

with Apache PDFBox it goes like this:

PDDocument document = PDDocument.load(new File("test.pdf"));
if (!document.isEncrypted()) {
    PDFTextStripper stripper = new PDFTextStripper();
    String text = stripper.getText(document);
    System.out.println("Text:" + text);
}
document.close();

Java regex capturing groups indexes

For The Rest Of Us

Here is a simple and clear example of how this works

Regex: ([a-zA-Z0-9]+)([\s]+)([a-zA-Z ]+)([\s]+)([0-9]+)

String: "!* UserName10 John Smith 01123 *!"

group(0): UserName10 John Smith 01123
group(1): UserName10
group(2):  
group(3): John Smith
group(4):  
group(5): 01123

As you can see, I have created FIVE groups which are each enclosed in parentheses.

I included the !* and *! on either side to make it clearer. Note that none of those characters are in the RegEx and therefore will not be produced in the results. Group(0) merely gives you the entire matched string (all of my search criteria in one single line). Group 1 stops right before the first space because the space character was not included in the search criteria. Groups 2 and 4 are simply the white space, which in this case is literally a space character, but could also be a tab or a line feed etc. Group 3 includes the space because I put it in the search criteria ... etc.

Hope this makes sense.

Maven 3 warnings about build.plugins.plugin.version

get the latest version information from:

https://mvnrepository.com/artifact/org.apache.maven.plugins/maven-compiler-plugin

click on the latest version (or the one you'd like to use) and you'll see the the dependency info (as of 2019-05 it's 3.8.1):

<!-- https://mvnrepository.com/artifact/org.apache.maven.plugins/maven-compiler-plugin -->
<dependency>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-compiler-plugin</artifactId>
  <version>3.8.1</version>
</dependency>

you might want to use the version tag and the comment for your plugin tag.

<!-- https://mvnrepository.com/artifact/org.apache.maven.plugins/maven-compiler-plugin -->
<plugin>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.8.1</version>
    <configuration>
        <source />
        <target />
    </configuration>
</plugin>

if you like you can modify your pom to have the version information in the properties tag as outlined in another answer.

How to get JSON response from http.Get

You need upper case property names in your structs in order to be used by the json packages.

Upper case property names are exported properties. Lower case property names are not exported.

You also need to pass the your data object by reference (&data).

package main

import "os"
import "fmt"
import "net/http"
import "io/ioutil"
import "encoding/json"

type tracks struct {
    Toptracks []toptracks_info
}

type toptracks_info struct {
    Track []track_info
    Attr  []attr_info
}

type track_info struct {
    Name       string
    Duration   string
    Listeners  string
    Mbid       string
    Url        string
    Streamable []streamable_info
    Artist     []artist_info
    Attr       []track_attr_info
}

type attr_info struct {
    Country    string
    Page       string
    PerPage    string
    TotalPages string
    Total      string
}

type streamable_info struct {
    Text      string
    Fulltrack string
}

type artist_info struct {
    Name string
    Mbid string
    Url  string
}

type track_attr_info struct {
    Rank string
}

func get_content() {
    // json data
    url := "http://ws.audioscrobbler.com/2.0/?method=geo.gettoptracks&api_key=c1572082105bd40d247836b5c1819623&format=json&country=Netherlands"

    res, err := http.Get(url)

    if err != nil {
        panic(err.Error())
    }

    body, err := ioutil.ReadAll(res.Body)

    if err != nil {
        panic(err.Error())
    }

    var data tracks
    json.Unmarshal(body, &data)
    fmt.Printf("Results: %v\n", data)
    os.Exit(0)
}

func main() {
    get_content()
}

setOnItemClickListener on custom ListView

I too had that same problem.. If we think logically little bit we can get the answer.. It worked for me very well.. I hope u will get it..

  1. listviewdemo.xml

    <ListView
        android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:paddingBottom="30dp"
        android:paddingLeft="10dp"
        android:paddingRight="10dp" />
    

  2. listviewcontent.xml - note that TextView - android:id="@+id/txtLstItem"

    <LinearLayout
        android:id="@+id/listviewcontentlayout"
        android:layout_width="0dp"
        android:layout_height="fill_parent"
        android:layout_weight="1"
        android:orientation="horizontal">
    
        <ImageView
            android:id="@+id/img1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="6dp" />
    
        <LinearLayout
            android:layout_width="0dp"
            android:layout_height="fill_parent"
            android:layout_weight="1"
            android:orientation="vertical">
    
            <TextView
                android:id="@+id/txtLstItem"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:gravity="left"
                android:shadowColor="@android:color/black"
                android:shadowRadius="5"
                android:textColor="@android:color/white" />
    
        </LinearLayout>
    
        <ImageView
            android:id="@+id/img2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="6dp" />
    </LinearLayout>
    

  3. ListViewActivity.java - Note that view.findViewById(R.id.txtLstItem) - as we setting the value to TextView by setText() method we getting text from TextView by View object returned by onItemClick method. OnItemClick() returns the current view.

    TextView v=(TextView) view.findViewById(R.id.txtLstItem);
    Toast.makeText(getApplicationContext(), "selected Item Name is "+v.getText(), Toast.LENGTH_LONG).show();**
    

    Using this simple logic we can get other values like CheckBox, RadioButton, ImageView etc.

    ListView List = (ListView) findViewById(R.id.listview);
    cursor = cr.query(CONTENT_URI,projection,null,null,null);
    adapter = new ListViewCursorAdapter(ListViewActivity.this, R.layout.listviewcontent, cursor, from, to);
    
    cursor.moveToFirst();
    
    // Let activity manage the cursor
    startManagingCursor(cursor);
    
    List.setAdapter(adapter);
    List.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick (AdapterView < ? > adapter, View view,int position, long arg){
                // TODO Auto-generated method stub
                TextView v = (TextView) view.findViewById(R.id.txtLstItem);
                Toast.makeText(getApplicationContext(), "selected Item Name is " + v.getText(), Toast.LENGTH_LONG).show();
            }
        }
    );
    

Continuous CSS rotation animation on hover, animated back to 0deg on hover out

It took a few tries, but I was able to get your jsFiddle to work (for Webkit only).

There's still an issue with the animation speed when the user re-enters the div.

Basically, just set the current rotation value to a variable, then do some calculations on that value (to convert to degrees), then set that value back to the element on mouse move and mouse enter.

Check out the jsFiddle: http://jsfiddle.net/4Vz63/46/

Check out this article for more information, including how to add cross-browser compatibility: http://css-tricks.com/get-value-of-css-rotation-through-javascript/

Get random boolean in Java

Why not use the Random class, which has a method nextBoolean:

import java.util.Random;

/** Generate 10 random booleans. */
public final class MyProgram {

  public static final void main(String... args){

    Random randomGenerator = new Random();
    for (int idx = 1; idx <= 10; ++idx){
      boolean randomBool = randomGenerator.nextBoolean();
      System.out.println("Generated : " + randomBool);
    }
  }
}

jquery <a> tag click event

<a href="javascript:void(0)" class="aaf" id="users_id">add as a friend</a>

on jquery

$('.aaf').on("click",function(){
  var usersid =  $(this).attr("id");
  //post code
})

//other method is to use the data attribute

<a href="javascript:void(0)" class="aaf" data-id="102" data-username="sample_username">add as a friend</a>

on jquery

$('.aaf').on("click",function(){
    var usersid =  $(this).data("id");
    var username = $(this).data("username");
})

'mvn' is not recognized as an internal or external command, operable program or batch file

Go to the shell (cmd for windows) and set the path variable manually from there. It works often from there. Read more at http://www.howtogeek.com/118594/how-to-edit-your-system-path-for-easy-command-line-access/

Changing Java Date one hour back

Just subtract the number of milliseconds in an hour from the date.

currentDate.setTime(currentDate.getTime() - 3600 * 1000));

connect to host localhost port 22: Connection refused

You may should edit your /etc/hosts. For example if my hostname is ub0, but the hostname in /etc/hosts is localhost, it may occur

connect to host ub0 port 22: Connection refused

Because the hostname in /etc/hosts is localhost not ub0.

So, you should be careful the hostname when building up distributed clusters.

How to send email to multiple recipients using python smtplib?

It works for me.

import smtplib
from email.mime.text import MIMEText

s = smtplib.SMTP('smtp.uk.xensource.com')
s.set_debuglevel(1)
msg = MIMEText("""body""")
sender = '[email protected]'
recipients = '[email protected],[email protected]'
msg['Subject'] = "subject line"
msg['From'] = sender
msg['To'] = recipients
s.sendmail(sender, recipients.split(','), msg.as_string())

Limiting double to 3 decimal places

Good answers above- if you're looking for something reusable here is the code. Note that you might want to check the decimal places value, and this may overflow.

public static decimal TruncateToDecimalPlace(this decimal numberToTruncate, int decimalPlaces)
{
    decimal power = (decimal)(Math.Pow(10.0, (double)decimalPlaces));

    return Math.Truncate((power * numberToTruncate)) / power;
}

Http post and get request in angular 6

Update : In angular 7, they are the same as 6

In angular 6

the complete answer found in live example

  /** POST: add a new hero to the database */
  addHero (hero: Hero): Observable<Hero> {
 return this.http.post<Hero>(this.heroesUrl, hero, httpOptions)
  .pipe(
    catchError(this.handleError('addHero', hero))
  );
}
  /** GET heroes from the server */
 getHeroes (): Observable<Hero[]> {
return this.http.get<Hero[]>(this.heroesUrl)
  .pipe(
    catchError(this.handleError('getHeroes', []))
  );
}

it's because of pipeable/lettable operators which now angular is able to use tree-shakable and remove unused imports and optimize the app

some rxjs functions are changed

do -> tap
catch -> catchError
switch -> switchAll
finally -> finalize

more in MIGRATION

and Import paths

For JavaScript developers, the general rule is as follows:

rxjs: Creation methods, types, schedulers and utilities

import { Observable, Subject, asapScheduler, pipe, of, from, interval, merge, fromEvent } from 'rxjs';

rxjs/operators: All pipeable operators:

import { map, filter, scan } from 'rxjs/operators';

rxjs/webSocket: The web socket subject implementation

import { webSocket } from 'rxjs/webSocket';

rxjs/ajax: The Rx ajax implementation

import { ajax } from 'rxjs/ajax';

rxjs/testing: The testing utilities

import { TestScheduler } from 'rxjs/testing';

and for backward compatability you can use rxjs-compat

Error "File google-services.json is missing from module root folder. The Google Services Plugin cannot function without it"

Very Simple Just go to Tools->Firebase->Connect to firebase than click on sync now THIS WILL SURELY WORK.

Accessing clicked element in angularjs

While AngularJS allows you to get a hand on a click event (and thus a target of it) with the following syntax (note the $event argument to the setMaster function; documentation here: http://docs.angularjs.org/api/ng.directive:ngClick):

function AdminController($scope) {    
  $scope.setMaster = function(obj, $event){
    console.log($event.target);
  }
}

this is not very angular-way of solving this problem. With AngularJS the focus is on the model manipulation. One would mutate a model and let AngularJS figure out rendering.

The AngularJS-way of solving this problem (without using jQuery and without the need to pass the $event argument) would be:

<div ng-controller="AdminController">
    <ul class="list-holder">
        <li ng-repeat="section in sections" ng-class="{active : isSelected(section)}">
            <a ng-click="setMaster(section)">{{section.name}}</a>
        </li>
    </ul>
    <hr>
    {{selected | json}}
</div>

where methods in the controller would look like this:

$scope.setMaster = function(section) {
    $scope.selected = section;
}

$scope.isSelected = function(section) {
    return $scope.selected === section;
}

Here is the complete jsFiddle: http://jsfiddle.net/pkozlowski_opensource/WXJ3p/15/

Does --disable-web-security Work In Chrome Anymore?

Check if you have Chrome App Launcher. You can usually see it in your toolbar. It runs as a second instance of chrome, but unlike the browser, it auto-runs so is going to be running whenever you start your PC. Even though it isn't a browser view, it is a chrome instance which is enough to prevent your arguments from taking effect. Go to your task manager and you will probably have to kill 2 chrome processes.

Remove all elements contained in another array

Proper way to remove all elements contained in another array is to make source array same object by remove only elements:

Array.prototype.removeContained = function(array) {
  var i, results;
  i = this.length;
  results = [];
  while (i--) {
    if (array.indexOf(this[i]) !== -1) {
      results.push(this.splice(i, 1));
    }
  }
  return results;
};

Or CoffeeScript equivalent:

Array.prototype.removeContained = (array) ->
  i = @length
  @splice i, 1 while i-- when array.indexOf(@[i]) isnt -1

Testing inside chrome dev tools:

19:33:04.447 a=1
19:33:06.354 b=2
19:33:07.615 c=3
19:33:09.981 arr = [a,b,c]
19:33:16.460 arr1 = arr

19:33:20.317 arr1 === arr
19:33:20.331 true

19:33:43.592 arr.removeContained([a,c])
19:33:52.433 arr === arr1
19:33:52.438 true

Using Angular framework is the best way to keep pointer to source object when you update collections without large amount of watchers and reloads.

Java SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'") gives timezone as IST

From ISO 8601 String to Java Date Object

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
sdf.setTimeZone(TimeZone.getTimeZone("GMT"));
sdf.parse("2013-09-29T18:46:19Z"); //prints-> Mon Sep 30 02:46:19 CST 2013

if you don't set TimeZone.getTimeZone("GMT") then it will output Sun Sep 29 18:46:19 CST 2013

From Java Date Object to ISO 8601 String

And to convert Dateobject to ISO 8601 Standard (yyyy-MM-dd'T'HH:mm:ss'Z') use following code

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.US);
sdf.setTimeZone(TimeZone.getTimeZone("GMT"));           
System.out.println(sdf.format(new Date())); //-prints-> 2015-01-22T03:23:26Z

Also note that without ' ' at Z yyyy-MM-dd'T'HH:mm:ssZ prints 2015-01-22T03:41:02+0000

add elements to object array

If you can, use a List<Subject> instead of Subject[]... this will let you do Student.Subject.Add(new Subject()). If that is not possible, you'll have to resize your array... look at Array.Resize() at http://msdn.microsoft.com/en-us/library/bb348051.aspx

concat yesterdays date with a specific time

where date_dt = to_date(to_char(sysdate-1, 'YYYY-MM-DD') || ' 19:16:08', 'YYYY-MM-DD HH24:MI:SS') 

should work.

vector vs. list in STL

vector:

  • Contiguous memory.
  • Pre-allocates space for future elements, so extra space required beyond what's necessary for the elements themselves.
  • Each element only requires the space for the element type itself (no extra pointers).
  • Can re-allocate memory for the entire vector any time that you add an element.
  • Insertions at the end are constant, amortized time, but insertions elsewhere are a costly O(n).
  • Erasures at the end of the vector are constant time, but for the rest it's O(n).
  • You can randomly access its elements.
  • Iterators are invalidated if you add or remove elements to or from the vector.
  • You can easily get at the underlying array if you need an array of the elements.

list:

  • Non-contiguous memory.
  • No pre-allocated memory. The memory overhead for the list itself is constant.
  • Each element requires extra space for the node which holds the element, including pointers to the next and previous elements in the list.
  • Never has to re-allocate memory for the whole list just because you add an element.
  • Insertions and erasures are cheap no matter where in the list they occur.
  • It's cheap to combine lists with splicing.
  • You cannot randomly access elements, so getting at a particular element in the list can be expensive.
  • Iterators remain valid even when you add or remove elements from the list.
  • If you need an array of the elements, you'll have to create a new one and add them all to it, since there is no underlying array.

In general, use vector when you don't care what type of sequential container that you're using, but if you're doing many insertions or erasures to and from anywhere in the container other than the end, you're going to want to use list. Or if you need random access, then you're going to want vector, not list. Other than that, there are naturally instances where you're going to need one or the other based on your application, but in general, those are good guidelines.

How to output something in PowerShell

I think the following is a good exhibit of Echo vs. Write-Host. Notice how test() actually returns an array of ints, not a single int as one could easily be led to believe.

function test {
    Write-Host 123
    echo 456 # AKA 'Write-Output'
    return 789
}

$x = test

Write-Host "x of type '$($x.GetType().name)' = $x"

Write-Host "`$x[0] = $($x[0])"
Write-Host "`$x[1] = $($x[1])"

Terminal output of the above:

123
x of type 'Object[]' = 456 789
$x[0] = 456
$x[1] = 789

VSCode Change Default Terminal

I just type following keywords in the opened terminal;

  1. powershell
  2. bash
  3. cmd
  4. node
  5. python (or python3)

See details in the below image. (VSCode version 1.19.1 - windows 10 OS) enter image description here

It works on VS Code Mac as well. I tried it with VSCode (Version 1.20.1)

How can I plot separate Pandas DataFrames as subplots?

You can use the familiar Matplotlib style calling a figure and subplot, but you simply need to specify the current axis using plt.gca(). An example:

plt.figure(1)
plt.subplot(2,2,1)
df.A.plot() #no need to specify for first axis
plt.subplot(2,2,2)
df.B.plot(ax=plt.gca())
plt.subplot(2,2,3)
df.C.plot(ax=plt.gca())

etc...

How to return temporary table from stored procedure

A temp table can be created in the caller and then populated from the called SP.

  create table #GetValuesOutputTable(
     ...   
  );

  exec GetValues; -- populates #GetValuesOutputTable

  select * from #GetValuesOutputTable;

Some advantages of this approach over the "insert exec" is that it can be nested and that it can be used as input or output.

Some disadvantages are that the "argument" is not public, the table creation exists within each caller, and that the name of the table could collide with other temp objects. It helps when the temp table name closely matches the SP name and follows some convention.

Taking it a bit farther, for output only temp tables, the insert-exec approach and the temp table approach can be supported simultaneously by the called SP. This doesn't help too much for chaining SP's because the table still need to be defined in the caller but can help to simplify testing from the cmd line or when calling externally.

  -- The "called" SP
  declare
      @returnAsSelect bit = 0;

  if object_id('tempdb..#GetValuesOutputTable') is null
  begin
      set @returnAsSelect = 1;
      create table #GetValuesOutputTable(
         ...   
      );
  end

  -- populate the table

  if @returnAsSelect = 1
      select * from #GetValuesOutputTable;

How can I center a div within another div?

You need to set the width of the container (auto won't work):

#container {
    width: 640px; /* Can be in percentage also. */
    height: auto;
    margin: 0 auto;
    padding: 10px;
    position: relative;
}

The CSS reference by MDN explains it all.

Check out these links:

In action at jsFiddle.

How to crop(cut) text files based on starting and ending line-numbers in cygwin?

And if you simply want to cut part of a file - say from line 26 to 142 - and input it to a newfile : cat file-to-cut.txt | sed -n '26,142p' >> new-file.txt

Error Code: 1062. Duplicate entry '1' for key 'PRIMARY'

The main reason why the error has been generated is because there is already an existing value of 1 for the column ID in which you define it as PRIMARY KEY (values are unique) in the table you are inserting.

Why not set the column ID as AUTO_INCREMENT?

CREATE  TABLE IF NOT EXISTS `PROGETTO`.`UFFICIO-INFORMAZIONI` (
  `ID` INT(11) NOT NULL AUTO_INCREMENT,
  `viale` VARCHAR(45) NULL ,
   .....

and when you are inserting record, you can now skip the column ID

INSERT INTO `PROGETTO`.`UFFICIO-INFORMAZIONI` (`viale`, `num_civico`, ...) 
VALUES ('Viale Cogel ', '120', ...)

How to fix 'Unchecked runtime.lastError: The message port closed before a response was received' chrome issue?

Make sure you are using the correct syntax.

We should use the sendMessage() method after listening it.

Here is a simple example of contentScript.js It sendRequest to app.js.

contentScript.js

chrome.extension.sendRequest({
    title: 'giveSomeTitle', params: paramsToSend
  }, function(result) { 
    // Do Some action
});

app.js

chrome.extension.onRequest.addListener( function(message, sender, 
 sendResponse) {
  if(message.title === 'giveSomeTitle'){
    // Do some action with message.params
    sendResponse(true);
  }
});

How to align entire html body to the center?

<style>
        body{
            max-width: 1180px;
            width: 98%;
            margin: 0px auto;
            text-align: left;
        }
</style>

Just apply this style before applying any CSS. You can change width as per your need.

Bash scripting missing ']'

add a space before the close bracket

How can I get two form fields side-by-side, with each field’s label above the field, in CSS?

How about something like this?

<div id="leftContainer">
  <span>Company Name</span>
  <br><input type="text" value="John Lewis Partnership">
</div>
<div id="rightContainer">
  <span>Contact Name</span>
  <br><input type="text" value="Timothy Patten">
</div>

Then, you can align the 2 divs by floating them left and right:-

#leftContainer {
   float:left;
}

#rightContainer {
   float:right;
}

uncaught syntaxerror unexpected token U JSON

This answer can be a possible solution from many. This answer is for the people who are facing this error while working with File Upload..

We were using middleware for token based encryption - decryption and we encountered same error.

Following was our code in route file:

  router.route("/uploadVideoMessage")
  .post(
    middleware.checkToken,
    upload.single("video_file"),
    videoMessageController.uploadVideoMessage
  );

here we were calling middleware before upload function and that was causing the error. So when we changed it to this, it worked.

router.route("/uploadVideoMessage")
  .post(
    upload.single("video_file"),
    middleware.checkToken,
    videoMessageController.uploadVideoMessage
  );

Increasing nesting function calls limit

Do you have Zend, IonCube, or xDebug installed? If so, that is probably where you are getting this error from.

I ran into this a few years ago, and it ended up being Zend putting that limit there, not PHP. Of course removing it will let you go past the 100 iterations, but you will eventually hit the memory limits.

How do I toggle an ng-show in AngularJS based on a boolean?

Here's an example to use ngclick & ng-if directives.

Note: that ng-if removes the element from the DOM, but ng-hide just hides the display of the element.

<!-- <input type="checkbox" ng-model="hideShow" ng-init="hideShow = false"></input> -->

<input type = "button" value = "Add Book"ng-click="hideShow=(hideShow ? false : true)"> </input>
     <div ng-app = "mainApp" ng-controller = "bookController" ng-if="hideShow">
             Enter book name: <input type = "text" ng-model = "book.name"><br>
             Enter book category: <input type = "text" ng-model = "book.category"><br>
             Enter book price: <input type = "text" ng-model = "book.price"><br>
             Enter book author: <input type = "text" ng-model = "book.author"><br>


             You are entering book: {{book.bookDetails()}}
     </div>

    <script>
             var mainApp = angular.module("mainApp", []);

             mainApp.controller('bookController', function($scope) {
                $scope.book = {
                   name: "",
                   category: "",
                   price:"",
                   author: "",


                   bookDetails: function() {
                      var bookObject;
                      bookObject = $scope.book;
                      return "Book name: " + bookObject.name +  '\n' + "Book category: " + bookObject.category + "  \n" + "Book price: " + bookObject.price + "  \n" + "Book Author: " + bookObject.author;
                   }

                };
             });
    </script>

How to sort alphabetically while ignoring case sensitive?

Collections.sort() lets you pass a custom comparator for ordering. For case insensitive ordering String class provides a static final comparator called CASE_INSENSITIVE_ORDER.

So in your case all that's needed is:

Collections.sort(caps, String.CASE_INSENSITIVE_ORDER);

What causes a SIGSEGV

There are various causes of segmentation faults, but fundamentally, you are accessing memory incorrectly. This could be caused by dereferencing a null pointer, or by trying to modify readonly memory, or by using a pointer to somewhere that is not mapped into the memory space of your process (that probably means you are trying to use a number as a pointer, or you incremented a pointer too far). On some machines, it is possible for a misaligned access via a pointer to cause the problem too - if you have an odd address and try to read an even number of bytes from it, for example (that can generate SIGBUS, instead).

How to return 2 values from a Java method?

Java does not support multi-value returns. Return an array of values.

// Function code
public static int[] something(){
    int number1 = 1;
    int number2 = 2;
    return new int[] {number1, number2};
}

// Main class code
public static void main(String[] args) {
  int result[] = something();
  System.out.println(result[0] + result[1]);
}

How can I start PostgreSQL server on Mac OS X?

Sometimes it's just the version which you are missing, and you are scratching your head unnecessarily.

If you are using a specific version of PostgreSQL, for example, PostgreSQL 10, then simply do

brew services start postgresql@10

brew services stop postgresql@10

The normal brew services start postgresql won't work without a version if you have installed it for a specific version from Homebrew.

How to add image in Flutter

I think the error is caused by the redundant ,

flutter:
  uses-material-design: true, # <<< redundant , at the end of the line
  assets:
    - images/lake.jpg

I'd also suggest to create an assets folder in the directory that contains the pubspec.yaml file and move images there and use

flutter:
  uses-material-design: true
  assets:
    - assets/images/lake.jpg

The assets directory will get some additional IDE support that you won't have if you put assets somewhere else.

Typescript: Type X is missing the following properties from type Y length, pop, push, concat, and 26 more. [2740]

For those newbies like me, don't assign variable to service response, meaning do

export class ShopComponent implements OnInit {
  public productsArray: Product[];

  ngOnInit() {
      this.productService.getProducts().subscribe(res => {
        this.productsArray = res;
      });
  }
}

Instead of

export class ShopComponent implements OnInit {
    public productsArray: Product[];

    ngOnInit() {
        this.productsArray = this.productService.getProducts().subscribe();
    }
}

How do I write a bash script to restart a process if it dies?

You should use monit, a standard unix tool that can monitor different things on the system and react accordingly.

From the docs: http://mmonit.com/monit/documentation/monit.html#pid_testing

check process checkqueue.py with pidfile /var/run/checkqueue.pid
       if changed pid then exec "checkqueue_restart.sh"

You can also configure monit to email you when it does do a restart.

How can I extract audio from video with ffmpeg?

The command line is correct and works on a valid video file. I would make sure that you have installed the correct library to work with mp3, install lame o probe with another audio codec.

Usually

ffmpeg -formats

or

ffmpeg -codecs

would give sufficient information so that you know more.

Is there Java HashMap equivalent in PHP?

HashMap that also works with keys other than strings and integers with O(1) read complexity (depending on quality of your own hash-function).

You can make a simple hashMap yourself. What a hashMap does is storing items in a array using the hash as index/key. Hash-functions give collisions once in a while (not often, but they may do), so you have to store multiple items for an entry in the hashMap. That simple is a hashMap:

class IEqualityComparer {
    public function equals($x, $y) {
        throw new Exception("Not implemented!");
    }
    public function getHashCode($obj) {
        throw new Exception("Not implemented!");
    }
}

class HashMap {
    private $map = array();
    private $comparer;

    public function __construct(IEqualityComparer $keyComparer) {
        $this->comparer = $keyComparer;
    }

    public function has($key) {
        $hash = $this->comparer->getHashCode($key);

        if (!isset($this->map[$hash])) {
            return false;
        }

        foreach ($this->map[$hash] as $item) {
            if ($this->comparer->equals($item['key'], $key)) {
                return true;
            }
        }

        return false;
    }

    public function get($key) {
        $hash = $this->comparer->getHashCode($key);

        if (!isset($this->map[$hash])) {
            return false;
        }

        foreach ($this->map[$hash] as $item) {
            if ($this->comparer->equals($item['key'], $key)) {
                return $item['value'];
            }
        }

        return false;
    }

    public function del($key) {
        $hash = $this->comparer->getHashCode($key);

        if (!isset($this->map[$hash])) {
            return false;
        }

        foreach ($this->map[$hash] as $index => $item) {
            if ($this->comparer->equals($item['key'], $key)) {
                unset($this->map[$hash][$index]);
                if (count($this->map[$hash]) == 0)
                    unset($this->map[$hash]);

                return true;
            }
        }

        return false;
    }

    public function put($key, $value) {
        $hash = $this->comparer->getHashCode($key);

        if (!isset($this->map[$hash])) {
            $this->map[$hash] = array();
        }

        $newItem = array('key' => $key, 'value' => $value);        

        foreach ($this->map[$hash] as $index => $item) {
            if ($this->comparer->equals($item['key'], $key)) {
                $this->map[$hash][$index] = $newItem;
                return;
            }
        }

        $this->map[$hash][] = $newItem;
    }
}

For it to function you also need a hash-function for your key and a comparer for equality (if you only have a few items or for another reason don't need speed you can let the hash-function return 0; all items will be put in same bucket and you will get O(N) complexity)

Here is an example:

class IntArrayComparer extends IEqualityComparer {
    public function equals($x, $y) {
        if (count($x) !== count($y))
            return false;

        foreach ($x as $key => $value) {
            if (!isset($y[$key]) || $y[$key] !== $value)
                return false;
        }

        return true;
    }

    public function getHashCode($obj) {
        $hash = 0;
        foreach ($obj as $key => $value)
            $hash ^= $key ^ $value;

        return $hash;
    }
}

$hashmap = new HashMap(new IntArrayComparer());

for ($i = 0; $i < 10; $i++) {
    for ($j = 0; $j < 10; $j++) {
        $hashmap->put(array($i, $j), $i * 10 + $j);
    }
}

echo $hashmap->get(array(3, 7)) . "<br/>";
echo $hashmap->get(array(5, 1)) . "<br/>";

echo ($hashmap->has(array(8, 4))? 'true': 'false') . "<br/>";
echo ($hashmap->has(array(-1, 9))? 'true': 'false') . "<br/>";
echo ($hashmap->has(array(6))? 'true': 'false') . "<br/>";
echo ($hashmap->has(array(1, 2, 3))? 'true': 'false') . "<br/>";

$hashmap->del(array(8, 4));
echo ($hashmap->has(array(8, 4))? 'true': 'false') . "<br/>";

Which gives as output:

37
51
true
false
false
false
false

Generating random integer from a range

I recommend the Boost.Random library, it's super detailed and well-documented, lets you explicitly specify what distribution you want, and in non-cryptographic scenarios can actually outperform a typical C library rand implementation.

How to Find App Pool Recycles in Event Log

As it seems impossible to filter the XPath message data (it isn't in the XML to filter), you can also use powershell to search:

Get-WinEvent -LogName System | Where-Object {$_.Message -like "*recycle*"}

From this, I can see that the event Id for recycling seems to be 5074, so you can filter on this as well. I hope this helps someone as this information seemed to take a lot longer than expected to work out.

This along with @BlackHawkDesign comment should help you find what you need.

I had the same issue. Maybe interesting to mention is that you have to configure in which cases the app pool recycle event is logged. By default it's in a couple of cases, not all of them. You can do that in IIS > app pools > select the app pool > advanced settings > expand generate recycle event log entry – BlackHawkDesign Jan 14 '15 at 10:00

Escape double quotes in Java

Yes you will have to escape all double quotes by a backslash.

How to globally replace a forward slash in a JavaScript string?

Use a regex literal with the g modifier, and escape the forward slash with a backslash so it doesn't clash with the delimiters.

var str = 'some // slashes', replacement = '';
var replaced = str.replace(/\//g, replacement);

How to add text at the end of each line in Vim?

Following Macro can also be used to accomplish your task.

qqA,^[0jq4@q

MySQL: can't access root account

There is a section in the MySQL manual on how to reset the root password which will solve your problem.

Installing ADB on macOS

Option 3 - Using MacPorts

Analoguously to the two options (homebrew / manual) posted by @brismuth, here's the MacPorts way:

  1. Install the Android SDK:

    sudo port install android
    
  2. Run the SDK manager:

    sh /opt/local/share/java/android-sdk-macosx/tools/android
    
  3. As @brismuth suggested, uncheck everything but Android SDK Platform-tools (optional)

  4. Install the packages, accepting licenses. Close the SDK Manager.

  5. Add platform-tools to your path; in MacPorts, they're in /opt/local/share/java/android-sdk-macosx/platform-tools. E.g., for bash:

    echo 'export PATH=$PATH:/opt/local/share/java/android-sdk-macosx/platform-tools' >> ~/.bash_profile
    
  6. Refresh your bash profile (or restart your terminal/shell):

    source ~/.bash_profile
    
  7. Start using adb:

    adb devices
    

sql how to cast a select query

If you're using SQL (which you didn't say):

select cast(column as varchar(200)) from table 

You can use it in any statement, for example:

select value where othervalue in( select cast(column as varchar(200)) from table)
from othertable

If you want to do a join query, the answer is here already in another post :)

How do I get the resource id of an image if I know its name?

With something like this:

String mDrawableName = "myappicon";
int resID = getResources().getIdentifier(mDrawableName , "drawable", getPackageName());