Programs & Examples On #Readwritelock

ReadWriteLock is a structure of the two locks. From these, one locks for reading (multiple threads can access, none can modify) and another for write access (only one thread can access and also modify at time).

What is base 64 encoding used for?

When you have some binary data that you want to ship across a network, you generally don't do it by just streaming the bits and bytes over the wire in a raw format. Why? because some media are made for streaming text. You never know -- some protocols may interpret your binary data as control characters (like a modem), or your binary data could be screwed up because the underlying protocol might think that you've entered a special character combination (like how FTP translates line endings).

So to get around this, people encode the binary data into characters. Base64 is one of these types of encodings.

Why 64?
Because you can generally rely on the same 64 characters being present in many character sets, and you can be reasonably confident that your data's going to end up on the other side of the wire uncorrupted.

What are carriage return, linefeed, and form feed?

\r is carriage return and moves the cursor back like if i will do-

printf("stackoverflow\rnine")
ninekoverflow

means it has shifted the cursor to the beginning of "stackoverflow" and overwrites the starting four characters since "nine" is four character long.

\n is new line character which changes the line and takes the cursor to the beginning of a new line like-

printf("stackoverflow\nnine")
stackoverflow
nine

\f is form feed, its use has become obsolete but it is used for giving indentation like

printf("stackoverflow\fnine")
stackoverflow
             nine

if i will write like-

printf("stackoverflow\fnine\fgreat")
stackoverflow
             nine
                 great

Exploitable PHP functions

i'd particularly want to add unserialize() to this list. It has had a long history of various vulnerabilities including arbitrary code execution, denial of service and memory information leakage. It should never be called on user-supplied data. Many of these vuls have been fixed in releases over the last dew years, but it still retains a couple of nasty vuls at the current time of writing.

For other information about dodgy php functions/usage look around the Hardened PHP Project and its advisories. Also the recent Month of PHP Security and 2007's Month of PHP Bugs projects

Also note that, by design, unserializing an object will cause the constructor and destructor functions to execute; another reason not to call it on user-supplied data.

Convert a JSON string to object in Java ME?

I've written a library that uses json.org to parse JSON, but it will actually create a proxy of an interface for you. The code/JAR is on code.google.com.

http://fixjures.googlecode.com/

I don't know if it works on J2ME. Since it uses Java Reflection to create proxies, I'm thinking it won't work. Also, it's currently got a hard dependency on Google Collections which I want to remove and it's probably too heavyweight for your needs, but it allows you to interact with your JSON data in the way you're looking for:

interface Foo {
    String getName();
    int getWidth();
    int getHeight();
}

Foo myFoo = Fixjure.of(Foo.class).from(JSONSource.newJsonString("{ name : \"foo name\" }")).create();
String name = myFoo.getName(); // name now .equals("foo name");

Bulk Insert Correctly Quoted CSV File in SQL Server

I had this same problem, and I didn't want to have to go the SSIS route, so I found a PowerShell script that is easy to run and handles the case of the quotes with the comma in that particular field:

Source Code and DLL for the PowerShell Script: https://github.com/billgraziano/CsvDataReader

Here's a blog that explains the usage: http://www.sqlteam.com/article/fast-csv-import-in-powershell-to-sql-server

javascript - pass selected value from popup window to parent window input box

From your code

<input type=button value="Select" onClick="sendValue(this.form.details);"

Im not sure that your this.form.details valid or not.

IF it's valid, have a look in window.opener.document.getElementById('details').value = selvalue;

I can't found an input's id contain details I'm just found only id=sku1 (recommend you to add " like id="sku1").

And from your id it's hardcode. Let's see how to do with dynamic when a child has callback to update some textbox on the parent Take a look at here.

First page.

<html>
<head>
<script>
    function callFromDialog(id,data){ //for callback from the dialog
        document.getElementById(id).value = data;
        // do some thing other if you want
    }

    function choose(id){
        var URL = "secondPage.html?id=" + id + "&dummy=avoid#";
        window.open(URL,"mywindow","menubar=1,resizable=1,width=350,height=250")
    }
</script>
</head>
<body>
<input id="tbFirst" type="text" /> <button onclick="choose('tbFirst')">choose</button>
<input id="tbSecond" type="text" /> <button onclick="choose('tbSecond')">choose</button>
</body>
</html>

Look in function choose I'm sent an id of textbox to the popup window (don't forget to add dummy data at last of URL param like &dummy=avoid#)

Popup Page

<html>
<head>
<script>
    function goSelect(data){
        var idFromCallPage = getUrlVars()["id"];
        window.opener.callFromDialog(idFromCallPage,data); //or use //window.opener.document.getElementById(idFromCallPage).value = data;
        window.close();
    }


    function getUrlVars(){
        var vars = [], hash;
        var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
        for(var i = 0; i < hashes.length; i++)
        {
            hash = hashes[i].split('=');
            vars.push(hash[0]);
            vars[hash[0]] = hash[1];
        }
        return vars;
    }
</script>
</head>
<body>
<a href="#" onclick="goSelect('Car')">Car</a> <br />
<a href="#" onclick="goSelect('Food')">Food</a> <br />
</body>
</html>

I have add function getUrlVars for get URL param that the parent has pass to child.

Okay, when select data in the popup, for this case it's will call function goSelect

In that function will get URL param to sent back.

And when you need to sent back to the parent just use window.opener and the name of function like window.opener.callFromDialog

By fully is window.opener.callFromDialog(idFromCallPage,data);

Or if you want to use window.opener.document.getElementById(idFromCallPage).value = data; It's ok too.

Use dynamic variable names in JavaScript

You can use the window object to get at it .

window['myVar']

window has a reference to all global variables and global functions you are using.

IIS error, Unable to start debugging on the webserver

Just ran into this problem myself and it turned out to be that my site in IIS was set up to use anonymous authentication with a specific network account. I had been forced to reset the password on that account, and so IIS was failing because it was using the old one. Once I updated the site with the new password (or even better, changed it to use Network Service instead), all worked again.

Checking if a SQL Server login already exists

This is for Azure SQL:

IF (EXISTS(SELECT TOP 1 1 FROM sys.sql_logins WHERE [name] = '<login>'))
    DROP LOGIN [<login>];

Source: How to check whether database user already exists in Azure SQL Database

Styling JQuery UI Autocomplete

Are you looking for this selector?:

.ui-menu .ui-menu-item a{
    background:red;
    height:10px;
    font-size:8px;
}

Ugly demo:

http://jsfiddle.net/zeSTc/

Just replace with your code:

.ui-menu .ui-menu-item a{
    color: #96f226;
    border-radius: 0px;
    border: 1px solid #454545;
}

demo: http://jsfiddle.net/w5Dt2/

Python sum() function with list parameter

numbers = [1, 2, 3]
numsum = sum(list(numbers))
print(numsum)

This would work, if your are trying to Sum up a list.

Brew doctor says: "Warning: /usr/local/include isn't writable."

What worked for me was too

sudo chmod g+w /usr/local
sudo chgrp staff /usr/local

HTML5 textarea placeholder not appearing

use <textarea></textarea> instead of leaving a space between the opening and closing tags as <textarea> </textarea>

Laravel 4: how to run a raw SQL?

Actually, Laravel 4 does have a table rename function in Illuminate/Database/Schema/Builder.php, it's just undocumented at the moment: Schema::rename($from, $to);.

How do I kill background processes / jobs when my shell script exits?

jobs -p does not work in all shells if called in a sub-shell, possibly unless its output is redirected into a file but not a pipe. (I assume it was originally intended for interactive use only.)

What about the following:

trap 'while kill %% 2>/dev/null; do jobs > /dev/null; done' INT TERM EXIT [...]

The call to "jobs" is needed with Debian's dash shell, which fails to update the current job ("%%") if it is missing.

How to Pass Parameters to Activator.CreateInstance<T>()

There is another way to pass arguments to CreateInstance through named parameters.

Based on that, you can pass a array towards CreateInstance. This will allow you to have 0 or multiple arguments.

public T CreateInstance<T>(params object[] paramArray)
{
  return (T)Activator.CreateInstance(typeof(T), args:paramArray);
}

A quick and easy way to join array elements with a separator (the opposite of split) in Java

Using Java 8 you can do this in a very clean way:

String.join(delimiter, elements);

This works in three ways:

1) directly specifying the elements

String joined1 = String.join(",", "a", "b", "c");

2) using arrays

String[] array = new String[] { "a", "b", "c" };
String joined2 = String.join(",", array);

3) using iterables

List<String> list = Arrays.asList(array);
String joined3 = String.join(",", list);

Get to UIViewController from UIView?

Swift 4

(more concise than the other answers)

fileprivate extension UIView {

  var firstViewController: UIViewController? {
    let firstViewController = sequence(first: self, next: { $0.next }).first(where: { $0 is UIViewController })
    return firstViewController as? UIViewController
  }

}

My use case for which I need to access the view first UIViewController: I have an object that wraps around AVPlayer / AVPlayerViewController and I want to provide a simple show(in view: UIView) method that will embed AVPlayerViewController into view. For that, I need to access view's UIViewController.

How to use ng-if to test if a variable is defined

You can still use angular.isDefined()

You just need to set

$rootScope.angular = angular;

in the "run" phase.

See update plunkr: http://plnkr.co/edit/h4ET5dJt3e12MUAXy1mS?p=preview

How to convert string to integer in C#

int myInt = System.Convert.ToInt32(myString);

As several others have mentioned, you can also use int.Parse() and int.TryParse().

If you're certain that the string will always be an int:

int myInt = int.Parse(myString);

If you'd like to check whether string is really an int first:

int myInt;
bool isValid = int.TryParse(myString, out myInt); // the out keyword allows the method to essentially "return" a second value
if (isValid)
{
    int plusOne = myInt + 1;
}

Getting SyntaxError for print with keyword argument end=' '

I think he's using Python 3.0 and you're using Python 2.6.

set the width of select2 input (through Angular-ui directive)

On a recent project built using Bootstrap 4, I had tried all of the above methods but nothing worked. My approach was by editing the library CSS using jQuery to get 100% on the table.

 // * Select2 4.0.7

$('.select2-multiple').select2({
    // theme: 'bootstrap4', //Doesn't work
    // width:'100%', //Doesn't work
    width: 'resolve'
});

//The Fix
$('.select2-w-100').parent().find('span')
    .removeClass('select2-container')
    .css("width", "100%")
    .css("flex-grow", "1")
    .css("box-sizing", "border-box")
    .css("display", "inline-block")
    .css("margin", "0")
    .css("position", "relative")
    .css("vertical-align", "middle")

Working Demo

_x000D_
_x000D_
$('.select2-multiple').select2({_x000D_
        // theme: 'bootstrap4', //Doesn't work_x000D_
        // width:'100%',//Doens't work_x000D_
        width: 'resolve'_x000D_
    });_x000D_
    //Fix the above style width:100%_x000D_
    $('.select2-w-100').parent().find('span')_x000D_
        .removeClass('select2-container')_x000D_
        .css("width", "100%")_x000D_
        .css("flex-grow", "1")_x000D_
        .css("box-sizing", "border-box")_x000D_
        .css("display", "inline-block")_x000D_
        .css("margin", "0")_x000D_
        .css("position", "relative")_x000D_
        .css("vertical-align", "middle")
_x000D_
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" rel="stylesheet"/>_x000D_
<link href="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.7/css/select2.min.css" rel="stylesheet" />_x000D_
_x000D_
<div class="table-responsive">_x000D_
    <table class="table">_x000D_
        <thead>_x000D_
        <tr>_x000D_
            <th scope="col" class="w-50">#</th>_x000D_
            <th scope="col" class="w-50">Trade Zones</th>_x000D_
        </tr>_x000D_
        </thead>_x000D_
        <tbody>_x000D_
        <tr>_x000D_
            <td>_x000D_
                1_x000D_
            </td>_x000D_
            <td>_x000D_
                <select class="form-control select2-multiple select2-w-100" name="sellingFees[]"_x000D_
                        multiple="multiple">_x000D_
                    <option value="1">One</option>_x000D_
                    <option value="1">Two</option>_x000D_
                    <option value="1">Three</option>_x000D_
                    <option value="1">Okay</option>_x000D_
                </select>_x000D_
            </td>_x000D_
        </tr>_x000D_
        </tbody>_x000D_
    </table>_x000D_
</div>_x000D_
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.7/js/select2.min.js"></script>
_x000D_
_x000D_
_x000D_

Bloomberg BDH function with ISIN

The problem is that an isin does not identify the exchange, only an issuer.

Let's say your isin is US4592001014 (IBM), one way to do it would be:

  • get the ticker (in A1):

    =BDP("US4592001014 ISIN", "TICKER") => IBM
    
  • get a proper symbol (in A2)

    =BDP("US4592001014 ISIN", "PARSEKYABLE_DES") => IBM XX Equity
    

    where XX depends on your terminal settings, which you can check on CNDF <Go>.

  • get the main exchange composite ticker, or whatever suits your need (in A3):

    =BDP(A2,"EQY_PRIM_SECURITY_COMP_EXCH") => US
    
  • and finally:

    =BDP(A1&" "&A3&" Equity", "LAST_PRICE") => the last price of IBM US Equity
    

How to find the path of the local git repository when I am possibly in a subdirectory

git rev-parse --show-toplevel

could be enough if executed within a git repo.
From git rev-parse man page:

--show-toplevel

Show the absolute path of the top-level directory.

For older versions (before 1.7.x), the other options are listed in "Is there a way to get the git root directory in one command?":

git rev-parse --git-dir

That would give the path of the .git directory.


The OP mentions:

git rev-parse --show-prefix

which returns the local path under the git repo root. (empty if you are at the git repo root)


Note: for simply checking if one is in a git repo, I find the following command quite expressive:

git rev-parse --is-inside-work-tree

And yes, if you need to check if you are in a .git git-dir folder:

git rev-parse --is-inside-git-dir

Pandas rename column by position?

try this

df.rename(columns={ df.columns[1]: "your value" }, inplace = True)

maven... Failed to clean project: Failed to delete ..\org.ow2.util.asm-asm-tree-3.1.jar

Try disabling Project->Build Automatically.

As Scorpio suggested, there's a process running that's got a lock on a file somewhere.

I have a large multi-module maven project that regularly fails on clean and this resolves it for me. I re-enable Build Automatically when I'm done.

how to overcome ERROR 1045 (28000): Access denied for user 'ODBC'@'localhost' (using password: NO) permanently

Why you can't just use mysqlsh?

PS C:\Users\artur\Desktop> mysqlsh --user root
MySQL Shell 8.0.17

Copyright (c) 2016, 2019, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its affiliates.
Other names may be trademarks of their respective owners.

Type '\help' or '\?' for help; '\quit' to exit.
Creating a session to 'root@localhost'
Fetching schema names for autocompletion... Press ^C to stop.
Your MySQL connection id is 13 (X protocol)
Server version: 8.0.17 MySQL Community Server - GPL
No default schema selected; type \use <schema> to set one.
 MySQL  localhost:33060+ ssl  JS >

mysqlsh on windows terminal (pic)

Verify ImageMagick installation

In bash:

$ convert -version

or

$ /usr/local/bin/convert -version

No need to write any PHP file just to check.

IF - ELSE IF - ELSE Structure in Excel

When FIND returns #VALUE!, it is an error, not a string, so you can't compare FIND(...) with "#VALUE!", you need to check if FIND returns an error with ISERROR. Also FIND can work on multiple characters.

So a simplified and working version of your formula would be:

=IF(ISERROR(FIND("abc",A1))=FALSE, "Green", IF(ISERROR(FIND("xyz",A1))=FALSE, "Yellow", "Red"))

Or, to remove the double negations:

=IF(ISERROR(FIND("abc",A1)), IF(ISERROR(FIND("xyz",A1)), "Red", "Yellow"),"Green")

Ruby on Rails: How do I add placeholder text to a f.text_field?

With rails >= 3.0, you can simply use the placeholder option.

f.text_field :attr, placeholder: "placeholder text"

How to print bytes in hexadecimal using System.out.println?

for (int j=0; j<test.length; j++) {
   System.out.format("%02X ", test[j]);
}
System.out.println();

Ignore files that have already been committed to a Git repository

Yes - .gitignore system only ignores files not currently under version control from git.

I.e. if you've already added a file called test.txt using git-add, then adding test.txt to .gitignore will still cause changes to test.txt to be tracked.

You would have to git rm test.txt first and commit that change. Only then will changes to test.txt be ignored.

"Multiple definition", "first defined here" errors

The problem here is that you are including commands.c in commands.h before the function prototype. Therefore, the C pre-processor inserts the content of commands.c into commands.h before the function prototype. commands.c contains the function definition. As a result, the function definition ends up before than the function declaration causing the error.

The content of commands.h after the pre-processor phase looks like this:

#ifndef COMMANDS_H_
#define COMMANDS_H_

// function definition
void f123(){

}

// function declaration
void f123();

#endif /* COMMANDS_H_ */

This is an error because you can't declare a function after its definition in C. If you swapped #include "commands.c" and the function declaration the error shouldn't happen because, now, the function prototype comes before the function declaration.

However, including a .c file is a bad practice and should be avoided. A better solution for this problem would be to include commands.h in commands.c and link the compiled version of command to the main file. For example:

commands.h

#ifndef COMMANDS_H_
#define COMMANDS_H_

void f123(); // function declaration

#endif

commands.c

#include "commands.h"

void f123(){} // function definition

Postgresql GROUP_CONCAT equivalent?

Hope below Oracle query will work.

Select First_column,LISTAGG(second_column,',') 
    WITHIN GROUP (ORDER BY second_column) as Sec_column, 
    LISTAGG(third_column,',') 
    WITHIN GROUP (ORDER BY second_column) as thrd_column 
FROM tablename 
GROUP BY first_column

Notification bar icon turns white in Android 5 Lollipop

According to the Android design guidelines you must use a silhouette for builder.setSmallIcon(R.drawable.some_notification_icon); But if you still wants to show a colorful icon as a notification icon here is the trick for lollipop and above use below code. The largeIcon will act as a primary notification icon and you also need to provide a silhouette for smallIcon as it will be shown over the bottom right of the largeIcon.

if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)
{
     builder.setColor(context.getResources().getColor(R.color.red));
     builder.setSmallIcon(R.drawable.some_notification_icon);
     builder.setLargeIcon(BitmapFactory.decodeResource(context.getResources(), R.mipmap.ic_launcher));
}

And pre-lollipop use only .setSmallIcon(R.mipmap.ic_launcher) with your builder.

Remove spacing between table cells and rows

Nothing has worked. The solution for the issue is.

<style>
table td {
    padding: 0;
}
</style>

Convert JS date time to MySQL datetime

var _t = new Date();

if you want UTC format simply

_t.toLocaleString('indian', { timeZone: 'UTC' }).replace(/(\w+)\/(\w+)\/(\w+), (\w+)/, '$3-$2-$1 $4');

or

_t.toISOString().slice(0, 19).replace('T', ' ');

and if want in specific timezone then

_t.toLocaleString('indian', { timeZone: 'asia/kolkata' }).replace(/(\w+)\/(\w+)\/(\w+), (\w+)/, '$3-$2-$1 $4');

Center text in div?

HTML

<div class="outside">
  <div class="inside">
      <p>Centered Text</p>
  </div>
</div>

CSS

.outside { 
  position: absolute; 
  display: table; 
}

.inside {
  display: table-cell; 
  vertical-align: middle; 
  text-align: center; 
}

Querying Windows Active Directory server using ldapsearch from command line

You could query an LDAP server from the command line with ldap-utils: ldapsearch, ldapadd, ldapmodify

Java Programming: call an exe from Java and passing parameters

Pass your arguments in constructor itself.

Process process = new ProcessBuilder("C:\\PathToExe\\MyExe.exe","param1","param2").start();

Best practices for circular shift (rotate) operations in C++

Source Code x bit number

int x =8;
data =15; //input
unsigned char tmp;
for(int i =0;i<x;i++)
{
printf("Data & 1    %d\n",data&1);
printf("Data Shifted value %d\n",data>>1^(data&1)<<(x-1));
tmp = data>>1|(data&1)<<(x-1);
data = tmp;  
}

problem with php mail 'From' header

The web host is not really playing foul. It's not strictly according to the rules - but compared with some some of the amazing inventions intended to prevent spam, its not a particularly bad one.

If you really do want to send mail from '@gmail.com' why not just use the gmail SMTP service? If you can't reconfigure the server where PHP is running, then there are lots of email wrapper tools out there which allow you to specify a custom SMTP relay phpmailer springs to mind.

C.

Difference between array_map, array_walk and array_filter

The other answers demonstrate the difference between array_walk (in-place modification) and array_map (return modified copy) quite well. However, they don't really mention array_reduce, which is an illuminating way to understand array_map and array_filter.

The array_reduce function takes an array, a two-argument function and an 'accumulator', like this:

array_reduce(array('a', 'b', 'c', 'd'),
             'my_function',
             $accumulator)

The array's elements are combined with the accumulator one at a time, using the given function. The result of the above call is the same as doing this:

my_function(
  my_function(
    my_function(
      my_function(
        $accumulator,
        'a'),
      'b'),
    'c'),
  'd')

If you prefer to think in terms of loops, it's like doing the following (I've actually used this as a fallback when array_reduce wasn't available):

function array_reduce($array, $function, $accumulator) {
  foreach ($array as $element) {
    $accumulator = $function($accumulator, $element);
  }
  return $accumulator;
}

This looping version makes it clear why I've called the third argument an 'accumulator': we can use it to accumulate results through each iteration.

So what does this have to do with array_map and array_filter? It turns out that they're both a particular kind of array_reduce. We can implement them like this:

array_map($function, $array)    === array_reduce($array, $MAP,    array())
array_filter($array, $function) === array_reduce($array, $FILTER, array())

Ignore the fact that array_map and array_filter take their arguments in a different order; that's just another quirk of PHP. The important point is that the right-hand-side is identical except for the functions I've called $MAP and $FILTER. So, what do they look like?

$MAP = function($accumulator, $element) {
  $accumulator[] = $function($element);
  return $accumulator;
};

$FILTER = function($accumulator, $element) {
  if ($function($element)) $accumulator[] = $element;
  return $accumulator;
};

As you can see, both functions take in the $accumulator and return it again. There are two differences in these functions:

  • $MAP will always append to $accumulator, but $FILTER will only do so if $function($element) is TRUE.
  • $FILTER appends the original element, but $MAP appends $function($element).

Note that this is far from useless trivia; we can use it to make our algorithms more efficient!

We can often see code like these two examples:

// Transform the valid inputs
array_map('transform', array_filter($inputs, 'valid'))

// Get all numeric IDs
array_filter(array_map('get_id', $inputs), 'is_numeric')

Using array_map and array_filter instead of loops makes these examples look quite nice. However, it can be very inefficient if $inputs is large, since the first call (map or filter) will traverse $inputs and build an intermediate array. This intermediate array is passed straight into the second call, which will traverse the whole thing again, then the intermediate array will need to be garbage collected.

We can get rid of this intermediate array by exploiting the fact that array_map and array_filter are both examples of array_reduce. By combining them, we only have to traverse $inputs once in each example:

// Transform valid inputs
array_reduce($inputs,
             function($accumulator, $element) {
               if (valid($element)) $accumulator[] = transform($element);
               return $accumulator;
             },
             array())

// Get all numeric IDs
array_reduce($inputs,
             function($accumulator, $element) {
               $id = get_id($element);
               if (is_numeric($id)) $accumulator[] = $id;
               return $accumulator;
             },
             array())

NOTE: My implementations of array_map and array_filter above won't behave exactly like PHP's, since my array_map can only handle one array at a time and my array_filter won't use "empty" as its default $function. Also, neither will preserve keys.

It's not difficult to make them behave like PHP's, but I felt that these complications would make the core idea harder to spot.

Rails 3.1 and Image Assets

In 3.1 you just get rid of the 'images' part of the path. So an image that lives in /assets/images/example.png will actually be accessible in a get request at this url - /assets/example.png

Because the assets/images folder gets generated along with a new 3.1 app, this is the convention that they probably want you to follow. I think that's where image_tag will look for it, but I haven't tested that yet.

Also, during the RailsConf keynote, I remember D2h saying the the public folder should not have much in it anymore, mostly just error pages and a favicon.

How do I bottom-align grid elements in bootstrap fluid layout

Well, I didn't like any of those answers, my solution of the same problem was to add this:<div>&nbsp;</div>. So in your scheme it would look like this (more or less), no style changes were necessary in my case:

-row-fluid-------------------------------------
+-span6----------+ +----span6----------+
|                | | +---div---+       |
| content        | | | & nbsp; |       |
| that           | | +---------+       |
| is tall        | | +-----div--------+|   
|                | | |short content   ||
|                | | +----------------+|
+----------------+ +-------------------+
-----------------------------------------------

How can I rename column in laravel using migration?

The above answer is great or if it will not hurt you, just rollback the migration and change the name and run migration again.

 php artisan migrate:rollback

Properly embedding Youtube video into bootstrap 3.0 page

I use bootstrap 3.x as well and the following code fore responsive youtube video embedding works like charm for me:

.videoWrapperOuter {
  max-width:640px; 
  margin-left:auto;
  margin-right:auto;
}
.videoWrapperInner {
  float: none;
  clear: both;
  width: 100%;
  position: relative;
  padding-bottom: 50%;
  padding-top: 25px;
  height: 0;
}
.videoWrapperInner iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}
<div class="videoWrapperOuter">
  <div class="videoWrapperInner">
    <iframe src="//www.youtube.com/embed/C6-TWRn0k4I" 
      frameborder="0" allowfullscreen></iframe>
  </div>
</div>

I gave a similiar answer on another thread (Shrink a YouTube video to responsive width), but I guess my answers can help here as well.

jQuery, checkboxes and .is(":checked")

Most fastest and easy way:

$('#myCheckbox').change(function(){
    alert(this.checked);
});

$el[0].checked;

$el - is jquery element of selection.

Enjoy!

How do I reference a local image in React?

My answer is basically very similar to that of Rubzen. I use the image as the object value, btw. Two versions work for me:

{
"name": "Silver Card",
"logo": require('./golden-card.png'),

or

const goldenCard = require('./golden-card.png');
{ "name": "Silver Card",
"logo": goldenCard,

Without wrappers - but that is different application, too.

I have checked also "import" solution and in few cases it works (what is not surprising, that is applied in pattern App.js in React), but not in case as mine above.

Using CSS how to change only the 2nd column of a table

Try this:

.countTable table tr td:first-child + td

You could also reiterate in order to style the others columns:

.countTable table tr td:first-child + td + td {...} /* third column */
.countTable table tr td:first-child + td + td + td {...} /* fourth column */
.countTable table tr td:first-child + td + td + td +td {...} /* fifth column */

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

This is usually caused by truncation (the incoming value is too large to fit in the destination column). Unfortunately SSIS will not tell you the name of the offending column. I use a third-party component to get this information: http://naseermuhammed.wordpress.com/tips-tricks/getting-error-column-name-in-ssis/

Display date/time in user's locale format and time offset

You could use the following, which reports the timezone offset from GMT in minutes:

new Date().getTimezoneOffset();

Note : - this function return a negative number.

Alter MySQL table to add comments on columns

try:

 ALTER TABLE `user` CHANGE `id` `id` INT( 11 ) COMMENT 'id of user'  

how to print float value upto 2 decimal place without rounding off

The only easy way to do this is to use snprintf to print to a buffer that's long enough to hold the entire, exact value, then truncate it as a string. Something like:

char buf[2*(DBL_MANT_DIG + DBL_MAX_EXP)];
snprintf(buf, sizeof buf, "%.*f", (int)sizeof buf, x);
char *p = strchr(buf, '.'); // beware locale-specific radix char, though!
p[2+1] = 0;
puts(buf);

Hibernate Annotations - Which is better, field or property access?

I prefer field access, because that way I'm not forced to provide getter/setter for each property.

A quick survey via Google suggests that field access is the majority (e.g., http://java.dzone.com/tips/12-feb-jpa-20-why-accesstype).

I believe field access is the idiom recommended by Spring, but I can't find a reference to back that up.

There's a related SO question that tried to measure performance and came to the conclusion that there's "no difference".

Using multiple .cpp files in c++ program?

You can simply place a forward declaration of your second() function in your main.cpp above main(). If your second.cpp has more than one function and you want all of it in main(), put all the forward declarations of your functions in second.cpp into a header file and #include it in main.cpp.

Like this-

Second.h:

void second();
int third();
double fourth();

main.cpp:

#include <iostream>
#include "second.h"
int main()
{
    //.....
    return 0;
}

second.cpp:

void second()
{
    //...
}

int third()
{ 
    //...
    return foo;
}

double fourth()
{ 
    //...
    return f;
}

Note that: it is not necessary to #include "second.h" in second.cpp. All your compiler need is forward declarations and your linker will do the job of searching the definitions of those declarations in the other files.

What does character set and collation mean exactly?

A character encoding is a way to encode characters so that they fit in memory. That is, if the charset is ISO-8859-15, the euro symbol, €, will be encoded as 0xa4, and in UTF-8, it will be 0xe282ac.

The collation is how to compare characters, in latin9, there are letters as e é è ê f, if sorted by their binary representation, it will go e f é ê è but if the collation is set to, for example, French, you'll have them in the order you thought they would be, which is all of e é è ê are equal, and then f.

How to refresh activity after changing language (Locale) inside application

For Android 4.2 (API 17), you need to use android:configChanges="locale|layoutDirection" in your AndroidManifest.xml. See onConfigurationchanged is not called over jellybean(4.2.1)

Using Rsync include and exclude options to include directory and file by pattern

rsync include exclude pattern examples:

"*"         means everything
"dir1"      transfers empty directory [dir1]
"dir*"      transfers empty directories like: "dir1", "dir2", "dir3", etc...
"file*"     transfers files whose names start with [file]
"dir**"     transfers every path that starts with [dir] like "dir1/file.txt", "dir2/bar/ffaa.html", etc...
"dir***"    same as above
"dir1/*"    does nothing
"dir1/**"   does nothing
"dir1/***"  transfers [dir1] directory and all its contents like "dir1/file.txt", "dir1/fooo.sh", "dir1/fold/baar.py", etc...

And final note is that simply dont rely on asterisks that are used in the beginning for evaluating paths; like "**dir" (its ok to use them for single folders or files but not paths) and note that more than two asterisks dont work for file names.

Is there a library function for Root mean square error (RMSE) in python?

Actually, I did write a bunch of those as utility functions for statsmodels

http://statsmodels.sourceforge.net/devel/tools.html#measure-for-fit-performance-eval-measures

and http://statsmodels.sourceforge.net/devel/generated/statsmodels.tools.eval_measures.rmse.html#statsmodels.tools.eval_measures.rmse

Mostly one or two liners and not much input checking, and mainly intended for easily getting some statistics when comparing arrays. But they have unit tests for the axis arguments, because that's where I sometimes make sloppy mistakes.

Is there a Pattern Matching Utility like GREP in Windows?

I know that it's a bit old topic but, here is another thing you can do. I work on a developer VM with no internet access and quite limited free disk space, so I made use of the java installed on it.

Compile small java program that prints regex matches to the console. Put the jar somewhere on your system, create a batch to execute it and add the folder to your PATH variable:

JGrep.java:

package com.jgrep;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class JGrep {

    public static void main(String[] args) throws FileNotFoundException, IOException {
        int printGroup = -1;
        if (args.length < 2) {
            System.out.println("Invalid arguments. Usage:");
            System.out.println("jgrep [...-MODIFIERS] [PATTERN] [FILENAME]");
            System.out.println("Available modifiers:");
            System.out.println(" -printGroup            - will print the given group only instead of the whole match. Eg: -printGroup=1");
            System.out.println("Current arguments:");
            for (int i = 0; i < args.length; i++) {
                System.out.println("args[" + i + "]=" + args[i]);
            }
            return;
        }
        Pattern pattern = null;
        String filename = args[args.length - 1];
        String patternArg = args[args.length - 2];        
        pattern = Pattern.compile(patternArg);

        int argCount = 2;
        while (args.length - argCount - 1 >= 0) {
            String arg = args[args.length - argCount - 1];
            argCount++;
            if (arg.startsWith("-printGroup=")) {
                printGroup = Integer.parseInt(arg.substring("-printGroup=".length()));
            }
        }
        StringBuilder sb = new StringBuilder();
        try (BufferedReader br = new BufferedReader(new FileReader(filename))) {
            sb = new StringBuilder();
            String line = br.readLine();

            while (line != null) {
                sb.append(line);
                sb.append(System.lineSeparator());
                line = br.readLine();
            }
        }
        Matcher matcher = pattern.matcher(sb.toString());
        int matchesCount = 0;
        while (matcher.find()) {
            if (printGroup > 0) {
                System.out.println(matcher.group(printGroup));
            } else {
                System.out.println(matcher.group());
            }
            matchesCount++;
        }
        System.out.println("----------------------------------------");
        System.out.println("File: " + filename);
        System.out.println("Pattern: " + pattern.pattern());
        System.out.println("PrintGroup: " + printGroup);
        System.out.println("Matches: " + matchesCount);
    }
}

c:\jgrep\jgrep.bat (together with jgrep.jar):

@echo off
java -cp c:\jgrep\jgrep.jar com.jgrep.JGrep %*

and add c:\jgrep in the end of the PATH environment variable.

Now simply call jgrep "expression" file.txt from anywhere.

I needed to print some specific groups from my expression so I added a modifier and call it like jgrep -printGroup=1 "expression" file.txt.

Writing a Python list of lists to a csv file

If for whatever reason you wanted to do it manually (without using a module like csv,pandas,numpy etc.):

with open('myfile.csv','w') as f:
    for sublist in mylist:
        for item in sublist:
            f.write(item + ',')
        f.write('\n')

Of course, rolling your own version can be error-prone and inefficient ... that's usually why there's a module for that. But sometimes writing your own can help you understand how they work, and sometimes it's just easier.

UIButton title text color

swift 5 version:

By using default inbuilt color:

  1. button.setTitleColor(UIColor.green, for: .normal)

OR

You can use your custom color by using RGB method:

  1. button.setTitleColor(UIColor(displayP3Red: 0.0/255.0, green: 180.0/255.0, blue: 2.0/255.0, alpha: 1.0), for: .normal)

Best tool for inspecting PDF files?

My sugession is Foxit PDF Reader which is very helpful to do important text editing work on pdf file.

Importing the private-key/public-certificate pair in the Java KeyStore

With your private key and public certificate, you need to create a PKCS12 keystore first, then convert it into a JKS.

# Create PKCS12 keystore from private key and public certificate.
openssl pkcs12 -export -name myservercert -in selfsigned.crt -inkey server.key -out keystore.p12

# Convert PKCS12 keystore into a JKS keystore
keytool -importkeystore -destkeystore mykeystore.jks -srckeystore keystore.p12 -srcstoretype pkcs12 -alias myservercert

To verify the contents of the JKS, you can use this command:

keytool -list -v -keystore mykeystore.jks

If this was not a self-signed certificate, you would probably want to follow this step with importing the certificate chain leading up to the trusted CA cert.

GET and POST methods with the same Action name in the same Controller

I like to accept a form post for my POST actions, even if I don't need it. For me it just feels like the right thing to do as you're supposedly posting something.

public class HomeController : Controller
{
    public ActionResult Index()
    {
        //Code...
        return View();
    }

    [HttpPost]
    public ActionResult Index(FormCollection form)
    {
        //Code...
        return View();
    }
}

How to display a database table on to the table in the JSP page

The problem here is very simple. If you want to display value in JSP, you have to use <%= %> tag instead of <% %>, here is the solved code:

<tr> <td><%=rs.getInt("ID") %></td> <td><%=rs.getString("NAME") %></td> <td><%=rs.getString("SKILL") %></td> </tr>

Passing data from controller to view in Laravel

Can you give this a try,

return View::make("user/regprofile", compact('students')); OR
return View::make("user/regprofile")->with(array('students'=>$students));

While, you can set multiple variables something like this,

$instructors="";
$instituitions="";

$compactData=array('students', 'instructors', 'instituitions');
$data=array('students'=>$students, 'instructors'=>$instructors, 'instituitions'=>$instituitions);

return View::make("user/regprofile", compact($compactData));
return View::make("user/regprofile")->with($data);

Python Pandas Counting the Occurrences of a Specific value

You can create subset of data with your condition and then use shape or len:

print df
  col1 education
0    a       9th
1    b       9th
2    c       8th

print df.education == '9th'
0     True
1     True
2    False
Name: education, dtype: bool

print df[df.education == '9th']
  col1 education
0    a       9th
1    b       9th

print df[df.education == '9th'].shape[0]
2
print len(df[df['education'] == '9th'])
2

Performance is interesting, the fastest solution is compare numpy array and sum:

graph

Code:

import perfplot, string
np.random.seed(123)


def shape(df):
    return df[df.education == 'a'].shape[0]

def len_df(df):
    return len(df[df['education'] == 'a'])

def query_count(df):
    return df.query('education == "a"').education.count()

def sum_mask(df):
    return (df.education == 'a').sum()

def sum_mask_numpy(df):
    return (df.education.values == 'a').sum()

def make_df(n):
    L = list(string.ascii_letters)
    df = pd.DataFrame(np.random.choice(L, size=n), columns=['education'])
    return df

perfplot.show(
    setup=make_df,
    kernels=[shape, len_df, query_count, sum_mask, sum_mask_numpy],
    n_range=[2**k for k in range(2, 25)],
    logx=True,
    logy=True,
    equality_check=False, 
    xlabel='len(df)')

how to upload file using curl with php

Use:

if (function_exists('curl_file_create')) { // php 5.5+
  $cFile = curl_file_create($file_name_with_full_path);
} else { // 
  $cFile = '@' . realpath($file_name_with_full_path);
}
$post = array('extra_info' => '123456','file_contents'=> $cFile);
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$target_url);
curl_setopt($ch, CURLOPT_POST,1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post);
$result=curl_exec ($ch);
curl_close ($ch);

You can also refer:

http://blog.derakkilgo.com/2009/06/07/send-a-file-via-post-with-curl-and-php/

Important hint for PHP 5.5+:

Now we should use https://wiki.php.net/rfc/curl-file-upload but if you still want to use this deprecated approach then you need to set curl_setopt($ch, CURLOPT_SAFE_UPLOAD, false);

How to delete an item in a list if it exists?

Here's another one-liner approach to throw out there:

next((some_list.pop(i) for i, l in enumerate(some_list) if l == thing), None)

It doesn't create a list copy, doesn't make multiple passes through the list, doesn't require additional exception handling, and returns the matched object or None if there isn't a match. Only issue is that it makes for a long statement.

In general, when looking for a one-liner solution that doesn't throw exceptions, next() is the way to go, since it's one of the few Python functions that supports a default argument.

How to enable loglevel debug on Apache2 server

Edit: note that this answer is 3+ years old. For newer versions of apache, please see the answer by sp00n. Leaving this answer for users of older versions of apache.

For older version apache:

For debugging mod_rewrite issues, you'll want to use RewriteLogLevel and RewriteLog:

RewriteLogLevel 3
RewriteLog "/usr/local/var/apache/logs/rewrite.log"

Simple mediaplayer play mp3 from file path?

I use this class for Audio play. If your audio location is raw folder.

Call method for play:

new AudioPlayer().play(mContext, getResources().getIdentifier(alphabetItemList.get(mPosition)
                        .getDetail().get(0).getAudio(),"raw", getPackageName()));

AudioPlayer.java class:

public class AudioPlayer {

    private MediaPlayer mMediaPlayer;

    public void stop() {
        if (mMediaPlayer != null) {
            mMediaPlayer.release();
            mMediaPlayer = null;
        }
    }
    // mothod for raw folder (R.raw.fileName)
    public void play(Context context, int rid){
        stop();

        mMediaPlayer = MediaPlayer.create(context, rid);
        mMediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
            @Override
            public void onCompletion(MediaPlayer mediaPlayer) {
                stop();
            }
        });

        mMediaPlayer.start();
    }

    // mothod for other folder 
    public void play(Context context, String name) {
        stop();

        //mMediaPlayer = MediaPlayer.create(c, rid);
        mMediaPlayer = MediaPlayer.create(context, Uri.parse("android.resource://"+ context.getPackageName()+"/your_file/"+name+".mp3"));
        mMediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
            @Override
            public void onCompletion(MediaPlayer mediaPlayer) {
                stop();
            }
        });

        mMediaPlayer.start();
    }

}

What is the difference between `let` and `var` in swift?

SIMPLE DIFFERENCE

let = (can not be changed)

var = (any time update)

Turn ON/OFF Camera LED/flash light in Samsung Galaxy Ace 2.2.1 & Galaxy Tab

I will soon released a new version of my app to support to galaxy ace.

You can download here: https://play.google.com/store/apps/details?id=droid.pr.coolflashlightfree

In order to solve your problem you should do this:

this._camera = Camera.open();     
this._camera.startPreview();
this._camera.autoFocus(new AutoFocusCallback() {
public void onAutoFocus(boolean success, Camera camera) {
}
});

Parameters params = this._camera.getParameters();
params.setFlashMode(Parameters.FLASH_MODE_ON);
this._camera.setParameters(params);

params = this._camera.getParameters();
params.setFlashMode(Parameters.FLASH_MODE_OFF);
this._camera.setParameters(params);

don't worry about FLASH_MODE_OFF because this will keep the light on, strange but it's true

to turn off the led just release the camera

what's data-reactid attribute in html?

It's a custom html attribute but probably in this case is used by the Facebook React JS Library.

Take a look: http://facebook.github.io/react/

Strings as Primary Keys in SQL Database

From performance standpoint - Yes string(PK) will slow down the performance when compared to performance achieved using an integer(PK), where PK ---> Primary Key.

From requirement standpoint - Although this is not a part of your question still I would like to mention. When we are handling huge data across different tables we generally look for the probable set of keys that can be set for a particular table. This is primarily because there are many tables and mostly each or some table would be related to the other through some relation ( a concept of Foreign Key ). Therefore we really cannot always choose an integer as a Primary Key, rather we go for a combination of 3, 4 or 5 attributes as the primary key for that tables. And those keys can be used as a foreign key when we would relate the records with some other table. This makes it useful to relate the records across different tables when required.

Therefore for Optimal Usage - We always make a combination of 1 or 2 integers with 1 or 2 string attributes, but again only if it is required.

PHP unable to load php_curl.dll extension

In php.ini you must put the extension_dir static path. extension_dir = "C:\laragon\bin\php\php-7.3.11-Win32-VC15-x64\ext" by example. Don't forget to remove the semicolon before this variable.

Pass user defined environment variable to tomcat

Environment Entries specified by <Environment> markup are JNDI, accessible using InitialContext.lookup under java:/comp/env. You can specify environment properties to the JNDI by using the environment parameter to the InitialContext constructor and application resource files.

System.getEnv() is about system environment variables of the tomcat process itself.

To set an environment variable using bash command : export TOMCAT_OPTS=-Dmy.bar=foo and start the Tomcat : ./startup.sh To retrieve the value of System property bar use System.getProperty(). System.getEnv() can be used to retrieve the environment variable i.e. TOMCAT_OPTS.

Dynamic type languages versus static type languages

It is all about the right tool for the job. Neither is better 100% of the time. Both systems were created by man and have flaws. Sorry, but we suck and making perfect stuff.

I like dynamic typing because it gets out of my way, but yes runtime errors can creep up that I didn't plan for. Where as static typing may fix the aforementioned errors, but drive a novice(in typed languages) programmer crazy trying to cast between a constant char and a string.

Convert date to day name e.g. Mon, Tue, Wed

Seems like you could use date() and the lowercase "L" format character in the following way:

$weekday_name = date("l", $timestamp);

Works well for me, here is the doc: http://php.net/manual/en/function.date.php

C program to check little vs. big endian

The following will do.

unsigned int x = 1;
printf ("%d", (int) (((char *)&x)[0]));

And setting &x to char * will enable you to access the individual bytes of the integer, and the ordering of bytes will depend on the endianness of the system.

Remove menubar from Electron app

Use this:

mainWindow = new BrowserWindow({width: 640, height: 360})
mainWindow.setMenuBarVisibility(false)

Reference: https://github.com/electron/electron/issues/1415

I tried mainWindow.setMenu(null), but it didn't work.

To show error message without alert box in Java Script

I m agree with @ReNjITh.R answer but If you want to display error message just beside textbox. Just like below

enter image description here

<html>
<head>
<script type="text/javascript">
    function validate() 
    {
        if(myform.fname.value.length==0)
        {
           document.getElementById('errfn').innerHTML="this is invalid name";
        }
    }
</script>
</head>
<body>
    <form name="myform">
         First_Name
         <input type=text id=fname name=fname onblur="validate()" /><span id="errfn"></span>
        <br> <br>
         Last_Name
         <input type=text id=lname name=lname onblur="validate()"/><br>
         <input type=button value=check /> 
    </form>
</body>

Contains method for a slice

The sort package provides the building blocks if your slice is sorted or you are willing to sort it.

input := []string{"bird", "apple", "ocean", "fork", "anchor"}
sort.Strings(input)

fmt.Println(contains(input, "apple")) // true
fmt.Println(contains(input, "grow"))  // false

...

func contains(s []string, searchterm string) bool {
    i := sort.SearchStrings(s, searchterm)
    return i < len(s) && s[i] == searchterm
}

SearchString promises to return the index to insert x if x is not present (it could be len(a)), so a check of that reveals whether the string is contained the sorted slice.

How to pass command line arguments to a rake task

Actually @Nick Desjardins answered perfect. But just for education: you can use dirty approach: using ENV argument

task :my_task do
  myvar = ENV['myvar']
  puts "myvar: #{myvar}"
end 

rake my_task myvar=10
#=> myvar: 10

Can Mockito capture arguments of a method called multiple times?

With Java 8's lambdas, a convenient way is to use

org.mockito.invocation.InvocationOnMock

when(client.deleteByQuery(anyString(), anyString())).then(invocationOnMock -> {
    assertEquals("myCollection", invocationOnMock.getArgument(0));
    assertThat(invocationOnMock.getArgument(1), Matchers.startsWith("id:"));
}

String split on new line, tab and some number of spaces

Just use .strip(), it removes all whitespace for you, including tabs and newlines, while splitting. The splitting itself can then be done with data_string.splitlines():

[s.strip() for s in data_string.splitlines()]

Output:

>>> [s.strip() for s in data_string.splitlines()]
['Name: John Smith', 'Home: Anytown USA', 'Phone: 555-555-555', 'Other Home: Somewhere Else', 'Notes: Other data', 'Name: Jane Smith', 'Misc: Data with spaces']

You can even inline the splitting on : as well now:

>>> [s.strip().split(': ') for s in data_string.splitlines()]
[['Name', 'John Smith'], ['Home', 'Anytown USA'], ['Phone', '555-555-555'], ['Other Home', 'Somewhere Else'], ['Notes', 'Other data'], ['Name', 'Jane Smith'], ['Misc', 'Data with spaces']]

Where to download Microsoft Visual c++ 2003 redistributable

After a bit of googling, it seems that there never was a separate redistributable for Visual C++ 2003 (7.1). At least that is what a post on the microsoft forum says.

You may however be able to extract the runtime DLLs from the VC 7.1 DST timezone update.

Where are static variables stored in C and C++?

This is how (easy to understand):

stack, heap and static data

Can I add color to bootstrap icons only using CSS?

Quick and dirty work around which did it for me, not actually coloring the icon, but surrounding it with a label or badge in the color you want;

<span class="label-important label"><i class="icon-remove icon-white"></i></span>
<span class="label-success label"><i class="icon-ok icon-white"></i></span>

Define variable to use with IN operator (T-SQL)

There are two ways to tackle dynamic csv lists for TSQL queries:

1) Using an inner select

SELECT * FROM myTable WHERE myColumn in (SELECT id FROM myIdTable WHERE id > 10)

2) Using dynamically concatenated TSQL

DECLARE @sql varchar(max)  
declare @list varchar(256)  
select @list = '1,2,3'  
SELECT @sql = 'SELECT * FROM myTable WHERE myColumn in (' + @list + ')'

exec sp_executeSQL @sql

3) A possible third option is table variables. If you have SQl Server 2005 you can use a table variable. If your on Sql Server 2008 you can even pass whole table variables in as a parameter to stored procedures and use it in a join or as a subselect in the IN clause.

DECLARE @list TABLE (Id INT)

INSERT INTO @list(Id)
SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4


SELECT
    * 
FROM 
    myTable
    JOIN @list l ON myTable.myColumn = l.Id

SELECT
    * 
FROM 
    myTable
WHERE
    myColumn IN (SELECT Id FROM @list)

Get IPv4 addresses from Dns.GetHostEntry()

To find all local IPv4 addresses:

IPAddress[] ipv4Addresses = Array.FindAll(
    Dns.GetHostEntry(string.Empty).AddressList,
    a => a.AddressFamily == AddressFamily.InterNetwork);

or use Array.Find or Array.FindLast if you just want one.

How to use a RELATIVE path with AuthUserFile in htaccess?

Let's take an example.

Your application is located in /var/www/myApp on some Linux server

.htaccess : /var/www/myApp/.htaccess

htpasswdApp : /var/www/myApp/htpasswdApp. (You're free to use any name for .htpasswd file)

To use relative path in .htaccess:

AuthType Digest
AuthName myApp
AuthUserFile "htpasswdApp"
Require valid-user

But it will search for file in server_root directory. Not in document_root.

In out case, when application is located at /var/www/myApp :

document_root is /var/www/myApp

server_root is /etc/apache2 //(just in our example, because of we using the linux server)

You can redefine it in your apache configuration file ( /etc/apache2/apache2.conf), but I guess it's a bad idea.

So to use relative file path in your /var/www/myApp/.htaccess you should define the password's file in your server_root.

I prefer to do it by follow command:

sudo ln -s /var/www/myApp/htpasswdApp /etc/apache2/htpasswdApp

You're free to copy my command, use a hard link instead of symbol,or copy a file to your server_root.

UITableView with fixed section headers

The headers only remain fixed when the UITableViewStyle property of the table is set to UITableViewStylePlain. If you have it set to UITableViewStyleGrouped, the headers will scroll up with the cells.

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.

onchange event for input type="number"

<input type="number" id="n" value="0" step=".5" />
<input type="hidden" id="v" value = "0"/>

<script>
$("#n").bind('keyup mouseup', function () {
    var current = $("#n").val();
    var prevData = $("#v").val(); 
    if(current > prevData || current < prevData){
       $("#v").val(current);
       var newv = $("#v").val(); 
       alert(newv);
    } 
});  
</script>

http://jsfiddle.net/patrickrobles53/s10wLjL3/

I've used a hidden input type to be the container of the previous value that will be needed for the comparison on the next change.

What is the shortcut in IntelliJ IDEA to find method / functions?

CTRL + F12 brings up the File Structure navigation menu, which lets you search for members of the currently open file.

How to retrieve data from a SQL Server database in C#?

To retrieve data from database:

private SqlConnection Conn;
 private void CreateConnection()
 {
    string ConnStr =
    ConfigurationManager.ConnectionStrings["ConnStr"].ConnectionString;
    Conn = new SqlConnection(ConnStr);
 }
 public DataTable getData()
 {
 CreateConnection();
    string SqlString = "SELECT * FROM TableName WHERE SomeID = @SomeID;";
    SqlDataAdapter sda = new SqlDataAdapter(SqlString, Conn);
    DataTable dt = new DataTable();
    try
    {
        Conn.Open();
        sda.Fill(dt);
    }
    catch (SqlException se)
    {
        DBErLog.DbServLog(se, se.ToString());
    }
    finally
    {
        Conn.Close();
    }
    return dt;
}

Better way to cast object to int

You can first cast object to string and then cast the string to int; for example:

string str_myobject = myobject.ToString();
int int_myobject = int.Parse(str_myobject);

this worked for me.

AttributeError: 'datetime' module has no attribute 'strptime'

If I had to guess, you did this:

import datetime

at the top of your code. This means that you have to do this:

datetime.datetime.strptime(date, "%Y-%m-%d")

to access the strptime method. Or, you could change the import statement to this:

from datetime import datetime

and access it as you are.

The people who made the datetime module also named their class datetime:

#module  class    method
datetime.datetime.strptime(date, "%Y-%m-%d")

How does the JPA @SequenceGenerator annotation work

I have MySQL schema with autogen values. I use strategy=GenerationType.IDENTITY tag and seems to work fine in MySQL I guess it should work most db engines as well.

CREATE TABLE user (
    id bigint NOT NULL auto_increment,
    name varchar(64) NOT NULL default '',
    PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

User.java:

// mark this JavaBean to be JPA scoped class
@Entity
@Table(name="user")
public class User {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private long id;    // primary key (autogen surrogate)

    @Column(name="name")
    private String name;

    public long getId() { return id; }
    public void setId(long id) { this.id = id; }

    public String getName() { return name; }
    public void setName(String name) { this.name=name; }
}

How to split data into 3 sets (train, validation and test)?

Note:

Function was written to handle seeding of randomized set creation. You should not rely on set splitting that doesn't randomize the sets.

import numpy as np
import pandas as pd

def train_validate_test_split(df, train_percent=.6, validate_percent=.2, seed=None):
    np.random.seed(seed)
    perm = np.random.permutation(df.index)
    m = len(df.index)
    train_end = int(train_percent * m)
    validate_end = int(validate_percent * m) + train_end
    train = df.iloc[perm[:train_end]]
    validate = df.iloc[perm[train_end:validate_end]]
    test = df.iloc[perm[validate_end:]]
    return train, validate, test

Demonstration

np.random.seed([3,1415])
df = pd.DataFrame(np.random.rand(10, 5), columns=list('ABCDE'))
df

enter image description here

train, validate, test = train_validate_test_split(df)

train

enter image description here

validate

enter image description here

test

enter image description here

How to format numbers?

You may want to consider using toLocaleString()

Working Example:

_x000D_
_x000D_
const number = 1234567890.123;

console.log(number.toLocaleString('en-US')); // US format

console.log(number.toLocaleString('en-IN')); // Indian format
_x000D_
_x000D_
_x000D_

Tested in Chrome v60 and v88

Source: Number.prototype.toLocaleString() | MDN

Why is it said that "HTTP is a stateless protocol"?

Modern HTTP is stateful. Old timey HTTP was stateless.

Before Netscape invented cookies and HTTPS in 1994 http could be considered stateless. As time progressed more and more stateful aspects were added for a myriad of reasons, including performance and security.

While HTTP 1 originally sought out to be stateless many HTTP/2 components are the very definition of stateful. HTTP/2 abandoned stateless goals.

No reasonable person can read the HTTP/2 RFC and think it is stateless. The errant "HTTP is stateless" old time dogma is false and far from the current reality of stateful HTTP.

Here's a limited, and not exhaustive list, of stateful HTTP/1 and HTTP/2 components:

  • Cookies, named "HTTP State Management Mechanism" by the RFC.
  • HTTPS, which stores keys thus state.
  • HTTP authentication requires state.
  • Web Storage.
  • HTTP caching is stateful.
  • The very purpose of the stream identifier is state. It's even in the name of the RFC section, "Stream States".
  • Header blocks, which establish stream identifiers, are stateful.
  • Frames which reference stream identifiers are stateful.
  • Header Compression, which the HTTP RFC explicitly says is stateful, is stateful.
  • Opportunistic encryption is stateful.

Section 5.1 of the HTTP/2 RFC is a great example of stateful mechanisms defined by the HTTP/2 standard.

Is it safe for web applications to consider HTTP/2 as a stateless protocol?

HTTP/2 is a stateful protocol, but that doesn't mean your HTTP/2 application can't be stateless. You can choose to not use certain stateful features for stateless HTTP/2 applications by using only a subset of HTTP/2 features.

Cookies and some other stateful mechanisms, or less obvious stateful mechanisms, are later HTTP additions. HTTP 1 is said to be stateless although in practice we use standardized stateful mechanisms, like cookies, TLS, and caching. Unlike HTTP/1, HTTP/2 defines stateful components in its standard from the very beginning. A particular HTTP/2 application can use a subset of HTTP/2 features to maintain statelessness, but the protocol itself anticipate state to be the norm, not the exception.

Existing applications, even HTTP 1 applications, needing state will break if trying to use them statelessly. It can be impossible to log into some HTTP/1.1 websites if cookies are disabled, thus breaking the application. It may not be safe to assume that a particular HTTP 1 application does not use state. This is no different for HTTP/2.

Say it with me one last time:

HTTP/2 is a stateful protocol.

How to align checkboxes and their labels consistently cross-browsers

input {
    margin: 0;
}

actually does the trick

Display text from .txt file in batch file

Here is a good date and time code:

@echo off
if %date:~4,2%==01 set month=January
if %date:~4,2%==02 set month=February
if %date:~4,2%==03 set month=March
if %date:~4,2%==04 set month=April
if %date:~4,2%==05 set month=May
if %date:~4,2%==06 set month=June
if %date:~4,2%==07 set month=July
if %date:~4,2%==08 set month=August
if %date:~4,2%==09 set month=September
if %date:~4,2%==10 set month=October
if %date:~4,2%==11 set month=November
if %date:~4,2%==12 set month=December

if %date:~0,3%==Mon set day=Monday
if %date:~0,3%==Tue set day=Tuesday
if %date:~0,3%==Wed set day=Wednesday
if %date:~0,3%==Thu set day=Thursday
if %date:~0,3%==Fri set day=Friday
if %date:~0,3%==Sat set day=Saturday
if %date:~0,3%==Sun set day=Sunday
echo.
echo The Date is %day%, %month% %date:~7,2%, %date:~10,4% the current time is: %time:~0,5%
pause

Outputs: The Date is Sunday, September 27, 2009 the current time is: 3:07

Merging two CSV files using Python

When I'm working with csv files, I often use the pandas library. It makes things like this very easy. For example:

import pandas as pd

a = pd.read_csv("filea.csv")
b = pd.read_csv("fileb.csv")
b = b.dropna(axis=1)
merged = a.merge(b, on='title')
merged.to_csv("output.csv", index=False)

Some explanation follows. First, we read in the csv files:

>>> a = pd.read_csv("filea.csv")
>>> b = pd.read_csv("fileb.csv")
>>> a
   title  stage    jan    feb
0   darn  3.001  0.421  0.532
1     ok  2.829  1.036  0.751
2  three  1.115  1.146  2.921
>>> b
   title    mar    apr    may       jun  Unnamed: 5
0   darn  0.631  1.321  0.951    1.7510         NaN
1     ok  1.001  0.247  2.456    0.3216         NaN
2  three  0.285  1.283  0.924  956.0000         NaN

and we see there's an extra column of data (note that the first line of fileb.csv -- title,mar,apr,may,jun, -- has an extra comma at the end). We can get rid of that easily enough:

>>> b = b.dropna(axis=1)
>>> b
   title    mar    apr    may       jun
0   darn  0.631  1.321  0.951    1.7510
1     ok  1.001  0.247  2.456    0.3216
2  three  0.285  1.283  0.924  956.0000

Now we can merge a and b on the title column:

>>> merged = a.merge(b, on='title')
>>> merged
   title  stage    jan    feb    mar    apr    may       jun
0   darn  3.001  0.421  0.532  0.631  1.321  0.951    1.7510
1     ok  2.829  1.036  0.751  1.001  0.247  2.456    0.3216
2  three  1.115  1.146  2.921  0.285  1.283  0.924  956.0000

and finally write this out:

>>> merged.to_csv("output.csv", index=False)

producing:

title,stage,jan,feb,mar,apr,may,jun
darn,3.001,0.421,0.532,0.631,1.321,0.951,1.751
ok,2.829,1.036,0.751,1.001,0.247,2.456,0.3216
three,1.115,1.146,2.921,0.285,1.283,0.924,956.0

How to get Wikipedia content using Wikipedia's API?

You can use the extract_html field of the summary REST endpoint for this: e.g. https://en.wikipedia.org/api/rest_v1/page/summary/Cat.

Note: This aims to simply the content a bit by removing most of the pronunciations, mainly in parentheses in some cases.

How to use the PRINT statement to track execution as stored procedure is running?

SQL Server returns messages after a batch of statements has been executed. Normally, you'd use SQL GO to indicate the end of a batch and to retrieve the results:

PRINT '1'
GO

WAITFOR DELAY '00:00:05'

PRINT '2'
GO

WAITFOR DELAY '00:00:05'

PRINT '3'
GO

In this case, however, the print statement you want returned immediately is in the middle of a loop, so the print statements cannot be in their own batch. The only command I know of that will return in the middle of a batch is RAISERROR (...) WITH NOWAIT, which gbn has provided as an answer as I type this.

What's the best way to break from nested loops in JavaScript?

Wrap that up in a function and then just return.

Simple way to convert datarow array to datatable

DataTable dt = new DataTable();
foreach (DataRow dr in drResults)
{ 
    dt.ImportRow(dr);
}   

Why does the 'int' object is not callable error occur when using the sum() function?

In the interpreter its easy to restart it and fix such problems. If you don't want to restart the interpreter, there is another way to fix it:

Python 2.6.6 (r266:84292, Dec 27 2010, 00:02:40)
[GCC 4.4.5] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> l = [1,2,3]
>>> sum(l)
6
>>> sum = 0 # oops! shadowed a builtin!
>>> sum(l)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'int' object is not callable
>>> import sys
>>> sum = sys.modules['__builtin__'].sum # -- fixing sum
>>> sum(l)
6

This also comes in handy if you happened to assign a value to any other builtin, like dict or list

How do I export (and then import) a Subversion repository?

You can also use the svnadmin hotcopy command:

svnadmin hotcopy OLD_REPOS_PATH NEW_REPOS_PATH

It takes a full backup from repository, including all hooks, configuration files, etc.

More at SVN Book

How to echo print statements while executing a sql script

This will give you are simple print within a sql script:

select 'This is a comment' AS '';

Alternatively, this will add some dynamic data to your status update if used directly after an update, delete, or insert command:

select concat ("Updated ", row_count(), " rows") as ''; 

Error TF30063: You are not authorized to access ... \DefaultCollection

I have upgraded TFS 2015 to TFS 2017, and then the TF30063 error occured on one of my client machines. None of the solutions here worked...

For me the only solution that worked was running the following command from the Developer Command Prompt:

tf workspaces /collection:https://tfs.xxxxx.com/tfs/DefaultCollection

Of course, you need to adjust the url to the valid one.

Source: https://www.visualstudio.com/en-us/docs/setup-admin/tfs/admin/backup/refresh-data-caches

CSS :: child set to change color on parent hover, but changes also when hovered itself

If you don't care about supporting old browsers, you can use :not() to exclude that element:

.parent:hover span:not(:hover) {
    border: 10px solid red;
}

Demo: http://jsfiddle.net/vz9A9/1/

If you do want to support them, the I guess you'll have to either use JavaScript or override the CSS properties again:

.parent span:hover {
    border: 10px solid green;
}

How to use icons and symbols from "Font Awesome" on Native Android Application

There's another nice solution which you can use in your layout xml files directly and does not require to use setTypeface.

It is Joan Zapata's Iconify. You can read here what's new in Iconify v2. It includes 9 different font libraries which you can simply use by adding dependencies to your build.gradle file.

In the layout xml files it's possible to choose between these widgets:

com.joanzapata.iconify.widget.IconTextview
com.joanzapata.iconify.widget.IconButton
com.joanzapata.iconify.widget.IconToggleButton

Numpy where function multiple conditions

Try:

import numpy as np
dist = np.array([1,2,3,4,5])
r = 2
dr = 3
np.where(np.logical_and(dist> r, dist<=r+dr))

Output: (array([2, 3]),)

You can see Logic functions for more details.

How to convert int[] to Integer[] in Java?

Update: Though the below compiles, it throws a ArrayStoreException at runtime. Too bad. I'll let it stay for future reference.


Converting an int[], to an Integer[]:

int[] old;
...
Integer[] arr = new Integer[old.length];
System.arraycopy(old, 0, arr, 0, old.length);

I must admit I was a bit surprised that this compiles, given System.arraycopy being lowlevel and everything, but it does. At least in java7.

You can convert the other way just as easily.

How to "inverse match" with regex?

(?!Andrea).{6}

Assuming your regexp engine supports negative lookaheads..

Edit: ..or maybe you'd prefer to use [A-Za-z]{6} in place of .{6}

Edit (again): Note that lookaheads and lookbehinds are generally not the right way to "inverse" a regular expression match. Regexps aren't really set up for doing negative matching, they leave that to whatever language you are using them with.

How to modify JsonNode in Java?

You need to get ObjectNode type object in order to set values. Take a look at this

Unloading classes in java?

Classes have an implicit strong reference to their ClassLoader instance, and vice versa. They are garbage collected as with Java objects. Without hitting the tools interface or similar, you can't remove individual classes.

As ever you can get memory leaks. Any strong reference to one of your classes or class loader will leak the whole thing. This occurs with the Sun implementations of ThreadLocal, java.sql.DriverManager and java.beans, for instance.

Disable back button in android

If you want to disable your app while logging out, you can pop up a non-cancellable dialog.

If hasClass then addClass to parent

Alternatively you could use:

if ($('#navigation a').is(".active")) {
    $(this).parent().addClass("active");
}

How to get all elements inside "div" that starts with a known text

i have tested a sample and i would like to share this sample and i am sure it's quite help full. I have done all thing in body, first creating an structure there on click of button you will call a function selectallelement(); on mouse click which will pass the id of that div about which you want to know the childrens. I have given alerts here on different level so u can test where r u now in the coding .

    <body>
    <h1>javascript to count the number of children of given child</h1>

    <div id="count">
    <span>a</span>
    <span>s</span>
    <span>d</span>
    <span>ff</span>
    <div>fsds</div>
    <p>fffff</p>
    </div>
   <button type="button" onclick="selectallelement('count')">click</button>
   <p>total element no.</p>
    <p id="sho">here</p>
  <script>

  function selectallelement(divid)
  {
 alert(divid);
 var ele = document.getElementById(divid).children;
 var match = new Array();
  var i = fillArray(ele,match);
  alert(i);
   document.getElementById('sho').innerHTML = i;
  }
 function fillArray(e1,a1)
  {
 alert("we are here");
   for(var i =0;i<e1.length;i++)
{
  if(e1[i].id.indexOf('count') == 0)
    a1.push(e1[i]);
}
return i;
   }
   </script>

 </body>

  USE THIS I AM SURE U WILL GET YOUR ANSWER ...THANKS 

ASP.Net MVC How to pass data from view to controller

You can do it with ViewModels like how you passed data from your controller to view.

Assume you have a viewmodel like this

public class ReportViewModel
{
   public string Name { set;get;}
}

and in your GET Action,

public ActionResult Report()
{
  return View(new ReportViewModel());
}

and your view must be strongly typed to ReportViewModel

@model ReportViewModel
@using(Html.BeginForm())
{
  Report NAme : @Html.TextBoxFor(s=>s.Name)
  <input type="submit" value="Generate report" />
}

and in your HttpPost action method in your controller

[HttpPost]
public ActionResult Report(ReportViewModel model)
{
  //check for model.Name property value now
  //to do : Return something
}

OR Simply, you can do this without the POCO classes (Viewmodels)

@using(Html.BeginForm())
{
   <input type="text" name="reportName" />
   <input type="submit" />
}

and in your HttpPost action, use a parameter with same name as the textbox name.

[HttpPost]
public ActionResult Report(string reportName)
{
  //check for reportName parameter value now
  //to do : Return something
}

EDIT : As per the comment

If you want to post to another controller, you may use this overload of the BeginForm method.

@using(Html.BeginForm("Report","SomeOtherControllerName"))
{
   <input type="text" name="reportName" />
   <input type="submit" />
}

Passing data from action method to view ?

You can use the same view model, simply set the property values in your GET action method

public ActionResult Report()
{
  var vm = new ReportViewModel();
  vm.Name="SuperManReport";
  return View(vm);
}

and in your view

@model ReportViewModel
<h2>@Model.Name</h2>
<p>Can have input field with value set in action method</p>
@using(Html.BeginForm())
{
  @Html.TextBoxFor(s=>s.Name)
  <input type="submit" />
}

Remove all special characters with RegExp

Note that if you still want to exclude a set, including things like slashes and special characters you can do the following:

var outString = sourceString.replace(/[`~!@#$%^&*()_|+\-=?;:'",.<>\{\}\[\]\\\/]/gi, '');

take special note that in order to also include the "minus" character, you need to escape it with a backslash like the latter group. if you don't it will also select 0-9 which is probably undesired.

Execute Insert command and return inserted Id in Sql

The following solution will work with sql server 2005 and above. You can use output to get the required field. inplace of id you can write your key that you want to return. do it like this

FOR SQL SERVER 2005 and above

    using(SqlCommand cmd=new SqlCommand("INSERT INTO Mem_Basic(Mem_Na,Mem_Occ) output INSERTED.ID VALUES(@na,@occ)",con))
    {
        cmd.Parameters.AddWithValue("@na", Mem_NA);
        cmd.Parameters.AddWithValue("@occ", Mem_Occ);
        con.Open();

        int modified =(int)cmd.ExecuteScalar();

        if (con.State == System.Data.ConnectionState.Open) 
            con.Close();

        return modified;
    }
}

FOR previous versions

    using(SqlCommand cmd=new SqlCommand("INSERT INTO Mem_Basic(Mem_Na,Mem_Occ)  VALUES(@na,@occ);SELECT SCOPE_IDENTITY();",con))
    {
        cmd.Parameters.AddWithValue("@na", Mem_NA);
        cmd.Parameters.AddWithValue("@occ", Mem_Occ);
        con.Open();

        int modified = Convert.ToInt32(cmd.ExecuteScalar());

        if (con.State == System.Data.ConnectionState.Open) con.Close();
            return modified;
    }
}

Javascript replace all "%20" with a space

Use the global flag in regexp:

var replaced = str.replace(/%20/g, " ");
                                ^

Why would anybody use C over C++?

I take the other view: why use C++ instead of C?

The book The C Programming Language (aka: K&R) tells you clearly how to do everything the language can do in under 300 pages. It's a masterpiece of minimalism. No C++ book even comes close.

The obvious counterargument is that the same could be said of most, if not all, modern languages -- they also can't tell you how to do everything in only a few hundred pages. True. So why use C++ instead? Feature richness? Power? If you need something more feature rich or powerful then go with C#, Objective C, Java, or something else like that. Why burden yourself with the complexities of C++? If you need the degree of control C++ grants then I argue to use C. C can do anything and can do it well.

How to force Hibernate to return dates as java.util.Date instead of Timestamp?

A simple alternative to using a custom UserType is to construct a new java.util.Date in the setter for the date property in your persisted bean, eg:

import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.Column;

@Entity
public class Purchase {

    private Date date;

    @Column
    public Date getDate() {
        return this.date;
    }

    public void setDate(Date date) {
        // force java.sql.Timestamp to be set as a java.util.Date
        this.date = new Date(date.getTime());
    }

}

Finding common rows (intersection) in two Pandas dataframes

My understanding is that this question is better answered over in this post.

But briefly, the answer to the OP with this method is simply:

s1 = pd.merge(df1, df2, how='inner', on=['user_id'])

Which gives s1 with 5 columns: user_id and the other two columns from each of df1 and df2.

How do I conditionally add attributes to React components?

For example using property styles for custom container

const DriverSelector = props => {
  const Container = props.container;
  const otherProps = {
    ...( props.containerStyles && { style: props.containerStyles } )
  };

  return (
    <Container {...otherProps} >

Adding Image to xCode by dragging it from File

For xCode 10, first you need to add the image in your assetsCatalogue and then type this:

let imageView = UIImageView(image: #imageLiteral(resourceName: "type the name of your image here..."))

For beginners, let imageView is the name of the UIImageView object we are about to create.

An example for embedding an image into a viewControler file would look like this:

import UIKit

class TutorialViewCotroller: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        let imageView = UIImageView(image: #imageLiteral(resourceName: "intoImage"))
        view.addSubview(imageView)
    }
}

Please notice that I did not use any extension for the image file name, as in my case it is a group of images.

docker: "build" requires 1 argument. See 'docker build --help'

You need to add a dot, which means to use the Dockerfile in the local directory.

For example:

docker build -t mytag .

It means you use the Dockerfile in the local directory, and if you use docker 1.5 you can specify a Dockerfile elsewhere. Extract from the help output from docker build:

-f, --file="" Name of the Dockerfile(Default is 'Dockerfile' at context root)

Border around specific rows in a table?

Based on your requirement that you want to put a border around an arbitrary block of MxN cells there really is no easier way of doing it without using Javascript. If your cells are fixed with you can use floats but this is problematic for other reasons. what you're doing may be tedious but it's fine.

Ok, if you're interested in a Javascript solution, using jQuery (my preferred approach), you end up with this fairly scary piece of code:

<html>
<head>

<style type="text/css">
td.top { border-top: thin solid black; }
td.bottom { border-bottom: thin solid black; }
td.left { border-left: thin solid black; }
td.right { border-right: thin solid black; }
</style>
<script type="text/javascript" src="jquery-1.3.1.js"></script>
<script type="text/javascript">
$(function() {
  box(2, 1, 2, 2);
});

function box(row, col, height, width) {
  if (typeof height == 'undefined') {
    height = 1;
  }
  if (typeof width == 'undefined') {
    width = 1;
  }
  $("table").each(function() {
    $("tr:nth-child(" + row + ")", this).children().slice(col - 1, col + width - 1).addClass("top");
    $("tr:nth-child(" + (row + height - 1) + ")", this).children().slice(col - 1, col + width - 1).addClass("bottom");
    $("tr", this).slice(row - 1, row + height - 1).each(function() {
      $(":nth-child(" + col + ")", this).addClass("left");
      $(":nth-child(" + (col + width - 1) + ")", this).addClass("right");
    });
  });
}
</script>
</head>
<body>

<table cellspacing="0">
  <tr>
    <td>no border</td>
    <td>no border here either</td>
  </tr>
  <tr>
    <td>one</td>
    <td>two</td>
  </tr>
  <tr>
    <td>three</td>
    <td>four</td>
  </tr>
  <tr>
    <td colspan="2">once again no borders</td>
  </tr>
</tfoot>
</table>
</html>

I'll happily take suggestions on easier ways to do this...

PHP Array to JSON Array using json_encode();

I had a problem with accented characters when converting a PHP array to JSON. I put UTF-8 stuff all over the place but nothing solved my problem until I added this piece of code in my PHP while loop where I was pushing the array:

$es_words[] = array(utf8_encode("$word"),"$alpha","$audio");

It was only the '$word' variable that was giving a problem. Afterwards it did a jason_encode no problem.

Hope that helps

Python "\n" tag extra line

The print function in python adds itself \n

You could use

import sys
sys.stdout.write(a)

instead

SQL query, if value is null then return 1

a) If you want 0 when value is null

SELECT isnull(PartNum,0) AS PartNumber, PartID
FROM Part

b) If you want 0 when value is null and otherwise 1

SELECT 
  (CASE
    WHEN PartNum IS NULL THEN 0
    ELSE 1
  END) AS PartNumber,
  PartID
FROM Part

Attach Authorization header for all axios requests

Try to make new instance like i did below

var common_axios = axios.create({
    baseURL: 'https://sample.com'
});

// Set default headers to common_axios ( as Instance )
common_axios.defaults.headers.common['Authorization'] = AUTH_TOKEN;
// Check your Header
console.log(common_axios.defaults.headers);

How to Use it

common_axios.get(url).......
common_axios.post(url).......

How to create a Rectangle object in Java using g.fillRect method

Note:drawRect and fillRect are different.

Draws the outline of the specified rectangle:

public void drawRect(int x,
        int y,
        int width,
        int height)

Fills the specified rectangle. The rectangle is filled using the graphics context's current color:

public abstract void fillRect(int x,
        int y,
        int width,
        int height)

Can not find the tag library descriptor of springframework

I finally configured RAD to build my Maven-based project, but was getting the following exception when I navigate to a page that uses the Spring taglib:

JSPG0047E: Unable to locate tag library for uri http://www.springframework.org/tags at com.ibm.ws.jsp.translator.visitor.tagfiledep.TagFileDependencyVisitor.visitCustomTagStart(TagFileDependencyVisitor.java:76) ...

The way I had configured my EAR, all the jars were in the EAR, not in the WAR’s WEB-INF/lib. According to the JSP 2.0 spec, I believe tag libs are searched for in all subdirectories of WEB-INF, hence the issue. My solution was to copy the tld files and place under WEB-INF/lib or WEB-INF.. Then it worked.

Swift - Split string over multiple lines

Adding to @Connor answer, there needs to be \n also. Here is revised code:

var text:String = "This is some text \n" +
                  "over multiple lines"

Change bar plot colour in geom_bar with ggplot2 in r

If you want all the bars to get the same color (fill), you can easily add it inside geom_bar.

ggplot(data=df, aes(x=c1+c2/2, y=c3)) + 
geom_bar(stat="identity", width=c2, fill = "#FF6666")

enter image description here

Add fill = the_name_of_your_var inside aes to change the colors depending of the variable :

c4 = c("A", "B", "C")
df = cbind(df, c4)
ggplot(data=df, aes(x=c1+c2/2, y=c3, fill = c4)) + 
geom_bar(stat="identity", width=c2)

enter image description here

Use scale_fill_manual() if you want to manually the change of colors.

ggplot(data=df, aes(x=c1+c2/2, y=c3, fill = c4)) + 
geom_bar(stat="identity", width=c2) + 
scale_fill_manual("legend", values = c("A" = "black", "B" = "orange", "C" = "blue"))

enter image description here

Conversion of a datetime2 data type to a datetime data type results out-of-range value

Problem with inherited datetime attribute

This error message is often showed when a non-nullable date field has value null at insert/update time. One cause can be inheritance.

If your date is inherit from a base-class and you don't make a mapping EF will not read it's value.

For more information: https://weblogs.asp.net/manavi/inheritance-mapping-strategies-with-entity-framework-code-first-ctp5-part-3-table-per-concrete-type-tpc-and-choosing-strategy-guidelines

Displaying the Error Messages in Laravel after being Redirected from controller

$validator = Validator::make($request->all(), [ 'email' => 'required|email', 'password' => 'required', ]);

if ($validator->fails()) { return $validator->errors(); }

How to change Android version and code version number?

You can define your versionName and versionCode in your module's build.gradle file like this :

android {
    compileSdkVersion 19
    buildToolsVersion "19.0.1"

    defaultConfig {
        minSdkVersion 8
        targetSdkVersion 19
        versionCode 1
        versionName "1.0"
    }
    .... //Other Configuration
}

Adding ID's to google map markers

JavaScript is a dynamic language. You could just add it to the object itself.

var marker = new google.maps.Marker(markerOptions);
marker.metadata = {type: "point", id: 1};

Also, because all v3 objects extend MVCObject(). You can use:

marker.setValues({type: "point", id: 1});
// or
marker.set("type", "point");
marker.set("id", 1);
var val = marker.get("id");

Disable/turn off inherited CSS3 transitions

You could also disinherit all transitions inside a containing element:

CSS:

.noTrans *{
-moz-transition: none;
-webkit-transition: none;
-o-transition: color 0 ease-in;
transition: none;
}

HTML:

<a href="#">Content</a>
<a href="#">Content</a>
<div class="noTrans">
<a href="#">Content</a>
</div>
<a href="#">Content</a>

iOS 7 - Status bar overlaps the view

For Navigation Bar :

Writing this code :

self.navigationController.navigationBar.translucent = NO;

just did the trick for me.

How to use cURL to get jSON data and decode the data?

You can use this:

curl_setopt_array($ch, $options);
$resultado = curl_exec($ch);
$info = curl_getinfo($ch);
print_r($info["url"]);

Import CSV file into SQL Server

Here's how I would solve it:

  1. Just Save your CSV File as a XLS Sheet in excel(By Doing so, you wouldn't have to worry about delimitiers. Excel's spreadsheet format will be read as a table and imported directly into a SQL Table)

  2. Import the File Using SSIS

  3. Write a Custom Script in the import manager to omit/modify the data you're looking for.(Or run a master script to scrutinize the data you're looking to remove)

Good Luck.

How do I write out a text file in C# with a code page other than UTF-8?

Simple!

System.IO.File.WriteAllText(path, text, Encoding.GetEncoding(28591));

How do I use 'git reset --hard HEAD' to revert to a previous commit?

First, it's always worth noting that git reset --hard is a potentially dangerous command, since it throws away all your uncommitted changes. For safety, you should always check that the output of git status is clean (that is, empty) before using it.

Initially you say the following:

So I know that Git tracks changes I make to my application, and it holds on to them until I commit the changes, but here's where I'm hung up:

That's incorrect. Git only records the state of the files when you stage them (with git add) or when you create a commit. Once you've created a commit which has your project files in a particular state, they're very safe, but until then Git's not really "tracking changes" to your files. (for example, even if you do git add to stage a new version of the file, that overwrites the previously staged version of that file in the staging area.)

In your question you then go on to ask the following:

When I want to revert to a previous commit I use: git reset --hard HEAD And git returns: HEAD is now at 820f417 micro

How do I then revert the files on my hard drive back to that previous commit?

If you do git reset --hard <SOME-COMMIT> then Git will:

  • Make your current branch (typically master) back to point at <SOME-COMMIT>.
  • Then make the files in your working tree and the index ("staging area") the same as the versions committed in <SOME-COMMIT>.

HEAD points to your current branch (or current commit), so all that git reset --hard HEAD will do is to throw away any uncommitted changes you have.

So, suppose the good commit that you want to go back to is f414f31. (You can find that via git log or any history browser.) You then have a few different options depending on exactly what you want to do:

  • Change your current branch to point to the older commit instead. You could do that with git reset --hard f414f31. However, this is rewriting the history of your branch, so you should avoid it if you've shared this branch with anyone. Also, the commits you did after f414f31 will no longer be in the history of your master branch.
  • Create a new commit that represents exactly the same state of the project as f414f31, but just adds that on to the history, so you don't lose any history. You can do that using the steps suggested in this answer - something like:

    git reset --hard f414f31
    git reset --soft HEAD@{1}
    git commit -m "Reverting to the state of the project at f414f31"
    

C# cannot convert method to non delegate type

As mentioned you need to use obj.getTile()

But, in this case I think you are looking to use a Property.

public class Pin
{
    private string title;

    public Pin() { }

    public setTitle(string title) {
        this.title = title;
    }

    public String Title
    {
        get { return title; }
    }
}

This will allow you to use

foreach (Pin obj in ClassListPin.pins)
{
     string t = obj.Title;
}

Changing tab bar item image and text color iOS

This Code works for Swift 4 if you want to change the image of Tab Bar Item when pressed. Copy and paste in the first viewDidLoad method that is hit in the project

   let arrayOfImageNameForSelectedState:[String] = ["Image1Color", "Image2Color","Image3Color"]
   let arrayOfImageNameForUnselectedState: [String] = ["Image1NoColor","Image2NoColor","Image3NoColor"]


    print(self.tabBarController?.tabBar.items?.count)

    if let count = self.tabBarController?.tabBar.items?.count {
        for i in 0...(count-1) {
            let imageNameForSelectedState   = arrayOfImageNameForSelectedState[i]
            print(imageNameForSelectedState)
            let imageNameForUnselectedState = arrayOfImageNameForUnselectedState[i]
            print(imageNameForUnselectedState)
            self.tabBarController?.tabBar.items?[i].selectedImage = UIImage(named: imageNameForSelectedState)?.withRenderingMode(.alwaysOriginal)
            self.tabBarController?.tabBar.items?[i].image = UIImage(named: imageNameForUnselectedState)?.withRenderingMode(.alwaysOriginal)
        }
    }

pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available

As Tokci said, it also works for Windows 7.

"Go with the mouse to the Windows Icon (lower left) and start typing "Anaconda". There should show up some matching entries. Select "Anaconda Prompt". A new command window, named "Anaconda Prompt" will open."

Then pip works.

The following also helped to import xgboost: https://www.youtube.com/watch?v=05djBSOs1FA

How to assign name for a screen?

As already stated, screen -S SESSIONTITLE works for starting a session with a title (SESSIONTITLE), but if you start a session and later decide to change its title. This can be accomplished by using the default key bindings:

Ctrl+a, A

Which prompts:

Set windows title to:SESSIONTITLE

Change SESSIONTITLE by backspacing and typing in the desired title. To confirm the name change and list all titles.

Ctrl+a, "

Angular 2 ngfor first, last, index loop

Check out this plunkr.

When you're binding to variables, you need to use the brackets. Also, you use the hashtag when you want to get references to elements in your html, not for declaring variables inside of templates like that.

<md-button-toggle *ngFor="let indicador of indicadores; let first = first;" [value]="indicador.id" [checked]="first"> 
...

Edit: Thanks to Christopher Moore: Angular exposes the following local variables:

  • index
  • first
  • last
  • even
  • odd

HttpListener Access Denied

You can start your application as administrator if you add Application Manifest to your project.

Just Add New Item to your project and select "Application Manifest File". Change the <requestedExecutionLevel> element to:

<requestedExecutionLevel level="requireAdministrator" uiAccess="false" />

Calling one method from another within same class in Python

To call the method, you need to qualify function with self.. In addition to that, if you want to pass a filename, add a filename parameter (or other name you want).

class MyHandler(FileSystemEventHandler):

    def on_any_event(self, event):
        srcpath = event.src_path
        print (srcpath, 'has been ',event.event_type)
        print (datetime.datetime.now())
        filename = srcpath[12:]
        self.dropbox_fn(filename) # <----

    def dropbox_fn(self, filename):  # <-----
        print('In dropbox_fn:', filename)

Why is null an object and what's the difference between null and undefined?

null is an object. Its type is null. undefined is not an object; its type is undefined.

Java code for getting current time

new Date().getTime() is bugged.

    Date date = new Date();
    System.out.println(date);
    System.out.println(date.getHours() + ":" + date.getMinutes() + ":" + date.getSeconds());
    long t1 = date.getTime();
    System.out.println((t1 / 1000 / 60 / 60) % 24 + ":" + (t1 / 1000 / 60) % 60 + ":" + (t1 / 1000) % 60);
    long t2 = System.currentTimeMillis();
    System.out.println((t2 / 1000 / 60 / 60) % 24 + ":" + (t2 / 1000 / 60) % 60 + ":" + (t2 / 1000) % 60);

It returns me the wrong time millis. System.currentTimeMillis() too. Since I ask the Date instance to tell me the corresponding time millis it must return the matching ones not others from a different time zone. Funny how deprecated methods are the only ones which return correct values.

How to make a JSON call to a url?

Because the URL isn't on the same domain as your website, you need to use JSONP.

For example: (In jQuery):

$.getJSON(
    'http://soundcloud.com/oembed?url=http%3A//soundcloud.com/forss/flickermood&format=js&callback=?', 
    function(data) { ... }
);

This works by creating a <script> tag like this one:

<script src="http://soundcloud.com/oembed?url=http%3A//soundcloud.com/forss/flickermood&format=js&callback=someFunction" type="text/javascript"></script>

Their server then emits Javascript that calls someFunction with the data to retrieve.
`someFunction is an internal callback generated by jQuery that then calls your callback.

How to send a POST request from node.js Express?

in your server side the code looks like:

var request = require('request');

app.post('/add', function(req, res){
  console.log(req.body);
  request.post(
    {
    url:'http://localhost:6001/add',
    json: {
      unit_name:req.body.unit_name,
      unit_price:req.body.unit_price
        },
    headers: {
        'Content-Type': 'application/json'
    }
    },
  function(error, response, body){
    // console.log(error);
    // console.log(response);
    console.log(body);
    res.send(body);
  });
  // res.send("body");
});

in receiving end server code looks like:

app.post('/add', function(req, res){
console.log('received request')
console.log(req.body);
let adunit = new AdUnit(req.body);
adunit.save()
.then(game => {
res.status(200).json({'adUnit':'AdUnit is added successfully'})
})
.catch(err => {
res.status(400).send('unable to save to database');
})
});

Schema is just two properties unit_name and unit_price.

Button text toggle in jquery

I preffer the following way, it can be used by any button.

<button class='pushme' data-default-text="PUSH ME" data-new-text="DON'T PUSH ME">PUSH ME</button>

$(".pushme").click(function () {
    var $element = $(this);
    $element.text(function(i, text) {
        return text == $element.data('default-text') ? $element.data('new-text')
                                                     : $element.data('default-text');
    });
});

demo

How to make a simple image upload using Javascript/HTML

<img id="output_image" height=50px width=50px\
<input type="file" accept="image/*" onchange="preview_image(event)">

<script type"text/javascript">
  function preview_image(event) {
    var reader = new FileReader();
    reader.onload = function(){
      var output = document.getElementById('output_image');
      output.src = reader.result;
    }
    reader.readAsDataURL(event.target.files[0]);
  }
</script>

jQuery get input value after keypress

Use .keyup instead of keypress.

Also use $(this).val() or just this.value to access the current input value.

DEMO here

Info about .keypress from jQuery docs,

The keypress event is sent to an element when the browser registers keyboard input. This is similar to the keydown event, except in the case of key repeats. If the user presses and holds a key, a keydown event is triggered once, but separate keypress events are triggered for each inserted character. In addition, modifier keys (such as Shift) trigger keydown events but not keypress events.

Android Firebase, simply get one child object's data

Firebase listeners fire for both the initial data and any changes.

If you're looking to synchronize the data in a collection, use ChildEventListener. If you're looking to synchronize a single object, use ValueEventListener. Note that in both cases you're not "getting" the data. You're synchronizing it, which means that the callback may be invoked multiple times: for the initial data and whenever the data gets updated.

This is covered in Firebase's quickstart guide for Android. The relevant code and quote:

FirebaseRef.child("message").addValueEventListener(new ValueEventListener() {
  @Override
  public void onDataChange(DataSnapshot snapshot) {
    System.out.println(snapshot.getValue());  //prints "Do you have data? You'll love Firebase."
  }
  @Override
  public void onCancelled(DatabaseError databaseError) {        
  }
});

In the example above, the value event will fire once for the initial state of the data, and then again every time the value of that data changes.

Please spend a few moments to go through that quick start. It shouldn't take more than 15 minutes and it will save you from a lot of head scratching and questions. The Firebase Android Guide is probably a good next destination, for this question specifically: https://firebase.google.com/docs/database/android/read-and-write

Why is it common to put CSRF prevention tokens in cookies?

Using a cookie to provide the CSRF token to the client does not allow a successful attack because the attacker cannot read the value of the cookie and therefore cannot put it where the server-side CSRF validation requires it to be.

The attacker will be able to cause a request to the server with both the auth token cookie and the CSRF cookie in the request headers. But the server is not looking for the CSRF token as a cookie in the request headers, it's looking in the payload of the request. And even if the attacker knows where to put the CSRF token in the payload, they would have to read its value to put it there. But the browser's cross-origin policy prevents reading any cookie value from the target website.

The same logic does not apply to the auth token cookie, because the server is expects it in the request headers and the attacker does not have to do anything special to put it there.

How to get time (hour, minute, second) in Swift 3 using NSDate?

For best useful I create this function:

func dateFormatting() -> String {
    let date = Date()
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "EEEE dd MMMM yyyy - HH:mm:ss"//"EE" to get short style
    let mydt = dateFormatter.string(from: date).capitalized

    return "\(mydt)"
}

You simply call it wherever you want like this:

print("Date = \(self.dateFormatting())")

this is the Output:

Date = Monday 15 October 2018 - 17:26:29

if want only the time simply change :

dateFormatter.dateFormat  = "HH:mm:ss"

and this is the output:

Date = 17:27:30

and that's it...

Print the contents of a DIV

Although this has been said by @gabe, If you are using jQuery, you can use my printElement plugin.

There's a sample here, and more information about the plugin here.

The usage is rather straight forward, just grab an element with a jQuery selector and print it:

$("#myDiv").printElement();

I hope it helps!

Python Pandas - Missing required dependencies ['numpy'] 1

I had the same issue with anaconda package, it got updated.

anaconda  {4.3.1 -> custom} ## I am not sure if this was the issue

Hit below command to know

conda list --revisions

what i did is just uninstall pandas with conda and re-install it

conda install pandas

Some new libs may also get installed with it.

It worked for me hope will do the same for you.

Adding a leading zero to some values in column in MySQL

Change the field back to numeric and use ZEROFILL to keep the zeros

or

use LPAD()

SELECT LPAD('1234567', 8, '0');

Java HTML Parsing

Jericho: http://jericho.htmlparser.net/docs/index.html

Easy to use, supports not well formed HTML, a lot of examples.

How to change value for innodb_buffer_pool_size in MySQL on Mac OS?

In the earlier versions of MySQL ( < 5.7.5 ) the only way to set

'innodb_buffer_pool_size'

variable was by writing it to my.cnf (for linux) and my.ini (for windows) under [mysqld] section :

[mysqld]

innodb_buffer_pool_size = 2147483648

You need to restart your mysql server to have it's effect in action.

UPDATE :

As of MySQL 5.7.5, the innodb_buffer_pool_size configuration option can be set dynamically using a SET statement, allowing you to resize the buffer pool without restarting the server. For example:

mysql> SET GLOBAL innodb_buffer_pool_size=402653184;

Reference : https://dev.mysql.com/doc/refman/5.7/en/innodb-buffer-pool-resize.html

How do I convert a C# List<string[]> to a Javascript array?

Here's how you accomplish that:

//View.cshtml
<script type="text/javascript">
    var arrayOfArrays = JSON.parse('@Html.Raw(Json.Encode(Model.Addresses))');
</script>

Java SSLException: hostname in certificate didn't match

I had similar problem. I was using Android's DefaultHttpClient. I have read that HttpsURLConnection can handle this kind of exception. So I created custom HostnameVerifier which uses the verifier from HttpsURLConnection. I also wrapped the implementation to custom HttpClient.

public class CustomHttpClient extends DefaultHttpClient {

public CustomHttpClient() {
    super();
    SSLSocketFactory socketFactory = SSLSocketFactory.getSocketFactory();
    socketFactory.setHostnameVerifier(new CustomHostnameVerifier());
    Scheme scheme = (new Scheme("https", socketFactory, 443));
    getConnectionManager().getSchemeRegistry().register(scheme);
}

Here is the CustomHostnameVerifier class:

public class CustomHostnameVerifier implements org.apache.http.conn.ssl.X509HostnameVerifier {

@Override
public boolean verify(String host, SSLSession session) {
    HostnameVerifier hv = HttpsURLConnection.getDefaultHostnameVerifier();
    return hv.verify(host, session);
}

@Override
public void verify(String host, SSLSocket ssl) throws IOException {
}

@Override
public void verify(String host, X509Certificate cert) throws SSLException {

}

@Override
public void verify(String host, String[] cns, String[] subjectAlts) throws SSLException {

}

}

How to redirect from one URL to another URL?

window.location.href = "URL2"

inside a JS block on the page or in an included file; that's assuming you really want to do it on the client. Usually, the server sends the redirect via a 300-series response.

How to recursively download a folder via FTP on Linux

ncftp -u <user> -p <pass> <server>
ncftp> mget directory

How to communicate between iframe and the parent site?

Use event.source.window.postMessage to send back to sender.

From Iframe

window.top.postMessage('I am Iframe', '*')
window.onmessage = (event) => {
    if (event.data === 'GOT_YOU_IFRAME') {
        console.log('Parent received successfully.')
    }
}

Then from parent say back.

window.onmessage = (event) => {
    event.source.window.postMessage('GOT_YOU_IFRAME', '*')
}

Displaying a webcam feed using OpenCV and Python

An update to show how to do it in the recent versions of OpenCV:

import cv2

cv2.namedWindow("preview")
vc = cv2.VideoCapture(0)

if vc.isOpened(): # try to get the first frame
    rval, frame = vc.read()
else:
    rval = False

while rval:
    cv2.imshow("preview", frame)
    rval, frame = vc.read()
    key = cv2.waitKey(20)
    if key == 27: # exit on ESC
        break

cv2.destroyWindow("preview")
vc.release()

It works in OpenCV-2.4.2 for me.

Can we have multiple <tbody> in same <table>?

Martin Joiner's problem is caused by a misunderstanding of the <caption> tag.

The <caption> tag defines a table caption.

The <caption> tag must be the first child of the <table> tag.

You can specify only one caption per table.

Also, note that the scope attribute should be placed on a <th> element and not on a <tr> element.

The proper way to write a multi-header multi-tbody table would be something like this :

_x000D_
_x000D_
<table id="dinner_table">_x000D_
    <caption>This is the only correct place to put a caption.</caption>_x000D_
    <tbody>_x000D_
        <tr class="header">_x000D_
            <th colspan="2" scope="col">First Half of Table (British Dinner)</th>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">1</th>_x000D_
            <td>Fish</td>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">2</th>_x000D_
            <td>Chips</td>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">3</th>_x000D_
            <td>Peas</td>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">4</th>_x000D_
            <td>Gravy</td>_x000D_
        </tr>_x000D_
    </tbody>_x000D_
    <tbody>_x000D_
        <tr class="header">_x000D_
            <th colspan="2" scope="col">Second Half of Table (Italian Dinner)</th>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">5</th>_x000D_
            <td>Pizza</td>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">6</th>_x000D_
            <td>Salad</td>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">7</th>_x000D_
            <td>Oil</td>_x000D_
        </tr>_x000D_
        <tr>_x000D_
            <th scope="row">8</th>_x000D_
            <td>Bread</td>_x000D_
        </tr>_x000D_
    </tbody>_x000D_
</table>
_x000D_
_x000D_
_x000D_

Structure padding and packing

There are no buts about it! Who want to grasp the subject must do the following ones,

How to find the socket connection state in C?

You should try to use: getpeername function.

now when the connection is down you will get in errno: ENOTCONN - The socket is not connected. which means for you DOWN.

else (if no other failures) there the return code will 0 --> which means UP.

resources: man page: http://man7.org/linux/man-pages/man2/getpeername.2.html

How to get current page URL in MVC 3

You could use the Request.RawUrl, Request.Url.OriginalString, Request.Url.ToString() or Request.Url.AbsoluteUri.

Android sample bluetooth code to send a simple string via bluetooth

private OutputStream outputStream;
private InputStream inStream;

private void init() throws IOException {
    BluetoothAdapter blueAdapter = BluetoothAdapter.getDefaultAdapter();
    if (blueAdapter != null) {
        if (blueAdapter.isEnabled()) {
            Set<BluetoothDevice> bondedDevices = blueAdapter.getBondedDevices();

            if(bondedDevices.size() > 0) {
                Object[] devices = (Object []) bondedDevices.toArray();
                BluetoothDevice device = (BluetoothDevice) devices[position];
                ParcelUuid[] uuids = device.getUuids();
                BluetoothSocket socket = device.createRfcommSocketToServiceRecord(uuids[0].getUuid());
                socket.connect();
                outputStream = socket.getOutputStream();
                inStream = socket.getInputStream();
            }

            Log.e("error", "No appropriate paired devices.");
        } else {
            Log.e("error", "Bluetooth is disabled.");
        }
    }
}

public void write(String s) throws IOException {
    outputStream.write(s.getBytes());
}

public void run() {
    final int BUFFER_SIZE = 1024;
    byte[] buffer = new byte[BUFFER_SIZE];
    int bytes = 0;
    int b = BUFFER_SIZE;

    while (true) {
        try {
            bytes = inStream.read(buffer, bytes, BUFFER_SIZE - bytes);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

How to escape special characters in building a JSON string?

Using template literals...

var json = `{"1440167924916":{"id":1440167924916,"type":"text","content":"It's a test!"}}`;

What is the simplest way to convert a Java string from all caps (words separated by underscores) to CamelCase (no word separators)?

A simple snnipet:

 public static String camelCase(String in) {
    if (in == null || in.length() < 1) { return ""; } //validate in
    String out = "";
    for (String part : in.toLowerCase().split("_")) {
        if (part.length() < 1) { //validate length
            continue;
        }
        out += part.substring(0, 1).toUpperCase();
        if (part.length() > 1) { //validate length
            out += part.substring(1);
        }
    }
    return out;
}

mysqld: Can't change dir to data. Server doesn't start

What I did (Windows 10) for a new installation:

  1. Start cmd in admin mode (run as administrator by hitting windows key, typing cmd, right clicking on it and selecting "Run as Administrator"

  2. Change into "MySQL Server X.Y" directory (for me the full path is C:\Program Files\MySQL\MySQL Server 5.7")

  3. using notepad create a my.ini with a mysqld section that points at your data directory

    [mysqld]
    datadir="X:\Your Directory Path and Name"
    
  4. created the directory identified in my.ini above.

  5. change into bin Directory under server directory and execute: mysqld --initialize

  6. Once complete, started the service and it came up fine.

How can I configure Logback to log different levels for a logger to different destinations?

Solution based on configuration only, with a ThresoldFilter and LevelFilters to keep things really simple to understand :

<configuration>
    <appender name="STDERR" class="ch.qos.logback.core.ConsoleAppender">
        <target>System.err</target>
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
          <level>WARN</level>
        </filter>
        <encoder>
            <pattern>%date %level [%thread] %logger %msg%n</pattern>
        </encoder>
    </appender>

    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <target>System.out</target>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
          <level>DEBUG</level>
          <onMatch>ACCEPT</onMatch>
        </filter>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
          <level>INFO</level>
          <onMatch>ACCEPT</onMatch>
        </filter>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
          <level>TRACE</level>
          <onMatch>ACCEPT</onMatch>
        </filter>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
          <level>WARN</level>
          <onMatch>DENY</onMatch>
        </filter>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
          <level>ERROR</level>
          <onMatch>DENY</onMatch>
        </filter>
        <encoder>
            <pattern>%date %level [%thread] %logger %msg%n</pattern>
        </encoder>
    </appender>

    <root level="INFO">
        <appender-ref ref="STDOUT" />
        <appender-ref ref="STDERR" />
    </root>
</configuration>

Convert an enum to List<string>

Use Enum's static method, GetNames. It returns a string[], like so:

Enum.GetNames(typeof(DataSourceTypes))

If you want to create a method that does only this for only one type of enum, and also converts that array to a List, you can write something like this:

public List<string> GetDataSourceTypes()
{
    return Enum.GetNames(typeof(DataSourceTypes)).ToList();
}

You will need Using System.Linq; at the top of your class to use .ToList()