Programs & Examples On #Cyclic graph

How to find file accessed/created just few minutes ago

Simply specify whether you want the time to be greater, smaller, or equal to the time you want, using, respectively:

find . -cmin +<time>
find . -cmin -<time>
find . -cmin  <time>

In your case, for example, the files with last edition in a maximum of 5 minutes, are given by:

find . -cmin -5

Truncating all tables in a Postgres database

Guys the better and clean way is to :

1) Create Schema dump of database (--schema-only) pg_dump mydb -s > schema.sql

2) Drop database drop database mydb;

3) Create Database create database mydb;

4) Import Schema psql mydb < schema.sql

It´s work for me!

Have a nice day. Hiram Walker

All possible array initialization syntaxes

Enumerable.Repeat(String.Empty, count).ToArray()

Will create array of empty strings repeated 'count' times. In case you want to initialize array with same yet special default element value. Careful with reference types, all elements will refer same object.

What's the difference between eval, exec, and compile?

  1. exec is not an expression: a statement in Python 2.x, and a function in Python 3.x. It compiles and immediately evaluates a statement or set of statement contained in a string. Example:

     exec('print(5)')           # prints 5.
     # exec 'print 5'     if you use Python 2.x, nor the exec neither the print is a function there
     exec('print(5)\nprint(6)')  # prints 5{newline}6.
     exec('if True: print(6)')  # prints 6.
     exec('5')                 # does nothing and returns nothing.
    
  2. eval is a built-in function (not a statement), which evaluates an expression and returns the value that expression produces. Example:

     x = eval('5')              # x <- 5
     x = eval('%d + 6' % x)     # x <- 11
     x = eval('abs(%d)' % -100) # x <- 100
     x = eval('x = 5')          # INVALID; assignment is not an expression.
     x = eval('if 1: x = 4')    # INVALID; if is a statement, not an expression.
    
  3. compile is a lower level version of exec and eval. It does not execute or evaluate your statements or expressions, but returns a code object that can do it. The modes are as follows:

  4. compile(string, '', 'eval') returns the code object that would have been executed had you done eval(string). Note that you cannot use statements in this mode; only a (single) expression is valid.

  5. compile(string, '', 'exec') returns the code object that would have been executed had you done exec(string). You can use any number of statements here.

  6. compile(string, '', 'single') is like the exec mode but expects exactly one expression/statement, eg compile('a=1 if 1 else 3', 'myf', mode='single')

With Spring can I make an optional path variable?

Check this Spring 3 WebMVC - Optional Path Variables. It shows an article of making an extension to AntPathMatcher to enable optional path variables and might be of help. All credits to Sebastian Herold for posting the article.

VBA Go to last empty row

This does it:

Do
   c = c + 1
Loop While Cells(c, "A").Value <> ""

'prints the last empty row
Debug.Print c

What is the difference between procedural programming and functional programming?

A functional language (ideally) allows you to write a mathematical function, i.e. a function that takes n arguments and returns a value. If the program is executed, this function is logically evaluated as needed.1

A procedural language, on the other hand, performs a series of sequential steps. (There's a way of transforming sequential logic into functional logic called continuation passing style.)

As a consequence, a purely functional program always yields the same value for an input, and the order of evaluation is not well-defined; which means that uncertain values like user input or random values are hard to model in purely functional languages.


1 As everything else in this answer, that’s a generalisation. This property, evaluating a computation when its result is needed rather than sequentially where it’s called, is known as “laziness”. Not all functional languages are actually universally lazy, nor is laziness restricted to functional programming. Rather, the description given here provides a “mental framework” to think about different programming styles that are not distinct and opposite categories but rather fluid ideas.

Executing a batch script on Windows shutdown

Well, its an easy way of doing some registry changes: I tried this on 2008 r2 and 2016 servers.

Things need to be done:

  1. Create a text file "regedit.txt"
  2. Paste the following code in it:
Windows Registry Editor Version 5.00 

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Scripts]

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Scripts\Shutdown] 

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\Scripts\Shutdown]     

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Scripts\Shutdown\0]  
"GPO-ID"="LocalGPO"    
"SOM-ID"="Local"    
"FileSysPath"="C:\\Windows\\System32\\GroupPolicy\\Machine"    
"DisplayName"="Local Group Policy"    
"GPOName"="Local Group Policy"    

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\State\Machine\Scripts\Shutdown\0\0]    
"Script"="terminate_script.bat"    
"Parameters"=""    
"ExecTime"=hex(b):00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00    

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\Scripts\Shutdown\0]
"GPO-ID"="LocalGPO"    
"SOM-ID"="Local"    
"FileSysPath"="C:\\Windows\\System32\\GroupPolicy\\Machine"    
"DisplayName"="Local Group Policy"    
"GPOName"="Local Group Policy"

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy\Scripts\Shutdown\0\0]    
"Script"="terminate_script.bat"    
"Parameters"=""
"IsPowershell"=dword:00000000
"ExecTime"=hex(b):00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00
  1. Save this file as regedit.reg extension

  2. Run it on any command line using below command:

    regedit.exe /s regedit.reg
    

Finding rows that don't contain numeric data in Oracle

To get an indicator:

DECODE( TRANSLATE(your_number,' 0123456789',' ')

e.g.

SQL> select DECODE( TRANSLATE('12345zzz_not_numberee',' 0123456789',' '), NULL, 'number','contains char')
 2 from dual
 3 /

"contains char"

and

SQL> select DECODE( TRANSLATE('12345',' 0123456789',' '), NULL, 'number','contains char')
 2 from dual
 3 /

"number"

and

SQL> select DECODE( TRANSLATE('123405',' 0123456789',' '), NULL, 'number','contains char')
 2 from dual
 3 /

"number"

Oracle 11g has regular expressions so you could use this to get the actual number:

SQL> SELECT colA
  2  FROM t1
  3  WHERE REGEXP_LIKE(colA, '[[:digit:]]');

COL1
----------
47845
48543
12
...

If there is a non-numeric value like '23g' it will just be ignored.

How to close a GUI when I push a JButton?

Add your button:

JButton close = new JButton("Close");

Add an ActionListener:

close.addActionListner(new CloseListener());

Add a class for the Listener implementing the ActionListener interface and override its main function:

private class CloseListener implements ActionListener{
    @Override
    public void actionPerformed(ActionEvent e) {
        //DO SOMETHING
        System.exit(0);
    }
}

This might be not the best way, but its a point to start. The class for example can be made public and not as a private class inside another one.

Parse DateTime string in JavaScript

We use this code to check if the string is a valid date

var dt = new Date(txtDate.value)
if (isNaN(dt))

state machines tutorials

I prefer using function pointers over gigantic switch statements, but in contrast to qrdl's answer I normally don't use explicit return codes or transition tables.

Also, in most cases you'll want a mechanism to pass along additional data. Here's an example state machine:

#include <stdio.h>

struct state;
typedef void state_fn(struct state *);

struct state
{
    state_fn * next;
    int i; // data
};

state_fn foo, bar;

void foo(struct state * state)
{
    printf("%s %i\n", __func__, ++state->i);
    state->next = bar;
}

void bar(struct state * state)
{
    printf("%s %i\n", __func__, ++state->i);
    state->next = state->i < 10 ? foo : 0;
}

int main(void)
{
    struct state state = { foo, 0 };
    while(state.next) state.next(&state);
}

Is there a kind of Firebug or JavaScript console debug for Android?

Try js-mobile-console

MobileConsole can be embedded within any page for debugging. It will catch errors and behave exactly as the native JavaScript console in the browser. It also outputs all the logs you've written via an API of window.console.

Datetime in C# add days

Use this:

DateTime dateTime =  DateTime.Now;
DateTime? newDateTime = null;
TimeSpan numberOfDays = new TimeSpan(2, 0, 0, 0, 0);
newDateTime = dateTime.Add(numberOfDays);

How to convert FileInputStream to InputStream?

FileInputStream is an inputStream.

FileInputStream fis = new FileInputStream("c://filename");
InputStream is = fis;
fis.close();  
return is;

Of course, this will not do what you want it to do; the stream you return has already been closed. Just return the FileInputStream and be done with it. The calling code should close it.

HTML5 Video Stop onClose

Starting Video with different browsers

For Opera 12

window.navigator.getUserMedia(param, function(stream) {
                            video.src =window.URL.createObjectURL(stream);
                        }, videoError );

For Firefox Nightly 18.0

window.navigator.mozGetUserMedia(param, function(stream) {
                            video.mozSrcObject = stream;
                        }, videoError );

For Chrome 22

window.navigator.webkitGetUserMedia(param, function(stream) {
                            video.src =window.webkitURL.createObjectURL(stream);
                        },  videoError );

Stopping video with different browsers

For Opera 12

video.pause();
video.src=null;

For Firefox Nightly 18.0

video.pause();
video.mozSrcObject=null;

For Chrome 22

video.pause();
video.src="";

The located assembly's manifest definition does not match the assembly reference

I had similar problem but no answer worked for me.

The solution that worked for me was removing publicKeyToken part from project file(YourProject.csproj) manually.

Previously it had been:

<Reference Include="Utility, Version=0.0.0.0, Culture=neutral, PublicKeyToken=e71b9933bfee3534, processorArchitecture=MSIL">
  <SpecificVersion>False</SpecificVersion>
  <HintPath>dlls\Utility.dll</HintPath>
</Reference>

After change it was:

<Reference Include="Utility, Version=1.0.1.100, Culture=neutral, processorArchitecture=MSIL">
  <SpecificVersion>False</SpecificVersion>
  <HintPath>dlls\Utility.dll</HintPath>
</Reference>

Be sure that SpecificVersion is False.

How can I tell gcc not to inline a function?

GCC has a switch called

-fno-inline-small-functions

So use that when invoking gcc. But the side effect is that all other small functions are also non-inlined.

How to cancel a Task in await?

I just want to add to the already accepted answer. I was stuck on this, but I was going a different route on handling the complete event. Rather than running await, I add a completed handler to the task.

Comments.AsAsyncAction().Completed += new AsyncActionCompletedHandler(CommentLoadComplete);

Where the event handler looks like this

private void CommentLoadComplete(IAsyncAction sender, AsyncStatus status )
{
    if (status == AsyncStatus.Canceled)
    {
        return;
    }
    CommentsItemsControl.ItemsSource = Comments.Result;
    CommentScrollViewer.ScrollToVerticalOffset(0);
    CommentScrollViewer.Visibility = Visibility.Visible;
    CommentProgressRing.Visibility = Visibility.Collapsed;
}

With this route, all the handling is already done for you, when the task is cancelled it just triggers the event handler and you can see if it was cancelled there.

MySQL my.ini location

You can find the my.ini file in windows at this location- C:\ProgramData\MySQL\MySQL Server 5.6

the ProgramData folder is a hidden folder, so make the according setting to see that folder. And open my.ini file as an administrator to edit and then save that.

How to retrieve data from sqlite database in android and display it in TextView

TextView tekst = (TextView) findViewById(R.id.editText1); 

You cannot cast EditText to TextView.

How to split a python string on new line characters

? Splitting line in Python:

Have you tried using str.splitlines() method?:

From the docs:

str.splitlines([keepends])

Return a list of the lines in the string, breaking at line boundaries. Line breaks are not included in the resulting list unless keepends is given and true.

For example:

>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()
['Line 1', '', 'Line 3', 'Line 4']

>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines(True)
['Line 1\n', '\n', 'Line 3\r', 'Line 4\r\n']

Which delimiters are considered?

This method uses the universal newlines approach to splitting lines.

The main difference between Python 2.X and Python 3.X is that the former uses the universal newlines approach to splitting lines, so "\r", "\n", and "\r\n" are considered line boundaries for 8-bit strings, while the latter uses a superset of it that also includes:

  • \v or \x0b: Line Tabulation (added in Python 3.2).
  • \f or \x0c: Form Feed (added in Python 3.2).
  • \x1c: File Separator.
  • \x1d: Group Separator.
  • \x1e: Record Separator.
  • \x85: Next Line (C1 Control Code).
  • \u2028: Line Separator.
  • \u2029: Paragraph Separator.

splitlines VS split:

Unlike str.split() when a delimiter string sep is given, this method returns an empty list for the empty string, and a terminal line break does not result in an extra line:

>>> ''.splitlines()
[]

>>> 'Line 1\n'.splitlines()
['Line 1']

While str.split('\n') returns:

>>> ''.split('\n')
['']

>>> 'Line 1\n'.split('\n')
['Line 1', '']

?? Removing additional whitespace:

If you also need to remove additional leading or trailing whitespace, like spaces, that are ignored by str.splitlines(), you could use str.splitlines() together with str.strip():

>>> [str.strip() for str in 'Line 1  \n  \nLine 3 \rLine 4 \r\n'.splitlines()]
['Line 1', '', 'Line 3', 'Line 4']

? Removing empty strings (''):

Lastly, if you want to filter out the empty strings from the resulting list, you could use filter():

>>> # Python 2.X:
>>> filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines())
['Line 1', 'Line 3', 'Line 4']

>>> # Python 3.X:
>>> list(filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()))
['Line 1', 'Line 3', 'Line 4']

Additional comment regarding the original question:

As the error you posted indicates and Burhan suggested, the problem is from the print. There's a related question about that could be useful to you: UnicodeEncodeError: 'charmap' codec can't encode - character maps to <undefined>, print function

PHP shell_exec() vs exec()

Here are the differences. Note the newlines at the end.

> shell_exec('date')
string(29) "Wed Mar  6 14:18:08 PST 2013\n"
> exec('date')
string(28) "Wed Mar  6 14:18:12 PST 2013"

> shell_exec('whoami')
string(9) "mark\n"
> exec('whoami')
string(8) "mark"

> shell_exec('ifconfig')
string(1244) "eth0      Link encap:Ethernet  HWaddr 10:bf:44:44:22:33  \n          inet addr:192.168.0.90  Bcast:192.168.0.255  Mask:255.255.255.0\n          inet6 addr: fe80::12bf:ffff:eeee:2222/64 Scope:Link\n          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1\n          RX packets:16264200 errors:0 dropped:1 overruns:0 frame:0\n          TX packets:7205647 errors:0 dropped:0 overruns:0 carrier:0\n          collisions:0 txqueuelen:1000 \n          RX bytes:13151177627 (13.1 GB)  TX bytes:2779457335 (2.7 GB)\n"...
> exec('ifconfig')
string(0) ""

Note that use of the backtick operator is identical to shell_exec().

Update: I really should explain that last one. Looking at this answer years later even I don't know why that came out blank! Daniel explains it above -- it's because exec only returns the last line, and ifconfig's last line happens to be blank.

Using CSS td width absolute, position

You're better off using table-layout: fixed

Auto is the default value and with large tables can cause a bit of client side lag as the browser iterates through it to check all the sizes fit.

Fixed is far better and renders quicker to the page. The structure of the table is dependent on the tables overall width and the width of each of the columns.

Here it is applied to the original example: JSFIDDLE, You'll note that the remaining columns are crushed and overlapping their content. We can fix that with some more CSS (all I've had to do is add a class to the first TR):

    table {
        width: 100%;
        table-layout: fixed;
    }

    .header-row > td {
        width: 100px;
    }

    td.rhead {
        width: 300px
    }

Seen in action here: JSFIDDLE

How to make a JSONP request from Javascript without JQuery?

/**
 * Get JSONP data for cross-domain AJAX requests
 * @private
 * @link http://cameronspear.com/blog/exactly-what-is-jsonp/
 * @param  {String} url      The URL of the JSON request
 * @param  {String} callback The name of the callback to run on load
 */
var loadJSONP = function ( url, callback ) {

    // Create script with url and callback (if specified)
    var ref = window.document.getElementsByTagName( 'script' )[ 0 ];
    var script = window.document.createElement( 'script' );
    script.src = url + (url.indexOf( '?' ) + 1 ? '&' : '?') + 'callback=' + callback;

    // Insert script tag into the DOM (append to <head>)
    ref.parentNode.insertBefore( script, ref );

    // After the script is loaded (and executed), remove it
    script.onload = function () {
        this.remove();
    };

};

/** 
 * Example
 */

// Function to run on success
var logAPI = function ( data ) {
    console.log( data );
}

// Run request
loadJSONP( 'http://api.petfinder.com/shelter.getPets?format=json&key=12345&shelter=AA11', 'logAPI' );

Does Python have a string 'contains' substring method?

You can use the in operator:

if "blah" not in somestring: 
    continue

Best timing method in C?

I think this should work:

#include <time.h>

clock_t start = clock(), diff;
ProcessIntenseFunction();
diff = clock() - start;

int msec = diff * 1000 / CLOCKS_PER_SEC;
printf("Time taken %d seconds %d milliseconds", msec/1000, msec%1000);

How to ping multiple servers and return IP address and Hostnames using batch script?

the problem with ping is if the host is not alive often your local machine will return an answer that the pinged host is not available, thus the errorcode of ping will be 0 and your code will run in error because not recognizing the down state.

better do it this way

ping -n 4 %1 | findstr TTL
if %errorlevel%==0 (goto :eof) else (goto :error)

this way you look for a typical string ttl which is always in the well done ping result and check error on this findstr instead of irritating ping

overall this looks like this:

@echo off
SetLocal


set log=path/to/logfile.txt
set check=path/to/checkfile.txt

:start
echo. some echo date >>%log%

:check
for /f %%r in (%check%) do (call :ping %%r)
goto :eof

:ping
ping -n 4 %1 | findstr TTL
if %errorlevel%==0 (goto :eof) else (goto :error)

:error
echo. some errormessage to >>%log%
echo. some blat to mail?

:eof
echo. some good message to >>%log%

How do I center text horizontally and vertically in a TextView?

Use android:textAlignment="center"

       <TextView
        android:text="HOW WAS\nYOUR\nDAY?"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAlignment="center"
        android:id="@+id/textView5"
         />

Can't find SDK folder inside Android studio path, and SDK manager not opening

I had to open Android studio and go through the wizard. Android studio will install the SDK for you.

How do you connect to a MySQL database using Oracle SQL Developer?

Under Tools > Preferences > Databases there is a third party JDBC driver path that must be setup. Once the driver path is setup a separate 'MySQL' tab should appear on the New Connections dialog.

Note: This is the same jdbc connector that is available as a JAR download from the MySQL website.

How to get javax.comm API?

Oracle Java Communications API Reference - http://www.oracle.com/technetwork/java/index-jsp-141752.html

Official 3.0 Download (Solarix, Linux) - http://www.oracle.com/technetwork/java/javasebusiness/downloads/java-archive-downloads-misc-419423.html

Unofficial 2.0 Download (All): http://www.java2s.com/Code/Jar/c/Downloadcomm20jar.htm

Unofficial 2.0 Download (Windows installer) - http://kishor15389.blogspot.hk/2011/05/how-to-install-java-communications.html

In order to ensure there is no compilation error, place the file on your classpath when compiling (-cp command-line option, or check your IDE documentation).

Python dictionary: Get list of values for list of keys

new_dict = {x: v for x, v in mydict.items() if x in mykeys}

RAW POST using cURL in PHP

Implementation with Guzzle library:

use GuzzleHttp\Client;
use GuzzleHttp\RequestOptions;

$httpClient = new Client();

$response = $httpClient->post(
    'https://postman-echo.com/post',
    [
        RequestOptions::BODY => 'POST raw request content',
        RequestOptions::HEADERS => [
            'Content-Type' => 'application/x-www-form-urlencoded',
        ],
    ]
);

echo(
    $response->getBody()->getContents()
);

PHP CURL extension:

$curlHandler = curl_init();

curl_setopt_array($curlHandler, [
    CURLOPT_URL => 'https://postman-echo.com/post',
    CURLOPT_RETURNTRANSFER => true,

    /**
     * Specify POST method
     */
    CURLOPT_POST => true,

    /**
     * Specify request content
     */
    CURLOPT_POSTFIELDS => 'POST raw request content',
]);

$response = curl_exec($curlHandler);

curl_close($curlHandler);

echo($response);

Source code

Getting the current date in visual Basic 2008

If you need exact '/' delimiters, for example: 09/20/2013 rather than 09.20.2013, use escape sequence '/':

Dim regDate As Date = Date.Now()
Dim strDate As String = regDate.ToString("MM\/dd\/yyyy")

Numeric for loop in Django templates

My take on this issue, i think is the nicest. I keep a my_filters.py on the templatetags directory.

@register.filter(name='times') 
def times(number):
    return range(number)

And you would use like this:

{% load my_filters %}
{% for i in 15|times %}
    <li>Item</li>
{% endfor %}

How can I use a custom font in Java?

If you want to use the font to draw with graphics2d or similar, this works:

InputStream stream = ClassLoader.getSystemClassLoader().getResourceAsStream("roboto-bold.ttf")
Font font = Font.createFont(Font.TRUETYPE_FONT, stream).deriveFont(48f)

How to add facebook share button on my website?

Share Dialog without requiring Facebook login

You can Trigger a Share Dialog using the FB.ui function with the share method parameter to share a link. This dialog is available in the Facebook SDKs for JavaScript, iOS, and Android by performing a full redirect to a URL.

You can trigger this call:

FB.ui({
  method: 'share',
  href: 'https://developers.facebook.com/docs/', // Link to share
}, function(response){});

You can also include open graph meta tags on the page at this URL to customise the story that is shared back to Facebook.

Note that response.error_message will appear only if someone using your app has authenticated your app with Facebook Login.

Also you can directly share link with call by having Javascript Facebook SDK.

https://www.facebook.com/dialog/share&app_id=145634995501895&display=popup&href=https%3A%2F%2Fdevelopers.facebook.com%2Fdocs%2F&redirect_uri=https%3A%2F%2Fdevelopers.facebook.com%2Ftools%2Fexplorer

https://www.facebook.com/dialog/share&app_id={APP_ID}&display=popup&href={LINK_TO_SHARE}&redirect_uri={REDIRECT_AFTER_SHARE}
  • app_id => Your app's unique identifier. (Required.)

  • redirect_uri => The URL to redirect to after a person clicks a button on the dialog. Required when using URL redirection.

  • display => Determines how the dialog is rendered.

If you are using the URL redirect dialog implementation, then this will be a full page display, shown within Facebook.com. This display type is called page. If you are using one of our iOS or Android SDKs to invoke the dialog, this is automatically specified and chooses an appropriate display type for the device. If you are using the Facebook SDK for JavaScript, this will default to a modal iframe type for people logged into your app or async when using within a game on Facebook.com, and a popup window for everyone else. You can also force the popup or page types when using the Facebook SDK for JavaScript, if necessary. Mobile web apps will always default to the touch display type. share Parameters

  • href => The link attached to this post. Required when using method share. Include open graph meta tags in the page at this URL to customize the story that is shared.

Reset Windows Activation/Remove license key

On Windows XP -

  1. Reboot into "Safe mode with Command Prompt"
  2. Type "explorer" in the command prompt that comes up and push [Enter]
  3. Click on Start>Run, and type the following :

    rundll32.exe syssetup,SetupOobeBnk

Reboot, and login as normal.

This will reset the 30 day timer for activation back to 30 days so you can enter in the key normally.

EC2 instance has no public DNS

For me problem was in subnet settings.

  1. Open https://console.aws.amazon.com/vpc
  2. Go to subnets in left menu
  3. Choose your subnet
  4. Modify auto-assigning IP settings to enable

How to retrieve an element from a set without removing it?

What I usually do for small collections is to create kind of parser/converter method like this

def convertSetToList(setName):
return list(setName)

Then I can use the new list and access by index number

userFields = convertSetToList(user)
name = request.json[userFields[0]]

As a list you will have all the other methods that you may need to work with

javascript cell number validation

function IsMobileNumber(txtMobId) {
    var mob = /^[1-9]{1}[0-9]{9}$/;
    var txtMobile = document.getElementById(txtMobId);
    if (mob.test(txtMobile.value) == false) {
        alert("Please enter valid mobile number.");
        txtMobile.focus();
        return false;
    }
    return true;
}

Calling Validation Mobile Number Function HTML Code -

List of all unique characters in a string?

if the result does not need to be order-preserving, then you can simply use a set

>>> ''.join(set( "aaabcabccd"))
'acbd'
>>>

How to initialize a two-dimensional array in Python?

Incorrect Approach: [[None*m]*n]

>>> m, n = map(int, raw_input().split())
5 5
>>> x[0][0] = 34
>>> x
[[34, None, None, None, None], [34, None, None, None, None], [34, None, None, None, None], [34, None, None, None, None], [34, None, None, None, None]]
>>> id(x[0][0])
140416461589776
>>> id(x[3][0])
140416461589776

With this approach, python does not allow creating different address space for the outer columns and will lead to various misbehaviour than your expectation.

Correct Approach but with exception:

y = [[0 for i in range(m)] for j in range(n)]
>>> id(y[0][0]) == id(y[1][0])
False

It is good approach but there is exception if you set default value to None

>>> r = [[None for i in range(5)] for j in range(5)]
>>> r
[[None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None], [None, None, None, None, None]]
>>> id(r[0][0]) == id(r[2][0])
True

So set your default value properly using this approach.

Absolute correct:

Follow the mike's reply of double loop.

How to check whether a string is Base64 encoded or not

This works in Python:

def is_base64(string):
    if len(string) % 4 == 0 and re.test('^[A-Za-z0-9+\/=]+\Z', string):
        return(True)
    else:
        return(False)

Using Node.JS, how do I read a JSON file into (server) memory?

Using fs-extra package is quite simple:

Sync:

const fs = require('fs-extra')

const packageObj = fs.readJsonSync('./package.json')
console.log(packageObj.version) 

Async:

const fs = require('fs-extra')

const packageObj = await fs.readJson('./package.json')
console.log(packageObj.version) 

Content Security Policy: The page's settings blocked the loading of a resource

You can disable them in your browser.

Firefox

Type about:config in the Firefox address bar and find security.csp.enable and set it to false.

Chrome

You can install the extension called Disable Content-Security-Policy to disable CSP.

What is The difference between ListBox and ListView

A ListView let you define a set of views for it and gives you a native way (WPF binding support) to control the display of ListView by using defined views.

Example:

XAML

<ListView ItemsSource="{Binding list}" Name="listv" MouseEnter="listv_MouseEnter" MouseLeave="listv_MouseLeave">
        <ListView.Resources>
            <GridView x:Key="one">
                <GridViewColumn Header="ID" >
                    <GridViewColumn.CellTemplate>
                        <DataTemplate>
                            <TextBlock Text="{Binding id}" />
                        </DataTemplate>
                    </GridViewColumn.CellTemplate>
                </GridViewColumn>
                <GridViewColumn Header="Name" >
                    <GridViewColumn.CellTemplate>
                        <DataTemplate>
                            <TextBlock Text="{Binding name}" />
                        </DataTemplate>
                    </GridViewColumn.CellTemplate>
                </GridViewColumn>
            </GridView>
            <GridView x:Key="two">                    
                <GridViewColumn Header="Name" >
                    <GridViewColumn.CellTemplate>
                        <DataTemplate>
                            <TextBlock Text="{Binding name}" />
                        </DataTemplate>
                    </GridViewColumn.CellTemplate>
                </GridViewColumn>
            </GridView>
        </ListView.Resources>
        <ListView.Style>
            <Style TargetType="ListView">
                <Style.Triggers>
                    <DataTrigger Binding="{Binding ViewType}" Value="1">
                        <Setter Property="View" Value="{StaticResource one}" />
                    </DataTrigger>
                </Style.Triggers>
                <Setter Property="View" Value="{StaticResource two}" />
            </Style>
        </ListView.Style>  

Code Behind:

private int viewType;

public int ViewType
{
    get { return viewType; }
    set 
    { 
        viewType = value;
        UpdateProperty("ViewType");
    }
}        

private void listv_MouseEnter(object sender, MouseEventArgs e)
{
    ViewType = 1;
}

private void listv_MouseLeave(object sender, MouseEventArgs e)
{
    ViewType = 2;
}

OUTPUT:

Normal View: View 2 in above XAML

Normal

MouseOver View: View 1 in above XAML

Mouse Over

If you try to achieve above in a ListBox, probably you'll end up writing a lot more code forControlTempalate/ItemTemplate of ListBox.

Using Excel as front end to Access database (with VBA)

I did it in one project of mine. I used MDB to store the data about bills and used Excel to render them, giving the user the possibility to adapt it.

In this case the best solution is:

  1. Not to use any ADO/DAO in Excel. I implemented everything as public functions in MDB modules and called them directly from Excel. You can return even complex data objects, like arrays of strings etc by calling MDB functions with necessary arguments. This is similar to client/server architecture of modern web applications: you web application just does the rendering and user interaction, database and middle tier is then on the server side.

  2. Use Excel forms for user interaction and for data visualisation.

  3. I usually have a very last sheet with some names regions for settings: the path to MDB files, some settings (current user, password if needed etc.) -- so you can easily adapt your Excel implementation to different location of you "back-end" data.

How to Access Hive via Python?

I assert that you are using HiveServer2, which is the reason that makes the code doesn't work.

You may use pyhs2 to access your Hive correctly and the example code like that:

import pyhs2

with pyhs2.connect(host='localhost',
               port=10000,
               authMechanism="PLAIN",
               user='root',
               password='test',
               database='default') as conn:
    with conn.cursor() as cur:
        #Show databases
        print cur.getDatabases()

        #Execute query
        cur.execute("select * from table")

        #Return column info from query
        print cur.getSchema()

        #Fetch table results
        for i in cur.fetch():
            print i

Attention that you may install python-devel.x86_64 cyrus-sasl-devel.x86_64 before installing pyhs2 with pip.

Wish this can help you.

Reference: https://cwiki.apache.org/confluence/display/Hive/Setting+Up+HiveServer2#SettingUpHiveServer2-PythonClientDriver

How connect Postgres to localhost server using pgAdmin on Ubuntu?

First you should change the password using terminal. (username is postgres)

postgres=# \password postgres

Then you will be prompted to enter the password and confirm it.

Now you will be able to connect using pgadmin with the new password.

Session 'app': Error Installing APK

Make sure that project name doesn't contain special character.

Check if key exists in JSON object using jQuery

if you have an array

var subcategories=[{name:"test",desc:"test"}];

function hasCategory(nameStr) {
        for(let i=0;i<subcategories.length;i++){
            if(subcategories[i].name===nameStr){
                return true;
            }
        }
        return false;
    }

if you have an object

var category={name:"asd",test:""};

if(category.hasOwnProperty('name')){//or category.name!==undefined
   return true;
}else{
   return false;
}

How to compare two maps by their values

The result of equals in your example is obviously false because you are comparing the map a with some values in it with an empty map b (probably a copy and paste error). I recommend to use proper variable names (so you can avoid these kinds of errors) and make use of generics, too.

    Map<String, String> first = new HashMap<String, String>();
    first.put("f"+"oo", "bar"+"bar");
    first.put("fo"+"o", "bar"+"bar");

    Map second = new HashMap();
    second.put("f"+"oo", "bar"+"bar");
    second.put("fo"+"o", "bar"+"bar");

    System.out.println("equals: " + first.equals(second));

The concatenation of your strings doesn't have any effect because it will be done at compile time.

PHP multidimensional array search by value

function searchForId($id, $array) {
   foreach ($array as $key => $val) {
       if ($val['uid'] === $id) {
           return $key;
       }
   }
   return null;
}

This will work. You should call it like this:

$id = searchForId('100', $userdb);

It is important to know that if you are using === operator compared types have to be exactly same, in this example you have to search string or just use == instead ===.

Based on angoru answer. In later versions of PHP (>= 5.5.0) you can use one-liner.

$key = array_search('100', array_column($userdb, 'uid'));

Here is documentation: http://php.net/manual/en/function.array-column.php.

PHP exec() vs system() vs passthru()

It really all comes down to how you want to handle output that the command might return and whether you want your PHP script to wait for the callee program to finish or not.

  • exec executes a command and passes output to the caller (or returns it in an optional variable).

  • passthru is similar to the exec() function in that it executes a command . This function should be used in place of exec() or system() when the output from the Unix command is binary data which needs to be passed directly back to the browser.

  • system executes an external program and displays the output, but only the last line.

If you need to execute a command and have all the data from the command passed directly back without any interference, use the passthru() function.

List of strings to one string

string.Concat(los.ToArray());

If you just want to concatenate the strings then use string.Concat() instead of string.Join().

plain count up timer in javascript

Timer for jQuery - smaller, working, tested.

_x000D_
_x000D_
    var sec = 0;_x000D_
    function pad ( val ) { return val > 9 ? val : "0" + val; }_x000D_
    setInterval( function(){_x000D_
        $("#seconds").html(pad(++sec%60));_x000D_
        $("#minutes").html(pad(parseInt(sec/60,10)));_x000D_
    }, 1000);
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<span id="minutes"></span>:<span id="seconds"></span>
_x000D_
_x000D_
_x000D_

Pure JavaScript:

_x000D_
_x000D_
    var sec = 0;_x000D_
    function pad ( val ) { return val > 9 ? val : "0" + val; }_x000D_
    setInterval( function(){_x000D_
        document.getElementById("seconds").innerHTML=pad(++sec%60);_x000D_
        document.getElementById("minutes").innerHTML=pad(parseInt(sec/60,10));_x000D_
    }, 1000);
_x000D_
<span id="minutes"></span>:<span id="seconds"></span>
_x000D_
_x000D_
_x000D_

Update:

This answer shows how to pad.

Stopping setInterval MDN is achieved with clearInterval MDN

var timer = setInterval ( function(){...}, 1000 );
...
clearInterval ( timer );

Fiddle

JPQL IN clause: Java-Arrays (or Lists, Sets...)?

I'm not sure for JPA 1.0 but you can pass a Collection in JPA 2.0:

String qlString = "select item from Item item where item.name IN :names"; 
Query q = em.createQuery(qlString, Item.class);

List<String> names = Arrays.asList("foo", "bar");

q.setParameter("names", names);
List<Item> actual = q.getResultList();

assertNotNull(actual);
assertEquals(2, actual.size());

Tested with EclipseLInk. With Hibernate 3.5.1, you'll need to surround the parameter with parenthesis:

String qlString = "select item from Item item where item.name IN (:names)";

But this is a bug, the JPQL query in the previous sample is valid JPQL. See HHH-5126.

Are multi-line strings allowed in JSON?

While not standard, I found that some of the JSON libraries have options to support multiline Strings. I am saying this with the caveat, that this will hurt your interoperability.

However in the specific scenario I ran into, I needed to make a config file that was only ever used by one system readable and manageable by humans. And opted for this solution in the end.

Here is how this works out on Java with Jackson:

JsonMapper mapper = JsonMapper.builder()
   .enable(JsonReadFeature.ALLOW_UNESCAPED_CONTROL_CHARS)
   .build()

Javascript: Setting location.href versus location

One difference to keep in mind, though.

Let's say you want to build some URL using the current URL. The following code will in fact redirect you, because it's not calling String.replace but Location.replace:

nextUrl = window.location.replace('/step1', '/step2');

The following codes work:

// cast to string
nextUrl = (window.location+'').replace('/step1', '/step2');

// href property
nextUrl = window.location.href.replace('/step1', '/step2');

could not extract ResultSet in hibernate

For MySql take in mind that it's not a good idea to write camelcase. For example if the schema is like that:

CREATE TABLE IF NOT EXISTS `task`(
    `id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY ,
    `teaching_hours` DECIMAL(5,2) DEFAULT NULL,
    `isActive` BOOLEAN DEFAULT FALSE,
    `is_validated` BOOLEAN DEFAULT FALSE,
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

You must be very careful cause isActive column will translate to isactive. So in your Entity class is should be like this:

 @Basic
 @Column(name = "isactive", nullable = true)
 public boolean isActive() {
     return isActive;
 }
 public void setActive(boolean active) {
     isActive = active;
 }

That was my problem at least that got me your error

This has nothing to do with MySql which is case insensitive, but rather is a naming strategy that spring will use to translate your tables. For more refer to this post

Should methods in a Java interface be declared with or without a public access modifier?

With the introduction of private, static, default modifiers for interface methods in Java 8/9, things get more complicated and I tend to think that full declarations are more readable (needs Java 9 to compile):

public interface MyInterface {

    //minimal
    int CONST00 = 0;
    void method00();
    static void method01() {}
    default void method02() {}
    private static void method03() {}
    private void method04() {}

    //full
    public static final int CONST10 = 0;
    public abstract void method10();
    public static void method11() {}
    public default void method12() {}
    private static void method13() {}
    private void method14() {}

}

Named placeholders in string formatting

not quite, but you can use MessageFormat to reference one value multiple times:

MessageFormat.format("There's an incorrect value \"{0}\" in column # {1}", x, y);

The above can be done with String.format() as well, but I find messageFormat syntax cleaner if you need to build complex expressions, plus you dont need to care about the type of the object you are putting into the string

Cannot issue data manipulation statements with executeQuery()

If you're using spring boot, just add an @Modifying annotation.

@Modifying
@Query
(value = "UPDATE user SET middleName = 'Mudd' WHERE id = 1", nativeQuery = true)
void updateMiddleName();

Remove all values within one list from another list?

I was looking for fast way to do the subject, so I made some experiments with suggested ways. And I was surprised by results, so I want to share it with you.

Experiments were done using pythonbenchmark tool and with

a = range(1,50000) # Source list
b = range(1,15000) # Items to remove

Results:

 def comprehension(a, b):
     return [x for x in a if x not in b]

5 tries, average time 12.8 sec

def filter_function(a, b):
    return filter(lambda x: x not in b, a)

5 tries, average time 12.6 sec

def modification(a,b):
    for x in b:
        try:
            a.remove(x)
        except ValueError:
            pass
    return a

5 tries, average time 0.27 sec

def set_approach(a,b):
    return list(set(a)-set(b))

5 tries, average time 0.0057 sec

Also I made another measurement with bigger inputs size for the last two functions

a = range(1,500000)
b = range(1,100000)

And the results:

For modification (remove method) - average time is 252 seconds For set approach - average time is 0.75 seconds

So you can see that approach with sets is significantly faster than others. Yes, it doesn't keep similar items, but if you don't need it - it's for you. And there is almost no difference between list comprehension and using filter function. Using 'remove' is ~50 times faster, but it modifies source list. And the best choice is using sets - it's more than 1000 times faster than list comprehension!

Total number of items defined in an enum

If you find yourself writing the above solution as often as I do then you could implement it as a generic:

public static int GetEnumEntries<T>() where T : struct, IConvertible 
{
    if (!typeof(T).IsEnum)
        throw new ArgumentException("T must be an enumerated type");

    return Enum.GetNames(typeof(T)).Length;
}

How to download a file via FTP with Python ftplib

handle = open(path.rstrip("/") + "/" + filename.lstrip("/"), 'wb')
ftp.retrbinary('RETR %s' % filename, handle.write)

Function ereg_replace() is deprecated - How to clear this bug?

http://php.net/ereg_replace says:

Note: As of PHP 5.3.0, the regex extension is deprecated in favor of the PCRE extension.

Thus, preg_replace is in every way better choice. Note there are some differences in pattern syntax though.

Creating an empty list in Python

I do not really know about it, but it seems to me, by experience, that jpcgt is actually right. Following example: If I use following code

t = [] # implicit instantiation
t = t.append(1)

in the interpreter, then calling t gives me just "t" without any list, and if I append something else, e.g.

t = t.append(2)

I get the error "'NoneType' object has no attribute 'append'". If, however, I create the list by

t = list() # explicit instantiation

then it works fine.

How to solve maven 2.6 resource plugin dependency?

Tried everything. I deleted m2e and installed m2e version 2.7.0. Then deleted the .m2 directory and force updated maven. It worked!

How should I throw a divide by zero exception in Java without actually dividing by zero?

public class ZeroDivisionException extends ArithmeticException {
    // ...
}

if (denominator == 0) {
    throw new ZeroDivisionException();
}

awk partly string match (if column/word partly matches)

Print lines where the third field is either snow or snowman only:

awk '$3~/^snow(man)?$/' file

Global and local variables in R

<- does assignment in the current environment.

When you're inside a function R creates a new environment for you. By default it includes everything from the environment in which it was created so you can use those variables as well but anything new you create will not get written to the global environment.

In most cases <<- will assign to variables already in the global environment or create a variable in the global environment even if you're inside a function. However, it isn't quite as straightforward as that. What it does is checks the parent environment for a variable with the name of interest. If it doesn't find it in your parent environment it goes to the parent of the parent environment (at the time the function was created) and looks there. It continues upward to the global environment and if it isn't found in the global environment it will assign the variable in the global environment.

This might illustrate what is going on.

bar <- "global"
foo <- function(){
    bar <- "in foo"
    baz <- function(){
        bar <- "in baz - before <<-"
        bar <<- "in baz - after <<-"
        print(bar)
    }
    print(bar)
    baz()
    print(bar)
}
> bar
[1] "global"
> foo()
[1] "in foo"
[1] "in baz - before <<-"
[1] "in baz - after <<-"
> bar
[1] "global"

The first time we print bar we haven't called foo yet so it should still be global - this makes sense. The second time we print it's inside of foo before calling baz so the value "in foo" makes sense. The following is where we see what <<- is actually doing. The next value printed is "in baz - before <<-" even though the print statement comes after the <<-. This is because <<- doesn't look in the current environment (unless you're in the global environment in which case <<- acts like <-). So inside of baz the value of bar stays as "in baz - before <<-". Once we call baz the copy of bar inside of foo gets changed to "in baz" but as we can see the global bar is unchanged. This is because the copy of bar that is defined inside of foo is in the parent environment when we created baz so this is the first copy of bar that <<- sees and thus the copy it assigns to. So <<- isn't just directly assigning to the global environment.

<<- is tricky and I wouldn't recommend using it if you can avoid it. If you really want to assign to the global environment you can use the assign function and tell it explicitly that you want to assign globally.

Now I change the <<- to an assign statement and we can see what effect that has:

bar <- "global"
foo <- function(){
    bar <- "in foo"   
    baz <- function(){
        assign("bar", "in baz", envir = .GlobalEnv)
    }
    print(bar)
    baz()
    print(bar)
}
bar
#[1] "global"
foo()
#[1] "in foo"
#[1] "in foo"
bar
#[1] "in baz"

So both times we print bar inside of foo the value is "in foo" even after calling baz. This is because assign never even considered the copy of bar inside of foo because we told it exactly where to look. However, this time the value of bar in the global environment was changed because we explicitly assigned there.

Now you also asked about creating local variables and you can do that fairly easily as well without creating a function... We just need to use the local function.

bar <- "global"
# local will create a new environment for us to play in
local({
    bar <- "local"
    print(bar)
})
#[1] "local"
bar
#[1] "global"

Disable Laravel's Eloquent timestamps

If you only need to only to disable updating updated_at just add this method to your model.

public function setUpdatedAtAttribute($value)
{
    // to Disable updated_at
}

This will override the parent setUpdatedAtAttribute() method. created_at will work as usual. Same way you can write a method to disable updating created_at only.

Calendar date to yyyy-MM-dd format in java

Your code is wrong. No point of parsing date and keep that as Date object.

You can format the calender date object when you want to display and keep that as a string.

Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE, 1);
Date date = cal.getTime();             
SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd");          
String inActiveDate = null;
try {
    inActiveDate = format1.format(date);
    System.out.println(inActiveDate );
} catch (ParseException e1) {
    // TODO Auto-generated catch block
    e1.printStackTrace();
}

Redis: How to access Redis log file

The log file will be where the configuration file (usually /etc/redis/redis.conf) says it is :)

By default, logfile stdout which probably isn't what you are looking for. If redis is running daemonized, then that log configuration means logs will be sent to /dev/null, i.e. discarded.

Summary: set logfile /path/to/my/log/file.log in your config and redis logs will be written to that file.

What's the right way to pass form element state to sibling/parent elements?

Five years later with introduction of React Hooks there is now much more elegant way of doing it with use useContext hook.

You define context in a global scope, export variables, objects and functions in the parent component and then wrap children in the App in a context provided and import whatever you need in child components. Below is a proof of concept.

import React, { useState, useContext } from "react";
import ReactDOM from "react-dom";
import styles from "./styles.css";

// Create context container in a global scope so it can be visible by every component
const ContextContainer = React.createContext(null);

const initialAppState = {
  selected: "Nothing"
};

function App() {
  // The app has a state variable and update handler
  const [appState, updateAppState] = useState(initialAppState);

  return (
    <div>
      <h1>Passing state between components</h1>

      {/* 
          This is a context provider. We wrap in it any children that might want to access
          App's variables.
          In 'value' you can pass as many objects, functions as you want. 
           We wanna share appState and its handler with child components,           
       */}
      <ContextContainer.Provider value={{ appState, updateAppState }}>
        {/* Here we load some child components */}
        <Book title="GoT" price="10" />
        <DebugNotice />
      </ContextContainer.Provider>
    </div>
  );
}

// Child component Book
function Book(props) {
  // Inside the child component you can import whatever the context provider allows.
  // Earlier we passed value={{ appState, updateAppState }}
  // In this child we need the appState and the update handler
  const { appState, updateAppState } = useContext(ContextContainer);

  function handleCommentChange(e) {
    //Here on button click we call updateAppState as we would normally do in the App
    // It adds/updates comment property with input value to the appState
    updateAppState({ ...appState, comment: e.target.value });
  }

  return (
    <div className="book">
      <h2>{props.title}</h2>
      <p>${props.price}</p>
      <input
        type="text"
        //Controlled Component. Value is reverse vound the value of the variable in state
        value={appState.comment}
        onChange={handleCommentChange}
      />
      <br />
      <button
        type="button"
        // Here on button click we call updateAppState as we would normally do in the app
        onClick={() => updateAppState({ ...appState, selected: props.title })}
      >
        Select This Book
      </button>
    </div>
  );
}

// Just another child component
function DebugNotice() {
  // Inside the child component you can import whatever the context provider allows.
  // Earlier we passed value={{ appState, updateAppState }}
  // but in this child we only need the appState to display its value
  const { appState } = useContext(ContextContainer);

  /* Here we pretty print the current state of the appState  */
  return (
    <div className="state">
      <h2>appState</h2>
      <pre>{JSON.stringify(appState, null, 2)}</pre>
    </div>
  );
}

const rootElement = document.body;
ReactDOM.render(<App />, rootElement);

You can run this example in the Code Sandbox editor.

Edit passing-state-with-context

Android: How to get a custom View's height and width?

Don't try to get them inside its constructor. Try Call them in onDraw() method.

NuGet Packages are missing

Comment the Compiler Option in WebConfig:

<!--<system.codedom>
<compilers>
  <compiler language="c#;cs;csharp" extension=".cs" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:6 /nowarn:1659;1699;1701" />
  <compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.VBCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:14 /nowarn:41008 /define:_MYTYPE=\&quot;Web\&quot; /optionInfer+" />
</compilers>
</system.codedom>-->

Update the Latest Version of Packages in Package Config File

  <package id="Microsoft.CodeDom.Providers.DotNetCompilerPlatform" version="1.0.4" targetFramework="net452" />

Rebuild if all ok, no need to proceed, else Right-click the project, click 'unload project' Right-click the project again and edit .csproj file

Validate the path of Codedom, it was not having net45 in previous paths, add that manually, save, load, rebuild. It should work.

<Import Project="..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.4\build\net45\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props" Condition="Exists('..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.4\build\net45\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props')" />

Jquery - How to make $.post() use contentType=application/json?

I ended up adding the following method to jQuery in my script:

jQuery["postJSON"] = function( url, data, callback ) {
    // shift arguments if data argument was omitted
    if ( jQuery.isFunction( data ) ) {
        callback = data;
        data = undefined;
    }

    return jQuery.ajax({
        url: url,
        type: "POST",
        contentType:"application/json; charset=utf-8",
        dataType: "json",
        data: data,
        success: callback
    });
};

And to use it

$.postJSON('http://url', {data: 'goes', here: 'yey'}, function (data, status, xhr) {
    alert('Nailed it!')
});

This was done by simply copying the code of "get" and "post" from the original JQuery sources and hardcoding a few parameters to force a JSON POST.

Thanks!

How can I remove a character from a string using JavaScript?

If you just want to remove single character and If you know index of a character you want to remove, you can use following function:

/**
 * Remove single character at particular index from string
 * @param {*} index index of character you want to remove
 * @param {*} str string from which character should be removed
 */
function removeCharAtIndex(index, str) {
    var maxIndex=index==0?0:index;
    return str.substring(0, maxIndex) + str.substring(index, str.length)
}

WPF Databinding: How do I access the "parent" data context?

You could try something like this:

...Binding="{Binding RelativeSource={RelativeSource FindAncestor, 
AncestorType={x:Type Window}}, Path=DataContext.AllowItemCommand}" ...

How to set proxy for wget?

Add below line(s) in file ~/.wgetrc or /etc/wgetrc (create the file if it is not there):

http_proxy = http://[Proxy_Server]:[port]
https_proxy = http://[Proxy_Server]:[port]
ftp_proxy = http://[Proxy_Server]:[port]

For more information, https://www.thegeekdiary.com/how-to-use-wget-to-download-file-via-proxy/

Count number of objects in list

Let's create an empty list (not required, but good to know):

> mylist <- vector(mode="list")

Let's put some stuff in it - 3 components/indexes/tags (whatever you want to call it) each with differing amounts of elements:

> mylist <- list(record1=c(1:10),record2=c(1:5),record3=c(1:2))

If you are interested in just the number of components in a list use:

> length(mylist)
[1] 3

If you are interested in the length of elements in a specific component of a list use: (both reference the same component here)

length(mylist[[1]])
[1] 10
length(mylist[["record1"]]
[1] 10

If you are interested in the length of all elements in all components of the list use:

> sum(sapply(mylist,length))
[1] 17

How to prevent scanf causing a buffer overflow in C?

If you are using gcc, you can use the GNU-extension a specifier to have scanf() allocate memory for you to hold the input:

int main()
{
  char *str = NULL;

  scanf ("%as", &str);
  if (str) {
      printf("\"%s\"\n", str);
      free(str);
  }
  return 0;
}

Edit: As Jonathan pointed out, you should consult the scanf man pages as the specifier might be different (%m) and you might need to enable certain defines when compiling.

How to avoid HTTP error 429 (Too Many Requests) python

if response.status_code == 429:
  time.sleep(int(response.headers["Retry-After"]))

Assigning default values to shell variables with a single command in bash

If the variable is same, then

: "${VARIABLE:=DEFAULT_VALUE}"

assigns DEFAULT_VALUE to VARIABLE if not defined. The double quotes prevent globbing and word splitting.

Also see Section 3.5.3, Shell Parameter Expansion, in the Bash manual.

How to detect idle time in JavaScript elegantly?

The problem with all these solutions, although correct, they are impractical, when taking into account the session timeout valuable set, using PHP, .NET or in the Application.cfc file for Coldfusion developers. The time set by the above solution needs to sync with the server side session timeout. If the two do not sync, you can run into problems that will just frustrate and confuse your users. For example, the server side session timeout might be set to 60 minutes, but the user may believe that he/she is safe, because the JavaScript idle time capture has increased the total amount of time a user can spend on a single page. The user may have spent time filling in a long form, and then goes to submit it. The session timeout might kick in before the form submission is processed. I tend to just give my users 180 minutes, and then use JavaScript to automatically log the user out. Essentially, using some of the code above, to create a simple timer, but without the capturing mouse event part. In this way my client side & server side time syncs perfectly. There is no confusion, if you show the time to the user in your UI, as it reduces. Each time a new page is accessed in the CMS, the server side session & JavaScript timer are reset. Simple & elegant. If a user stays on a single page for more than 180 minutes, I figure there is something wrong with the page, in the first place.

Change keystore password from no password to a non blank password

Add -storepass to keytool arguments.

keytool -storepasswd -storepass '' -keystore mykeystore.jks

But also notice that -list command does not always require a password. I could execute follow command in both cases: without password or with valid password

$JAVA_HOME/bin/keytool -list -keystore $JAVA_HOME/jre/lib/security/cacerts

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

Which is better, return value or out parameter?

return value is the normal value which is returned by your method.

Where as out parameter, well out and ref are 2 key words of C# they allow to pass variables as reference.

The big difference between ref and out is, ref should be initialised before and out don't

How can I let a user download multiple files when a button is clicked?

I've solved this a different way by using window.location. It works in Chrome, which fortunately is the only browser I had to support. Might be useful to someone. I'd initally used Dan's answer, which also needed the timeout I've used here or it only downloaded one file.

var linkArray = [];
linkArray.push("http://example.com/downloadablefile1");
linkArray.push("http://example.com/downloadablefile2");
linkArray.push("http://example.com/downloadablefile3");    

function (linkArray) {
  for (var i = 0; i < linkArray.length; i++) { 
    setTimeout(function (path) { window.location = path; }, 200 + i * 200, linkArray[i]);
  }        
};

How to Set OnClick attribute with value containing function in ie8?

You don't need to use setAttribute for that - This code works (IE8 also)

<div id="something" >Hello</div>
<script type="text/javascript" >
    (function() {
        document.getElementById("something").onclick = function() { 
            alert('hello'); 
        };
    })();
</script>

How to check if the docker engine and a docker container are running?

I ended up using

docker info

to check with a bash script if docker engine is running.

ajax jquery simple get request

i think the problem is that there is no data in the success-function because the request breaks up with an 401 error in your case and thus has no success.

if you use

$.ajax({
        url: "https://app.asana.com/-/api/0.1/workspaces/",
        type: 'GET',
         error: function (xhr, ajaxOptions, thrownError) {
    alert(xhr.status);
    alert(thrownError);
  }
    });

there will be your 401 code i think (this link says so)

Rails 4: List of available datatypes

You can access this list everytime you want (even if you don't have Internet access) through:

rails generate model -h

PowerShell The term is not recognized as cmdlet function script file or operable program

Yet another way this error message can occur...

If PowerShell is open in a directory other than the target file, e.g.:

If someScript.ps1 is located here: C:\SlowLearner\some_missing_path\someScript.ps1, then C:\SlowLearner>. ./someScript.ps1 wont work.

In that case, navigate to the path: cd some_missing_path then this would work:

C:\SlowLearner\some_missing_path>. ./someScript.ps1

Float to String format specifier

You can pass a format string to the ToString method, like so:

ToString("N4"); // 4 decimal points Number

If you want to see more modifiers, take a look at MSDN - Standard Numeric Format Strings

django order_by query set, ascending and descending

If for some reason you have null values you can use the F function like this:

from django.db.models import F

Reserved.objects.all().filter(client=client_id).order_by(F('check_in').desc(nulls_last=True))

So it will put last the null values. Documentation by Django: https://docs.djangoproject.com/en/stable/ref/models/expressions/#using-f-to-sort-null-values

How can I create an array with key value pairs?

My PHP is a little rusty, but I believe you're looking for indexed assignment. Simply use:

$catList[$row["datasource_id"]] = $row["title"];

In PHP arrays are actually maps, where the keys can be either integers or strings. Check out PHP: Arrays - Manual for more information.

Remove a prefix from a string

What about this (a bit late):

def remove_prefix(s, prefix):
    return s[len(prefix):] if s.startswith(prefix) else s

why are there two different kinds of for loops in java?

Something none of the other answers touch on is that your first loop is indexing though the list. Whereas the for-each loop is using an Iterator. Some lists like LinkedList will iterate faster with an Iterator versus get(i). This is because because link list's iterator keeps track of the current pointer. Whereas each get in your for i=0 to 9 has to recompute the offset into the linked list. In general, its better to use for-each or an Iterator because it will be using Collections iterator, which in theory is optimized for the collection type.

Reading specific XML elements from XML file

You could use an XPath, too. A bit old fashioned but still effective:

using System.Xml;

...

XmlDocument xmlDocument;

xmlDocument = new XmlDocument();
xmlDocument.LoadXml(xml);

foreach (XmlElement xmlElement in 
    xmlDocument.DocumentElement.SelectNodes("word[category='verb']"))
{
    Console.Out.WriteLine(xmlElement.OuterXml);
}

What does set -e mean in a bash script?

Script 1: without setting -e
#!/bin/bash
decho "hi"
echo "hello"
This will throw error in decho and program continuous to next line

Script 2: With setting -e
#!/bin/bash
set -e
decho "hi" 
echo "hello"
# Up to decho "hi" shell will process and program exit, it will not proceed further

Elegant way to create empty pandas DataFrame with NaN of type float

You could specify the dtype directly when constructing the DataFrame:

>>> df = pd.DataFrame(index=range(0,4),columns=['A'], dtype='float')
>>> df.dtypes
A    float64
dtype: object

Specifying the dtype forces Pandas to try creating the DataFrame with that type, rather than trying to infer it.

Could not load the Tomcat server configuration

You can install tomcat7 in ~/tomcat7 instead of /usr/share/tomcat7.

  1. Close Eclipse.
  2. Delete org.eclipse.wst.server.core.prefs and org.eclipse.jst.server.tomcat.core.prefs in {workspace-directory}/.metadata/.plugins/org.eclipse.core.runtime/.settings.
  3. Launch Eclipse.
  4. Go to Window->Show View->Other... and choose the Servers.
  5. Select Tomcat v7.0 Server from the server type and press Next.
  6. Enter /home/user/tomcat7 (not /usr/share/tomcat7) into the "Tomcat installation directory" and press Download.
  7. Wait a few minutes and press Finish.

tomcat7 worked correctly with Eclipse 4.4 on my Ubuntu 15.04 in this way.

Save each sheet in a workbook to separate CSV files

Here is one that will give you a visual file chooser to pick the folder you want to save the files to and also lets you choose the CSV delimiter (I use pipes '|' because my fields contain commas and I don't want to deal with quotes):

' ---------------------- Directory Choosing Helper Functions -----------------------
' Excel and VBA do not provide any convenient directory chooser or file chooser
' dialogs, but these functions will provide a reference to a system DLL
' with the necessary capabilities
Private Type BROWSEINFO    ' used by the function GetFolderName
    hOwner As Long
    pidlRoot As Long
    pszDisplayName As String
    lpszTitle As String
    ulFlags As Long
    lpfn As Long
    lParam As Long
    iImage As Long
End Type

Private Declare Function SHGetPathFromIDList Lib "shell32.dll" _
                                             Alias "SHGetPathFromIDListA" (ByVal pidl As Long, ByVal pszPath As String) As Long
Private Declare Function SHBrowseForFolder Lib "shell32.dll" _
                                           Alias "SHBrowseForFolderA" (lpBrowseInfo As BROWSEINFO) As Long

Function GetFolderName(Msg As String) As String
    ' returns the name of the folder selected by the user
    Dim bInfo As BROWSEINFO, path As String, r As Long
    Dim X As Long, pos As Integer
    bInfo.pidlRoot = 0&    ' Root folder = Desktop
    If IsMissing(Msg) Then
        bInfo.lpszTitle = "Select a folder."
        ' the dialog title
    Else
        bInfo.lpszTitle = Msg    ' the dialog title
    End If
    bInfo.ulFlags = &H1    ' Type of directory to return
    X = SHBrowseForFolder(bInfo)    ' display the dialog
    ' Parse the result
    path = Space$(512)
    r = SHGetPathFromIDList(ByVal X, ByVal path)
    If r Then
        pos = InStr(path, Chr$(0))
        GetFolderName = Left(path, pos - 1)
    Else
        GetFolderName = ""
    End If
End Function
'---------------------- END Directory Chooser Helper Functions ----------------------

Public Sub DoTheExport()
    Dim FName As Variant
    Dim Sep As String
    Dim wsSheet As Worksheet
    Dim nFileNum As Integer
    Dim csvPath As String


    Sep = InputBox("Enter a single delimiter character (e.g., comma or semi-colon)", _
                   "Export To Text File")
    'csvPath = InputBox("Enter the full path to export CSV files to: ")

    csvPath = GetFolderName("Choose the folder to export CSV files to:")
    If csvPath = "" Then
        MsgBox ("You didn't choose an export directory. Nothing will be exported.")
        Exit Sub
    End If

    For Each wsSheet In Worksheets
        wsSheet.Activate
        nFileNum = FreeFile
        Open csvPath & "\" & _
             wsSheet.Name & ".csv" For Output As #nFileNum
        ExportToTextFile CStr(nFileNum), Sep, False
        Close nFileNum
    Next wsSheet

End Sub



Public Sub ExportToTextFile(nFileNum As Integer, _
                            Sep As String, SelectionOnly As Boolean)

    Dim WholeLine As String
    Dim RowNdx As Long
    Dim ColNdx As Integer
    Dim StartRow As Long
    Dim EndRow As Long
    Dim StartCol As Integer
    Dim EndCol As Integer
    Dim CellValue As String

    Application.ScreenUpdating = False
    On Error GoTo EndMacro:

    If SelectionOnly = True Then
        With Selection
            StartRow = .Cells(1).Row
            StartCol = .Cells(1).Column
            EndRow = .Cells(.Cells.Count).Row
            EndCol = .Cells(.Cells.Count).Column
        End With
    Else
        With ActiveSheet.UsedRange
            StartRow = .Cells(1).Row
            StartCol = .Cells(1).Column
            EndRow = .Cells(.Cells.Count).Row
            EndCol = .Cells(.Cells.Count).Column
        End With
    End If

    For RowNdx = StartRow To EndRow
        WholeLine = ""
        For ColNdx = StartCol To EndCol
            If Cells(RowNdx, ColNdx).Value = "" Then
                CellValue = ""
            Else
                CellValue = Cells(RowNdx, ColNdx).Value
            End If
            WholeLine = WholeLine & CellValue & Sep
        Next ColNdx
        WholeLine = Left(WholeLine, Len(WholeLine) - Len(Sep))
        Print #nFileNum, WholeLine
    Next RowNdx

EndMacro:
    On Error GoTo 0
    Application.ScreenUpdating = True

End Sub

Getting a browser's name client-side

JavaScript side - you can get browser name like these ways...

if(window.navigator.appName == "") OR if(window.navigator.userAgent == "")

How to make Bitmap compress without change the bitmap size?

Are you sure it is smaller?

Bitmap original = BitmapFactory.decodeStream(getAssets().open("1024x768.jpg"));
ByteArrayOutputStream out = new ByteArrayOutputStream();
original.compress(Bitmap.CompressFormat.PNG, 100, out);
Bitmap decoded = BitmapFactory.decodeStream(new ByteArrayInputStream(out.toByteArray()));

Log.e("Original   dimensions", original.getWidth()+" "+original.getHeight());
Log.e("Compressed dimensions", decoded.getWidth()+" "+decoded.getHeight());

Gives

12-07 17:43:36.333: E/Original   dimensions(278): 1024 768
12-07 17:43:36.333: E/Compressed dimensions(278): 1024 768

Maybe you get your bitmap from a resource, in which case the bitmap dimension will depend on the phone screen density

Bitmap bitmap=((BitmapDrawable)getResources().getDrawable(R.drawable.img_1024x768)).getBitmap();
Log.e("Dimensions", bitmap.getWidth()+" "+bitmap.getHeight());

12-07 17:43:38.733: E/Dimensions(278): 768 576

Java : Cannot format given Object as a Date

You have one DateFormat, but you need two: one for the input, and another for the output.

You've got one for the output, but I don't see anything that would match your input. When you give the input string to the output format, it's no surprise that you see that exception.

DateFormat inputDateFormat = new SimpleDateFormat("yyyy-MM-ddhh:mm:ss.SSS-Z");

AJAX jQuery refresh div every 5 seconds

Try this out.

function loadlink(){
    $('#links').load('test.php',function () {
         $(this).unwrap();
    });
}

loadlink(); // This will run on page load
setInterval(function(){
    loadlink() // this will run after every 5 seconds
}, 5000);

Hope this helps.

Cannot stop or restart a docker container

All the docker: start | restart | stop | rm --force | kill commands may not work if the container is stuck. You can always restart the docker daemon. However, if you have other containers running, that may not be the option. What you can do is:

ps aux | grep <<container id>> | awk '{print $1 $2}'

The output contains:

<<user>><<process id>>

Then kill the process associated with the container like so:

sudo kill -9 <<process id from above command>>

That will kill the container and you can start a new container with the right image.

Saving to CSV in Excel loses regional date format

A not so scalable fix that I used for this is to copy the data to a plain text editor, convert the cells to text and then copy the data back to the spreadsheet.

How to remove text from a string?

This little function I made has always worked for me :)

String.prototype.deleteWord = function (searchTerm) {
    var str = this;
    var n = str.search(searchTerm);
    while (str.search(searchTerm) > -1) {
        n = str.search(searchTerm);
        str = str.substring(0, n) + str.substring(n + searchTerm.length, str.length);
    }
    return str;
}

// Use it like this:
var string = "text is the cool!!";
string.deleteWord('the'); // Returns text is cool!!

I know it is not the best, but It has always worked for me :)

How to Convert JSON object to Custom C# object?

JSON.Net is your best bet but, depending on the shape of the objects and whether there are circular dependencies, you could use JavaScriptSerializer or DataContractSerializer.

How to connect TFS in Visual Studio code

Just as Daniel said "Git and TFVC are the two source control options in TFS". Fortunately both are supported for now in VS Code.

You need to install the Azure Repos Extension for Visual Studio Code. The process of installing is pretty straight forward.

  1. Search for Azure Repos in VS Code and select to install the one by Microsoft
  2. Open File -> Preferences -> Settings
  3. Add the following lines to your user settings

    If you have VS 2015 installed on your machine, your path to Team Foundation tool (tf.exe) may look like this:

    {
        "tfvc.location": "C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\Common7\\IDE\\tf.exe",
        "tfvc.restrictWorkspace": true
    }

    Or for VS 2017:

    {
        "tfvc.location": "C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Enterprise\\Common7\\IDE\\CommonExtensions\\Microsoft\\TeamFoundation\\Team Explorer\\tf.exe",
        "tfvc.restrictWorkspace": true
    }
  4. Open a local folder (repository), From View -> Command Pallette ..., type team signin

  5. Provide user name --> Enter --> Provide password to connect to TFS.

Please refer to below links for more details:

Note that Server Workspaces are not supported:

"TFVC support is limited to Local workspaces":

on installing Azure extension, visual studio code warns you "It appears you are using a Server workspace. Currently, TFVC support is limited to Local workspaces"

Selenium Finding elements by class name in python

As per the HTML:

<html>
    <body>
    <p class="content">Link1.</p>
    </body>
<html>
<html>
    <body>
    <p class="content">Link2.</p>
    </body>
<html>

Two(2) <p> elements are having the same class content.

So to filter the elements having the same class i.e. content and create a list you can use either of the following Locator Strategies:

  • Using class_name:

    elements = driver.find_elements_by_class_name("content")
    
  • Using css_selector:

     elements = driver.find_elements_by_css_selector(".content")
    
  • Using xpath:

    elements = driver.find_elements_by_xpath("//*[@class='content']")
    

Ideally, to click on the element you need to induce WebDriverWait for the visibility_of_all_elements_located() and you can use either of the following Locator Strategies:

  • Using CLASS_NAME:

    elements = WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.CLASS_NAME, "content")))
    
  • Using CSS_SELECTOR:

    elements = WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.CSS_SELECTOR, ".content")))
    
  • Using XPATH:

    elements = WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.XPATH, "//*[@class='content']")))
    
  • Note : You have to add the following imports :

    from selenium.webdriver.support.ui import WebDriverWait
    from selenium.webdriver.common.by import By
    from selenium.webdriver.support import expected_conditions as EC
    

References

You can find a couple of relevant discussions in:

How can I get the iOS 7 default blue color programmatically?

Adding a category to UIColor the following way will make it available to you anytime you need it or even change its definition accross your code:

@interface UIColor (iOS7Colors)

+ (instancetype)iOS7blueColor;

@end

@implementation UIColor (SpecialColors)

+ (instancetype)iOS7blueColor;
{
    return [UIColor colorWithRed:0.0f green:0.22f blue:122.0/255.0 alpha:1.0f];
}

Once you import the Category in your code you can call the color by using:

UIColor *myBlueColor = [UIColor iOSblueColor];

the MySQL service on local computer started and then stopped

Delete or rename the 2 following files from "C:\ProgramData\MySQL\MySQL Server 5.7\Data": ib_logfile0 ib_logfile1

Adding values to specific DataTable cells

Try this:

dt.Rows[RowNumber]["ColumnName"] = "Your value"

For example: if you want to add value 5 (number 5) to 1st row and column name "index" you would do this

dt.Rows[0]["index"] = 5;

I believe DataTable row starts with 0

Custom Python list sorting

Even better:

student_tuples = [
    ('john', 'A', 15),
    ('jane', 'B', 12),
    ('dave', 'B', 10),
]

sorted(student_tuples, key=lambda student: student[2])   # sort by age
[('dave', 'B', 10), ('jane', 'B', 12), ('john', 'A', 15)]

Taken from: https://docs.python.org/3/howto/sorting.html

Programmatically change the src of an img tag

In this case, as you want to change the src of the first value of your element, you have no need to build up a function. You can change this right in the element:

<a href='#' onclick='this.firstChild.src="../template/save.png"')'>
  <img src="../template/edit.png" id="edit-save"/>
</a>

You have several ways to do this. You can also create a function to automatize the process:

function changeSrc(p, t) { /* where p: Parent, t: ToSource */
  p.firstChild.src = t
}

Then you can:

<a href='#' onclick='changeSrc(this, "../template/save.png");'>
  <img src="../template/edit.png" id="edit-save"/>
</a>

What is the maximum possible length of a .NET string?

The max length of a string on my machine is 1,073,741,791.

You see, Strings aren't limited by integer as is commonly believed.

Memory restrictions aside, Strings cannot have more than 230 (1,073,741,824) characters, since a 2GB limit is imposed by the Microsoft CLR (Common Language Runtime). 33 more than my computer allowed.

Now, here's something you're welcome to try yourself.

Create a new C# console app in Visual Studio and then copy/paste the main method here:

static void Main(string[] args)
{
    Console.WriteLine("String test, by Nicholas John Joseph Taylor");

    Console.WriteLine("\nTheoretically, C# should support a string of int.MaxValue, but we run out of memory before then.");

    Console.WriteLine("\nThis is a quickish test to narrow down results to find the max supported length of a string.");

    Console.WriteLine("\nThe test starts ...now:\n");

    int Length = 0;

    string s = "";

    int Increment = 1000000000; // We know that s string with the length of 1000000000 causes an out of memory exception.

    LoopPoint:

    // Make a string appendage the length of the value of Increment

    StringBuilder StringAppendage = new StringBuilder();

    for (int CharacterPosition = 0; CharacterPosition < Increment; CharacterPosition++)
    {
        StringAppendage.Append("0");

    }

    // Repeatedly append string appendage until an out of memory exception is thrown.

    try
    {
        if (Increment > 0)
            while (Length < int.MaxValue)
            {
                Length += Increment;

                s += StringAppendage.ToString(); // Append string appendage the length of the value of Increment

                Console.WriteLine("s.Length = " + s.Length + " at " + DateTime.Now.ToString("dd/MM/yyyy HH:mm"));

            }

    }
    catch (OutOfMemoryException ex) // Note: Any other exception will crash the program.
    {
        Console.WriteLine("\n" + ex.Message + " at " + DateTime.Now.ToString("dd/MM/yyyy HH:mm") + ".");

        Length -= Increment;

        Increment /= 10;

        Console.WriteLine("After decimation, the value of Increment is " + Increment + ".");

    }
    catch (Exception ex2)
    {
        Console.WriteLine("\n" + ex2.Message + " at " + DateTime.Now.ToString("dd/MM/yyyy HH:mm") + ".");

        Console.WriteLine("Press a key to continue...");

        Console.ReadKey();

    }

    if (Increment > 0)
    {
        goto LoopPoint;

    }

    Console.WriteLine("Test complete.");

    Console.WriteLine("\nThe max length of a string is " + s.Length + ".");

    Console.WriteLine("\nPress any key to continue.");

    Console.ReadKey();

}

My results were as follows:

String test, by Nicholas John Joseph Taylor

Theoretically, C# should support a string of int.MaxValue, but we run out of memory before then.

This is a quickish test to narrow down results to find the max supported length of a string.

The test starts ...now:

s.Length = 1000000000 at 08/05/2019 12:06

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:06. After decimation, the value of Increment is 100000000.

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:06. After decimation, the value of Increment is 10000000. s.Length = 1010000000 at 08/05/2019 12:06 s.Length = 1020000000 at 08/05/2019 12:06 s.Length = 1030000000 at 08/05/2019 12:06 s.Length = 1040000000 at 08/05/2019 12:06 s.Length = 1050000000 at 08/05/2019 12:06 s.Length = 1060000000 at 08/05/2019 12:06 s.Length = 1070000000 at 08/05/2019 12:06

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:06. After decimation, the value of Increment is 1000000. s.Length = 1071000000 at 08/05/2019 12:06 s.Length = 1072000000 at 08/05/2019 12:06 s.Length = 1073000000 at 08/05/2019 12:06

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:06. After decimation, the value of Increment is 100000. s.Length = 1073100000 at 08/05/2019 12:06 s.Length = 1073200000 at 08/05/2019 12:06 s.Length = 1073300000 at 08/05/2019 12:06 s.Length = 1073400000 at 08/05/2019 12:06 s.Length = 1073500000 at 08/05/2019 12:06 s.Length = 1073600000 at 08/05/2019 12:06 s.Length = 1073700000 at 08/05/2019 12:06

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:06. After decimation, the value of Increment is 10000. s.Length = 1073710000 at 08/05/2019 12:06 s.Length = 1073720000 at 08/05/2019 12:06 s.Length = 1073730000 at 08/05/2019 12:06 s.Length = 1073740000 at 08/05/2019 12:06

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:06. After decimation, the value of Increment is 1000. s.Length = 1073741000 at 08/05/2019 12:06

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:06. After decimation, the value of Increment is 100. s.Length = 1073741100 at 08/05/2019 12:06 s.Length = 1073741200 at 08/05/2019 12:06 s.Length = 1073741300 at 08/05/2019 12:07 s.Length = 1073741400 at 08/05/2019 12:07 s.Length = 1073741500 at 08/05/2019 12:07 s.Length = 1073741600 at 08/05/2019 12:07 s.Length = 1073741700 at 08/05/2019 12:07

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:07. After decimation, the value of Increment is 10. s.Length = 1073741710 at 08/05/2019 12:07 s.Length = 1073741720 at 08/05/2019 12:07 s.Length = 1073741730 at 08/05/2019 12:07 s.Length = 1073741740 at 08/05/2019 12:07 s.Length = 1073741750 at 08/05/2019 12:07 s.Length = 1073741760 at 08/05/2019 12:07 s.Length = 1073741770 at 08/05/2019 12:07 s.Length = 1073741780 at 08/05/2019 12:07 s.Length = 1073741790 at 08/05/2019 12:07

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:07. After decimation, the value of Increment is 1. s.Length = 1073741791 at 08/05/2019 12:07

Exception of type 'System.OutOfMemoryException' was thrown. at 08/05/2019 12:07. After decimation, the value of Increment is 0. Test complete.

The max length of a string is 1073741791.

Press any key to continue.

The max length of a string on my machine is 1073741791.

I'd appreciate it very much if people could post their results as a comment below.

It will be interesting to learn if people get the same or different results.

How can I remove all my changes in my SVN working directory?

svn revert will undo any local changes you've made

Select something that has more/less than x character

Today I was trying same in db2 and used below, in my case I had spaces at the end of varchar column data

SELECT EmployeeName FROM EmployeeTable WHERE LENGTH(TRIM(EmployeeName))> 4;

How to do scanf for single char in C

You have to use a valid variable. ch is not a valid variable for this program. Use char Aaa;

char aaa;
scanf("%c",&Aaa);

Tested and it works.

jQuery xml error ' No 'Access-Control-Allow-Origin' header is present on the requested resource.'

You won't be able to make an ajax call to http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml from a file deployed at http://run.jsbin.com due to the same-origin policy.


As the source (aka origin) page and the target URL are at different domains (run.jsbin.com and www.ecb.europa.eu), your code is actually attempting to make a Cross-domain (CORS) request, not an ordinary GET.

In a few words, the same-origin policy says that browsers should only allow ajax calls to services at the same domain of the HTML page.


Example:

A page at http://www.example.com/myPage.html can only directly request services that are at http://www.example.com, like http://www.example.com/api/myService. If the service is hosted at another domain (say http://www.ok.com/api/myService), the browser won't make the call directly (as you'd expect). Instead, it will try to make a CORS request.

To put it shortly, to perform a (CORS) request* across different domains, your browser:

  • Will include an Origin header in the original request (with the page's domain as value) and perform it as usual; and then
  • Only if the server response to that request contains the adequate headers (Access-Control-Allow-Origin is one of them) allowing the CORS request, the browse will complete the call (almost** exactly the way it would if the HTML page was at the same domain).
    • If the expected headers don't come, the browser simply gives up (like it did to you).


* The above depicts the steps in a simple request, such as a regular GET with no fancy headers. If the request is not simple (like a POST with application/json as content type), the browser will hold it a moment, and, before fulfilling it, will first send an OPTIONS request to the target URL. Like above, it only will continue if the response to this OPTIONS request contains the CORS headers. This OPTIONS call is known as preflight request.
** I'm saying almost because there are other differences between regular calls and CORS calls. An important one is that some headers, even if present in the response, will not be picked up by the browser if they aren't included in the Access-Control-Expose-Headers header.


How to fix it?

Was it just a typo? Sometimes the JavaScript code has just a typo in the target domain. Have you checked? If the page is at www.example.com it will only make regular calls to www.example.com! Other URLs, such as api.example.com or even example.com or www.example.com:8080 are considered different domains by the browser! Yes, if the port is different, then it is a different domain!

Add the headers. The simplest way to enable CORS is by adding the necessary headers (as Access-Control-Allow-Origin) to the server's responses. (Each server/language has a way to do that - check some solutions here.)

Last resort: If you don't have server-side access to the service, you can also mirror it (through tools such as reverse proxies), and include all the necessary headers there.

Choose folders to be ignored during search in VS Code

Exclude all from subfolders works like this (version 2019)

include

./db

exclude

./db/*

Make a div fill up the remaining width

I was looking for a solution to the opposite problem where I needed a fixed width div in the centre and a fluid width div on either side, so I came up with the following and thought I'd post it here in case anyone needs it.

_x000D_
_x000D_
#wrapper {_x000D_
  clear: both;_x000D_
  width: 100%;_x000D_
}_x000D_
_x000D_
#wrapper div {_x000D_
  display: inline-block;_x000D_
  height: 500px;_x000D_
}_x000D_
_x000D_
#center {_x000D_
  background-color: green;_x000D_
  margin: 0 auto;_x000D_
  overflow: auto;_x000D_
  width: 500px;_x000D_
}_x000D_
_x000D_
#left {_x000D_
  float: left;_x000D_
}_x000D_
_x000D_
#right {_x000D_
  float: right;_x000D_
}_x000D_
_x000D_
.fluid {_x000D_
  background-color: yellow;_x000D_
  width: calc(50% - 250px);_x000D_
}
_x000D_
<div id="wrapper">_x000D_
  <div id="center">_x000D_
    This is fixed width in the centre_x000D_
  </div>_x000D_
  <div id="left" class="fluid">_x000D_
    This is fluid width on the left_x000D_
  </div>_x000D_
  <div id="right" class="fluid">_x000D_
    This is fluid width on the right_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

If you change the width of the #center element then you need to update the width property of .fluid to:

width: calc(50% - [half of center width]px);

How to get a path to the desktop for current user in C#?

 string filePath = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
 string extension = ".log";
 filePath += @"\Error Log\" + extension;
 if (!Directory.Exists(filePath))
 {
      Directory.CreateDirectory(filePath);
 }

Unable to set data attribute using jQuery Data() API

I was having serious problems with

.data('property', value);

It was not setting the data-property attribute.

Started using jQuery's .attr():

Get the value of an attribute for the first element in the set of matched elements or set one or more attributes for every matched element.

.attr('property', value)

to set the value and

.attr('property')

to retrieve the value.

Now it just works!

Why is synchronized block better than synchronized method?

synchronized should only be used when you want your class to be Thread safe. In fact most of the classes should not use synchronized anyways. synchronized method would only provide a lock on this object and only for the duration of its execution. if you really wanna to make your classes thread safe, you should consider making your variables volatile or synchronize the access.

one of the issues of using synchronized method is that all of the members of the class would use the same lock which will make your program slower. In your case synchronized method and block would execute no different. what I'd would recommend is to use a dedicated lock and use a synchronized block something like this.

public class AClass {
private int x;
private final Object lock = new Object();     //it must be final!

 public void setX() {
    synchronized(lock) {
        x++;
    }
 }
}

ArrayBuffer to base64 encoded string

function _arrayBufferToBase64( buffer ) {
    var binary = '';
    var bytes = new Uint8Array( buffer );
    var len = bytes.byteLength;
    for (var i = 0; i < len; i++) {
        binary += String.fromCharCode( bytes[ i ] );
    }
    return window.btoa( binary );
}

but, non-native implementations are faster e.g. https://gist.github.com/958841 see http://jsperf.com/encoding-xhr-image-data/6

jQuery: how to get which button was clicked upon form submission?

Similar to Stan answer but :

  • if you have more than one button, you have to get only the first button => [0]
  • if the form can be submitted with the enter key, you have to manage a default => myDefaultButtonId

$(document).on('submit', function(event) {
    event.preventDefault();
    var pressedButtonId = 
         typeof $(":input[type=submit]:focus")[0] === "undefined" ? 
         "myDefaultButtonId" :
         $(":input[type=submit]:focus")[0].id;
    ...
 }

What's the PowerShell syntax for multiple values in a switch statement?

After searching a solution for the same problem like you, I've found this small topic here. In advance I got a much smoother solution for this switch, case statement

switch($someString) #switch is caseINsensitive, so you don't need to lower
{
    { 'y' -or 'yes' } { "You entered Yes." }
    default { "You entered No." }
}

Why is "cursor:pointer" effect in CSS not working

The problem in my case was that the :after blocked mouse events, so I had to add pointer-events: none; to my :after block.

CSS Inset Borders

To produce a border inset within an element the only solution I've found (and I've tried all the suggestions in this thread to no avail) is to use a pseudo-element such as :before

E.g.

.has-inset-border:before {
  content: "foo"; /* you need something or it will be invisible at least on Chrome */
  color: transparent;
  position: absolute;
  left: 10px;
  right: 10px;
  top: 10px;
  bottom: 10px;
  border: 4px dashed red;
}

The box-sizing property won't work, as the border always ends up outside everything.

The box-shadow options has the dual disadvantages of not really working and not being supported as widely (and costing more CPU cycles to render, if you care).

Getting data from selected datagridview row and which event?

You can use SelectionChanged event since you are using FullRowSelect selection mode. Than inside the handler you can access SelectedRows property and get data from it. Example:

private void dataGridView_SelectionChanged(object sender, EventArgs e) 
{
    foreach (DataGridViewRow row in dataGridView.SelectedRows) 
    {
        string value1 = row.Cells[0].Value.ToString();
        string value2 = row.Cells[1].Value.ToString();
        //...
    }
}

You can also walk through the column collection instead of typing indexes...

SQL: Combine Select count(*) from multiple tables

I'm surprised no one has suggested this variation:

SELECT SUM(c)
FROM (
  SELECT COUNT(*) AS c FROM foo1 WHERE ID = '00123244552000258'
  UNION ALL
  SELECT COUNT(*) FROM foo2 WHERE ID = '00123244552000258'
  UNION ALL
  SELECT COUNT(*) FROM foo3 WHERE ID = '00123244552000258'
);

Inserting created_at data with Laravel

$data = array();
$data['created_at'] =new \DateTime();
DB::table('practice')->insert($data);

How do I insert multiple checkbox values into a table?

I think you should $_POST[][], i tried it and it work :)), tks

MySQL check if a table exists without throwing an exception

I don't know the PDO syntax for it, but this seems pretty straight-forward:

$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;

Difference between signature versions - V1 (Jar Signature) and V2 (Full APK Signature) while generating a signed APK in Android Studio?

It is a new signing mechanism introduced in Android 7.0, with additional features designed to make the APK signature more secure.

It is not mandatory. You should check BOTH of those checkboxes if possible, but if the new V2 signing mechanism gives you problems, you can omit it.

So you can just leave V2 unchecked if you encounter problems, but should have it checked if possible.

UPDATED: This is now mandatory when targeting Android 11.

What is logits, softmax and softmax_cross_entropy_with_logits?

Above answers have enough description for the asked question.

Adding to that, Tensorflow has optimised the operation of applying the activation function then calculating cost using its own activation followed by cost functions. Hence it is a good practice to use: tf.nn.softmax_cross_entropy() over tf.nn.softmax(); tf.nn.cross_entropy()

You can find prominent difference between them in a resource intensive model.

<select> HTML element with height

I've used a few CSS hacks and targeted Chrome/Safari/Firefox/IE individually, as each browser renders selects a bit differently. I've tested on all browsers except IE.

For Safari/Chrome, set the height and line-height you want for your <select />.

For Firefox, we're going to kill Firefox's default padding and border, then set our own. Set padding to whatever you like.

For IE 8+, just like Chrome, we've set the height and line-height properties. These two media queries can be combined. But I kept it separate for demo purposes. So you can see what I'm doing.

Please note, for the height/line-height property to work in Chrome/Safari OSX, you must set the background to a custom value. I changed the color in my example.

Here's a jsFiddle of the below: http://jsfiddle.net/URgCB/4/

For the non-hack route, why not use a custom select plug-in via jQuery? Check out this: http://codepen.io/wallaceerick/pen/ctsCz

HTML:

<select>
    <option>Here's one option</option>
    <option>here's another option</option>
</select>

CSS:

@media screen and (-webkit-min-device-pixel-ratio:0) {  /*safari and chrome*/
    select {
        height:30px;
        line-height:30px;
        background:#f4f4f4;
    } 
}
select::-moz-focus-inner { /*Remove button padding in FF*/ 
    border: 0;
    padding: 0;
}
@-moz-document url-prefix() { /* targets Firefox only */
    select {
        padding: 15px 0!important;
    }
}        
@media screen\0 { /* IE Hacks: targets IE 8, 9 and 10 */        
    select {
        height:30px;
        line-height:30px;
    }     
}

CSS selector for text input fields?

You can use :text Selector to select all inputs with type text

Working Fiddle

$(document).ready(function () {
    $(":text").css({    //or $("input:text")
        'background': 'green',
        'color':'#fff'
    });
});

:text is a jQuery extension and not part of the CSS specification, queries using :text cannot take advantage of the performance boost provided by the native DOM querySelectorAll() method. For better performance in modern browsers, use [type="text"] instead. This will work for IE6+.

$("[type=text]").css({  // or $("input[type=text]")
    'background': 'green',
    'color':'#fff'
});

CSS

[type=text] // or input[type=text] 
{
    background: green;
}

How can I save application settings in a Windows Forms application?

Other options, instead of using a custom XML file, we can use a more user friendly file format: JSON or YAML file.

  • If you use .NET 4.0 dynamic, this library is really easy to use (serialize, deserialize, nested objects support and ordering output as you wish + merging multiple settings to one) JsonConfig (usage is equivalent to ApplicationSettingsBase)
  • For .NET YAML configuration library... I haven't found one that is as easy to use as JsonConfig

You can store your settings file in multiple special folders (for all users and per user) as listed here Environment.SpecialFolder Enumeration and multiple files (default read only, per role, per user, etc.)

If you choose to use multiple settings, you can merge those settings: For example, merging settings for default + BasicUser + AdminUser. You can use your own rules: the last one overrides the value, etc.

how to create Socket connection in Android?

Simple socket server app example

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

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

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

To play with it:

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

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

package com.cirosantilli.android_cheat.socket;

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

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

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

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

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

AndroidManifest.xml

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

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

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

How to: Create trigger for auto update modified date with SQL Server 2008

My approach:

  • define a default constraint on the ModDate column with a value of GETDATE() - this handles the INSERT case

  • have a AFTER UPDATE trigger to update the ModDate column

Something like:

CREATE TRIGGER trg_UpdateTimeEntry
ON dbo.TimeEntry
AFTER UPDATE
AS
    UPDATE dbo.TimeEntry
    SET ModDate = GETDATE()
    WHERE ID IN (SELECT DISTINCT ID FROM Inserted)

How to clone git repository with specific revision/changeset?

I use this snippet with GNU make to close any revision tag, branch or hash

it was tested on git version 2.17.1

${dir}:
    mkdir -p ${@D}
    git clone --recursive --depth 1 --branch ${revison} ${url} ${@} \
 || git clone --recursive --branch ${revison} ${url} ${@} \
 || git clone ${url} ${@}
    cd ${@} && git reset --hard ${revison}
    ls $@




How to programmatically set SelectedValue of Dropdownlist when it is bound to XmlDataSource

Have you tried, after calling DataBind on your DropDownList, to do something like ddl.SelectedIndex = 0 ?

Getting a union of two arrays in JavaScript

I like Peter Ajtai's concat-then-unique solution, but the code's not very clear. Here's a nicer alternative:

function unique(x) {
  return x.filter(function(elem, index) { return x.indexOf(elem) === index; });
};
function union(x, y) {
  return unique(x.concat(y));
};

Since indexOf returns the index of the first occurence, we check this against the current element's index (the second parameter to the filter predicate).

Convert a String representation of a Dictionary to a dictionary?

Use json. the ast library consumes a lot of memory and and slower. I have a process that needs to read a text file of 156Mb. Ast with 5 minutes delay for the conversion dictionary json and 1 minutes using 60% less memory!

git still shows files as modified after adding to .gitignore

Simply add git rm -r --cached <folder_name/file_name>

Sometimes, you update the .gitignore file after the commit command of files. So, the files get cached in the memory. To remove the cached files, use the above command.

Equivalent VB keyword for 'break'

In case you're inside a Sub of Function and you want to exit it, you can use :

Exit Sub

or

Exit Function 

How print out the contents of a HashMap<String, String> in ascending order based on its values?

while (itr.hasNext()) {
    Vehicle vc=(Vehicle) itr.next();
    if(vc.getVehicleType().equalsIgnoreCase(s)) {
        count++;
    }
}

BasicHttpBinding vs WsHttpBinding vs WebHttpBinding

You're comparing apples to oranges here:

  • webHttpBinding is the REST-style binding, where you basically just hit a URL and get back a truckload of XML or JSON from the web service

  • basicHttpBinding and wsHttpBinding are two SOAP-based bindings which is quite different from REST. SOAP has the advantage of having WSDL and XSD to describe the service, its methods, and the data being passed around in great detail (REST doesn't have anything like that - yet). On the other hand, you can't just browse to a wsHttpBinding endpoint with your browser and look at XML - you have to use a SOAP client, e.g. the WcfTestClient or your own app.

So your first decision must be: REST vs. SOAP (or you can expose both types of endpoints from your service - that's possible, too).

Then, between basicHttpBinding and wsHttpBinding, there differences are as follows:

  • basicHttpBinding is the very basic binding - SOAP 1.1, not much in terms of security, not much else in terms of features - but compatible to just about any SOAP client out there --> great for interoperability, weak on features and security

  • wsHttpBinding is the full-blown binding, which supports a ton of WS-* features and standards - it has lots more security features, you can use sessionful connections, you can use reliable messaging, you can use transactional control - just a lot more stuff, but wsHttpBinding is also a lot *heavier" and adds a lot of overhead to your messages as they travel across the network

For an in-depth comparison (including a table and code examples) between the two check out this codeproject article: Differences between BasicHttpBinding and WsHttpBinding

How do you access the value of an SQL count () query in a Java program

I have done it this way (example):

String query="SELECT count(t1.id) from t1, t2 where t1.id=t2.id and t2.email='"[email protected]"'";
int count=0;
try {
    ResultSet rs = DatabaseService.statementDataBase().executeQuery(query);
    while(rs.next())
        count=rs.getInt(1);
} catch (SQLException e) {
    e.printStackTrace();
} finally {
    //...
}

java - path to trustStore - set property doesn't work?

You have a typo - it is trustStore.

Apart from setting the variables with System.setProperty(..), you can also use

-Djavax.net.ssl.keyStore=path/to/keystore.jks

How to create a HTML Table from a PHP array?

   <table>
     <tr>
       <td>title</td>
       <td>price</td>
       <td>number</td>
     </tr>
     <? foreach ($shop as $row) : ?>
     <tr>
       <td><? echo $row[0]; ?></td>
       <td><? echo $row[1]; ?></td>
       <td><? echo $row[2]; ?></td>
     </tr>
     <? endforeach; ?>
   </table>

How to escape single quotes in MySQL

Maybe you could take a look at function QUOTE in the MySQL manual.

How to get JSON from webpage into Python script

All that the call to urlopen() does (according to the docs) is return a file-like object. Once you have that, you need to call its read() method to actually pull the JSON data across the network.

Something like:

jsonurl = urlopen(url)

text = json.loads(jsonurl.read())
print text

How to capture multiple repeated groups?

The key distinction is repeating a captured group instead of capturing a repeated group.

As you have already found out, the difference is that repeating a captured group captures only the last iteration. Capturing a repeated group captures all iterations.

In PCRE (PHP):

((?:\w+)+),?
Match 1, Group 1.    0-5      HELLO
Match 2, Group 1.    6-11     THERE
Match 3, Group 1.    12-20    BRUTALLY
Match 4, Group 1.    21-26    CRUEL
Match 5, Group 1.    27-32    WORLD

Since all captures are in Group 1, you only need $1 for substitution.

I used the following general form of this regular expression:

((?:{{RE}})+)

Example at regex101

Unable to run Java code with Intellij IDEA

If you are just opened a new java project then create a new folder src/ in the man project location.

Then cut and paste all your package in that folder.

Then Right click on src directory and select option Mark Directory As > Sources Root.

Darkening an image with CSS (In any shape)

if you want only the background-image to be affected, you can use a linear gradient to do that, just like this:

  background: linear-gradient(rgba(0, 0, 0, .5), rgba(0, 0, 0, .5)), url(IMAGE_URL);

If you want it darker, make the alpha value higher, else you want it lighter, make alpha lower

How can I use "." as the delimiter with String.split() in java

When splitting with a string literal delimiter, the safest way is to use the Pattern.quote() method:

String[] words = line.split(Pattern.quote("."));

As described by other answers, splitting with "\\." is correct, but quote() will do this escaping for you.

What is the main purpose of setTag() getTag() methods of View?

I'd like to add few words.

Although using get/setTag(Object) seems to be very useful in the particular case of a ViewHolder pattern, I'd recommend to think twice before using it in other cases. There is almost always another solution with better design.

The main reason is that code like that becomes unsupportable pretty quickly.

  • It is non-obvious for other developers what you designed to store as tag in the view. The methods setTag/getTag are not descriptive at all.

  • It just stores an Object, which requires to be cast when you want to getTag. You can get unexpected crashes later when you decide to change the type of stored object in the tag.

  • Here's a real-life story: We had a pretty big project with a lot of adapters, async operations with views and so on. One developer decided to set/getTag in his part of code, but another one had already set the tag to this view. In the end, someone couldn't find his own tag and was very confused. It cost us several hours to find the bug.

setTag(int key, Object tag) looks much better, cause you can generate unique keys for every tag (using id resources), but there is a significant restriction for Android < 4.0. From Lint docs:

Prior to Android 4.0, the implementation of View.setTag(int, Object) would store the objects in a static map, where the values were strongly referenced. This means that if the object contains any references pointing back to the context, the context (which points to pretty much everything else) will leak. If you pass a view, the view provides a reference to the context that created it. Similarly, view holders typically contain a view, and cursors are sometimes also associated with views.

How to get a table cell value using jQuery?

$('#mytable tr').each(function() {
    var customerId = $(this).find("td:first").html();    
});

What you are doing is iterating through all the trs in the table, finding the first td in the current tr in the loop, and extracting its inner html.

To select a particular cell, you can reference them with an index:

$('#mytable tr').each(function() {
    var customerId = $(this).find("td").eq(2).html();    
});

In the above code, I will be retrieving the value of the third row (the index is zero-based, so the first cell index would be 0)


Here's how you can do it without jQuery:

var table = document.getElementById('mytable'), 
    rows = table.getElementsByTagName('tr'),
    i, j, cells, customerId;

for (i = 0, j = rows.length; i < j; ++i) {
    cells = rows[i].getElementsByTagName('td');
    if (!cells.length) {
        continue;
    }
    customerId = cells[0].innerHTML;
}

?

How to debug Ruby scripts

All other answers already give almost everything... Just a little addition.

If you want some more IDE-like debugger (non-CLI) and are not afraid of using Vim as editor, I suggest Vim Ruby Debugger plugin for it.

Its documentation is pretty straightforward, so follow the link and see. In short, it allows you to set breakpoint at current line in editor, view local variables in nifty window on pause, step over/into — almost all usual debugger features.

For me it was pretty enjoyable to use this vim debugger for debugging a Rails app, although rich logger abilities of Rails almost eliminates the need for it.

.c vs .cc vs. .cpp vs .hpp vs .h vs .cxx

Historically, the first extensions used for C++ were .c and .h, exactly like for C. This caused practical problems, especially the .c which didn't allow build systems to easily differentiate C++ and C files.

Unix, on which C++ has been developed, has case sensitive file systems. So some used .C for C++ files. Other used .c++, .cc and .cxx. .C and .c++ have the problem that they aren't available on other file systems and their use quickly dropped. DOS and Windows C++ compilers tended to use .cpp, and some of them make the choice difficult, if not impossible, to configure. Portability consideration made that choice the most common, even outside MS-Windows.

Headers have used the corresponding .H, .h++, .hh, .hxx and .hpp. But unlike the main files, .h remains to this day a popular choice for C++ even with the disadvantage that it doesn't allow to know if the header can be included in C context or not. Standard headers now have no extension at all.

Additionally, some are using .ii, .ixx, .ipp, .inl for headers providing inline definitions and .txx, .tpp and .tpl for template definitions. Those are either included in the headers providing the definition, or manually in the contexts where they are needed.

Compilers and tools usually don't care about what extensions are used, but using an extension that they associate with C++ prevents the need to track out how to configure them so they correctly recognize the language used.

2017 edit: the experimental module support of Visual Studio recognize .ixx as a default extension for module interfaces, clang++ is recognizing .c++m, .cppm and .cxxm for the same purpose.

Convert String to Calendar Object in Java

SimpleDateFormat is great, just note that HH is different from hh when working with hours. HH will return 24 hour based hours and hh will return 12 hour based hours.

For example, the following will return 12 hour time:

SimpleDateFormat sdf = new SimpleDateFormat("hh:mm aa");

While this will return 24 hour time:

SimpleDateFormat sdf = new SimpleDateFormat("HH:mm");

How to log a method's execution time exactly in milliseconds?

NSDate *methodStart = [NSDate date];

/* ... Do whatever you need to do ... */

NSDate *methodFinish = [NSDate date];
NSTimeInterval executionTime = [methodFinish timeIntervalSinceDate:methodStart];
NSLog(@"executionTime = %f", executionTime);

Swift:

let methodStart = NSDate()

/* ... Do whatever you need to do ... */

let methodFinish = NSDate()
let executionTime = methodFinish.timeIntervalSinceDate(methodStart)
print("Execution time: \(executionTime)")

Swift3:

let methodStart = Date()

/* ... Do whatever you need to do ... */

let methodFinish = Date()
let executionTime = methodFinish.timeIntervalSince(methodStart)
print("Execution time: \(executionTime)")

Easy to use and has sub-millisecond precision.

Warning: Use the 'defaultValue' or 'value' props on <select> instead of setting 'selected' on <option>

Use defaultValue and onChange like this

const [myValue, setMyValue] = useState('');

<select onChange={(e) => setMyValue(e.target.value)} defaultValue={props.myprop}>
                    
       <option>Option 1</option>
       <option>Option 2</option>
       <option>Option 3</option>

</select>

How to remove an unpushed outgoing commit in Visual Studio?

Go to the Team Explorer tab then click Branches. In the branches select your branch from remotes/origin. For example, you want to reset your master branch. Right-click at the master branch in remotes/origin then select Reset then click Delete changes. This will reset your local branch and removes all locally committed changes.

What are Long-Polling, Websockets, Server-Sent Events (SSE) and Comet?

I have tried to make note about these and have collected and written examples from a java perspective.

HTTP for Java Developers

Reverse Ajax - Old style

Async Handling on server side

Reverse Ajax - New style

Server Sent Events

Putting it here for any java developer who is looking into the same subject.

Failed to resolve: com.google.firebase:firebase-core:16.0.1

Just add below code and update all firebase versions that will work

 implementation 'com.google.firebase:firebase-core:17.2.0'

Detecting request type in PHP (GET, POST, PUT or DELETE)

I used this code. It should work.

function get_request_method() {
    $request_method = strtolower($_SERVER['REQUEST_METHOD']);

    if($request_method != 'get' && $request_method != 'post') {
        return $request_method;
    }

    if($request_method == 'post' && isset($_POST['_method'])) {
        return strtolower($_POST['_method']);
    }

    return $request_method;
}

This above code will work with REST calls and will also work with html form

<form method="post">
    <input name="_method" type="hidden" value="delete" />
    <input type="submit" value="Submit">
</form>

operator << must take exactly one argument

If you define operator<< as a member function it will have a different decomposed syntax than if you used a non-member operator<<. A non-member operator<< is a binary operator, where a member operator<< is a unary operator.

// Declarations
struct MyObj;
std::ostream& operator<<(std::ostream& os, const MyObj& myObj);

struct MyObj
{
    // This is a member unary-operator, hence one argument
    MyObj& operator<<(std::ostream& os) { os << *this; return *this; }

    int value = 8;
};

// This is a non-member binary-operator, 2 arguments
std::ostream& operator<<(std::ostream& os, const MyObj& myObj)
{
    return os << myObj.value;
}

So.... how do you really call them? Operators are odd in some ways, I'll challenge you to write the operator<<(...) syntax in your head to make things make sense.

MyObj mo;

// Calling the unary operator
mo << std::cout;

// which decomposes to...
mo.operator<<(std::cout);

Or you could attempt to call the non-member binary operator:

MyObj mo;

// Calling the binary operator
std::cout << mo;

// which decomposes to...
operator<<(std::cout, mo);

You have no obligation to make these operators behave intuitively when you make them into member functions, you could define operator<<(int) to left shift some member variable if you wanted to, understand that people may be a bit caught off guard, no matter how many comments you may write.

Almost lastly, there may be times where both decompositions for an operator call are valid, you may get into trouble here and we'll defer that conversation.

Lastly, note how odd it might be to write a unary member operator that is supposed to look like a binary operator (as you can make member operators virtual..... also attempting to not devolve and run down this path....)

struct MyObj
{
    // Note that we now return the ostream
    std::ostream& operator<<(std::ostream& os) { os << *this; return os; }

    int value = 8;
};

This syntax will irritate many coders now....

MyObj mo;

mo << std::cout << "Words words words";

// this decomposes to...
mo.operator<<(std::cout) << "Words words words";

// ... or even further ...
operator<<(mo.operator<<(std::cout), "Words words words");

Note how the cout is the second argument in the chain here.... odd right?

Search and replace part of string in database

I would consider writing a CLR replace function with RegEx support for this kind of string manipulation.

Why is python setup.py saying invalid command 'bdist_wheel' on Travis CI?

This error is weird as many proposed answers and got mixed solutions. I tried them, add them. It was only when I added pip install --upgrade pip finally removed the error for me. But I have no time to isolate which is which,so this is just fyi.

Escape single quote character for use in an SQLite query

Just in case if you have a loop or a json string that need to insert in the database. Try to replace the string with a single quote . here is my solution. example if you have a string that contain's a single quote.

String mystring = "Sample's";
String myfinalstring = mystring.replace("'","''");

 String query = "INSERT INTO "+table name+" ("+field1+") values ('"+myfinalstring+"')";

this works for me in c# and java

How to change a field name in JSON using Jackson

Have you tried using @JsonProperty?

@Entity
public class City {
   @id
   Long id;
   String name;

   @JsonProperty("label")
   public String getName() { return name; }

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

   @JsonProperty("value")
   public Long getId() { return id; }

   public void setId(Long id){ this.id = id; }
}

how to execute php code within javascript

Any server side stuff such as php declaration must get evaluated in the host file (file with a .php extension) inside the script tags such as below

<script type="text/javascript">
    var1 = "<?php echo 'Hello';?>";
</script>

Then in the .js file, you can use the variable

alert(var1);

If you try to evaluate php declaration in the .js file, it will NOT work

How to start http-server locally

When you're running npm install in the project's root, it installs all of the npm dependencies into the project's node_modules directory.

If you take a look at the project's node_modules directory, you should see a directory called http-server, which holds the http-server package, and a .bin folder, which holds the executable binaries from the installed dependencies. The .bin directory should have the http-server binary (or a link to it).

So in your case, you should be able to start the http-server by running the following from your project's root directory (instead of npm start):

./node_modules/.bin/http-server -a localhost -p 8000 -c-1

This should have the same effect as running npm start.

If you're running a Bash shell, you can simplify this by adding the ./node_modules/.bin folder to your $PATH environment variable:

export PATH=./node_modules/.bin:$PATH

This will put this folder on your path, and you should be able to simply run

http-server -a localhost -p 8000 -c-1

ng: command not found while creating new project using angular-cli

soluton for windows operating system only....... first step:

install nodejs version: nodev 8.1.2

second step: set up environment variable like: C:\ProgramFiles\nodejs

Third step: install angular use this command: npm install -g @angular/cli

after installation whereever you have to create project like: ng new first-project......

How do I handle a click anywhere in the page, even when a certain element stops the propagation?

I think this is what you need:

$("body").trigger("click");

This will allow you to trigger the body click event from anywhere.

How do I prevent CSS inheritance?

You could use something like jQuery to "disable" this behaviour, though I hardly think it's a good solution as you get display logic in css & javascript. Still, depending upon your requirements you might find jQuery's css utils make life easier for you than trying hacky css, especially if you're trying to make it work for IE6

How to add parameters to HttpURLConnection using POST using NameValuePair

I think I found exactly what you need. It may help others.

You can use the method UrlEncodedFormEntity.writeTo(OutputStream).

UrlEncodedFormEntity formEntity = new UrlEncodedFormEntity(nvp); 
http.connect();

OutputStream output = null;
try {
  output = http.getOutputStream();    
  formEntity.writeTo(output);
} finally {
 if (output != null) try { output.close(); } catch (IOException ioe) {}
}

How to use Bootstrap 4 in ASP.NET Core

Unfortunately, you're going to have a hard time using NuGet to install Bootstrap (or most other JavaScript/CSS frameworks) on a .NET Core project. If you look at the NuGet install it tells you it is incompatible:

enter image description here

if you must know where local packages dependencies are, they are now in your local profile directory. i.e. %userprofile%\.nuget\packages\bootstrap\4.0.0\content\Scripts.

However, I suggest switching to npm, or bower - like in Saineshwar's answer.

Deep copy of a dict in python

Python 3.x

from copy import deepcopy

my_dict = {'one': 1, 'two': 2}
new_dict_deepcopy = deepcopy(my_dict)

Without deepcopy, I am unable to remove the hostname dictionary from within my domain dictionary.

Without deepcopy I get the following error:

"RuntimeError: dictionary changed size during iteration"

...when I try to remove the desired element from my dictionary inside of another dictionary.

import socket
import xml.etree.ElementTree as ET
from copy import deepcopy

domain is a dictionary object

def remove_hostname(domain, hostname):
    domain_copy = deepcopy(domain)
    for domains, hosts in domain_copy.items():
        for host, port in hosts.items():
           if host == hostname:
                del domain[domains][host]
    return domain

Example output: [orginal]domains = {'localdomain': {'localhost': {'all': '4000'}}}

[new]domains = {'localdomain': {} }}

So what's going on here is I am iterating over a copy of a dictionary rather than iterating over the dictionary itself. With this method, you are able to remove elements as needed.

Why can't I define my workbook as an object?

You'll need to open the workbook to refer to it.

Sub Setwbk()

    Dim wbk As Workbook

    Set wbk = Workbooks.Open("F:\Quarterly Reports\2012 Reports\New Reports\ _
        Master Benchmark Data Sheet.xlsx")

End Sub

* Follow Doug's answer if the workbook is already open. For the sake of making this answer as complete as possible, I'm including my comment on his answer:

Why do I have to "set" it?

Set is how VBA assigns object variables. Since a Range and a Workbook/Worksheet are objects, you must use Set with these.

Laravel stylesheets and javascript don't load for non-base routes

You are using relative paths for your assets, change to an absolute path and everything will work (add a slash before "css".

<link rel="stylesheet" href="/css/app.css" />

Jquery function return value

The return statement you have is stuck in the inner function, so it won't return from the outer function. You just need a little more code:

function getMachine(color, qty) {
    var returnValue = null;
    $("#getMachine li").each(function() {
        var thisArray = $(this).text().split("~");
        if(thisArray[0] == color&& qty>= parseInt(thisArray[1]) && qty<= parseInt(thisArray[2])) {
            returnValue = thisArray[3];
            return false; // this breaks out of the each
        }
    });
    return returnValue;
}

var retval = getMachine(color, qty);

Flatten List in LINQ

If you have a List<List<int>> k you can do

List<int> flatList= k.SelectMany( v => v).ToList();

How to debug PDO database queries?

An old post but perhaps someone will find this useful;

function pdo_sql_debug($sql,$placeholders){
    foreach($placeholders as $k => $v){
        $sql = preg_replace('/:'.$k.'/',"'".$v."'",$sql);
    }
    return $sql;
}

How can I switch my git repository to a particular commit

How can I roll back my previous 4 commits locally in a branch?

Which means, you are not creating new branch and going into detached state. New way of doing that is:

git switch --detach revison

How to convert number of minutes to hh:mm format in TSQL?

DECLARE @Duration int

SET @Duration= 12540 /* for example big hour amount in minutes -> 209h */

SELECT CAST( CAST((@Duration) AS int) / 60 AS varchar) + ':'  + right('0' + CAST(CAST((@Duration) AS int) % 60 AS varchar(2)),2)

/* you will get hours and minutes divided by : */

PHP UML Generator

Here's how I did it (directly from code to PDF drawing without manual drawing of anything):

  1. Use BOUML for "reverse engineering PHP code" [sic] to extract the class model (BOUML is available from "universe" repository of Ubuntu). I seriously recommend BOUML for this step because it's really fast compared to many other programs I have tried. In addition, it seems that BOUML seems to extract the model correctly (for the parts that BOUML even tries to extract).
  2. Use BOUML to export model as XMI 1.4 file
  3. Use ArgoUML to import said XMI file (you can use webstart version for this step)
  4. Export XMI from ArgoUML (I don't know which XMI version/variant the output is but it is not the same result as the output from BOUML. The argouml-graphviz cannot handle XMI file directly from BOUML).
  5. Use argouml-graphviz to convert ArgoUML exported XMI file to dot format (you may need to use saxon instead of xsltproc to get it work due to use of XSLT2)
  6. Use dot or fdp or sfdp to render the class diagram.

Here's an example of suitable command line for using fdp to output PDF diagram (assuming that dot file generated by argouml-graphviz XLST processing is saved as xmi-model.dot):

fdp -Tpdf -Gmaxiter=1000 -Gmindist=0.5 -Gpackmode=node \
  -Eweight=0.05 -Elen=1.0 -Eminlen=1.0 -Gsplines=true \
  -Goverlap=false xmi-model.dot -oxmi-model.pdf

As an alternative you could try PHP_UML or php2xmi instead of BOUML for doing the "reverse engineering" part. I haven't yet tried that.

(I'm using the phrase "reverse engineering" because it seems that UML people are using those words when they mean extracting class and method information from the source code. I would personally interpret those words as extracting information from executable binary file or captured raw wire data.)

If you prefer drawing the class diagram by hand (instead of using computer to do all the drawing), you can use either BOUML or ArgoUML for the drawing. Using the "reverse engineered" data via BOUML will help in that case.