#Intense debate | Programs & Examples on Intense debate

How to make a whole 'div' clickable in html and css without JavaScript?

jQuery would allow you to do that.

Look up the click() function: http://api.jquery.com/click/

Example:

$('#yourDIV').click(function() {
  alert('You clicked the DIV.');
});

Jaxb, Class has two properties of the same name

Same problem I faced, I added

@XmlRootElement(name="yourRootElementName")

@XmlAccessorType(XmlAccessType.FIELD)

and now it is working.

Android: resizing imageview in XML

Mark,

I believe you want to use android:scaleType="fitXY".

XML Serialize generic list of serializable objects

If the XML output requirement can be changed you can always use binary serialization - which is better suited for working with heterogeneous lists of objects. Here's an example:

private void SerializeList(List<Object> Targets, string TargetPath)
{
    IFormatter Formatter = new BinaryFormatter();

    using (FileStream OutputStream = System.IO.File.Create(TargetPath))
    {
        try
        {
            Formatter.Serialize(OutputStream, Targets);
        } catch (SerializationException ex) {
            //(Likely Failed to Mark Type as Serializable)
            //...
        }
}

Use as such:

[Serializable]
public class Animal
{
    public string Home { get; set; }
}

[Serializable]
public class Person
{
    public string Name { get; set; }
}


public void ExampleUsage() {

    List<Object> SerializeMeBaby = new List<Object> {
        new Animal { Home = "London, UK" },
        new Person { Name = "Skittles" }
    };

    string TargetPath = Path.Combine(
        Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
        "Test1.dat");

    SerializeList(SerializeMeBaby, TargetPath);
}

How can I know if a branch has been already merged into master?

You can use the git merge-base command to find the latest common commit between the two branches. If that commit is the same as your branch head, then the branch has been completely merged.

Note that git branch -d does this sort of thing already because it will refuse to delete a branch that hasn't already been completely merged.

Asynchronously load images with jQuery

If you just want to set the source of the image you can use this.

$("img").attr('src','http://somedomain.com/image.jpg');

How to make child divs always fit inside parent div?

I think I have the solution to your question, assuming you can use flexbox in your project. What you want to do is make #one a flexbox using display: flex and use flex-direction: column to make it a column alignment.

_x000D_

html,_x000D_
body {_x000D_
  width: 100%;_x000D_
  height: 100%;_x000D_
  margin: 0;_x000D_
  padding: 0;_x000D_
}_x000D_
_x000D_
.border {_x000D_
  border: 1px solid black;_x000D_
}_x000D_
_x000D_
.margin {_x000D_
  margin: 5px;_x000D_
}_x000D_
_x000D_
#one {_x000D_
  width: 100%;_x000D_
  height: 100%;_x000D_
  display: flex;_x000D_
  flex-direction: column;_x000D_
}_x000D_
_x000D_
#two {_x000D_
  height: 50px;_x000D_
}_x000D_
_x000D_
#three {_x000D_
  width: 100px;_x000D_
  height: 100%;_x000D_
}

_x000D_

<html>_x000D_
_x000D_
<head>_x000D_
</head>_x000D_
_x000D_
<body>_x000D_
  <div id="one" class="border">_x000D_
    <div id="two" class="border margin"></div>_x000D_
    <div id="three" class="border margin"></div>_x000D_
  </div>_x000D_
</body>_x000D_
_x000D_
</html>

_x000D_

How can I capture the result of var_dump to a string?

Use output buffering:

<?php
ob_start();
var_dump($someVar);
$result = ob_get_clean();
?>

What Content-Type value should I send for my XML sitemap?

text/xml is for documents that would be meaningful to a human if presented as text without further processing, application/xml is for everything else

Every XML entity is suitable for use with the application/xml media type without modification. But this does not exploit the fact that XML can be treated as plain text in many cases. MIME user agents (and web user agents) that do not have explicit support for application/xml will treat it as application/octet-stream, for example, by offering to save it to a file.

To indicate that an XML entity should be treated as plain text by default, use the text/xml media type. This restricts the encoding used in the XML entity to those that are compatible with the requirements for text media types as described in [RFC-2045] and [RFC-2046], e.g., UTF-8, but not UTF-16 (except for HTTP).

— http://www.ietf.org/rfc/rfc2376.txt

"Parser Error Message: Could not load type" in Global.asax

I closed and reopened visual studio and it worked.

Get current time as formatted string in Go?

As an echo to @Bactisme's response, the way one would go about retrieving the current timestamp (in milliseconds, for example) is:

msec := time.Now().UnixNano() / 1000000

Resource: https://gobyexample.com/epoch

How to save the contents of a div as a image?

Do something like this:

A <div> with ID of #imageDIV, another one with ID #download and a hidden <div> with ID #previewImage.

Include the latest version of jquery, and jspdf.debug.js from the jspdf CDN

Then add this script:

var element = $("#imageDIV"); // global variable
var getCanvas; // global variable
$('document').ready(function(){
  html2canvas(element, {
    onrendered: function (canvas) {
      $("#previewImage").append(canvas);
      getCanvas = canvas;
    }
  });
});
$("#download").on('click', function () {
  var imgageData = getCanvas.toDataURL("image/png");
  // Now browser starts downloading it instead of just showing it
  var newData = imageData.replace(/^data:image\/png/, "data:application/octet-stream");
  $("#download").attr("download", "image.png").attr("href", newData);
});

The div will be saved as a PNG on clicking the #download

List Highest Correlation Pairs from a Large Correlation Matrix in Pandas?

Combining some features of @HYRY and @arun's answers, you can print the top correlations for dataframe df in a single line using:

df.corr().unstack().sort_values().drop_duplicates()

Note: the one downside is if you have 1.0 correlations that are not one variable to itself, the drop_duplicates() addition would remove them

internet explorer 10 - how to apply grayscale filter?

IE10 does not support DX filters as IE9 and earlier have done, nor does it support a prefixed version of the greyscale filter.

However, you can use an SVG overlay in IE10 to accomplish the greyscaling. Example:

img.grayscale:hover {
    filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'1 0 0 0 0, 0 1 0 0 0, 0 0 1 0 0, 0 0 0 1 0\'/></filter></svg>#grayscale");
}

svg {
    background:url(http://4.bp.blogspot.com/-IzPWLqY4gJ0/T01CPzNb1KI/AAAAAAAACgA/_8uyj68QhFE/s400/a2cf7051-5952-4b39-aca3-4481976cb242.jpg);
}

(from: http://www.karlhorky.com/2012/06/cross-browser-image-grayscale-with-css.html)

Simplified JSFiddle: http://jsfiddle.net/KatieK/qhU7d/2/

More about the IE10 SVG filter effects: http://blogs.msdn.com/b/ie/archive/2011/10/14/svg-filter-effects-in-ie10.aspx

Show/hide image with JavaScript

HTML

<img id="theImage" src="yourImage.png">
<a id="showImage">Show image</a>

JavaScript:

document.getElementById("showImage").onclick = function() {
    document.getElementById("theImage").style.display = "block";
}

CSS:

#theImage { display:none; }

How to square all the values in a vector in R?

How about sapply (not really necessary for this simple case):

newData<- sapply(data, function(x) x^2)

Regular expression to match numbers with or without commas and decimals in text

(,*[\d]+,*[\d]*)+

This would match any small or large number as following with or without comma

1
100
1,262
1,56,262
10,78,999
12,34,56,789

Simpler way to create dictionary of separate variables?

With python 2.7 and newer there is also dictionary comprehension which makes it a bit shorter. If possible I would use getattr instead eval (eval is evil) like in the top answer. Self can be any object which has the context your a looking at. It can be an object or locals=locals() etc.

{name: getattr(self, name) for name in ['some', 'vars', 'here]}

How to resolve : Can not find the tag library descriptor for "http://java.sun.com/jsp/jstl/core"

I solved this issue. use below taglib

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

and add jstl-1.2.jar

Could not autowire field in spring. why?

When you get this error some annotation is missing. I was missing @service annotation on service. When I added that annotation it worked fine for me.

Convert blob URL to normal URL

As the previous answer have said, there is no way to decode it back to url, even when you try to see it from the chrome devtools panel, the url may be still encoded as blob.

However, it's possible to get the data, another way to obtain the data is to put it into an anchor and directly download it.

<a href="blob:http://example.com/xxxx-xxxx-xxxx-xxxx" download>download</a>

Insert this to the page containing blob url and click the button, you get the content.

Another way is to intercept the ajax call via a proxy server, then you could view the true image url.

How do I allow HTTPS for Apache on localhost?

This worked on Windows 10 with Apache24:

1 - Add this at the bottom of C:/Apache24/conf/httpd.conf

Listen 443
<VirtualHost *:443>
    DocumentRoot "C:/Apache24/htdocs"
    ServerName localhost
    SSLEngine on
    SSLCertificateFile "C:/Apache24/conf/ssl/server.crt"
    SSLCertificateKeyFile "C:/Apache24/conf/ssl/server.key"
</VirtualHost>

2 - Add the server.crt and server.key files in the C:/Apache24/conf/ssl folder. See other answers on this page to find those 2 files.

That's it!

mySQL convert varchar to date

select date_format(str_to_date('31/12/2010', '%d/%m/%Y'), '%Y%m');

select date_format(str_to_date('12/31/2011', '%m/%d/%Y'), '%Y%m');

hard to tell from your example

How to pass all arguments passed to my bash script to a function of mine?

Use the $@ variable, which expands to all command-line parameters separated by spaces.

abc "$@"

django MultiValueDictKeyError error, how do I deal with it

First check if the request object have the 'is_private' key parameter. Most of the case's this MultiValueDictKeyError occurred for missing key in the dictionary-like request object. Because dictionary is an unordered key, value pair “associative memories” or “associative arrays”

In another word. request.GET or request.POST is a dictionary-like object containing all request parameters. This is specific to Django.

The method get() returns a value for the given key if key is in the dictionary. If key is not available then returns default value None.

You can handle this error by putting :

is_private = request.POST.get('is_private', False);

Javascript Image Resize

Use JQuery

var scale=0.5;

minWidth=50;
minHeight=100;

if($("#id img").width()*scale>minWidth && $("#id img").height()*scale >minHeight)
{
    $("#id img").width($("#id img").width()*scale);
    $("#id img").height($("#id img").height()*scale);
}

What is the difference between SQL, PL-SQL and T-SQL?

Structured Query Language - SQL: is an ANSI-standard used by almost all SGBD's vendors around the world. Basically, SQL is a language used to define and manipulate data [DDL and DML].

PL/SQL is a language created by Oracle universe. PL/SQL combine programming procedural instructions and allows the creation of programs that operates directly on database scenario.

T-SQL is Microsoft product align SQL patterns, with some peculiarities. So, feel free to test your limits.

Is there a way to pass javascript variables in url?

Do you mean include javascript variable values in the query string of the URL?

Yes:

 window.location.href = "http://www.gorissen.info/Pierre/maps/googleMapLocation.php?lat="+var1+"&lon="+var2+"&setLatLon="+varEtc;

How can I run specific migration in laravel

use this command php artisan migrate --path=/database/migrations/my_migration.php it worked for me..

GROUP BY with MAX(DATE)

Another solution:

select * from traintable
where (train, time) in (select train, max(time) from traintable group by train);

How to split a string in Ruby and get all items except the first one?

Try this:

first, *rest = ex.split(/, /)

Now first will be the first value, rest will be the rest of the array.

Warning: date_format() expects parameter 1 to be DateTime

Best way is use DateTime object to convert your date.

$myDateTime = DateTime::createFromFormat('Y-m-d', $weddingdate);
$formattedweddingdate = $myDateTime->format('d-m-Y');

Note: It will support for PHP 5 >= 5.3.0 only.

how to create Socket connection in Android?

Simple socket server app example

I've already posted a client example at: https://stackoverflow.com/a/35971718/895245 , so here goes a server example.

This example app runs a server that returns a ROT-1 cypher of the input.

You would then need to add an Exit button + some sleep delays, but this should get you started.

To play with it:

install the app
get your phone and PC on a LAN
find your phone's IP with https://android.stackexchange.com/a/130468/126934
run netcat $PHONE_IP 12345
type some lines

Android sockets are the same as Java's, except we have to deal with some permission issues.

src/com/cirosantilli/android_cheat/socket/Main.java

package com.cirosantilli.android_cheat.socket;

import android.app.Activity;
import android.app.IntentService;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.ServerSocket;
import java.net.Socket;

public class Main extends Activity {
    static final String TAG = "AndroidCheatSocket";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Log.d(Main.TAG, "onCreate");
        Main.this.startService(new Intent(Main.this, MyService.class));
    }

    public static class MyService extends IntentService {
        public MyService() {
            super("MyService");
        }
        @Override
        protected void onHandleIntent(Intent intent) {
            Log.d(Main.TAG, "onHandleIntent");
            final int port = 12345;
            ServerSocket listener = null;
            try {
                listener = new ServerSocket(port);
                Log.d(Main.TAG, String.format("listening on port = %d", port));
                while (true) {
                    Log.d(Main.TAG, "waiting for client");
                    Socket socket = listener.accept();
                    Log.d(Main.TAG, String.format("client connected from: %s", socket.getRemoteSocketAddress().toString()));
                    BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                    PrintStream out = new PrintStream(socket.getOutputStream());
                    for (String inputLine; (inputLine = in.readLine()) != null;) {
                        Log.d(Main.TAG, "received");
                        Log.d(Main.TAG, inputLine);
                        StringBuilder outputStringBuilder = new StringBuilder("");
                        char inputLineChars[] = inputLine.toCharArray();
                        for (char c : inputLineChars)
                            outputStringBuilder.append(Character.toChars(c + 1));
                        out.println(outputStringBuilder);
                    }
                }
            } catch(IOException e) {
                Log.d(Main.TAG, e.toString());
            }
        }
    }
}

We need a Service or other background method or else: How do I fix android.os.NetworkOnMainThreadException?

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.cirosantilli.android_cheat.socket"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="22" />
    <uses-permission android:name="android.permission.INTERNET" />
    <application android:label="AndroidCheatsocket">
        <activity android:name="Main">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <service android:name=".Main$MyService" />
    </application>
</manifest>

We must add: <uses-permission android:name="android.permission.INTERNET" /> or else: Java socket IOException - permission denied

On GitHub with a build.xml: https://github.com/cirosantilli/android-cheat/tree/92de020d0b708549a444ebd9f881de7b240b3fbc/socket

Python: avoid new line with print command

You simply need to do:

print 'lakjdfljsdf', # trailing comma

However in:

print 'lkajdlfjasd', 'ljkadfljasf'

There is implicit whitespace (ie ' ').

You also have the option of:

import sys
sys.stdout.write('some data here without a new line')

Setting up MySQL and importing dump within Dockerfile

Each RUN instruction in a Dockerfile is executed in a different layer (as explained in the documentation of RUN).

In your Dockerfile, you have three RUN instructions. The problem is that MySQL server is only started in the first. In the others, no MySQL are running, that is why you get your connection error with mysql client.

To solve this problem you have 2 solutions.

Solution 1: use a one-line `RUN`

RUN /bin/bash -c "/usr/bin/mysqld_safe --skip-grant-tables &" && \
  sleep 5 && \
  mysql -u root -e "CREATE DATABASE mydb" && \
  mysql -u root mydb < /tmp/dump.sql

Solution 2: use a script

Create an executable script init_db.sh:

#!/bin/bash
/usr/bin/mysqld_safe --skip-grant-tables &
sleep 5
mysql -u root -e "CREATE DATABASE mydb"
mysql -u root mydb < /tmp/dump.sql

Add these lines to your Dockerfile:

ADD init_db.sh /tmp/init_db.sh
RUN /tmp/init_db.sh

Git On Custom SSH Port

(Update: a few years later Google and Qwant "airlines" still send me here when searching for "git non-default ssh port") A probably better way in newer git versions is to use the GIT_SSH_COMMAND ENV.VAR like:

GIT_SSH_COMMAND="ssh -oPort=1234 -i ~/.ssh/myPrivate_rsa.key" \ git clone myuser@myGitRemoteServer:/my/remote/git_repo/path

This has the added advantage of allowing any other ssh suitable option (port, priv.key, IPv6, PKCS#11 device, ...).

MySql: is it possible to 'SUM IF' or to 'COUNT IF'?

It is worth noting that you can build upon Gavin Toweys answer by using multiple fields from across your query such as

SUM(table.field = 1 AND table2.field = 2)

You can also use this syntax for COUNT and I am sure other functions as well.

How to get a variable value if variable name is stored as string?

X=foo
Y=X
eval "Z=\$$Y"

sets Z to "foo"

Take care using eval since this may allow accidential excution of code through values in ${Y}. This may cause harm through code injection.

For example

Y="\`touch /tmp/eval-is-evil\`"

would create /tmp/eval-is-evil. This could also be some rm -rf /, of course.

How do I parse a string to a float or int?

float("545.2222") and int(float("545.2222"))

C++ wait for user input

Several ways to do so, here are some possible one-line approaches:

Use getch() (need #include <conio.h>).
Use getchar() (expected for Enter, need #include <iostream>).
Use cin.get() (expected for Enter, need #include <iostream>).
Use system("pause") (need #include <iostream>).

PS: This method will also print Press any key to continue . . . on the screen. (seems perfect choice for you :))

Edit: As discussed here, There is no completely portable solution for this. Question 19.1 of the comp.lang.c FAQ covers this in some depth, with solutions for Windows, Unix-like systems, and even MS-DOS and VMS.

Which method performs better: .Any() vs .Count() > 0?

Note: I wrote this answer when Entity Framework 4 was actual. The point of this answer was not to get into trivial .Any() vs .Count() performance testing. The point was to signal that EF is far from perfect. Newer versions are better... but if you have part of code that's slow and it uses EF, test with direct TSQL and compare performance rather than relying on assumptions (that .Any() is ALWAYS faster than .Count() > 0).

While I agree with most up-voted answer and comments - especially on the point Any signals developer intent better than Count() > 0 - I've had situation in which Count is faster by order of magnitude on SQL Server (EntityFramework 4).

Here is query with Any that thew timeout exception (on ~200.000 records):

con = db.Contacts.
    Where(a => a.CompanyId == companyId && a.ContactStatusId <= (int) Const.ContactStatusEnum.Reactivated
        && !a.NewsletterLogs.Any(b => b.NewsletterLogTypeId == (int) Const.NewsletterLogTypeEnum.Unsubscr)
    ).OrderBy(a => a.ContactId).
    Skip(position - 1).
    Take(1).FirstOrDefault();

Count version executed in matter of milliseconds:

con = db.Contacts.
    Where(a => a.CompanyId == companyId && a.ContactStatusId <= (int) Const.ContactStatusEnum.Reactivated
        && a.NewsletterLogs.Count(b => b.NewsletterLogTypeId == (int) Const.NewsletterLogTypeEnum.Unsubscr) == 0
    ).OrderBy(a => a.ContactId).
    Skip(position - 1).
    Take(1).FirstOrDefault();

I need to find a way to see what exact SQL both LINQs produce - but it's obvious there is a huge performance difference between Count and Any in some cases, and unfortunately it seems you can't just stick with Any in all cases.

EDIT: Here are generated SQLs. Beauties as you can see ;)

ANY:

exec sp_executesql N'SELECT TOP (1) 
[Project2].[ContactId] AS [ContactId], 
[Project2].[CompanyId] AS [CompanyId], 
[Project2].[ContactName] AS [ContactName], 
[Project2].[FullName] AS [FullName], 
[Project2].[ContactStatusId] AS [ContactStatusId], 
[Project2].[Created] AS [Created]
FROM ( SELECT [Project2].[ContactId] AS [ContactId], [Project2].[CompanyId] AS [CompanyId], [Project2].[ContactName] AS [ContactName], [Project2].[FullName] AS [FullName], [Project2].[ContactStatusId] AS [ContactStatusId], [Project2].[Created] AS [Created], row_number() OVER (ORDER BY [Project2].[ContactId] ASC) AS [row_number]
    FROM ( SELECT 
        [Extent1].[ContactId] AS [ContactId], 
        [Extent1].[CompanyId] AS [CompanyId], 
        [Extent1].[ContactName] AS [ContactName], 
        [Extent1].[FullName] AS [FullName], 
        [Extent1].[ContactStatusId] AS [ContactStatusId], 
        [Extent1].[Created] AS [Created]
        FROM [dbo].[Contact] AS [Extent1]
        WHERE ([Extent1].[CompanyId] = @p__linq__0) AND ([Extent1].[ContactStatusId] <= 3) AND ( NOT EXISTS (SELECT 
            1 AS [C1]
            FROM [dbo].[NewsletterLog] AS [Extent2]
            WHERE ([Extent1].[ContactId] = [Extent2].[ContactId]) AND (6 = [Extent2].[NewsletterLogTypeId])
        ))
    )  AS [Project2]
)  AS [Project2]
WHERE [Project2].[row_number] > 99
ORDER BY [Project2].[ContactId] ASC',N'@p__linq__0 int',@p__linq__0=4

COUNT:

exec sp_executesql N'SELECT TOP (1) 
[Project2].[ContactId] AS [ContactId], 
[Project2].[CompanyId] AS [CompanyId], 
[Project2].[ContactName] AS [ContactName], 
[Project2].[FullName] AS [FullName], 
[Project2].[ContactStatusId] AS [ContactStatusId], 
[Project2].[Created] AS [Created]
FROM ( SELECT [Project2].[ContactId] AS [ContactId], [Project2].[CompanyId] AS [CompanyId], [Project2].[ContactName] AS [ContactName], [Project2].[FullName] AS [FullName], [Project2].[ContactStatusId] AS [ContactStatusId], [Project2].[Created] AS [Created], row_number() OVER (ORDER BY [Project2].[ContactId] ASC) AS [row_number]
    FROM ( SELECT 
        [Project1].[ContactId] AS [ContactId], 
        [Project1].[CompanyId] AS [CompanyId], 
        [Project1].[ContactName] AS [ContactName], 
        [Project1].[FullName] AS [FullName], 
        [Project1].[ContactStatusId] AS [ContactStatusId], 
        [Project1].[Created] AS [Created]
        FROM ( SELECT 
            [Extent1].[ContactId] AS [ContactId], 
            [Extent1].[CompanyId] AS [CompanyId], 
            [Extent1].[ContactName] AS [ContactName], 
            [Extent1].[FullName] AS [FullName], 
            [Extent1].[ContactStatusId] AS [ContactStatusId], 
            [Extent1].[Created] AS [Created], 
            (SELECT 
                COUNT(1) AS [A1]
                FROM [dbo].[NewsletterLog] AS [Extent2]
                WHERE ([Extent1].[ContactId] = [Extent2].[ContactId]) AND (6 = [Extent2].[NewsletterLogTypeId])) AS [C1]
            FROM [dbo].[Contact] AS [Extent1]
        )  AS [Project1]
        WHERE ([Project1].[CompanyId] = @p__linq__0) AND ([Project1].[ContactStatusId] <= 3) AND (0 = [Project1].[C1])
    )  AS [Project2]
)  AS [Project2]
WHERE [Project2].[row_number] > 99
ORDER BY [Project2].[ContactId] ASC',N'@p__linq__0 int',@p__linq__0=4

Seems that pure Where with EXISTS works much worse than calculating Count and then doing Where with Count == 0.

Let me know if you guys see some error in my findings. What can be taken out of all this regardless of Any vs Count discussion is that any more complex LINQ is way better off when rewritten as Stored Procedure ;).

Case-insensitive string comparison in C++

If you are on a POSIX system, you can use strcasecmp. This function is not part of standard C, though, nor is it available on Windows. This will perform a case-insensitive comparison on 8-bit chars, so long as the locale is POSIX. If the locale is not POSIX, the results are undefined (so it might do a localized compare, or it might not). A wide-character equivalent is not available.

Failing that, a large number of historic C library implementations have the functions stricmp() and strnicmp(). Visual C++ on Windows renamed all of these by prefixing them with an underscore because they aren’t part of the ANSI standard, so on that system they’re called _stricmp or _strnicmp. Some libraries may also have wide-character or multibyte equivalent functions (typically named e.g. wcsicmp, mbcsicmp and so on).

C and C++ are both largely ignorant of internationalization issues, so there's no good solution to this problem, except to use a third-party library. Check out IBM ICU (International Components for Unicode) if you need a robust library for C/C++. ICU is for both Windows and Unix systems.

How to add title to seaborn boxplot

Try adding this at the end of your code:

import matplotlib.pyplot as plt

plt.title('add title here')

How to make a promise from setTimeout

This is not an answer to the original question. But, as an original question is not a real-world problem it should not be a problem. I tried to explain to a friend what are promises in JavaScript and the difference between promise and callback.

Code below serves as an explanation:

//very basic callback example using setTimeout
//function a is asynchronous function
//function b used as a callback
function a (callback){
    setTimeout (function(){
       console.log ('using callback:'); 
       let mockResponseData = '{"data": "something for callback"}'; 
       if (callback){
          callback (mockResponseData);
       }
    }, 2000);

} 

function b (dataJson) {
   let dataObject = JSON.parse (dataJson);
   console.log (dataObject.data);   
}

a (b);

//rewriting above code using Promise
//function c is asynchronous function
function c () {
   return new Promise(function (resolve, reject) {
     setTimeout (function(){
       console.log ('using promise:'); 
       let mockResponseData = '{"data": "something for promise"}'; 
       resolve(mockResponseData); 
    }, 2000);      
   }); 

}

c().then (b);

JsFiddle

Why do you need to put #!/bin/bash at the beginning of a script file?

It's a convention so the *nix shell knows what kind of interpreter to run.

For example, older flavors of ATT defaulted to sh (the Bourne shell), while older versions of BSD defaulted to csh (the C shell).

Even today (where most systems run bash, the "Bourne Again Shell"), scripts can be in bash, python, perl, ruby, PHP, etc, etc. For example, you might see #!/bin/perl or #!/bin/perl5.

PS: The exclamation mark (!) is affectionately called "bang". The shell comment symbol (#) is sometimes called "hash".

PPS: Remember - under *nix, associating a suffix with a file type is merely a convention, not a "rule". An executable can be a binary program, any one of a million script types and other things as well. Hence the need for #!/bin/bash.

No connection could be made because the target machine actively refused it?

In my case this was caused by a faulty deployment where a setting in my web.config was not made.

A collegue explained that the IP address in the error message represents the localhost.

When I corrected the web.config I was then using the correct url to make the server calls and it worked.

I thought I would post this in case it might help someone.

Default keystore file does not exist?

Use This for MAC users

keytool -list -v -keystore ~/.android/debug.keystore -alias androiddebugkey -storepass android -keypass android

Getting one value from a tuple

You can write

i = 5 + tup()[0]

Tuples can be indexed just like lists.

The main difference between tuples and lists is that tuples are immutable - you can't set the elements of a tuple to different values, or add or remove elements like you can from a list. But other than that, in most situations, they work pretty much the same.

Adding elements to object

cart.push({"element":{ id: id, quantity: quantity }});

Importing Excel into a DataTable Quickly

MS Office Interop is slow and even Microsoft does not recommend Interop usage on server side and cannot be use to import large Excel files. For more details see why not to use OLE Automation from Microsoft point of view.

Instead, you can use any Excel library, like EasyXLS for example. This is a code sample that shows how to read the Excel file:

ExcelDocument workbook = new ExcelDocument();
DataSet ds = workbook.easy_ReadXLSActiveSheet_AsDataSet("excel.xls");
DataTable dataTable = ds.Tables[0];

If your Excel file has multiple sheets or for importing only ranges of cells (for better performances) take a look to more code samples on how to import Excel to DataTable in C# using EasyXLS.

Leaflet changing Marker color

Write a function which, given a color (or any other characteristics), returns an SVG representation of the desired icon. Then, when creating the marker, reference this function with the appropriate parameter(s).

How can multiple rows be concatenated into one in Oracle without creating a stored procedure?

Easy:

SELECT question_id, wm_concat(element_id) as elements
FROM   questions
GROUP BY question_id;

Pesonally tested on 10g ;-)

From http://www.oracle-base.com/articles/10g/StringAggregationTechniques.php

How to update column value in laravel

I tried to update a field with

$table->update(['field' => 'val']);

But it wasn't working, i had to modify my table Model to authorize this field to be edited : add 'field' in the array "protected $fillable"

Hope it will help someone :)

Can I change the height of an image in CSS :before/:after pseudo-elements?

You should use background instead of image.

.pdflink:after {
  content: "";
  background-image:url(your-image-url.png);
  background-size: 100% 100%;
  display: inline-block;

  /*size of your image*/
  height: 25px;
  width:25px;

  /*if you want to change the position you can use margins or:*/
  position:relative;
  top:5px;

}

Using ng-if as a switch inside ng-repeat?

Try to surround strings (hoot, story, article) with quotes ':

<div ng-repeat = "data in comments">
    <div ng-if="data.type == 'hoot' ">
        //different template with hoot data
    </div>
    <div ng-if="data.type == 'story' ">
        //different template with story data
    </div>
    <div ng-if="data.type == 'article' ">
        //different template with article data
    </div> 
</div>

DateTime format to SQL format using C#

Your problem is in the Date property that truncates DateTime to date only. You could put the conversion like this:

DateTime myDateTime = DateTime.Now;

string sqlFormattedDate = myDateTime.ToString("yyyy-MM-dd HH:mm:ss");

VirtualBox: mount.vboxsf: mounting failed with the error: No such device

If you're on Debian:

1) remove all installed package through Virtualbox Guest Additions ISO file:

sh /media/cdrom/VBoxLinuxAdditions.run uninstall

2) install Virtualbox packages:

apt-get install build-essential module-assistant virtualbox-guest-dkms virtualbox-guest-utils

Note that even with modprobe vboxsf returning nothing (so the module is correctly loaded), the vboxsf.so will call an executable named mount.vboxsf, which is provided by virtualbox-guest-utils. Ignoring this one will prevent you from understanding the real cause of the error.

strace mount /your-directory was a great help (No such file or directory on /sbin/mount.vboxsf).

Chrome - ERR_CACHE_MISS

This is a known issue in Chrome and resolved in latest versions. Please refer https://bugs.chromium.org/p/chromium/issues/detail?id=942440 for more details.

How might I force a floating DIV to match the height of another floating DIV?

I recommend you wrap them both in an outer div with the desired background color.

How to write a simple Html.DropDownListFor()?

@using (Html.BeginForm()) {
    <p>Do you like pizza?
        @Html.DropDownListFor(x => x.likesPizza, new[] {
            new SelectListItem() {Text = "Yes", Value = bool.TrueString},
            new SelectListItem() {Text = "No", Value = bool.FalseString}
        }, "Choose an option") 
    </p>
    <input type = "submit" value = "Submit my answer" />
}

I think this answer is similar to Berat's, in that you put all the code for your DropDownList directly in the view. But I think this is an efficient way of creating a y/n (boolean) drop down list, so I wanted to share it.

Some notes for beginners:

Don't worry about what 'x' is called - it is created here, for the first time, and doesn't link to anything else anywhere else in the MVC app, so you can call it what you want - 'x', 'model', 'm' etc.
The placeholder that users will see in the dropdown list is "Choose an option", so you can change this if you want.
There's a bit of text preceding the drop down which says "Do you like pizza?"
This should be complete text for a form, including a submit button, I think

Hope this helps someone,

Folder structure for a Node.js project

More example from my project architecture you can see here:

+-- Dockerfile
+-- README.md
+-- config
¦   +-- production.json
+-- package.json
+-- schema
¦   +-- create-db.sh
¦   +-- db.sql
+-- scripts
¦   +-- deploy-production.sh 
+-- src
¦   +-- app -> Containes API routes
¦   +-- db -> DB Models (ORM)
¦   +-- server.js -> the Server initlializer.
+-- test

Basically, the logical app separated to DB and APP folders inside the SRC dir.

SELECT using 'CASE' in SQL

This is just the syntax of the case statement, it looks like this.

SELECT 
  CASE 
    WHEN FRUIT = 'A' THEN 'APPLE' 
    WHEN FRUIT = 'B' THEN 'BANANA'     
  END AS FRUIT
FROM FRUIT_TABLE;

As a reminder remember; no assignment is performed the value becomes the column contents. (If you wanted to assign that to a variable you would put it before the CASE statement).

Can't escape the backslash with regex?

If you're putting this in a string within a program, you may actually need to use four backslashes (because the string parser will remove two of them when "de-escaping" it for the string, and then the regex needs two for an escaped regex backslash).

For instance:

regex("\\\\")

is interpreted as...

regex("\\" [escaped backslash] followed by "\\" [escaped backslash])

is interpreted as...

regex(\\)

is interpreted as a regex that matches a single backslash.

Depending on the language, you might be able to use a different form of quoting that doesn't parse escape sequences to avoid having to use as many - for instance, in Python:

re.compile(r'\\')

The r in front of the quotes makes it a raw string which doesn't parse backslash escapes.

Constants in Kotlin -- what's a recommended way to create them?

If you put your const val valName = valValue before the class name, this way it will creates a

public static final YourClass.Kt that will have the public static final values.

Kotlin:

const val MY_CONST0 = 0
const val MY_CONST1 = 1
data class MyClass(var some: String)

Java decompiled:

public final class MyClassKt {
    public static final int MY_CONST0 = 0;
    public static final int MY_CONST1 = 1;
}
// rest of MyClass.java

jquery variable syntax

This is pure JavaScript.

There is nothing special about $. It is just a character that may be used in variable names.

var $ = 1;
var $$ = 2;
alert($ + $$);

jQuery just assigns it's core function to a variable called $. The code you have assigns this to a local variable called self and the results of calling jQuery with this as an argument to a global variable called $self.

It's ugly, dirty, confusing, but $, self and $self are all different variables that happen to have similar names.

Testing pointers for validity (C/C++)

Setting the pointer to NULL before and after using is a good technique. This is easy to do in C++ if you manage pointers within a class for example (a string):

class SomeClass
{
public:
    SomeClass();
    ~SomeClass();

    void SetText( const char *text);
    char *GetText() const { return MyText; }
    void Clear();

private:
    char * MyText;
};


SomeClass::SomeClass()
{
    MyText = NULL;
}


SomeClass::~SomeClass()
{
    Clear();
}

void SomeClass::Clear()
{
    if (MyText)
        free( MyText);

    MyText = NULL;
}



void SomeClass::Settext( const char *text)
{
    Clear();

    MyText = malloc( strlen(text));

    if (MyText)
        strcpy( MyText, text);
}

How to convert a Java String to an ASCII byte array?

Using the getBytes method, giving it the appropriate Charset (or Charset name).

Example:

String s = "Hello, there.";
byte[] b = s.getBytes(StandardCharsets.US_ASCII);

(Before Java 7: byte[] b = s.getBytes("US-ASCII");)

IntelliJ does not show 'Class' when we right click and select 'New'

This can also happen if your package name is invalid.

For example, if your "package" is com.my-company (which is not a valid Java package name due to the dash), IntelliJ will prevent you from creating a Java Class in that package.

Best way to "push" into C# array

The is no array.push(newValue) in C#. You don't push to an Array in C#. What we use for this is a List<T>. What you may want to consider (for teaching purpose only) is the ArrayList (no generic and it is a IList, so ...).

static void Main()
{
    // Create an ArrayList and add 3 elements.
    ArrayList list = new ArrayList();
    list.Add("One"); // Add is your push
    list.Add("Two");
    list.Add("Three");
}

"unadd" a file to svn before commit

For Files - svn revert filename

For Folders - svn revert -R folder

How to construct a REST API that takes an array of id's for the resources

As much as I prefer this approach:-

    api.com/users?id=id1,id2,id3,id4,id5

The correct way is

    api.com/users?ids[]=id1&ids[]=id2&ids[]=id3&ids[]=id4&ids[]=id5

    api.com/users?ids=id1&ids=id2&ids=id3&ids=id4&ids=id5

This is how rack does it. This is how php does it. This is how node does it as well...

UNC path to a folder on my local computer

If you're going to access your local computer (or any computer) using UNC, you'll need to setup a share. If you haven't already setup a share, you could use the default administrative shares. Example:

\\localhost\c$\my_dir

... accesses a folder called "my_dir" via UNC on your C: drive. By default all the hard drives on your machine are shared with hidden shares like c$, d$, etc.

In excel how do I reference the current row but a specific column?

To static either a row or a column, put a $ sign in front of it. So if you were to use the formula =AVERAGE($A1,$C1) and drag it down the entire sheet, A and C would remain static while the 1 would change to the current row

If you're on Windows, you can achieve the same thing by repeatedly pressing F4 while in the formula editing bar. The first F4 press will static both (it will turn A1 into $A$1), then just the row (A$1) then just the column ($A1)

Although technically with the formulas that you have, dragging down for the entirety of the column shouldn't be a problem without putting a $ sign in front of the column. Setting the column as static would only come into play if you're dragging ACROSS columns and want to keep using the same column, and setting the row as static would be for dragging down rows but wanting to use the same row.

How to disable and then enable onclick event on <div> with javascript

You can disable the event by applying following code:

with .attr() API

$('#your_id').attr("disabled", "disabled");

or with .prop() API

$('#your_id').prop('disabled', true);

How to find an available port?

I have recently released a tiny library for doing just that with tests in mind. Maven dependency is:

<dependency>
    <groupId>me.alexpanov</groupId>
    <artifactId>free-port-finder</artifactId>
    <version>1.0</version>
</dependency>

Once installed, free port numbers can be obtained via:

int port = FreePortFinder.findFreeLocalPort();

Best practice for using assert?

An Assert is to check -
1. the valid condition,
2. the valid statement,
3. true logic;
of source code. Instead of failing the whole project it gives an alarm that something is not appropriate in your source file.

In example 1, since variable 'str' is not null. So no any assert or exception get raised.

Example 1:

#!/usr/bin/python

str = 'hello Python!'
strNull = 'string is Null'

if __debug__:
    if not str: raise AssertionError(strNull)
print str

if __debug__:
    print 'FileName '.ljust(30,'.'),(__name__)
    print 'FilePath '.ljust(30,'.'),(__file__)


------------------------------------------------------

Output:
hello Python!
FileName ..................... hello
FilePath ..................... C:/Python\hello.py

In example 2, var 'str' is null. So we are saving the user from going ahead of faulty program by assert statement.

Example 2:

#!/usr/bin/python

str = ''
strNull = 'NULL String'

if __debug__:
    if not str: raise AssertionError(strNull)
print str

if __debug__:
    print 'FileName '.ljust(30,'.'),(__name__)
    print 'FilePath '.ljust(30,'.'),(__file__)


------------------------------------------------------

Output:
AssertionError: NULL String

The moment we don't want debug and realized the assertion issue in the source code. Disable the optimization flag

python -O assertStatement.py
nothing will get print

Running Facebook application on localhost

2013 August. Facebook doesn't allow to set domain with port for an App, as example "localhost:3000".

So you can use https://pagekite.net to tunnel your localhost:port to proper domain.

Rails developers can use http://progrium.com/localtunnel/ for free.

Facebook allows only one domain for App at the time. If you are trying to add another one, as localhost, it will show some kind of different error about domain. Be sure to use only one domain for callback and for app domain setting at the time.

Custom Input[type="submit"] style not working with jquerymobile button

I'm assume you cannot get css working for your button using anchor tag. So you need to override the css styles which are being overwritten by other elements using !important property.

HTML

<a href="#" class="selected_btn" data-role="button">Button name</a>

CSS

.selected_btn
{
    border:1px solid red;
    text-decoration:none;
    font-family:helvetica;
    color:red !important;            
    background:url('http://www.lessardstephens.com/layout/images/slideshow_big.png') repeat-x;
}

Here is the demo

jQuery load more data on scroll

Here is an example:

On scrolling to the bottom, html elements are appeneded. This appending mechanism are only done twice, and then a button with powderblue color is appended at last.

_x000D_

<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
    <title>Demo: Lazy Loader</title>_x000D_
    <script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>_x000D_
    <style>_x000D_
        #myScroll {_x000D_
            border: 1px solid #999;_x000D_
        }_x000D_
_x000D_
        p {_x000D_
            border: 1px solid #ccc;_x000D_
            padding: 50px;_x000D_
            text-align: center;_x000D_
        }_x000D_
_x000D_
        .loading {_x000D_
            color: red;_x000D_
        }_x000D_
        .dynamic {_x000D_
            background-color:#ccc;_x000D_
            color:#000;_x000D_
        }_x000D_
    </style>_x000D_
    <script>_x000D_
  var counter=0;_x000D_
        $(window).scroll(function () {_x000D_
            if ($(window).scrollTop() == $(document).height() - $(window).height() && counter < 2) {_x000D_
                appendData();_x000D_
            }_x000D_
        });_x000D_
        function appendData() {_x000D_
            var html = '';_x000D_
            for (i = 0; i < 10; i++) {_x000D_
                html += '<p class="dynamic">Dynamic Data :  This is test data.<br />Next line.</p>';_x000D_
            }_x000D_
            $('#myScroll').append(html);_x000D_
   counter++;_x000D_
   _x000D_
   if(counter==2)_x000D_
   $('#myScroll').append('<button id="uniqueButton" style="margin-left: 50%; background-color: powderblue;">Click</button><br /><br />');_x000D_
        }_x000D_
    </script>_x000D_
</head>_x000D_
<body>_x000D_
    <div id="myScroll">_x000D_
        <p>_x000D_
            Contents will load here!!!.<br />_x000D_
        </p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
        <p >This is test data.<br />Next line.</p>_x000D_
    </div>_x000D_
</body>_x000D_
</html>

_x000D_

Trigger event when user scroll to specific element - with jQuery

I think your best bet would be to leverage an existing library that does that very thing:

http://imakewebthings.com/waypoints/

You can add listeners to your elements that will fire off when your element hits the top of the viewport:

$('#scroll-to').waypoint(function() {
 alert('you have scrolled to the h1!');
});

For an amazing demo of it in use:

http://tympanus.net/codrops/2013/07/16/on-scroll-header-effects/

OSError - Errno 13 Permission denied

You need to change the directory permission so that web server process can change the directory.

To change ownership of the directory, use chown:

chown -R user-id:group-id /path/to/the/directory

To see which user own the web server process (change httpd accordingly):

ps aux | grep httpd | grep -v grep

ps -efl | grep httpd | grep -v grep

Adding a newline character within a cell (CSV)

I have the same issue, when I try to export the content of email to csv and still keep it break line when importing to excel.

I export the conent as this: ="Line 1"&CHAR(10)&"Line 2"

When I import it to excel(google), excel understand it as string. It still not break new line.

We need to trigger excel to treat it as formula by: Format -> Number | Scientific.

This is not the good way but it resolve my issue.

How to get height and width of device display in angular2 using typescript?

For those who want to get height and width of device even when the display is resized (dynamically & in real-time):

Step 1:

In that Component do: import { HostListener } from "@angular/core";

Step 2:

In the component's class body write:

@HostListener('window:resize', ['$event'])
onResize(event?) {
   this.screenHeight = window.innerHeight;
   this.screenWidth = window.innerWidth;
}

Step 3:

In the component's constructor call the onResize method to initialize the variables. Also, don't forget to declare them first.

constructor() {
  this.onResize();
}

Complete code:

import { Component, OnInit } from "@angular/core";
import { HostListener } from "@angular/core";

@Component({
  selector: "app-login",
  templateUrl: './login.component.html',
  styleUrls: ['./login.component.css']
})

export class FooComponent implements OnInit {
    screenHeight: number;
    screenWidth: number;

    constructor() {
        this.getScreenSize();
    }

    @HostListener('window:resize', ['$event'])
    getScreenSize(event?) {
          this.screenHeight = window.innerHeight;
          this.screenWidth = window.innerWidth;
          console.log(this.screenHeight, this.screenWidth);
    }

}

Gson: Is there an easier way to serialize a map

In Gson 2.7.2 it's as easy as

Gson gson = new Gson();
String serialized = gson.toJson(map);

An implementation of the fast Fourier transform (FFT) in C#

Here's another; a C# port of the Ooura FFT. It's reasonably fast. The package also includes overlap/add convolution and some other DSP stuff, under the MIT license.

https://github.com/hughpyle/inguz-DSPUtil/blob/master/Fourier.cs

How do I add target="_blank" to a link within a specified div?

Use this for every external link

$('a[href^="http://"], a[href^="https://"]').attr('target', '_blank');

VBA Date as integer

Public SUB test()
    Dim mdate As Date
    mdate = now()
    MsgBox (Round(CDbl(mdate), 0))
End SUB

Why Anaconda does not recognize conda command?

Same problem with Anaconda running on Ubuntu 15.10. I closed the terminal and opened a new window and it worked fine.

Display TIFF image in all web browser

You can try converting your image from tiff to PNG, here is how to do it:

import com.sun.media.jai.codec.ImageCodec;
import com.sun.media.jai.codec.ImageDecoder;
import com.sun.media.jai.codec.ImageEncoder;
import com.sun.media.jai.codec.PNGEncodeParam;
import com.sun.media.jai.codec.TIFFDecodeParam;
import java.awt.image.RenderedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import javaxt.io.Image;

public class ImgConvTiffToPng {

    public static byte[] convert(byte[] tiff) throws Exception {

        byte[] out = new byte[0];
        InputStream inputStream = new ByteArrayInputStream(tiff);

        TIFFDecodeParam param = null;

        ImageDecoder dec = ImageCodec.createImageDecoder("tiff", inputStream, param);
        RenderedImage op = dec.decodeAsRenderedImage(0);

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

        PNGEncodeParam jpgparam = null;
        ImageEncoder en = ImageCodec.createImageEncoder("png", outputStream, jpgparam);
        en.encode(op);
        outputStream = (ByteArrayOutputStream) en.getOutputStream();
        out = outputStream.toByteArray();
        outputStream.flush();
        outputStream.close();

        return out;

    }

How to change the locale in chrome browser

Based from this thread, you need to bookmark chrome://settings/languages and then Drag and Drop the language to make it default. You have to click on the Display Google Chrome in this Language button and completely restart Chrome.

How to view instagram profile picture in full-size?

You can even set the prof. pic size to its high resolution that is '1080x1080'

replace "150x150" with 1080x1080 and remove /vp/ from the link.

Javascript - removing undefined fields from an object

Here's a plain javascript (no library required) solution:

function removeUndefinedProps(obj) {
    for (var prop in obj) {
        if (obj.hasOwnProperty(prop) && obj[prop] === undefined) {
            delete obj[prop];
        }
    }
}

Working demo: http://jsfiddle.net/jfriend00/djj5g5fu/

Eloquent get only one column as an array

You can use the pluck method:

Word_relation::where('word_one', $word_id)->pluck('word_two')->toArray();

For more info on what methods are available for using with collection, you can you can check out the Laravel Documentation.

Should I use int or Int32

You shouldn't care. You should use int most of the time. It will help the porting of your program to a wider architecture in the future (currently int is an alias to System.Int32 but that could change). Only when the bit width of the variable matters (for instance: to control the layout in memory of a struct) you should use int32 and others (with the associated "using System;").

Prevent scrolling of parent element when inner element scroll position reaches top/bottom?

Check out Leland Kwong's code.

Basic idea is to bind the wheeling event to the child element, and then use the native javascript property scrollHeight and the jquery property outerHeight of the child element to detect the end of the scroll, upon which return false to the wheeling event to prevent any scrolling.

var scrollableDist,curScrollPos,wheelEvent,dY;
$('#child-element').on('wheel', function(e){
  scrollableDist = $(this)[0].scrollHeight - $(this).outerHeight();
  curScrollPos = $(this).scrollTop();
  wheelEvent = e.originalEvent;
  dY = wheelEvent.deltaY;
  if ((dY>0 && curScrollPos >= scrollableDist) ||
      (dY<0 && curScrollPos <= 0)) {
    return false;
  }
});

How to Right-align flex item?

If you need one item to be left aligned (like a header) but then multiple items right aligned (like 3 images), then you would do something like this:

h1 {
   flex-basis: 100%; // forces this element to take up any remaining space
}

img {
   margin: 0 5px; // small margin between images
   height: 50px; // image width will be in relation to height, in case images are large - optional if images are already the proper size
}

Here's what that will look like (only relavent CSS was included in snippet above)

How do I reference a cell within excel named range?

There are a couple different ways I would do this:

1) Mimic Excel Tables Using with a Named Range

In your example, you named the range A10:A20 "Age". Depending on how you wanted to reference a cell in that range you could either (as @Alex P wrote) use =INDEX(Age, 5) or if you want to reference a cell in range "Age" that is on the same row as your formula, just use:

=INDEX(Age, ROW()-ROW(Age)+1)

This mimics the relative reference features built into Excel tables but is an alternative if you don't want to use a table.

If the named range is an entire column, the formula simplifies as:

=INDEX(Age, ROW())

2) Use an Excel Table

Alternatively if you set this up as an Excel table and type "Age" as the header title of the Age column, then your formula in columns to the right of the Age column can use a formula like this:

=[@[Age]]

@Nullable annotation usage

It makes it clear that the method accepts null values, and that if you override the method, you should also accept null values.

It also serves as a hint for code analyzers like FindBugs. For example, if such a method dereferences its argument without checking for null first, FindBugs will emit a warning.

Set cellpadding and cellspacing in CSS?

You can check the below code just create a index.html and run it.

_x000D_

<!DOCTYPE html>
<html>

<head>
  <style>
    table {
      border-spacing: 10px;
    }
    
    td {
      padding: 10px;
    }
  </style>
</head>

<body>
  <table cellspacing="0" cellpadding="0">
    <th>Col 1</th>
    <th>Col 2</th>
    <th>Col 3</th>
    <tr>
      <td>1</td>
      <td>2</td>
      <td>3</td>
    </tr>
  </table>
</body>

</html>

_x000D_

OUTPUT :

Experimental decorators warning in TypeScript compilation

You can run with this code

 tsc .\src\index.ts --experimentalDecorators "true" --emitDecoratorMetadata "true"

How can I select records ONLY from yesterday?

This comment is for readers who have found this entry but are using mysql instead of oracle! on mysql you can do the following: Today

SELECT  * 
FROM 
WHERE date(tran_date) = CURRENT_DATE()

Yesterday

SELECT  * 
FROM yourtable 
WHERE date(tran_date) = DATE_SUB(CURRENT_DATE(), INTERVAL 1 DAY)

Escaping double quotes in JavaScript onClick event handler

You may also want to try two backslashes (\\") to escape the escape character.

Using onBlur with JSX and React

There are a few problems here.

1: onBlur expects a callback, and you are calling renderPasswordConfirmError and using the return value, which is null.

2: you need a place to render the error.

3: you need a flag to track "and I validating", which you would set to true on blur. You can set this to false on focus if you want, depending on your desired behavior.

handleBlur: function () {
  this.setState({validating: true});
},
render: function () {
  return <div>
    ...
    <input
        type="password"
        placeholder="Password (confirm)"
        valueLink={this.linkState('password2')}
        onBlur={this.handleBlur}
     />
    ...
    {this.renderPasswordConfirmError()}
  </div>
},
renderPasswordConfirmError: function() {
  if (this.state.validating && this.state.password !== this.state.password2) {
    return (
      <div>
        <label className="error">Please enter the same password again.</label>
      </div>
    );
  }  
  return null;
},

visual c++: #include files from other projects in the same solution

Since both projects are under the same solution, there's a simpler way for the include files and linker as described in https://docs.microsoft.com/en-us/cpp/build/adding-references-in-visual-cpp-projects?view=vs-2019 :

The include can be written in a relative path (E.g. #include "../libProject/libHeader.h").
For the linker, right click on "References", Click on Add Reference, and choose the other project.

Shortcut to create properties in Visual Studio?

Place cursor inside your field private int _i; and then Edit menu or RMB - Refactor - Encapsulate Field... (CtrlR, CtrlE) to create the standard property accessors.

open link of google play store in mobile version android

You'll want to use the specified market protocol:

final String appPackageName = "com.example"; // Can also use getPackageName(), as below
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=" + appPackageName)));

Keep in mind, this will crash on any device that does not have the Market installed (the emulator, for example). Hence, I would suggest something like:

final String appPackageName = getPackageName(); // getPackageName() from Context or Activity object
try {
    startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("market://details?id=" + appPackageName)));
} catch (android.content.ActivityNotFoundException anfe) {
    startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://play.google.com/store/apps/details?id=" + appPackageName)));
}

While using getPackageName() from Context or subclass thereof for consistency (thanks @cprcrack!). You can find more on Market Intents here: link.

How to hide axes and gridlines in Matplotlib (python)

Turn the axes off with:

plt.axis('off')

And gridlines with:

plt.grid(b=None)

Disable cross domain web security in Firefox

I have not been able to find a Firefox option equivalent of --disable-web-security or an addon that does that for me. I really needed it for some testing scenarios where modifying the web server was not possible. What did help was to use Fiddler to auto-modify web responses so that they have the correct headers and CORS is no longer an issue.

The steps are:

Open fiddler.
If on https go to menu Tools -> Options -> Https and tick the Capture & Decrypt https options

Go to menu Rules -> Customize rules. Modify the OnBeforeResponseFunction so that it looks like the following, then save:

 static function OnBeforeResponse(oSession: Session) {
    //....
    oSession.oResponse.headers.Remove("Access-Control-Allow-Origin");
    oSession.oResponse.headers.Add("Access-Control-Allow-Origin", "*");
    //...
 }

This will make every web response to have the Access-Control-Allow-Origin: * header.

This still won't work as the OPTIONS preflight will pass through and cause the request to block before our above rule gets the chance to modify the headers. So to fix this, in the fiddler main window, on the right hand side there's an AutoResponder tab. Add a new rule and response: METHOD:OPTIONS https://yoursite.com/ with auto response: *CORSPreflightAllow and tick the boxes: "Enable Rules" and "Unmatched requests passthrough".

See picture below for reference:

Remote branch is not showing up in "git branch -r"

Unfortunately, git branch -a and git branch -r do not show you all remote branches, if you haven't executed a "git fetch".

git remote show origin works consistently all the time. Also git show-ref shows all references in the Git repository. However, it works just like the git branch command.

PHP - Check if two arrays are equal

Compare them as other values:

if($array_a == $array_b) {
  //they are the same
}

You can read about all array operators here: http://php.net/manual/en/language.operators.array.php Note for example that === also checks that the types and order of the elements in the arrays are the same.

phpmyadmin "Not Found" after install on Apache, Ubuntu

Finally I got the solution

sudo ln -s /etc/phpmyadmin/apache.conf /etc/apache2/conf-available/phpmyadmin.conf
sudo a2enconf phpmyadmin
sudo service apache2 reload

More about https://askubuntu.com/questions/55280/phpmyadmin-is-not-working-after-i-installed-it

Can you have if-then-else logic in SQL?

Please check whether this helps:

select TOP 1
    product, 
    price 
from 
    table1 
where 
    (project=1 OR Customer=2 OR company=3) AND
    price IS NOT NULL
ORDER BY company

Uncaught SyntaxError: Unexpected token with JSON.parse

The error you are getting i.e. "unexpected token o" is because json is expected but object is obtained while parsing. That "o" is the first letter of word "object".

Integrating the ZXing library directly into my Android application

2020 UPDATE: Just add this to your Gradle file. It works perfectly!

repositories {
   jcenter()
}
implementation 'me.dm7.barcodescanner:zxing:1.9.13'

How do I initialize a dictionary of empty lists in Python?

Use defaultdict instead:

from collections import defaultdict
data = defaultdict(list)
data[1].append('hello')

This way you don't have to initialize all the keys you want to use to lists beforehand.

What is happening in your example is that you use one (mutable) list:

alist = [1]
data = dict.fromkeys(range(2), alist)
alist.append(2)
print data

would output {0: [1, 2], 1: [1, 2]}.

How do I invert BooleanToVisibilityConverter?

Instead of inverting, you can achieve the same goal by using a generic IValueConverter implementation that can convert a Boolean value to configurable target values for true and false. Below is one such implementation:

public class BooleanConverter<T> : IValueConverter
{
    public BooleanConverter(T trueValue, T falseValue)
    {
        True = trueValue;
        False = falseValue;
    }

    public T True { get; set; }
    public T False { get; set; }

    public virtual object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return value is bool && ((bool) value) ? True : False;
    }

    public virtual object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return value is T && EqualityComparer<T>.Default.Equals((T) value, True);
    }
}

Next, subclass it where T is Visibility:

public sealed class BooleanToVisibilityConverter : BooleanConverter<Visibility>
{
    public BooleanToVisibilityConverter() : 
        base(Visibility.Visible, Visibility.Collapsed) {}
}

Finally, this is how you could use BooleanToVisibilityConverter above in XAML and configure it to, for example, use Collapsed for true and Visible for false:

<Application.Resources>
    <app:BooleanToVisibilityConverter 
        x:Key="BooleanToVisibilityConverter" 
        True="Collapsed" 
        False="Visible" />
</Application.Resources>

This inversion is useful when you want to bind to a Boolean property named IsHidden as opposed IsVisible.

Check if object value exists within a Javascript array of objects and if not add a new object to array

Here is an ES6 method chain using .map() and .includes():

const arr = [ { id: 1, username: 'fred' }, { id: 2, username: 'bill' }, { id: 2, username: 'ted' } ]

const checkForUser = (newUsername) => {
      arr.map(user => {
        return user.username
      }).includes(newUsername)
    }

if (!checkForUser('fred')){
  // add fred
}

Map over existing users to create array of username strings.
Check if that array of usernames includes the new username
If it's not present, add the new user

Sublime Text 3 how to change the font size of the file sidebar?

I followed these instructions but then found that the menu hover color was wrong.

I am using the Spacegray theme in Sublime 3 beta 3074. So to accomplish the sidebar font color change and also hover color change, on OSX, I created a new file ~/Library/"Application Support"/"Sublime Text 3"/Packages/User/Spacegray.sublime-theme

then added this code to it:

[
    {
        "class": "sidebar_label",
        "color": [192,197,203],
        "font.bold": false,
        "font.size": 15
    },
     {
        "class": "sidebar_label",
        "parents": [{"class": "tree_row","attributes": ["hover"]}],
        "color": [255,255,255] 
    },
]

It is possible to tweak many other settings for your theme if you can see the original default:

https://gist.github.com/nateflink/0355eee823b89fe7681e

I extracted this file from the sublime package zip file by installing the PackageResourceViewer following MattDMo's instructions (https://stackoverflow.com/users/1426065/mattdmo) here:

How to change default code snippets in Sublime Text 3?

What is path of JDK on Mac ?

Which Mac version are you using? try these paths

 /System/Library/Frameworks/JavaVM.framework/ OR
 /usr/libexec/java_home

This link might help - How To Set $JAVA_HOME Environment Variable On Mac OS X

how to loop through each row of dataFrame in pyspark

It might not be the best practice, but you can simply target a specific column using collect(), export it as a list of Rows, and loop through the list.

Assume this is your df:

+----------+----------+-------------------+-----------+-----------+------------------+ 
|      Date|  New_Date|      New_Timestamp|date_sub_10|date_add_10|time_diff_from_now|
+----------+----------+-------------------+-----------+-----------+------------------+ 
|2020-09-23|2020-09-23|2020-09-23 00:00:00| 2020-09-13| 2020-10-03| 51148            | 
|2020-09-24|2020-09-24|2020-09-24 00:00:00| 2020-09-14| 2020-10-04| -35252           |
|2020-01-25|2020-01-25|2020-01-25 00:00:00| 2020-01-15| 2020-02-04| 20963548         |
|2020-01-11|2020-01-11|2020-01-11 00:00:00| 2020-01-01| 2020-01-21| 22173148         |
+----------+----------+-------------------+-----------+-----------+------------------+

to loop through rows in Date column:

rows = df3.select('Date').collect()

final_list = []
for i in rows:
    final_list.append(i[0])

print(final_list)

Maven: add a folder or jar file into current classpath

From docs and example it is not clear that classpath manipulation is not allowed.

<configuration>
 <compilerArgs>
  <arg>classpath=${basedir}/lib/bad.jar</arg>
 </compilerArgs>
</configuration>

But see Java docs (also https://www.cis.upenn.edu/~bcpierce/courses/629/jdkdocs/tooldocs/solaris/javac.html)

-classpath path Specifies the path javac uses to look up classes needed to run javac or being referenced by other classes you are compiling. Overrides the default or the CLASSPATH environment variable if it is set.

Maybe it is possible to get current classpath and extend it,
see in maven, how output the classpath being used?

    <properties>
      <cpfile>cp.txt</cpfile>
    </properties>

  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-dependency-plugin</artifactId>
    <version>2.9</version>
    <executions>
      <execution>
        <id>build-classpath</id>
        <phase>generate-sources</phase>
        <goals>
          <goal>build-classpath</goal>
        </goals>
        <configuration>
          <outputFile>${cpfile}</outputFile>
        </configuration>
      </execution>
    </executions>
  </plugin>

Read file (Read a file into a Maven property)

<plugin>
  <groupId>org.codehaus.gmaven</groupId>
  <artifactId>gmaven-plugin</artifactId>
  <version>1.4</version>
  <executions>
    <execution>
      <phase>generate-resources</phase>
      <goals>
        <goal>execute</goal>
      </goals>
      <configuration>
        <source>
          def file = new File(project.properties.cpfile)
          project.properties.cp = file.getText()
        </source>
      </configuration>
    </execution>
  </executions>
</plugin>

and finally

  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.6.1</version>
    <configuration>
      <compilerArgs>
         <arg>classpath=${cp}:${basedir}/lib/bad.jar</arg>
      </compilerArgs>
    </configuration>
   </plugin>

Is there a download function in jsFiddle?

Adding /show does not present a pure source code, it's an embedded working example. To display it without any additional scripts, css and html, use:

http://fiddle.jshell.net/<fiddle id>/show/light/

An example: http://fiddle.jshell.net/Ua8Cv/show/light/

How can I get a channel ID from YouTube?

You can get the channel ID with the username (in your case "klauskkpm") using the filter "forUsername", like this:

https://www.googleapis.com/youtube/v3/channels?key={YOUR_API_KEY}&forUsername=klauskkpm&part=id

More info here: https://developers.google.com/youtube/v3/docs/channels/list

Attempt to present UIViewController on UIViewController whose view is not in the window hierarchy

Swift 5

I call present in viewDidLayoutSubviews as presenting in viewDidAppear causes a split second showing of the view controller before the modal is loaded which looks like an ugly glitch

make sure to check for the window existence and execute code just once

var alreadyPresentedVCOnDisplay = false

override func viewDidLayoutSubviews() {
        
    super.viewDidLayoutSubviews()
    
    // we call present in viewDidLayoutSubviews as
    // presenting in viewDidAppear causes a split second showing 
    // of the view controller before the modal is loaded
    
    guard let _ = view?.window else {
        // window must be assigned
        return
    }
    
    if !alreadyPresentedVCOnDisplay {
        alreadyPresentedVCOnDisplay = true
        present(...)
    }
    
}

Best way to use PHP to encrypt and decrypt passwords?

Security warning: This code is not secure.

working example

define('SALT', 'whateveryouwant'); 

function encrypt($text) 
{ 
    return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, SALT, $text, MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND)))); 
} 

function decrypt($text) 
{ 
    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, SALT, base64_decode($text), MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND))); 
} 

$encryptedmessage = encrypt("your message"); 
echo decrypt($encryptedmessage);

Windows error 2 occured while loading the Java VM

In cmd

C:\Users\Downloads>install.exe LAX_VM "C:\Program Files\Java\jdk1.8.0_60\bin\java.exe"

Eliminating duplicate values based on only one column of the table

This is where the window function row_number() comes in handy:

SELECT s.siteName, s.siteIP, h.date
FROM sites s INNER JOIN
     (select h.*, row_number() over (partition by siteName order by date desc) as seqnum
      from history h
     ) h
    ON s.siteName = h.siteName and seqnum = 1
ORDER BY s.siteName, h.date

Read pdf files with php

There is a php library (pdfparser) that does exactly what you want.

project website

http://www.pdfparser.org/

github

https://github.com/smalot/pdfparser

Demo page/api

http://www.pdfparser.org/demo

After including pdfparser in your project you can get all text from mypdf.pdf like so:

<?php
$parser = new \installpath\PdfParser\Parser();
$pdf    = $parser->parseFile('mypdf.pdf');  
$text = $pdf->getText();
echo $text;//all text from mypdf.pdf

?>

Simular you can get the metadata from the pdf as wel as getting the pdf objects (for example images).

Python AttributeError: 'module' object has no attribute 'Serial'

This error can also happen if you have circular dependencies. Check your imports and make sure you do not have any cycles.

How to align this span to the right of the div?

An alternative solution to floats is to use absolute positioning:

.title {
  position: relative;
}

.title span:last-child {
  position: absolute;
  right: 6px;   /* must be equal to parent's right padding */
}

Google Maps: Auto close open InfoWindows?

Declare a variable for active window

var activeInfoWindow;

and bind this code in marker listener

 marker.addListener('click', function () {
    if (activeInfoWindow) { activeInfoWindow.close();}
    infowindow.open(map, marker);
    activeInfoWindow = infowindow;
});

How to achieve pagination/table layout with Angular.js?

I use this solution:

It's a bit more concise since I use: ng-repeat="obj in objects | filter : paginate" to filter the rows. Also made it working with $resource:

http://plnkr.co/edit/79yrgwiwvan3bAG5SnKx?p=preview

jQuery animate margin top

check this same effect with less code

$(".item").mouseover(function(){
    $('.info').animate({ marginTop: '-50px' , opacity: 0.5 }, 1000);
});

View recent fiddle

How to uninstall/upgrade Angular CLI?

remove global reference

npm uninstall -g angular-cli
npm cache clean

Error: Failed to lookup view in Express

I had the same issue and could fix it with the solution from dougwilson: from Apr 5, 2017, Github.

I changed the filename from index.js to index.pug
Then used in the '/' route: res.render('index.pug') - instead of res.render('index')
Set environment variable: DEBUG=express:view Now it works like a charm.

How do I add a margin between bootstrap columns without wrapping

You should work with padding on the inner container rather than with margin. Try this!

HTML

<div class="row info-panel">
    <div class="col-md-4" id="server_1">
       <div class="server-action-menu">
           Server 1
       </div>
   </div>
</div>

CSS

.server-action-menu {
    background-color: transparent;
    background-image: linear-gradient(to bottom, rgba(30, 87, 153, 0.2) 0%, rgba(125, 185, 232, 0) 100%);
    background-repeat: repeat;
    border-radius:10px;
    padding: 5px;
}

How can I get my webapp's base URL in ASP.NET MVC?

@{
    var baseurl = Request.Url.Scheme + "://" + Request.Url.Host + ":" + Request.Url.Port + Url.Content("~");
}
@baseurl

--output http://localhost:49626/TEST/

Time complexity of nested for-loop

First we'll consider loops where the number of iterations of the inner loop is independent of the value of the outer loop's index. For example:

 for (i = 0; i < N; i++) {
     for (j = 0; j < M; j++) {
         sequence of statements
      }
  }

The outer loop executes N times. Every time the outer loop executes, the inner loop executes M times. As a result, the statements in the inner loop execute a total of N * M times. Thus, the total complexity for the two loops is O(N2).

System.Net.WebException: The remote name could not be resolved:

Open the hosts file located at : **C:\windows\system32\drivers\etc**.

Hosts file is for what?

Add the following at end of this file :

YourServerIP YourDNS

Example:

198.168.1.1 maps.google.com

Remove last specific character in a string c#

Try below

Something..TrimEnd(",".ToCharArray());

how to use "AND", "OR" for RewriteCond on Apache?

This is an interesting question and since it isn't explained very explicitly in the documentation I'll answer this by going through the sourcecode of mod_rewrite; demonstrating a big benefit of open-source.

In the top section you'll quickly spot the defines used to name these flags:

#define CONDFLAG_NONE               1<<0
#define CONDFLAG_NOCASE             1<<1
#define CONDFLAG_NOTMATCH           1<<2
#define CONDFLAG_ORNEXT             1<<3
#define CONDFLAG_NOVARY             1<<4

and searching for CONDFLAG_ORNEXT confirms that it is used based on the existence of the [OR] flag:

else if (   strcasecmp(key, "ornext") == 0
         || strcasecmp(key, "OR") == 0    ) {
    cfg->flags |= CONDFLAG_ORNEXT;
}

The next occurrence of the flag is the actual implementation where you'll find the loop that goes through all the RewriteConditions a RewriteRule has, and what it basically does is (stripped, comments added for clarity):

# loop through all Conditions that precede this Rule
for (i = 0; i < rewriteconds->nelts; ++i) {
    rewritecond_entry *c = &conds[i];

    # execute the current Condition, see if it matches
    rc = apply_rewrite_cond(c, ctx);

    # does this Condition have an 'OR' flag?
    if (c->flags & CONDFLAG_ORNEXT) {
        if (!rc) {
            /* One condition is false, but another can be still true. */
            continue;
        }
        else {
            /* skip the rest of the chained OR conditions */
            while (   i < rewriteconds->nelts
                   && c->flags & CONDFLAG_ORNEXT) {
                c = &conds[++i];
            }
        }
    }
    else if (!rc) {
        return 0;
    }
}

You should be able to interpret this; it means that OR has a higher precedence, and your example indeed leads to if ( (A OR B) AND (C OR D) ). If you would, for example, have these Conditions:

RewriteCond A [or]
RewriteCond B [or]
RewriteCond C
RewriteCond D

it would be interpreted as if ( (A OR B OR C) and D ).

CodeIgniter : Unable to load the requested file:

I was getting this error in PyroCMS.

You can improve the error message in the Loader.php file that is in the code of the library.

Open the Loader.php file and find any calls to show_error. I replaced mine with the following:

show_error(sprintf("Unable to load the requested file: \"%s\" with instance title of \"%s\"", $_ci_file, $_ci_data['_ci_vars']['options']['instance_title']));

I was then able to see which file was causing the issues for me.

How do I remove files saying "old mode 100755 new mode 100644" from unstaged changes in Git?

You could try git reset --hard HEAD to reset the repo to the expected default state.

How to launch an application from a browser?

We use a sonicwall vpn. It launches a java applet that launches mstc with all the credentials setup. You really can't do this without a java applet or activex plugin.

Microsoft uses this technique itself on their small business server for getting inside the network. I wouldn't say it is a terrible idea, as long as platform independence isn't important.

Getting 404 Not Found error while trying to use ErrorDocument

The ErrorDocument directive, when supplied a local URL path, expects the path to be fully qualified from the DocumentRoot. In your case, this means that the actual path to the ErrorDocument is

ErrorDocument 404 /hellothere/error/404page.html

Better way to check variable for null or empty string?

There is no better way but since it's an operation you usually do quite often, you'd better automatize the process.

Most frameworks offer a way to make arguments parsing an easy task. You can build you own object for that. Quick and dirty example :

class Request
{

    // This is the spirit but you may want to make that cleaner :-)
    function get($key, $default=null, $from=null)
    {
         if ($from) :
             if (isset(${'_'.$from}[$key]));
                return sanitize(${'_'.strtoupper($from)}[$key]); // didn't test that but it should work
         else
             if isset($_REQUEST[$key])
                return sanitize($_REQUEST[$key]);

         return $default;
    }

    // basics. Enforce it with filters according to your needs
    function sanitize($data)
    {
          return addslashes(trim($data));
    }

    // your rules here
    function isEmptyString($data)
    {
        return (trim($data) === "" or $data === null);
    }


    function exists($key) {}

    function setFlash($name, $value) {}

    [...]

}

$request = new Request();
$question= $request->get('question', '', 'post');
print $request->isEmptyString($question);

Symfony use that kind of sugar massively.

But you are talking about more than that, with your "// Handle error here ". You are mixing 2 jobs : getting the data and processing it. This is not the same at all.

There are other mechanisms you can use to validate data. Again, frameworks can show you best pratices.

Create objects that represent the data of your form, then attach processses and fall back to it. It sounds far more work that hacking a quick PHP script (and it is the first time), but it's reusable, flexible, and much less error prone since form validation with usual PHP tends to quickly become spaguetti code.

How to set environment variables in Python?

to Set Variable:

item Assignment method using key:

import os    
os.environ['DEBUSSY'] = '1'  #Environ Variable must be string not Int

to get or to check whether its existed or not,

since os.environ is an instance you can try object way.

Method 1:

os.environ.get('DEBUSSY') # this is error free method if not will return None by default

will get '1' as return value

Method 2:

os.environ['DEBUSSY'] # will throw an key error if not found!

Method 3:

'DEBUSSY' in os.environ  # will return Boolean True/False

Method 4:

os.environ.has_key('DEBUSSY') #last 2 methods are Boolean Return so can use for conditional statements

What is the best way to generate a unique and short file name in Java

Problem is synchronization. Separate out regions of conflict.

Name the file as : (server-name)_(thread/process-name)_(millisecond/timestamp).(extension)
example : aws1_t1_1447402821007.png

Recover from git reset --hard?

In case you're using VS Code and happen to have the affected files open, you can undo the changes made by Git on a per-file basis. (so CTRL + Z)

How to parse a text file with C#

Try regular expressions. You can find a certain pattern in your text and replace it with something that you want. I can't give you the exact code right now but you can test out your expressions using this.

http://www.radsoftware.com.au/regexdesigner/

Find Active Tab using jQuery and Twitter Bootstrap

First of all you need to remove the data-toggle attribute. We will use some JQuery, so make sure you include it.

  <ul class='nav nav-tabs'>
    <li class='active'><a href='#home'>Home</a></li>
    <li><a href='#menu1'>Menu 1</a></li>
    <li><a href='#menu2'>Menu 2</a></li>
    <li><a href='#menu3'>Menu 3</a></li>
  </ul>

  <div class='tab-content'>
    <div id='home' class='tab-pane fade in active'>
      <h3>HOME</h3>
    <div id='menu1' class='tab-pane fade'>
      <h3>Menu 1</h3>
    </div>
    <div id='menu2' class='tab-pane fade'>
      <h3>Menu 2</h3>
    </div>
    <div id='menu3' class='tab-pane fade'>
      <h3>Menu 3</h3>
    </div>
  </div>
</div>

<script>
$(document).ready(function(){
// Handling data-toggle manually
    $('.nav-tabs a').click(function(){
        $(this).tab('show');
    });
// The on tab shown event
    $('.nav-tabs a').on('shown.bs.tab', function (e) {
        alert('Hello from the other siiiiiide!');
        var current_tab = e.target;
        var previous_tab = e.relatedTarget;
    });
});
</script>

How to display the string html contents into webbrowser control?

The DisplayHtml(string html) recommended by m3z worked for me.

In case it helps somebody, I would also like to mention that initially there were some spaces in my HTML that invalidated the HTML and so the text appeared as a string. The spaces were introduced (around the angular brackets) when I pasted the HTML into Visual Studio. So if your text is still appearing as text after you try the solutions mentioned in this post, then it may be worth checking that the HTML syntax is correct.

git - remote add origin vs remote set-url origin

Below will reinitialize your local repo; also clearing remote repos (ie origin):

git init

Then below, will create 'origin' if it doesn't exist:

git remote add origin [repo-url]

Else, you can use the set-url subcommand to edit an existing remote:

git remote set-url origin [repo-url]

Also, you can check existing remotes with

git remote -v

Hope this helps!

pretty-print JSON using JavaScript

You can use console.dir(), which is a shortcut for console.log(util.inspect()). (The only difference is that it bypasses any custom inspect() function defined on an object.)

It uses syntax-highlighting, smart indentation, removes quotes from keys and just makes the output as pretty as it gets.

const object = JSON.parse(jsonString)

console.dir(object, {depth: null, colors: true})

and for the command line:

cat package.json | node -e "process.stdin.pipe(new stream.Writable({write: chunk => console.dir(JSON.parse(chunk), {depth: null, colors: true})}))"

Using variables inside a bash heredoc

As a late corolloary to the earlier answers here, you probably end up in situations where you want some but not all variables to be interpolated. You can solve that by using backslashes to escape dollar signs and backticks; or you can put the static text in a variable.

Name='Rich Ba$tard'
dough='$$$dollars$$$'
cat <<____HERE
$Name, you can win a lot of $dough this week!
Notice that \`backticks' need escaping if you want
literal text, not `pwd`, just like in variables like
\$HOME (current value: $HOME)
____HERE

Demo: https://ideone.com/rMF2XA

Note that any of the quoting mechanisms -- \____HERE or "____HERE" or '____HERE' -- will disable all variable interpolation, and turn the here-document into a piece of literal text.

A common task is to combine local variables with script which should be evaluated by a different shell, programming language, or remote host.

local=$(uname)
ssh -t remote <<:
    echo "$local is the value from the host which ran the ssh command"
    # Prevent here doc from expanding locally; remote won't see backslash
    remote=\$(uname)
    # Same here
    echo "\$remote is the value from the host we ssh:ed to"
:

How can I create directory tree in C++/Linux?

The others got you the right answer, but I thought I'd demonstrate another neat thing you can do:

mkdir -p /tmp/a/{b,c}/d

Will create the following paths:

/tmp/a/b/d
/tmp/a/c/d

The braces allow you to create multiple directories at once on the same level of the hierarchy, whereas the -p option means "create parent directories as needed".

How to change the default GCC compiler in Ubuntu?

In case you want a quicker (but still very clean) way of achieving it for a personal purpose (for instance if you want to build a specific project having some strong requirements concerning the version of the compiler), just follow the following steps:

type echo $PATH and look for a personal directory having a very high priority (in my case, I have ~/.local/bin);
add the symbolic links in this directory:

For instance:

ln -s /usr/bin/gcc-WHATEVER ~/.local/bin/gcc
ln -s /usr/bin/g++-WHATEVER ~/.local/bin/g++

Of course, this will work for a single user (it isn't a system wide solution), but on the other hand I don't like to change too many things in my installation.

Convert a timedelta to days, hours and minutes

If you have a datetime.timedelta value td, td.days already gives you the "days" you want. timedelta values keep fraction-of-day as seconds (not directly hours or minutes) so you'll indeed have to perform "nauseatingly simple mathematics", e.g.:

def days_hours_minutes(td):
    return td.days, td.seconds//3600, (td.seconds//60)%60

The pipe ' ' could not be found angular2 custom pipe

Make sure you are not facing a "cross module" problem

If the component which is using the pipe, doesn't belong to the module which has declared the pipe component "globally" then the pipe is not found and you get this error message.

In my case I've declared the pipe in a separate module and imported this pipe module in any other module having components using the pipe.

I have declared a that the component in which you are using the pipe is

the Pipe Module

 import { NgModule }      from '@angular/core';
 import { myDateFormat }          from '../directives/myDateFormat';

 @NgModule({
     imports:        [],
     declarations:   [myDateFormat],
     exports:        [myDateFormat],
 })

 export class PipeModule {

   static forRoot() {
      return {
          ngModule: PipeModule,
          providers: [],
      };
   }
 }

Usage in another module (e.g. app.module)

  // Import APPLICATION MODULES
  ...
  import { PipeModule }    from './tools/PipeModule';

  @NgModule({
     imports: [
    ...
    , PipeModule.forRoot()
    ....
  ],

twitter bootstrap text-center when in xs mode

Use bs3-upgrade library for spacings and text aligment...

https://github.com/studija/bs3-upgrade

col-xs-text-center col-sm-text-left

col-xs-text-center col-sm-text-right

<div class="container">
    <div class="row">
        <div class="col-xs-12 col-sm-6 col-xs-text-center col-sm-text-left">
            <p>
                &copy; 2015 example.com. All rights reserved.
            </p>
        </div>
        <div class="col-xs-12 col-sm-6 col-xs-text-center col-sm-text-right">
            <p>
                <a href="#"><i class="fa fa-facebook"></i></a> 
                <a href="#"><i class="fa fa-twitter"></i></a> 
                <a href="#"><i class="fa fa-google-plus"></i></a>
            </p>
        </div>
    </div>
</div>

Cannot convert lambda expression to type 'string' because it is not a delegate type

For people just stumbling upon this now, I resolved an error of this type that was thrown with all the references and using statements placed properly. There's evidently some confusion with substituting in a function that returns DataTable instead of calling it on a declared DataTable. For example:

This worked for me:

DataTable dt = SomeObject.ReturnsDataTable();

List<string> ls = dt.AsEnumerable().Select(dr => dr["name"].ToString()).ToList<string>();

But this didn't:

List<string> ls = SomeObject.ReturnsDataTable().AsEnumerable().Select(dr => dr["name"].ToString()).ToList<string>();

I'm still not 100% sure why, but if anyone is frustrated by an error of this type, give this a try.

How to get the previous page URL using JavaScript?

<script type="text/javascript">
    document.write(document.referrer);
</script>

document.referrer serves your purpose, but it doesn't work for Internet Explorer versions earlier than IE9.

It will work for other popular browsers, like Chrome, Mozilla, Opera, Safari etc.

How do I write a SQL query for a specific date range and date time using SQL Server 2008?

You can try this:

SELECT * FROM MYTABLE WHERE DATE BETWEEN '03/10/2014 06:25:00' and '03/12/2010 6:25:00'

Is there a naming convention for git repositories?

lowercase-with-hyphens is the style I most often see on GitHub.*

lowercase_with_underscores is probably the second most popular style I see.

The former is my preference because it saves keystrokes.

^{* Anecdotal; I haven't collected any data.}

phpmysql error - #1273 - #1273 - Unknown collation: 'utf8mb4_general_ci'

There are two steps to fix this.

First edit phpMyAdmin/libraries/DatabaseInterface.class.php

Change:

    if (PMA_MYSQL_INT_VERSION >  50503) {
        $default_charset = 'utf8mb4';
        $default_collation = 'utf8mb4_general_ci';
    } else {
        $default_charset = 'utf8';
        $default_collation = 'utf8_general_ci';
    }

To:

    //if (PMA_MYSQL_INT_VERSION >  50503) {
    //    $default_charset = 'utf8mb4';
    //    $default_collation = 'utf8mb4_general_ci';
    //} else {
        $default_charset = 'utf8';
        $default_collation = 'utf8_general_ci';
    //}

Then delete this cookie from your browser "pma_collation_connection".
Or delete all Cookies.

Then restart your phpMyAdmin.

(It would be nice if phpMyAdmin allowed you to set the charset and collation per server in the config.inc.php)

Why are there two ways to unstage a file in Git?

git rm --cached is used to remove a file from the index. In the case where the file is already in the repo, git rm --cached will remove the file from the index, leaving it in the working directory and a commit will now remove it from the repo as well. Basically, after the commit, you would have unversioned the file and kept a local copy.

git reset HEAD file ( which by default is using the --mixed flag) is different in that in the case where the file is already in the repo, it replaces the index version of the file with the one from repo (HEAD), effectively unstaging the modifications to it.

In the case of unversioned file, it is going to unstage the entire file as the file was not there in the HEAD. In this aspect git reset HEAD file and git rm --cached are same, but they are not same ( as explained in the case of files already in the repo)

To the question of Why are there 2 ways to unstage a file in git? - there is never really only one way to do anything in git. that is the beauty of it :)

What is content-type and datatype in an AJAX request?

See http://api.jquery.com/jQuery.ajax/, there's mention of datatype and contentType there.

They are both used in the request to the server so the server knows what kind of data to receive/send.

json: cannot unmarshal object into Go value of type

Determining of root cause is not an issue since Go 1.8; field name now is shown in the error message:

json: cannot unmarshal object into Go struct field Comment.author of type string

set option "selected" attribute from dynamic created option

I was trying something like this using the $(...).val() function, but the function did not exist. It turns out that you can manually set the value the same way you do it for an <input>:

// Set value to Indonesia ("ID"):
$('#country').value = 'ID'

...and it get's automatically updated in the select. Works on Firefox at least; you might want to try it out in the others.

UDP vs TCP, how much faster is it?

with loss tolerant

Do you mean "with loss tolerance" ?

Basically, UDP is not "loss tolerant". You can send 100 packets to someone, and they might only get 95 of those packets, and some might be in the wrong order.

For things like video streaming, and multiplayer gaming, where it is better to miss a packet than to delay all the other packets behind it, this is the obvious choice

For most other things though, a missing or 'rearranged' packet is critical. You'd have to write some extra code to run on top of UDP to retry if things got missed, and enforce correct order. This would add a small bit of overhead in certain places.

Thankfully, some very very smart people have done this, and they called it TCP.

Think of it this way: If a packet goes missing, would you rather just get the next packet as quickly as possible and continue (use UDP), or do you actually need that missing data (use TCP). The overhead won't matter unless you're in a really edge-case scenario.

functional way to iterate over range (ES6/7)

One can create an empty array, fill it (otherwise map will skip it) and then map indexes to values:

Array(8).fill().map((_, i) => i * i);

Decreasing height of bootstrap 3.0 navbar

If you guys are generating your stylesheets with LESS/SASS and are importing Bootstrap there, I've found that overriding the @navbar-height variable lets your set the height of the navbar, which is originally defined in the variables.less file.

PHP array value passes to next row

Change the checkboxes so that the name includes the index inside the brackets:

<input type="checkbox" class="checkbox_veh" id="checkbox_addveh<?php echo $i; ?>" <?php if ($vehicle_feature[$i]->check) echo "checked"; ?> name="feature[<?php echo $i; ?>]" value="<?php echo $vehicle_feature[$i]->id; ?>">

The checkboxes that aren't checked are never submitted. The boxes that are checked get submitted, but they get numbered consecutively from 0, and won't have the same indexes as the other corresponding input fields.

JQuery Find #ID, RemoveClass and AddClass

jQuery('#testID2').find('.test2').replaceWith('.test3');

Semantically, you are selecting the element with the ID testID2, then you are looking for any descendent elements with the class test2 (does not exist) and then you are replacing that element with another element (elements anywhere in the page with the class test3) that also do not exist.

You need to do this:

jQuery('#testID2').addClass('test3').removeClass('test2');

This selects the element with the ID testID2, then adds the class test3 to it. Last, it removes the class test2 from that element.

std::thread calling method of class

Not so hard:

#include <thread>

void Test::runMultiThread()
{
    std::thread t1(&Test::calculate, this,  0, 10);
    std::thread t2(&Test::calculate, this, 11, 20);
    t1.join();
    t2.join();
}

If the result of the computation is still needed, use a future instead:

#include <future>

void Test::runMultiThread()
{
     auto f1 = std::async(&Test::calculate, this,  0, 10);
     auto f2 = std::async(&Test::calculate, this, 11, 20);

     auto res1 = f1.get();
     auto res2 = f2.get();
}

image.onload event and browser cache

I have met the same issue today. After trying various method, I realize that just put the code of sizing inside $(window).load(function() {}) instead of document.ready would solve part of issue (if you are not ajaxing the page).

Delete worksheet in Excel using VBA

Consider:

Sub SheetKiller()
    Dim s As Worksheet, t As String
    Dim i As Long, K As Long
    K = Sheets.Count

    For i = K To 1 Step -1
        t = Sheets(i).Name
        If t = "ID Sheet" Or t = "Summary" Then
            Application.DisplayAlerts = False
                Sheets(i).Delete
            Application.DisplayAlerts = True
        End If
    Next i
End Sub

NOTE:

Because we are deleting, we run the loop backwards.

How do you change library location in R?

I've used this successfully inside R script:

library("reshape2",lib.loc="/path/to/R-packages/")

useful if for whatever reason libraries are in more than one place.

Easy way of running the same junit test over and over?

You could run your JUnit test from a main method and repeat it so many times you need:

package tests;

import static org.junit.Assert.*;

import org.junit.Test;
import org.junit.runner.Result;

public class RepeatedTest {

    @Test
    public void test() {
        fail("Not yet implemented");
    }

    public static void main(String args[]) {

        boolean runForever = true;

        while (runForever) {
            Result result = org.junit.runner.JUnitCore.runClasses(RepeatedTest.class);

            if (result.getFailureCount() > 0) {
                runForever = false;
               //Do something with the result object

            }
        }

    }

}

How to run a cronjob every X minutes?

You are setting your cron to run on 10th minute in every hour.
To set it to every 5 mins change to */5 * * * * /usr/bin/php /mydomain.in/cronmail.php > /dev/null 2>&1

Globally catch exceptions in a WPF application?

Use the Application.DispatcherUnhandledException Event. See this question for a summary (see Drew Noakes' answer).

Be aware that there'll be still exceptions which preclude a successful resuming of your application, like after a stack overflow, exhausted memory, or lost network connectivity while you're trying to save to the database.

Wait until an HTML5 video loads

call function on load:

<video onload="doWhatYouNeedTo()" src="demo.mp4" id="video">

get video duration

var video = document.getElementById("video");
var duration = video.duration;

jQuery equivalent of JavaScript's addEventListener method

One thing to note is that jQuery event methods do not fire/trap load on embed tags that contain SVG DOM which loads as a separate document in the embed tag. The only way I found to trap a load event on these were to use raw JavaScript.

This will not work (I've tried on/bind/load methods):

$img.on('load', function () {
    console.log('FOO!');
});

However, this works:

$img[0].addEventListener('load', function () {
    console.log('FOO!');
}, false);

C++ "was not declared in this scope" compile error

As the compiler says, grid was not declared in the scope of your function :) "Scope" basically means a set of curly braces. Every variable is limited to the scope in which it is declared (it cannot be accessed outside that scope). In your case, you're declaring the grid variable in your main() function and trying to use it in nonrecursivecountcells(). You seem to be passing it as the argument colors however, so I suggest you just rename your uses of grid in nonrecursivecountcells() to colors. I think there may be something wrong with trying to pass the array that way, too, so you should probably investigate passing it as a pointer (unless someone else says something to the contrary).

How to print variables in Perl

print "Number of lines: $nids\n";
print "Content: $ids\n";

How did Perl complain? print $ids should work, though you probably want a newline at the end, either explicitly with print as above or implicitly by using say or -l/$\.

If you want to interpolate a variable in a string and have something immediately after it that would looks like part of the variable but isn't, enclose the variable name in {}:

print "foo${ids}bar";

The name does not exist in the namespace error in XAML

Adding to the pile.

Mine was the assembly name of the WPF application was the same assembly name as a referenced dll. So make sure you don't have duplicate assembly names in any of your projects.

Difference between malloc and calloc?

calloc() gives you a zero-initialized buffer, while malloc() leaves the memory uninitialized.

For large allocations, most calloc implementations under mainstream OSes will get known-zeroed pages from the OS (e.g. via POSIX mmap(MAP_ANONYMOUS) or Windows VirtualAlloc) so it doesn't need to write them in user-space. This is how normal malloc gets more pages from the OS as well; calloc just takes advantage of the OS's guarantee.

This means calloc memory can still be "clean" and lazily-allocated, and copy-on-write mapped to a system-wide shared physical page of zeros. (Assuming a system with virtual memory.)

Some compilers even can optimize malloc + memset(0) into calloc for you, but you should use calloc explicitly if you want the memory to read as 0.

If you aren't going to ever read memory before writing it, use malloc so it can (potentially) give you dirty memory from its internal free list instead of getting new pages from the OS. (Or instead of zeroing a block of memory on the free list for a small allocation).

Embedded implementations of calloc may leave it up to calloc itself to zero memory if there's no OS, or it's not a fancy multi-user OS that zeros pages to stop information leaks between processes.

On embedded Linux, malloc could mmap(MAP_UNINITIALIZED|MAP_ANONYMOUS), which is only enabled for some embedded kernels because it's insecure on a multi-user system.

Setting onSubmit in React.js

<form onSubmit={(e) => {this.doSomething(); e.preventDefault();}}></form>

it work fine for me

Delete all documents from index/type without deleting type

Elasticsearch 2.3 the option

    action.destructive_requires_name: true

in elasticsearch.yml do the trip

    curl -XDELETE http://localhost:9200/twitter/tweet

How do I create a view controller file after creating a new view controller?

Correct, when you drag a view controller object onto your storyboard in order to create a new scene, it doesn't automatically make the new class for you, too.

Having added a new view controller scene to your storyboard, you then have to:

Create a UIViewController subclass. For example, go to your target's folder in the project navigator panel on the left and then control-click and choose "New File...". Choose a "Cocoa Touch Class":

And then select a unique name for the new view controller subclass:
Specify this new subclass as the base class for the scene you just added to the storyboard.
Now hook up any IBOutlet and IBAction references for this new scene with the new view controller subclass.

How do function pointers in C work?

Function pointers in C can be used to perform object-oriented programming in C.

For example, the following lines is written in C:

String s1 = newString();
s1->set(s1, "hello");

Yes, the -> and the lack of a new operator is a dead give away, but it sure seems to imply that we're setting the text of some String class to be "hello".

By using function pointers, it is possible to emulate methods in C.

How is this accomplished?

The String class is actually a struct with a bunch of function pointers which act as a way to simulate methods. The following is a partial declaration of the String class:

typedef struct String_Struct* String;

struct String_Struct
{
    char* (*get)(const void* self);
    void (*set)(const void* self, char* value);
    int (*length)(const void* self);
};

char* getString(const void* self);
void setString(const void* self, char* value);
int lengthString(const void* self);

String newString();

As can be seen, the methods of the String class are actually function pointers to the declared function. In preparing the instance of the String, the newString function is called in order to set up the function pointers to their respective functions:

String newString()
{
    String self = (String)malloc(sizeof(struct String_Struct));

    self->get = &getString;
    self->set = &setString;
    self->length = &lengthString;

    self->set(self, "");

    return self;
}

For example, the getString function that is called by invoking the get method is defined as the following:

char* getString(const void* self_obj)
{
    return ((String)self_obj)->internal->value;
}

One thing that can be noticed is that there is no concept of an instance of an object and having methods that are actually a part of an object, so a "self object" must be passed in on each invocation. (And the internal is just a hidden struct which was omitted from the code listing earlier -- it is a way of performing information hiding, but that is not relevant to function pointers.)

So, rather than being able to do s1->set("hello");, one must pass in the object to perform the action on s1->set(s1, "hello").

With that minor explanation having to pass in a reference to yourself out of the way, we'll move to the next part, which is inheritance in C.

Let's say we want to make a subclass of String, say an ImmutableString. In order to make the string immutable, the set method will not be accessible, while maintaining access to get and length, and force the "constructor" to accept a char*:

typedef struct ImmutableString_Struct* ImmutableString;

struct ImmutableString_Struct
{
    String base;

    char* (*get)(const void* self);
    int (*length)(const void* self);
};

ImmutableString newImmutableString(const char* value);

Basically, for all subclasses, the available methods are once again function pointers. This time, the declaration for the set method is not present, therefore, it cannot be called in a ImmutableString.

As for the implementation of the ImmutableString, the only relevant code is the "constructor" function, the newImmutableString:

ImmutableString newImmutableString(const char* value)
{
    ImmutableString self = (ImmutableString)malloc(sizeof(struct ImmutableString_Struct));

    self->base = newString();

    self->get = self->base->get;
    self->length = self->base->length;

    self->base->set(self->base, (char*)value);

    return self;
}

In instantiating the ImmutableString, the function pointers to the get and length methods actually refer to the String.get and String.length method, by going through the base variable which is an internally stored String object.

The use of a function pointer can achieve inheritance of a method from a superclass.

We can further continue to polymorphism in C.

If for example we wanted to change the behavior of the length method to return 0 all the time in the ImmutableString class for some reason, all that would have to be done is to:

Add a function that is going to serve as the overriding length method.
Go to the "constructor" and set the function pointer to the overriding length method.

Adding an overriding length method in ImmutableString may be performed by adding an lengthOverrideMethod:

int lengthOverrideMethod(const void* self)
{
    return 0;
}

Then, the function pointer for the length method in the constructor is hooked up to the lengthOverrideMethod:

ImmutableString newImmutableString(const char* value)
{
    ImmutableString self = (ImmutableString)malloc(sizeof(struct ImmutableString_Struct));

    self->base = newString();

    self->get = self->base->get;
    self->length = &lengthOverrideMethod;

    self->base->set(self->base, (char*)value);

    return self;
}

Now, rather than having an identical behavior for the length method in ImmutableString class as the String class, now the length method will refer to the behavior defined in the lengthOverrideMethod function.

I must add a disclaimer that I am still learning how to write with an object-oriented programming style in C, so there probably are points that I didn't explain well, or may just be off mark in terms of how best to implement OOP in C. But my purpose was to try to illustrate one of many uses of function pointers.

For more information on how to perform object-oriented programming in C, please refer to the following questions:

How do I update Anaconda?

On Mac, open a terminal and run the following two commands.

conda update conda
conda update anaconda

Make sure to run each command multiple times to update to the current version.

Which font is used in Visual Studio Code Editor and how to change fonts?

In the default settings, VS Code uses the following fonts (14 pt) in descending order:

Monaco
Menlo
Consolas
"Droid Sans Mono"
"Inconsolata"
"Courier New"
monospace (fallback)

How to verify: VS Code runs in a browser. In the first version, you could hit F12 to open the Developer Tools. Inspecting the DOM, you can find a containing several s that make up that line of code. Inspecting one of those spans, you can see that font-family is just the list above.

How can I protect my .NET assemblies from decompilation?

Host your service in any cloud service provider.

How to store a dataframe using Pandas

Although there are already some answers I found a nice comparison in which they tried several ways to serialize Pandas DataFrames: Efficiently Store Pandas DataFrames.

They compare:

pickle: original ASCII data format
cPickle, a C library
pickle-p2: uses the newer binary format
json: standardlib json library
json-no-index: like json, but without index
msgpack: binary JSON alternative
CSV
hdfstore: HDF5 storage format

In their experiment, they serialize a DataFrame of 1,000,000 rows with the two columns tested separately: one with text data, the other with numbers. Their disclaimer says:

You should not trust that what follows generalizes to your data. You should look at your own data and run benchmarks yourself

The source code for the test which they refer to is available online. Since this code did not work directly I made some minor changes, which you can get here: serialize.py I got the following results:

They also mention that with the conversion of text data to categorical data the serialization is much faster. In their test about 10 times as fast (also see the test code).

Edit: The higher times for pickle than CSV can be explained by the data format used. By default pickle uses a printable ASCII representation, which generates larger data sets. As can be seen from the graph however, pickle using the newer binary data format (version 2, pickle-p2) has much lower load times.

Some other references:

In the question Fastest Python library to read a CSV file there is a very detailed answer which compares different libraries to read csv files with a benchmark. The result is that for reading csv files numpy.fromfile is the fastest.
Another serialization test shows msgpack, ujson, and cPickle to be the quickest in serializing.

Create a .tar.bz2 file Linux

Try this from different folder:

sudo tar -cvjSf folder.tar.bz2 folder/*

Checking if a folder exists (and creating folders) in Qt, C++

When you use QDir.mkpath() it returns true if the path already exists, in the other hand QDir.mkdir() returns false if the path already exists. So depending on your program you have to choose which fits better.

You can see more on Qt Documentation

bootstrap datepicker change date event doesnt fire up when manually editing dates or clearing date

I have this version about datetimepicker https://tempusdominus.github.io/bootstrap-4/ and for any reason doesn`t work the change event with jquery but with JS vanilla it does

I figure out like this

document.getElementById('date').onchange = function(){ ...the jquery code...}

I hope work for you

How to change my Git username in terminal?

You probably need to update the remote URL since github puts your username in it. You can take a look at the original URL by typing

git config --get remote.origin.url

Or just go to the repository page on Github and get the new URL. Then use

git remote set-url origin https://{new url with username replaced}

to update the URL with your new username.

Java Regex Replace with Capturing Group

earl's answer gives you the solution, but I thought I'd add what the problem is that's causing your IllegalStateException. You're calling group(1) without having first called a matching operation (such as find()). This isn't needed if you're just using $1 since the replaceAll() is the matching operation.

Programs & Examples On #Intense debate

How to make a whole 'div' clickable in html and css without JavaScript?

Jaxb, Class has two properties of the same name

Android: resizing imageview in XML

XML Serialize generic list of serializable objects

How can I know if a branch has been already merged into master?

Asynchronously load images with jQuery

How to make child divs always fit inside parent div?

How can I capture the result of var_dump to a string?

What Content-Type value should I send for my XML sitemap?

"Parser Error Message: Could not load type" in Global.asax

Get current time as formatted string in Go?

How to save the contents of a div as a image?

List Highest Correlation Pairs from a Large Correlation Matrix in Pandas?

internet explorer 10 - how to apply grayscale filter?

Show/hide image with JavaScript

How to square all the values in a vector in R?

Regular expression to match numbers with or without commas and decimals in text

Simpler way to create dictionary of separate variables?

How to resolve : Can not find the tag library descriptor for "http://java.sun.com/jsp/jstl/core"

Could not autowire field in spring. why?

Convert blob URL to normal URL

How do I allow HTTPS for Apache on localhost?

mySQL convert varchar to date

How to pass all arguments passed to my bash script to a function of mine?

django MultiValueDictKeyError error, how do I deal with it

Javascript Image Resize

What is the difference between SQL, PL-SQL and T-SQL?

Is there a way to pass javascript variables in url?

How can I run specific migration in laravel

GROUP BY with MAX(DATE)

How to split a string in Ruby and get all items except the first one?

Warning: date_format() expects parameter 1 to be DateTime

how to create Socket connection in Android?

Python: avoid new line with print command

Setting up MySQL and importing dump within Dockerfile

Solution 1: use a one-line RUN

Solution 2: use a script

Git On Custom SSH Port

MySql: is it possible to 'SUM IF' or to 'COUNT IF'?

How to get a variable value if variable name is stored as string?

How do I parse a string to a float or int?

C++ wait for user input

Which method performs better: .Any() vs .Count() > 0?

Case-insensitive string comparison in C++

How to add title to seaborn boxplot

How to make a promise from setTimeout

Why do you need to put #!/bin/bash at the beginning of a script file?

No connection could be made because the target machine actively refused it?

Default keystore file does not exist?

Getting one value from a tuple

Adding elements to object

Importing Excel into a DataTable Quickly

Leaflet changing Marker color

How can multiple rows be concatenated into one in Oracle without creating a stored procedure?

How to update column value in laravel

Can I change the height of an image in CSS :before/:after pseudo-elements?

Using ng-if as a switch inside ng-repeat?

DateTime format to SQL format using C#

VirtualBox: mount.vboxsf: mounting failed with the error: No such device

Chrome - ERR_CACHE_MISS

How might I force a floating DIV to match the height of another floating DIV?

How to write a simple Html.DropDownListFor()?

Folder structure for a Node.js project

SELECT using 'CASE' in SQL

Can't escape the backslash with regex?

Constants in Kotlin -- what's a recommended way to create them?

jquery variable syntax

Testing pointers for validity (C/C++)

How to convert a Java String to an ASCII byte array?

IntelliJ does not show 'Class' when we right click and select 'New'

Best way to "push" into C# array

"unadd" a file to svn before commit

How to construct a REST API that takes an array of id's for the resources

UNC path to a folder on my local computer

In excel how do I reference the current row but a specific column?

How to disable and then enable onclick event on <div> with javascript

How to find an available port?

Best practice for using assert?

Running Facebook application on localhost

Solution 1: use a one-line `RUN`