Programs & Examples On #Yui editor

Cannot lower case button text in android studio

<style name="AppTheme" parent="AppBaseTheme">
    <item name="android:buttonStyle">@style/Button</item>
</style>

<style name="Button" parent="Widget.AppCompat.Button">
    <item name="android:textAllCaps">false</item>
</style>

select rows in sql with latest date for each ID repeated multiple times

Here's one way. The inner query gets the max date for each id. Then you can join that back to your main table to get the rows that match.

select
*
from
<your table>
inner join 
(select id, max(<date col> as max_date) m
where yourtable.id = m.id
and yourtable.datecolumn = m.max_date)

How to insert element into arrays at specific position?

This is an old question, but I posted a comment in 2014 and frequently come back to this. I thought I would leave a full answer. This isn't the shortest solution but it is quite easy to understand.

Insert a new value into an associative array, at a numbered position, preserving keys, and preserving order.

$columns = array(
    'id' => 'ID',
    'name' => 'Name',
    'email' => 'Email',
    'count' => 'Number of posts'
);

$columns = array_merge(
    array_slice( $columns, 0, 3, true ),     // The first 3 items from the old array
    array( 'subscribed' => 'Subscribed' ),   // New value to add after the 3rd item
    array_slice( $columns, 3, null, true )   // Other items after the 3rd
);

print_r( $columns );

/*
Array ( 
    [id] => ID 
    [name] => Name 
    [email] => Email 
    [subscribed] => Subscribed 
    [count] => Number of posts 
)
*/

SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens on line 102

You didn't bind all your bindings here

$sql = "SELECT SQL_CALC_FOUND_ROWS *, UNIX_TIMESTAMP(publicationDate) AS publicationDate     FROM comments WHERE articleid = :art 
ORDER BY " . mysqli_escape_string($order) . " LIMIT :numRows";

$st = $conn->prepare( $sql );
$st->bindValue( ":art", $art, PDO::PARAM_INT );

You've declared a binding called :numRows but you never actually bind anything to it.

UPDATE 2019: I keep getting upvotes on this and that reminded me of another suggestion

Double quotes are string interpolation in PHP, so if you're going to use variables in a double quotes string, it's pointless to use the concat operator. On the flip side, single quotes are not string interpolation, so if you've only got like one variable at the end of a string it can make sense, or just use it for the whole string.

In fact, there's a micro op available here since the interpreter doesn't care about parsing the string for variables. The boost is nearly unnoticable and totally ignorable on a small scale. However, in a very large application, especially good old legacy monoliths, there can be a noticeable performance increase if strings are used like this. (and IMO, it's easier to read anyway)

How to fast get Hardware-ID in C#?

Here is a DLL that shows:
* Hard drive ID (unique hardware serial number written in drive's IDE electronic chip)
* Partition ID (volume serial number)
* CPU ID (unique hardware ID)
* CPU vendor
* CPU running speed
* CPU theoretic speed
* Memory Load ( Total memory used in percentage (%) )
* Total Physical ( Total physical memory in bytes )
* Avail Physical ( Physical memory left in bytes )
* Total PageFile ( Total page file in bytes )
* Available PageFile( Page file left in bytes )
* Total Virtual( Total virtual memory in bytes )
* Available Virtual ( Virtual memory left in bytes )
* Bios unique identification numberBiosDate
* Bios unique identification numberBiosVersion
* Bios unique identification numberBiosProductID
* Bios unique identification numberBiosVideo

(text grabbed from original web site)
It works with C#.

How to query nested objects?

Since there is a lot of confusion about queries MongoDB collection with sub-documents, I thought its worth to explain the above answers with examples:

First I have inserted only two objects in the collection namely: message as:

> db.messages.find().pretty()
{
    "_id" : ObjectId("5cce8e417d2e7b3fe9c93c32"),
    "headers" : {
        "From" : "[email protected]"
    }
}
{
    "_id" : ObjectId("5cce8eb97d2e7b3fe9c93c33"),
    "headers" : {
        "From" : "[email protected]",
        "To" : "[email protected]"
    }
}
>

So what is the result of query: db.messages.find({headers: {From: "[email protected]"} }).count()

It should be one because these queries for documents where headers equal to the object {From: "[email protected]"}, only i.e. contains no other fields or we should specify the entire sub-document as the value of a field.

So as per the answer from @Edmondo1984

Equality matches within sub-documents select documents if the subdocument matches exactly the specified sub-document, including the field order.

From the above statements, what is the below query result should be?

> db.messages.find({headers: {To: "[email protected]", From: "[email protected]"}  }).count()
0

And what if we will change the order of From and To i.e same as sub-documents of second documents?

> db.messages.find({headers: {From: "[email protected]", To: "[email protected]"}  }).count()
1

so, it matches exactly the specified sub-document, including the field order.

For using dot operator, I think it is very clear for every one. Let's see the result of below query:

> db.messages.find( { 'headers.From': "[email protected]" }  ).count()
2

I hope these explanations with the above example will make someone more clarity on find query with sub-documents.

Page unload event in asp.net

With AutoEventWireup which is turned on by default on a page you can just add methods prepended with **Page_***event* and have ASP.NET connect to the events for you.

In the case of Unload the method signature is:

protected void Page_Unload(object sender, EventArgs e)

For details see the MSDN article.

Error: stray '\240' in program

I got the same error when I just copied the complete line but when I rewrite the code again i.e. instead of copy-paste, writing it completely then the error was no longer present.

Conclusion: There might be some unacceptable words to the language got copied giving rise to this error.

JQuery Datatables : Cannot read property 'aDataSort' of undefined

I got the error by having multiple tables on the page and trying to initialize them all at once like this:

$('table').DataTable();

After a lot of trial and error, I initialized them separately and the error went away:

$("#table1-id").DataTable();
$("#table2-id").DataTable();

Why does Boolean.ToString output "True" and not "true"

This probably harks from the old VB NOT .Net days when bool.ToString produced True or False.

Concatenating elements in an array to a string

Use the Arrays.toString() function. It keeps your code short and readable. It uses a string builder internally, thus, it's also efficient. To get rid of the extra characters, you might chose to eliminate them using the String.replace() function, which, admittedly, reduces readability again.

String str = Arrays.toString(arr).replaceAll(", |\\[|\\]", "");

This is similar to the answer of Tris Nefzger, but without the lengthy substring construction to get rid of the square brackets.

Explanation of the Regex: "|" means any of ", " and "[" and "]". The "\\" tells the Java String that we are not meaning some special character (like a new line "\n" or a tab "\t") but a real backslash "\". So instead of "\\[", the Regex interpreter reads "\[", which tells it that we mean a literal square bracket and do not want to use it as part of the Regex language (for instance, "[^3]*" denotes any number of characters, but none of them should be "3").

How do I left align these Bootstrap form items?

Instead of altering the original bootstrap css class create a new css file that will override the default style.

Make sure you include the new css file after including the bootstrap.css file.

In the new css file do

.form-horizontal .control-label{
   text-align:left !important; 
}

No 'Access-Control-Allow-Origin' header is present on the requested resource- AngularJS

If you are using chrome: try open chrome with the args to disable web security like you see here:

Disable same origin policy in Chrome

How to run mvim (MacVim) from Terminal?

I don't think I'd to add anything to the path, did

brew install macvim

mvim -v

should then open macvim in the terminal, you can also go ahead and alias that

alias vim='mvim -v'

Swap two items in List<T>

If order matters, you should keep a property on the "T" objects in your list that denotes sequence. In order to swap them, just swap the value of that property, and then use that in the .Sort(comparison with sequence property)

Finding Number of Cores in Java

This works on Windows with Cygwin installed:

System.getenv("NUMBER_OF_PROCESSORS")

Plugin org.apache.maven.plugins:maven-compiler-plugin or one of its dependencies could not be resolved

I also got the same issue and not able to create a jar, and I found that in Windows-->Prefernces-->Java-->installed JREs By default JRE was added to the build path of newly created java project so just changed it to your prefered JDK.

Writing MemoryStream to Response Object

The problem for me was that my stream was not set to the origin before download.

Response.Clear();
Response.ContentType = "Application/msword";
Response.AddHeader("Content-Disposition", "attachment; filename=myfile.docx");

//ADDED THIS LINE
myMemoryStream.Seek(0,SeekOrigin.Begin);

myMemoryStream.WriteTo(Response.OutputStream); 
Response.Flush();
Response.Close();

Mail not sending with PHPMailer over SSL using SMTP

First, Google created the "use less secure accounts method" function:

https://myaccount.google.com/security

Then created the another permission:

https://accounts.google.com/b/0/DisplayUnlockCaptcha

Hope it helps.

How to save image in database using C#

Since you are using SQL, would recommend against using adhoc ('writing statements in strings'), especially given that you are loading an image.

ADO.NET can do all of the hard work of mapping, escaping etc for you.

Either create a Stored Procedure, or use SqlParameter to do the binding.

As the other posters say, use VARBINARY(MAX) as your storage type - IMAGE is being depracated.

How to upload (FTP) files to server in a bash script?

use this to upload a file to a remote location

#!/bin/bash
#$1 is the file name
#usage:this_script <filename>
HOST='your host'
USER="your user"
PASSWD="pass"
FILE="abc.php"
REMOTEPATH='/html'

ftp -n $HOST <<END_SCRIPT
quote USER $USER
quote PASS $PASSWD
cd $REMOTEPATH
put $FILE 
quit
END_SCRIPT
exit 0

Unicode (UTF-8) reading and writing to files in Python

You can also improve the original open() function to work with Unicode files by replacing it in place, using the partial function. The beauty of this solution is you don't need to change any old code. It's transparent.

import codecs
import functools
open = functools.partial(codecs.open, encoding='utf-8')

Android. Fragment getActivity() sometimes returns null

I've been battling this kind of problem for a while, and I think I've come up with a reliable solution.

It's pretty difficult to know for sure that this.getActivity() isn't going to return null for a Fragment, especially if you're dealing with any kind of network behaviour which gives your code ample time to withdraw Activity references.

In the solution below, I declare a small management class called the ActivityBuffer. Essentially, this class deals with maintaining a reliable reference to an owning Activity, and promising to execute Runnables within a valid Activity context whenever there's a valid reference available. The Runnables are scheduled for execution on the UI Thread immediately if the Context is available, otherwise execution is deferred until that Context is ready.

/** A class which maintains a list of transactions to occur when Context becomes available. */
public final class ActivityBuffer {

    /** A class which defines operations to execute once there's an available Context. */
    public interface IRunnable {
        /** Executes when there's an available Context. Ideally, will it operate immediately. */
        void run(final Activity pActivity);
    }

    /* Member Variables. */
    private       Activity        mActivity;
    private final List<IRunnable> mRunnables;

    /** Constructor. */
    public ActivityBuffer() {
        // Initialize Member Variables.
        this.mActivity  = null;
        this.mRunnables = new ArrayList<IRunnable>();
    }

    /** Executes the Runnable if there's an available Context. Otherwise, defers execution until it becomes available. */
    public final void safely(final IRunnable pRunnable) {
        // Synchronize along the current instance.
        synchronized(this) {
            // Do we have a context available?
            if(this.isContextAvailable()) {
                // Fetch the Activity.
                final Activity lActivity = this.getActivity();
                // Execute the Runnable along the Activity.
                lActivity.runOnUiThread(new Runnable() { @Override public final void run() { pRunnable.run(lActivity); } });
            }
            else {
                // Buffer the Runnable so that it's ready to receive a valid reference.
                this.getRunnables().add(pRunnable);
            }
        }
    }

    /** Called to inform the ActivityBuffer that there's an available Activity reference. */
    public final void onContextGained(final Activity pActivity) {
        // Synchronize along ourself.
        synchronized(this) {
            // Update the Activity reference.
            this.setActivity(pActivity);
            // Are there any Runnables awaiting execution?
            if(!this.getRunnables().isEmpty()) {
                // Iterate the Runnables.
                for(final IRunnable lRunnable : this.getRunnables()) {
                    // Execute the Runnable on the UI Thread.
                    pActivity.runOnUiThread(new Runnable() { @Override public final void run() {
                        // Execute the Runnable.
                        lRunnable.run(pActivity);
                    } });
                }
                // Empty the Runnables.
                this.getRunnables().clear();
            }
        }
    }

    /** Called to inform the ActivityBuffer that the Context has been lost. */
    public final void onContextLost() {
        // Synchronize along ourself.
        synchronized(this) {
            // Remove the Context reference.
            this.setActivity(null);
        }
    }

    /** Defines whether there's a safe Context available for the ActivityBuffer. */
    public final boolean isContextAvailable() {
        // Synchronize upon ourself.
        synchronized(this) {
            // Return the state of the Activity reference.
            return (this.getActivity() != null);
        }
    }

    /* Getters and Setters. */
    private final void setActivity(final Activity pActivity) {
        this.mActivity = pActivity;
    }

    private final Activity getActivity() {
        return this.mActivity;
    }

    private final List<IRunnable> getRunnables() {
        return this.mRunnables;
    }

}

In terms of its implementation, we must take care to apply the life cycle methods to coincide with the behaviour described above by Pawan M:

public class BaseFragment extends Fragment {

    /* Member Variables. */
    private ActivityBuffer mActivityBuffer;

    public BaseFragment() {
        // Implement the Parent.
        super();
        // Allocate the ActivityBuffer.
        this.mActivityBuffer = new ActivityBuffer();
    }

    @Override
    public final void onAttach(final Context pContext) {
        // Handle as usual.
        super.onAttach(pContext);
        // Is the Context an Activity?
        if(pContext instanceof Activity) {
            // Cast Accordingly.
            final Activity lActivity = (Activity)pContext;
            // Inform the ActivityBuffer.
            this.getActivityBuffer().onContextGained(lActivity);
        }
    }

    @Deprecated @Override
    public final void onAttach(final Activity pActivity) {
        // Handle as usual.
        super.onAttach(pActivity);
        // Inform the ActivityBuffer.
        this.getActivityBuffer().onContextGained(pActivity);
    }

    @Override
    public final void onDetach() {
        // Handle as usual.
        super.onDetach();
        // Inform the ActivityBuffer.
        this.getActivityBuffer().onContextLost();
    }

    /* Getters. */
    public final ActivityBuffer getActivityBuffer() {
        return this.mActivityBuffer;
    }

}

Finally, in any areas within your Fragment that extends BaseFragment that you're untrustworthy about a call to getActivity(), simply make a call to this.getActivityBuffer().safely(...) and declare an ActivityBuffer.IRunnable for the task!

The contents of your void run(final Activity pActivity) are then guaranteed to execute along the UI Thread.

The ActivityBuffer can then be used as follows:

this.getActivityBuffer().safely(
  new ActivityBuffer.IRunnable() {
    @Override public final void run(final Activity pActivity) {
       // Do something with guaranteed Context.
    }
  }
);

How to start an Android application from the command line?

Example here.

Pasted below:

This is about how to launch android application from the adb shell.

Command: am

Look for invoking path in AndroidManifest.xml

Browser app::

# am start -a android.intent.action.MAIN -n com.android.browser/.BrowserActivity
Starting: Intent { action=android.intent.action.MAIN comp={com.android.browser/com.android.browser.BrowserActivity} }
Warning: Activity not started, its current task has been brought to the front

Settings app::

# am start -a android.intent.action.MAIN -n com.android.settings/.Settings
Starting: Intent { action=android.intent.action.MAIN comp={com.android.settings/com.android.settings.Settings} }

How do I add BundleConfig.cs to my project?

If you are using "MVC 5" you may not see the file, and you should follow these steps: http://www.techjunkieblog.com/2015/05/aspnet-mvc-empty-project-adding.html

If you are using "ASP.NET 5" it has stopped using "bundling and minification" instead was replaced by gulp, bower, and npm. More information see https://jeffreyfritz.com/2015/05/where-did-my-asp-net-bundles-go-in-asp-net-5/

What is the difference between & vs @ and = in angularJS

@: one-way binding

=: two-way binding

&: function binding

What is the default boolean value in C#?

The default value is indeed false.

However you can't use a local variable is it's not been assigned first.

You can use the default keyword to verify:

bool foo = default(bool);
if (!foo) { Console.WriteLine("Default is false"); }

How do I tell Gradle to use specific JDK version?

If you are using Kotlin DSL, then in build.gradle.kts add:

tasks.withType<JavaCompile> {
    options.isFork = true
    options.forkOptions.javaHome = File("C:\\bin\\jdk-13.0.1\\")
}

Of course, I'm assuming that you have Windows OS and javac compiler is in path C:\bin\jdk-13.0.1\bin\javac. For Linux OS will be similarly.

RegisterStartupScript from code behind not working when Update Panel is used

You need to use ScriptManager.RegisterStartupScript for Ajax.

protected void ButtonPP_Click(object sender, EventArgs e) {     if (radioBtnACO.SelectedIndex < 0)     {         string csname1 = "PopupScript";          var cstext1 = new StringBuilder();         cstext1.Append("alert('Please Select Criteria!')");          ScriptManager.RegisterStartupScript(this, GetType(), csname1,             cstext1.ToString(), true);     } } 

Python read in string from file and split it into values

>>> [[int(i) for i in line.strip().split(',')] for line in open('input.txt').readlines()]
[[995957, 16833579], [995959, 16777241], [995960, 16829368], [995961, 50431654]]

How do I use WPF bindings with RelativeSource?

If you want to bind to another property on the object:

{Binding Path=PathToProperty, RelativeSource={RelativeSource Self}}

If you want to get a property on an ancestor:

{Binding Path=PathToProperty,
    RelativeSource={RelativeSource AncestorType={x:Type typeOfAncestor}}}

If you want to get a property on the templated parent (so you can do 2 way bindings in a ControlTemplate)

{Binding Path=PathToProperty, RelativeSource={RelativeSource TemplatedParent}}

or, shorter (this only works for OneWay bindings):

{TemplateBinding Path=PathToProperty}

Multiple Java versions running concurrently under Windows

It should be possible changing setting the JAVA_HOME environment variable differently for specific applications.

When starting from the command line or from a batch script you can use set JAVA_HOME=C:\...\j2dskXXX to change the JAVA_HOME environment.

It is possible that you also need to change the PATH environment variable to use the correct java binary. To do this you can use set PATH=%JAVA_HOME%\bin;%PATH%.

Composer: Command Not Found

Your composer.phar command lacks the flag for executable, or it is not inside the path.

The first problem can be fixed with chmod +x composer.phar, the second by calling it as ./composer.phar -v.

You have to prefix executables that are not in the path with an explicit reference to the current path in Unix, in order to avoid going into a directory that has an executable file with an innocent name that looks like a regular command, but is not. Just think of a cat in the current directory that does not list files, but deletes them.

The alternative, and better, fix for the second problem would be to put the composer.phar file into a location that is mentioned in the path

Jquery post, response in new window

Use the write()-Method of the Popup's document to put your markup there:

$.post(url, function (data) {
    var w = window.open('about:blank');
    w.document.open();
    w.document.write(data);
    w.document.close();
});

Insert and set value with max()+1 problems

SELECT MAX(col) +1 is not safe -- it does not ensure that you aren't inserting more than one customer with the same customer_id value, regardless if selecting from the same table or any others. The proper way to ensure a unique integer value is assigned on insertion into your table in MySQL is to use AUTO_INCREMENT. The ANSI standard is to use sequences, but MySQL doesn't support them. An AUTO_INCREMENT column can only be defined in the CREATE TABLE statement:

CREATE TABLE `customers` (
  `customer_id` int(11) NOT NULL AUTO_INCREMENT,
  `firstname` varchar(45) DEFAULT NULL,
  `surname` varchar(45) DEFAULT NULL,
  PRIMARY KEY (`customer_id`)
)

That said, this worked fine for me on 5.1.49:

CREATE TABLE `customers` (
  `customer_id` int(11) NOT NULL DEFAULT '0',
  `firstname` varchar(45) DEFAULT NULL,
  `surname` varchar(45) DEFAULT NULL,
  PRIMARY KEY (`customer_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1$$

INSERT INTO customers VALUES (1, 'a', 'b');

INSERT INTO customers 
SELECT MAX(customer_id) + 1, 'jim', 'sock'
  FROM CUSTOMERS;

Create a text file for download on-the-fly

No need to store it anywhere. Just output the content with the appropriate content type.

<?php
    header('Content-type: text/plain');
?>Hello, world.

Add content-disposition if you wish to trigger a download prompt.

header('Content-Disposition: attachment; filename="default-filename.txt"');

Node.js: Gzip compression?

Use gzip compression

Gzip compressing can greatly decrease the size of the response body and hence increase the speed of a web app. Use the compression middleware for gzip compression in your Express app. For example:

var compression = require('compression');
var express = require('express')
var app = express()
app.use(compression())

List of All Folders and Sub-folders

As well as find listed in other answers, better shells allow both recurvsive globs and filtering of glob matches, so in zsh for example...

ls -lad **/*(/)

...lists all directories while keeping all the "-l" details that you want, which you'd otherwise need to recreate using something like...

find . -type d -exec ls -ld {} \;

(not quite as easy as the other answers suggest)

The benefit of find is that it's more independent of the shell - more portable, even for system() calls from within a C/C++ program etc..

PHP sessions that have already been started

If you want a new one, then do session_destroy() before starting it. To check if its set before starting it, call session_status() :

$status = session_status();
if($status == PHP_SESSION_NONE){
    //There is no active session
    session_start();
}else
if($status == PHP_SESSION_DISABLED){
    //Sessions are not available
}else
if($status == PHP_SESSION_ACTIVE){
    //Destroy current and start new one
    session_destroy();
    session_start();
}

I would avoid checking the global $_SESSION instead of I am calling the session_status() method since PHP implemented this function explicitly to:

Expose session status via new function, session_status This is for (PHP >=5.4.0)

Twitter API returns error 215, Bad Authentication Data

FOUND A SOLUTION - using the Abraham TwitterOAuth library. If you are using an older implementation, the following lines should be added after the new TwitterOAuth object is instantiated:

$connection->host = "https://api.twitter.com/1.1/";
$connection->ssl_verifypeer = TRUE;
$connection->content_type = 'application/x-www-form-urlencoded';

The first 2 lines are now documented in Abraham library Readme file, but the 3rd one is not. Also make sure that your oauth_version is still 1.0.

Here is my code for getting all user data from 'users/show' with a newly authenticated user and returning the user full name and user icon with 1.1 - the following code is implemented in the authentication callback file:

session_start();
require ('twitteroauth/twitteroauth.php');
require ('twitteroauth/config.php');

$consumer_key = '****************';
$consumer_secret = '**********************************';

$to = new TwitterOAuth($consumer_key, $consumer_secret);

$tok = $to->getRequestToken('http://exampleredirect.com?twitoa=1');

$token = $tok['oauth_token'];
$secret = $tok['oauth_token_secret'];

//save tokens to session
$_SESSION['ttok'] = $token;
$_SESSION['tsec'] = $secret;

$request_link = $to->getAuthorizeURL($token,TRUE);

header('Location: ' . $request_link);

The following code then is in the redirect after authentication and token request

if($_REQUEST['twitoa']==1){
    require ('twitteroauth/twitteroauth.php');
    require_once('twitteroauth/config.php');
    //Twitter Creds
    $consumer_key = '*****************';
    $consumer_secret = '************************************';

    $oauth_token = $_GET['oauth_token']; //ex Request vals->http://domain.com/twitter_callback.php?oauth_token=MQZFhVRAP6jjsJdTunRYPXoPFzsXXKK0mQS3SxhNXZI&oauth_verifier=A5tYHnAsbxf3DBinZ1dZEj0hPgVdQ6vvjBJYg5UdJI

    $ttok = $_SESSION['ttok'];
    $tsec = $_SESSION['tsec'];

    $to = new TwitterOAuth($consumer_key, $consumer_secret, $ttok, $tsec);
    $tok = $to->getAccessToken();
    $btok = $tok['oauth_token'];
    $bsec = $tok['oauth_token_secret'];
    $twit_u_id = $tok['user_id'];
    $twit_screen_name = $tok['screen_name'];

    //Twitter 1.1 DEBUG
    //print_r($tok);
    //echo '<br/><br/>';
    //print_r($to);
    //echo '<br/><br/>';
    //echo $btok . '<br/><br/>';
    //echo $bsec . '<br/><br/>';
    //echo $twit_u_id . '<br/><br/>';
    //echo $twit_screen_name . '<br/><br/>';

    $twit_screen_name=urlencode($twit_screen_name);
    $connection = new TwitterOAuth($consumer_key, $consumer_secret, $btok, $bsec);
    $connection->host = "https://api.twitter.com/1.1/";
    $connection->ssl_verifypeer = TRUE;
    $connection->content_type = 'application/x-www-form-urlencoded';
    $ucontent = $connection->get('users/show', array('screen_name' => $twit_screen_name));

    //echo 'connection:<br/><br/>';
    //print_r($connection);
    //echo '<br/><br/>';
    //print_r($ucontent);

    $t_user_name = $ucontent->name;
    $t_user_icon = $ucontent->profile_image_url;

    //echo $t_user_name.'<br/><br/>';
    //echo $t_user_icon.'<br/><br/>';
}

It took me way too long to figure this one out. Hope this helps someone!!

How to plot a subset of a data frame in R?

with(dfr[dfr$var3 < 155,], plot(var1, var2)) should do the trick.

Edit regarding multiple conditions:

with(dfr[(dfr$var3 < 155) & (dfr$var4 > 27),], plot(var1, var2))

Alternative to itoa() for converting integer to string C++?

Behind the scenes, lexical_cast does this:

std::stringstream str;
str << myint;
std::string result;
str >> result;

If you don't want to "drag in" boost for this, then using the above is a good solution.

Environment.GetFolderPath(...CommonApplicationData) is still returning "C:\Documents and Settings\" on Vista

Output on Ubuntu 9.10 -> Ubuntu 12.04 with mono 2.10.8.1:

SpecialFolder.ApplicationData: /home/$USER/.config
SpecialFolder.CommonApplicationData: /usr/share
SpecialFolder.ProgramFiles: 
SpecialFolder.DesktopDirectory: /home/$USER/Desktop
SpecialFolder.LocalApplicationData: /home/$USER/.local/share
SpecialFolder.MyDocuments: /home/$USER
SpecialFolder.System: 

SpecialFolder.Personal: /home/$USER

Output on Ubuntu 16.04 with mono 4.2.1

SpecialFolder.ApplicationData: /home/$USER/.config
SpecialFolder.CommonApplicationData: /usr/share
SpecialFolder.ProgramFiles:
SpecialFolder.DesktopDirectory: /home/$USER/Desktop
SpecialFolder.LocalApplicationData: /home/$USER/.local/share
SpecialFolder.MyDocuments: /home/$USER
SpecialFolder.Desktop: /home/$USER/Desktop
SpecialFolder.Personal: /home/$USER

SpecialFolder.System: 
SpecialFolder.Programs: 
SpecialFolder.Favorites: 
SpecialFolder.Startup: 
SpecialFolder.Recent: 
SpecialFolder.SendTo: 
SpecialFolder.StartMenu: 
SpecialFolder.MyMusic: /home/$USER/Music
SpecialFolder.MyVideos: /home/$USER/Videos
SpecialFolder.MyComputer: 
SpecialFolder.NetworkShortcuts: 
SpecialFolder.Fonts: /home/$USER/.fonts
SpecialFolder.Templates: /home/$USER/Templates
SpecialFolder.CommonStartMenu: 
SpecialFolder.CommonPrograms: 
SpecialFolder.CommonStartup: 
SpecialFolder.CommonDesktopDirectory: 
SpecialFolder.PrinterShortcuts: 
SpecialFolder.InternetCache: 
SpecialFolder.Cookies: 
SpecialFolder.History: 
SpecialFolder.Windows: 
SpecialFolder.MyPictures: /home/$USER/Pictures
SpecialFolder.UserProfile: /home/$USER
SpecialFolder.SystemX86: 
SpecialFolder.ProgramFilesX86: 
SpecialFolder.CommonProgramFiles: 
SpecialFolder.CommonProgramFilesX86: 
SpecialFolder.CommonTemplates: /usr/share/templates
SpecialFolder.CommonDocuments: 
SpecialFolder.CommonAdminTools: 
SpecialFolder.AdminTools: 
SpecialFolder.CommonMusic: 
SpecialFolder.CommonPictures: 
SpecialFolder.CommonVideos: 
SpecialFolder.Resources: 
SpecialFolder.LocalizedResources: 
SpecialFolder.CommonOemLinks: 
SpecialFolder.CDBurning: 

where $USER is the current user

Output on Ubuntu 16.04 using dotnet core (3.0.100)

ApplicationData: /home/$USER/.config
CommonApplicationData: /usr/share
ProgramFiles: 
DesktopDirectory: /home/$USER/Desktop
LocalApplicationData: /home/$USER/.local/share
MyDocuments: /home/$USER
System: 
Personal: /home/$USER

Output on Android 6 using Xamarin 7.2

Environment.SpecialFolder.ApplicationData: /data/user/0/$APPNAME/files/.config
Environment.SpecialFolder.CommonApplicationData: /usr/share
Environment.SpecialFolder.ProgramFiles: 
Environment.SpecialFolder.DesktopDirectory: /data/user/0/$APPNAME/files/Desktop
Environment.SpecialFolder.LocalApplicationData: /data/user/0/$APPNAME/files/.local/share
Environment.SpecialFolder.MyDocuments: /data/user/0/$APPNAME/files
Environment.SpecialFolder.Desktop: /data/user/0/$APPNAME/files/Desktop
Environment.SpecialFolder.Personal: /data/user/0/$APPNAME/files

Environment.SpecialFolder.Startup: 
Environment.SpecialFolder.Recent: 
Environment.SpecialFolder.SendTo: 
Environment.SpecialFolder.StartMenu: 
Environment.SpecialFolder.MyMusic: /data/user/0/$APPNAME/files/Music
Environment.SpecialFolder.MyVideos: /data/user/0/$APPNAME/files/Videos
Environment.SpecialFolder.MyComputer: 
Environment.SpecialFolder.NetworkShortcuts: 
Environment.SpecialFolder.Fonts: /data/user/0/$APPNAME/files/.fonts
Environment.SpecialFolder.Templates: /data/user/0/$APPNAME/files/Templates
Environment.SpecialFolder.CommonStartMenu: 
Environment.SpecialFolder.CommonPrograms: 
Environment.SpecialFolder.CommonStartup: 
Environment.SpecialFolder.CommonDesktopDirectory: 
Environment.SpecialFolder.PrinterShortcuts: 
Environment.SpecialFolder.InternetCache: 
Environment.SpecialFolder.Cookies: 
Environment.SpecialFolder.History: 
Environment.SpecialFolder.Windows: 
Environment.SpecialFolder.MyPictures: /data/user/0/$APPNAME/files/Pictures
Environment.SpecialFolder.UserProfile: /data/user/0/$APPNAME/files
Environment.SpecialFolder.SystemX86: 
Environment.SpecialFolder.ProgramFilesX86: 
Environment.SpecialFolder.CommonProgramFiles: 
Environment.SpecialFolder.CommonProgramFilesX86: 
Environment.SpecialFolder.CommonTemplates: /usr/share/templates
Environment.SpecialFolder.CommonDocuments: 
Environment.SpecialFolder.CommonAdminTools: 
Environment.SpecialFolder.AdminTools: 
Environment.SpecialFolder.CommonMusic: 
Environment.SpecialFolder.CommonPictures: 
Environment.SpecialFolder.CommonVideos: 
Environment.SpecialFolder.Resources: 
Environment.SpecialFolder.LocalizedResources: 
Environment.SpecialFolder.CommonOemLinks: 
Environment.SpecialFolder.CDBurning: 

Where $APPNAME is the name of your Xamarin application (eg. MyApp.Droid)

Output on iOS Simulator 10.3 using Xamarin 7.2

ApplicationData: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/.config
CommonApplicationData: /usr/share
ProgramFiles: /Applications
DesktopDirectory: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/Desktop
LocalApplicationData: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents
MyDocuments: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents
Desktop: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/Desktop
MyDocuments: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents
Startup: 
Recent: 
SendTo: 
StartMenu: 
MyMusic: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/Music
MyVideos: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/Videos
MyComputer: 
NetworkShortcuts: 
Fonts: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/.fonts
Templates: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/Templates
CommonStartMenu: 
CommonPrograms: 
CommonStartup: 
CommonDesktopDirectory: 
PrinterShortcuts: 
InternetCache: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Library/Caches
Cookies: 
History: 
Windows: 
MyPictures: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Documents/Pictures
UserProfile: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID
SystemX86: 
ProgramFilesX86: 
CommonProgramFiles: 
CommonProgramFilesX86: 
CommonTemplates: /usr/share/templates
CommonDocuments: 
CommonAdminTools: 
AdminTools: 
CommonMusic: 
CommonPictures: 
CommonVideos: 
Resources: /Users/$USER/Library/Developer/CoreSimulator/Devices/$DEVICEGUID/data/Containers/Data/Application/$APPLICATIONGUID/Library
LocalizedResources: 
CommonOemLinks: 
CDBurning: 

Where $DEVICEGUID is the simulator GUID (depending on the selected simulator)

Output on ipad 10.3 using Xamarin 7.2

SpecialFolder.MyDocuments: /var/mobile/Containers/Data/Application/$APPLICATIONGUID/Documents

Output on ipad 13.3 using Xamarin 16.4

SpecialFolder.MyDocuments: /var/mobile/Containers/Data/Application/$APPLICATIONGUID/Documents
SpecialFolder.UserProfile: /private/var/mobile/Containers/Data/Application/$APPLICATIONGUID/Documents

Output on windows 10 using .net core 3.1

SpecialFolder.MyDocuments: C:\Users\$USER\Documents

Output on Ubuntu 18.04 using .net core 3.1

SpecialFolder.MyDocuments: /home/$USER

Output on MacOS Catalina using .net core 3.1

SpecialFolder.MyDocuments: /Users/$USER

What's a redirect URI? how does it apply to iOS app for OAuth2.0?

Take a look at OAuth 2.0 playground.You will get an overview of the protocol.It is basically an environment(like any app) that shows you the steps involved in the protocol.

https://developers.google.com/oauthplayground/

How to check whether a pandas DataFrame is empty?

I prefer going the long route. These are the checks I follow to avoid using a try-except clause -

  1. check if variable is not None
  2. then check if its a dataframe and
  3. make sure its not empty

Here, DATA is the suspect variable -

DATA is not None and isinstance(DATA, pd.DataFrame) and not DATA.empty

Load and execute external js file in node.js with access to local variables?

If you are planning to load an external javascript file's functions or objects, load on this context using the following code – note the runInThisContext method:

var vm = require("vm");
var fs = require("fs");

var data = fs.readFileSync('./externalfile.js');
const script = new vm.Script(data);
script.runInThisContext();

// here you can use externalfile's functions or objects as if they were instantiated here. They have been added to this context. 

Calculate the number of business days between two dates?

Works and without loops

This method doesn't use any loops and is actually quite simple. It expands the date range to full weeks since we know that each week has 5 business days. It then uses a lookup table to find the number of business days to subtract from the start and end to get the right result. I've expanded out the calculation to help show what's going on, but the whole thing could be condensed into a single line if needed.

Anyway, this works for me and so I thought I'd post it here in case it might help others. Happy coding.

Calculation

  • t : Total number of days between dates (1 if min = max)
  • a + b : Extra days needed to expand total to full weeks
  • k : 1.4 is number of weekdays per week, i.e., (t / 7) * 5
  • c : Number of weekdays to subtract from the total
  • m : A lookup table used to find the value of "c" for each day of the week

Culture

Code assumes a Monday to Friday work week. For other cultures, such as Sunday to Thursday, you'll need to offset the dates prior to calculation.

Method

public int Weekdays(DateTime min, DateTime max) 
{       
        if (min.Date > max.Date) throw new Exception("Invalid date span");
        var t = (max.AddDays(1).Date - min.Date).TotalDays;
        var a = (int) min.DayOfWeek;
        var b = 6 - (int) max.DayOfWeek;
        var k = 1.4;
        var m = new int[]{0, 0, 1, 2, 3, 4, 5}; 
        var c = m[a] + m[b];
        return (int)((t + a + b) / k) - c;
}

At least one JAR was scanned for TLDs yet contained no TLDs

If one wants to have the conf\logging.properties read one must (see also here) dump this file into the Servers\Tomcat v7.0 Server at localhost-config\ folder and then add the lines :

-Djava.util.logging.config.file="${workspace_loc}\Servers\Tomcat v7.0 Server at localhost-config\logging.properties" -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager

to the VM arguments of the launch configuration one is using.

This may have taken a restart or two (or not) but finally I saw in the console in bright red :

FINE: No TLD files were found in [file:/C:/Dropbox/eclipse_workspaces/javaEE/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/ted2012/WEB-INF/lib/logback-classic-1.0.7.jar]. Consider adding the JAR to the tomcat.util.scan.DefaultJarScanner.jarsToSkip or org.apache.catalina.startup.TldConfig.jarsToSkip property in CATALINA_BASE/conf/catalina.properties file. //etc

I still don't know when exactly this FINE warning appears - does not appear immediately on tomcat launch EDIT: from the comment by @Stephan: "The FINE warning appears each time any change is done in the JSP file".


Bonus: To make the warning go away add in catalina.properties :

# Additional JARs (over and above the default JARs listed above) to skip when
# scanning for TLDs. The list must be a comma separated list of JAR file names.
org.apache.catalina.startup.TldConfig.jarsToSkip=logback-classic-1.0.7.jar,\
joda-time-2.1.jar,joda-time-2.1-javadoc.jar,mysql-connector-java-5.1.24-bin.jar,\
logback-core-1.0.7.jar,javax.servlet.jsp.jstl-api-1.2.1.jar

Mixed mode assembly is built against version ‘v2.0.50727' of the runtime

Please add attribute useLegacyV2RuntimeActivationPolicy="true" in your applications app.config file.

Old Value

  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.1"/>
  </startup>

New Value

  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.1"/>
  </startup>

It will solve your problem.

How to output an Excel *.xls file from classic ASP

You can always just export the HTML table to an XLS document. Excel does a pretty good job understanding HTML tables.

Another possiblitly is to export the HTML tables as a CSV or TSV file, but you would need to setup the formatting in your code. This isn't too difficult to accomplish.

There's some classes in the Microsoft.Office.Interop that allow you to create an Excel file programatically, but I have always found them to be a little clumsy. You can find a .NET version of creating a spreadsheet here, which should be pretty easy to modify for classic ASP.

As for .NET, I've always liked CarlosAG's Excel XML Writer Library. It has a nice generator so you can setup your Excel file, save it as an XML spreadsheet and it generates the code to do all the formatting and everything. I know it's not classic ASP, but I thought that I would throw it out there.


With what you're trying above, try adding the header:

"Content-Disposition", "attachment; filename=excelTest.xls"

See if that works. Also, I always use this for the content type:

  Response.ContentType = "application/octet-stream"
    Response.ContentType = "application/vnd.ms-excel"

SelectSingleNode returning null for known good xml node path using XPath

I strongly suspect the problem is to do with namespaces. Try getting rid of the namespace and you'll be fine - but obviously that won't help in your real case, where I'd assume the document is fixed.

I can't remember offhand how to specify a namespace in an XPath expression, but I'm sure that's the problem.

EDIT: Okay, I've remembered how to do it now. It's not terribly pleasant though - you need to create an XmlNamespaceManager for it. Here's some sample code that works with your sample document:

using System;
using System.Xml;

public class Test
{
    static void Main()
    {
        XmlDocument doc = new XmlDocument();
        XmlNamespaceManager namespaces = new XmlNamespaceManager(doc.NameTable);
        namespaces.AddNamespace("ns", "urn:hl7-org:v3");
        doc.Load("test.xml");
        XmlNode idNode = doc.SelectSingleNode("/My_RootNode/ns:id", namespaces);
        string msgID = idNode.Attributes["extension"].Value;
        Console.WriteLine(msgID);
    }
}

How to get full path of selected file on change of <input type=‘file’> using javascript, jquery-ajax?

For security reasons browsers do not allow this, i.e. JavaScript in browser has no access to the File System, however using HTML5 File API, only Firefox provides a mozFullPath property, but if you try to get the value it returns an empty string:

$('input[type=file]').change(function () {
    console.log(this.files[0].mozFullPath);
});

http://jsfiddle.net/SCK5A/

So don't waste your time.

edit: If you need the file's path for reading a file you can use the FileReader API instead. Here is a related question on SO: Preview an image before it is uploaded.

How to insert an object in an ArrayList at a specific position

This method Appends the specified element to the end of this list.

add(E e) //append element to the end of the arraylist.

This method Inserts the specified element at the specified position in this list.

void add(int index, E element) //inserts element at the given position in the array list.

This method Replaces the element at the specified position in this list with the specified element.

set(int index, E element) //Replaces the element at the specified position in this list with the specified element.
      

      

How do I convert date/time from 24-hour format to 12-hour AM/PM?

Use smaller h

// 24 hrs 
H:i 
// output 14:20

// 12 hrs 
h:i 
// output 2:20

What is default list styling (CSS)?

http://www.w3schools.com/tags/tag_ul.asp

ul { 
    display: block;
    list-style-type: disc;
    margin-top: 1em;
    margin-bottom: 1em;
    margin-left: 0;
    margin-right: 0;
    padding-left: 40px;
}

Adding a favicon to a static HTML page

If you add the favicon into the root/images folder with the name favicon.ico browser will automatically understand and get it as favicon.I tested and worked. your link must be www.website.com/images/favicon.ico

For more information look this answer:

Do you have to include <link rel="icon" href="favicon.ico" type="image/x-icon" />?

How to tell whether a point is to the right or left side of a line

The vector (y1 - y2, x2 - x1) is perpendicular to the line, and always pointing right (or always pointing left, if you plane orientation is different from mine).

You can then compute the dot product of that vector and (x3 - x1, y3 - y1) to determine if the point lies on the same side of the line as the perpendicular vector (dot product > 0) or not.

What's the difference between getPath(), getAbsolutePath(), and getCanonicalPath() in Java?

The best way I have found to get a feel for things like this is to try them out:

import java.io.File;
public class PathTesting {
    public static void main(String [] args) {
        File f = new File("test/.././file.txt");
        System.out.println(f.getPath());
        System.out.println(f.getAbsolutePath());
        try {
            System.out.println(f.getCanonicalPath());
        }
        catch(Exception e) {}
    }
}

Your output will be something like:

test\..\.\file.txt
C:\projects\sandbox\trunk\test\..\.\file.txt
C:\projects\sandbox\trunk\file.txt

So, getPath() gives you the path based on the File object, which may or may not be relative; getAbsolutePath() gives you an absolute path to the file; and getCanonicalPath() gives you the unique absolute path to the file. Notice that there are a huge number of absolute paths that point to the same file, but only one canonical path.

When to use each? Depends on what you're trying to accomplish, but if you were trying to see if two Files are pointing at the same file on disk, you could compare their canonical paths. Just one example.

How to access static resources when mapping a global front controller servlet on /*

'Static' files in App Engine aren't directly accessible by your app. You either need to upload them twice, or serve the static files yourself, rather than using a static handler.

How to submit http form using C#

You can use the HttpWebRequest class to do so.

Example here:

using System;
using System.Net;
using System.Text;
using System.IO;


    public class Test
    {
        // Specify the URL to receive the request.
        public static void Main (string[] args)
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create (args[0]);

            // Set some reasonable limits on resources used by this request
            request.MaximumAutomaticRedirections = 4;
            request.MaximumResponseHeadersLength = 4;
            // Set credentials to use for this request.
            request.Credentials = CredentialCache.DefaultCredentials;
            HttpWebResponse response = (HttpWebResponse)request.GetResponse ();

            Console.WriteLine ("Content length is {0}", response.ContentLength);
            Console.WriteLine ("Content type is {0}", response.ContentType);

            // Get the stream associated with the response.
            Stream receiveStream = response.GetResponseStream ();

            // Pipes the stream to a higher level stream reader with the required encoding format. 
            StreamReader readStream = new StreamReader (receiveStream, Encoding.UTF8);

            Console.WriteLine ("Response stream received.");
            Console.WriteLine (readStream.ReadToEnd ());
            response.Close ();
            readStream.Close ();
        }
    }

/*
The output from this example will vary depending on the value passed into Main 
but will be similar to the following:

Content length is 1542
Content type is text/html; charset=utf-8
Response stream received.
<html>
...
</html>

*/

Can HTTP POST be limitless?

POST allows for an arbitrary length of data to be sent to a server, but there are limitations based on timeouts/bandwidth etc.

I think basically, it's safer to assume that it's not okay to send lots of data.

When to use window.opener / window.parent / window.top

top, parent, opener (as well as window, self, and iframe) are all window objects.

  1. window.opener -> returns the window that opens or launches the current popup window.
  2. window.top -> returns the topmost window, if you're using frames, this is the frameset window, if not using frames, this is the same as window or self.
  3. window.parent -> returns the parent frame of the current frame or iframe. The parent frame may be the frameset window or another frame if you have nested frames. If not using frames, parent is the same as the current window or self

"Permission Denied" trying to run Python on Windows 10

Adding the Local Python Path before the WindowsApps resolved the problem.

Environment Variables > Path

Bash Python --Version

How to search for string in an array

Completing remark to Jimmy Pena's accepted answer

As SeanC points out, this must be a 1-D array.

The following example call demonstrates that the IsInArray() function cannot be called only for 1-dim arrays, but also for "flat" 2-dim arrays:

Sub TestIsInArray()
    Const SearchItem As String = "ghi"
    Debug.Print "SearchItem = '" & SearchItem & "'"
    '----
    'a) Test 1-dim array
    Dim Arr As Variant
    Arr = Split("abc,def,ghi,jkl", ",")
    Debug.Print "a) 1-dim array " & vbNewLine & "   " & Join(Arr, "|") & " ~~> " & IsInArray(SearchItem, Arr)
    '----
    
        '//quick tool to create a 2-dim 1-based array
        Dim v As Variant, vals As Variant                                       
        v = Array(Array("abc", "def", "dummy", "jkl", 5), _
                  Array("mno", "pqr", "stu", "ghi", "vwx"))
        v = Application.Index(v, 0, 0)  ' create 2-dim array (2 rows, 5 cols)
    
    'b) Test "flat" 2-dim arrays
    Debug.Print "b) ""flat"" 2-dim arrays "
    Dim i As Long
    For i = LBound(v) To UBound(v)
        'slice "flat" 2-dim arrays of one row each
        vals = Application.Index(v, i, 0)
        'check for findings
        Debug.Print Format(i, "   0"), Join(vals, "|") & " ~~> " & IsInArray(SearchItem, vals)
    Next i
End Sub
Function IsInArray(stringToBeFound As String, Arr As Variant) As Boolean
'Site: https://stackoverflow.com/questions/10951687/how-to-search-for-string-in-an-array/10952705
'Note: needs a "flat" array, not necessarily a 1-dimensioned array
  IsInArray = (UBound(Filter(Arr, stringToBeFound)) > -1)
End Function

Results in VB Editor's immediate window

SearchItem = 'ghi'
a) 1-dim array 
   abc|def|ghi|jkl ~~> Wahr
b) "flat" 2-dim arrays 
   1          abc|def|dummy|jkl|5         False
   2          mno|pqr|stu|ghi|vwx         True

Splitting a continuous variable into equal sized groups

Or see cut_number from the ggplot2 package, e.g.

das$wt_2 <- as.numeric(cut_number(das$wt,3))

Note that cut(...,3) divides the range of the original data into three ranges of equal lengths; it doesn't necessarily result in the same number of observations per group if the data are unevenly distributed (you can replicate what cut_number does by using quantile appropriately, but it's a nice convenience function). On the other hand, Hmisc::cut2() using the g= argument does split by quantiles, so is more or less equivalent to ggplot2::cut_number. I might have thought that something like cut_number would have made its way into dplyr by so far, but as far as I can tell it hasn't.

The differences between initialize, define, declare a variable

Declaration says "this thing exists somewhere":

int foo();       // function
extern int bar;  // variable
struct T
{
   static int baz;  // static member variable
};

Definition says "this thing exists here; make memory for it":

int foo() {}     // function
int bar;         // variable
int T::baz;      // static member variable

Initialisation is optional at the point of definition for objects, and says "here is the initial value for this thing":

int bar = 0;     // variable
int T::baz = 42; // static member variable

Sometimes it's possible at the point of declaration instead:

struct T
{
   static int baz = 42;
};

…but that's getting into more complex features.

How to initialize a vector with fixed length in R

The initialization method easiest to remember is

vec = vector(,10); #the same as "vec = vector(length = 10);"

The values of vec are: "[1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE" (logical mode) by default.

But after setting a character value, like

vec[2] = 'abc'

vec becomes: "FALSE" "abc" "FALSE" "FALSE" "FALSE" "FALSE" "FALSE" "FALSE" "FALSE" "FALSE"", which is of the character mode.

Read and Write CSV files including unicode with Python 2.7

Another alternative:

Use the code from the unicodecsv package ...

https://pypi.python.org/pypi/unicodecsv/

>>> import unicodecsv as csv
>>> from io import BytesIO
>>> f = BytesIO()
>>> w = csv.writer(f, encoding='utf-8')
>>> _ = w.writerow((u'é', u'ñ'))
>>> _ = f.seek(0)
>>> r = csv.reader(f, encoding='utf-8')
>>> next(r) == [u'é', u'ñ']
True

This module is API compatible with the STDLIB csv module.

Java to Jackson JSON serialization: Money fields

I had the same issue and i had it formatted into JSON as a String instead. Might be a bit of a hack but it's easy to implement.

private BigDecimal myValue = new BigDecimal("25.50");
...
public String getMyValue() {
    return myValue.setScale(2, BigDecimal.ROUND_HALF_UP).toString();
}

CSS image resize percentage of itself?

This is a very old thread but I found it while searching for a simple solution to display retina (high res) screen capture on standard resolution display.

So there is an HTML only solution for modern browsers :

<img srcset="image.jpg 100w" sizes="50px" src="image.jpg"/>

This is telling the browser that the image is twice the dimension of it intended display size. The value are proportional and do not need to reflect the actual size of the image. One can use 2w 1px as well to achieve the same effect. The src attribute is only used by legacy browsers.

The nice effect of it is that it display the same size on retina or standard display, shrinking on the latter.

Allow user to select camera or gallery for image

this code will help you, in that there is two button one for Camera and another for Gallery, and Image will be displayed in ImageView

https://github.com/siddhpuraamitr/Choose-Image-From-Gallery-Or-Camera

Read file content from S3 bucket with boto3

boto3 offers a resource model that makes tasks like iterating through objects easier. Unfortunately, StreamingBody doesn't provide readline or readlines.

s3 = boto3.resource('s3')
bucket = s3.Bucket('test-bucket')
# Iterates through all the objects, doing the pagination for you. Each obj
# is an ObjectSummary, so it doesn't contain the body. You'll need to call
# get to get the whole body.
for obj in bucket.objects.all():
    key = obj.key
    body = obj.get()['Body'].read()

PHP server on local machine?

AppServ is a small program in Windows to run:

  • Apache
  • PHP
  • MySQL
  • phpMyAdmin

It will also give you a startup and stop button for Apache. Which I find very useful.

:touch CSS pseudo-class or something similar?

I was having trouble with mobile touchscreen button styling. This will fix your hover-stick / active button problems.

_x000D_
_x000D_
body, html {
  width: 600px;
}
p {
  font-size: 20px;
}

button {
  border: none;
  width: 200px;
  height: 60px;
  border-radius: 30px;
  background: #00aeff;
  font-size: 20px;
}

button:active {
  background: black;
  color: white;
}

.delayed {
  transition: all 0.2s;
  transition-delay: 300ms;
}

.delayed:active {
  transition: none;
}
_x000D_
<h1>Sticky styles for better touch screen buttons!</h1>

<button>Normal button</button>

<button class="delayed"><a href="https://www.google.com"/>Delayed style</a></button>

<p>The CSS :active psuedo style is displayed between the time when a user touches down (when finger contacts screen) on a element to the time when the touch up (when finger leaves the screen) occures.   With a typical touch-screen tap interaction, the time of which the :active psuedo style is displayed can be very small resulting in the :active state not showing or being missed by the user entirely.  This can cause issues with users not undertanding if their button presses have actually reigstered or not.</p>

<p>Having the the :active styling stick around for a few hundred more milliseconds after touch up would would improve user understanding when they have interacted with a button.</p>
_x000D_
_x000D_
_x000D_

how to load CSS file into jsp

I had the same problem too. Then i realized that in the MainPageServlet the urlPatterns parameter in @WebServlet annotation contained "/", because i wanted to forward to the MainPage if the user entered the section www.site.com/ . When i tried to open the css file from the browser, the url was www.site.com/css/desktop.css, but the page content was THE PAGE MainPage.jsp. So, i removed the "/" urlPattern and now i can use CSS files in my jsp file using one of the most common solutions (${pageContext.request.contextPath}/css/desktop.css). Make sure your servlet doesn't contain the "/" urlPattern. I hope this worked for u too, - Axel Montini

Console.WriteLine and generic List

new List<int> { 1, 3, 5 }.ForEach(Console.WriteLine);

What's the difference between console.dir and console.log?

From the firebug site http://getfirebug.com/logging/

Calling console.dir(object) will log an interactive listing of an object's properties, like > a miniature version of the DOM tab.

UnmodifiableMap (Java Collections) vs ImmutableMap (Google)

ImmutableMap does not accept null values whereas Collections.unmodifiableMap() does. In addition it will never change after construction, while UnmodifiableMap may. From the JavaDoc:

An immutable, hash-based Map with reliable user-specified iteration order. Does not permit null keys or values.

Unlike Collections.unmodifiableMap(java.util.Map), which is a view of a separate map which can still change, an instance of ImmutableMap contains its own data and will never change. ImmutableMap is convenient for public static final maps ("constant maps") and also lets you easily make a "defensive copy" of a map provided to your class by a caller.

Compression/Decompression string with C#

according to this snippet i use this code and it's working fine:

using System;
using System.IO;
using System.IO.Compression;
using System.Text;

namespace CompressString
{
    internal static class StringCompressor
    {
        /// <summary>
        /// Compresses the string.
        /// </summary>
        /// <param name="text">The text.</param>
        /// <returns></returns>
        public static string CompressString(string text)
        {
            byte[] buffer = Encoding.UTF8.GetBytes(text);
            var memoryStream = new MemoryStream();
            using (var gZipStream = new GZipStream(memoryStream, CompressionMode.Compress, true))
            {
                gZipStream.Write(buffer, 0, buffer.Length);
            }

            memoryStream.Position = 0;

            var compressedData = new byte[memoryStream.Length];
            memoryStream.Read(compressedData, 0, compressedData.Length);

            var gZipBuffer = new byte[compressedData.Length + 4];
            Buffer.BlockCopy(compressedData, 0, gZipBuffer, 4, compressedData.Length);
            Buffer.BlockCopy(BitConverter.GetBytes(buffer.Length), 0, gZipBuffer, 0, 4);
            return Convert.ToBase64String(gZipBuffer);
        }

        /// <summary>
        /// Decompresses the string.
        /// </summary>
        /// <param name="compressedText">The compressed text.</param>
        /// <returns></returns>
        public static string DecompressString(string compressedText)
        {
            byte[] gZipBuffer = Convert.FromBase64String(compressedText);
            using (var memoryStream = new MemoryStream())
            {
                int dataLength = BitConverter.ToInt32(gZipBuffer, 0);
                memoryStream.Write(gZipBuffer, 4, gZipBuffer.Length - 4);

                var buffer = new byte[dataLength];

                memoryStream.Position = 0;
                using (var gZipStream = new GZipStream(memoryStream, CompressionMode.Decompress))
                {
                    gZipStream.Read(buffer, 0, buffer.Length);
                }

                return Encoding.UTF8.GetString(buffer);
            }
        }
    }
}

"Non-resolvable parent POM: Could not transfer artifact" when trying to refer to a parent pom from a child pom with ${parent.groupid}

Looks like you're trying to both inherit the groupId from the parent, and simultaneously specify the parent using an inherited groupId!

In the child pom, use something like this:

<modelVersion>4.0.0</modelVersion>

<parent>
  <groupId>org.felipe</groupId>
  <artifactId>tutorial_maven</artifactId>
  <version>1.0-SNAPSHOT</version>
  <relativePath>../pom.xml</relativePath>
</parent>

<artifactId>tutorial_maven_jar</artifactId>

Using properties like ${project.groupId} won't work there. If you specify the parent in this way, then you can inherit the groupId and version in the child pom. Hence, you only need to specify the artifactId in the child pom.

ElasticSearch - Return Unique Values

if you want to get the first document for each language field unique value, you can do this:

{
 "query": {
    "match_all": {
    }
  },
  "collapse": {
    "field": "language.keyword",
    "inner_hits": {
    "name": "latest",
      "size": 1
    }
  }
}

Open button in new window?

Opens a new window with the url you supplied :)

<button class="button" onClick="window.open('http://www.example.com');">
     <span class="icon">Open</span>
</button>

hope that helps :)

What is the "N+1 selects problem" in ORM (Object-Relational Mapping)?

Let's say you have a collection of Car objects (database rows), and each Car has a collection of Wheel objects (also rows). In other words, Car ? Wheel is a 1-to-many relationship.

Now, let's say you need to iterate through all the cars, and for each one, print out a list of the wheels. The naive O/R implementation would do the following:

SELECT * FROM Cars;

And then for each Car:

SELECT * FROM Wheel WHERE CarId = ?

In other words, you have one select for the Cars, and then N additional selects, where N is the total number of cars.

Alternatively, one could get all wheels and perform the lookups in memory:

SELECT * FROM Wheel

This reduces the number of round-trips to the database from N+1 to 2. Most ORM tools give you several ways to prevent N+1 selects.

Reference: Java Persistence with Hibernate, chapter 13.

Why can't I inherit static classes?

The main reason that you cannot inherit a static class is that they are abstract and sealed (this also prevents any instance of them from being created).

So this:

static class Foo { }

compiles to this IL:

.class private abstract auto ansi sealed beforefieldinit Foo
  extends [mscorlib]System.Object
 {
 }

Upload DOC or PDF using PHP

Don't use the ['type'] parameter to validate uploads. That field is user-provided, and can be trivially forged, allowing ANY type of file to be uploaded. The same goes for the ['name'] parameter - that's the name of the file as provided by the user. It is also trivial to forge, so the user's sending nastyvirus.exe and calling it cutekittens.jpg.

The proper method for validating uploads is to use server-side mime-type determination, e.g. via fileinfo, plus having proper upload success checking, which you do not:

if ($_FILES['file']['error'] !== UPLOAD_ERR_OK) {
    die("Upload failed with error " . $_FILES['file']['error']);
}
$finfo = finfo_open(FILEINFO_MIME_TYPE);
$mime = finfo_file($finfo, $_FILES['file']['tmp_name']);
$ok = false;
switch ($mime) {
   case 'image/jpeg':
   case 'application/pdf'
   case etc....
        $ok = true;
   default:
       die("Unknown/not permitted file type");
}
move_uploaded_file(...);

You are also using the user-provided filename as part of the final destination of the move_uploaded_files. it is also trivial to embed path data into that filename, which you then blindly use. That means a malicious remote user can scribble on ANY file on your server that they know the path for, plus plant new files.

Real differences between "java -server" and "java -client"?

I've not noticed any difference in startup time between the 2, but clocked a very minimal improvement in application performance with "-server" (Solaris server, everyone using SunRays to run the app). That was under 1.5.

Bootstrap change carousel height

Thank you! This post is Very Helpful. You may also want to add

object-fit:cover;

To preserve the aspect ration for different window sizes

.carousel .item {
  height: 500px;
}

.item img {
    position: absolute;
    object-fit:cover;
    top: 0;
    left: 0;
    min-height: 500px;
}

For bootstrap 4 and above replace .item with .carousel-item

.carousel .carousel-item {
  height: 500px;
}

.carousel-item img {
    position: absolute;
    object-fit:cover;
    top: 0;
    left: 0;
    min-height: 500px;
}

Is it more efficient to copy a vector by reserving and copying, or by creating and swapping?

Your second example does not work if you send the argument by reference. Did you mean

void copyVecFast(vec<int> original) // no reference
{

  vector<int> new_;
  new_.swap(original); 
}

That would work, but an easier way is

vector<int> new_(original);

How to compare two lists in python?

If you mean lists, try ==:

l1 = [1,2,3]
l2 = [1,2,3,4]

l1 == l2 # False

If you mean array:

l1 = array('l', [1, 2, 3])
l2 = array('d', [1.0, 2.0, 3.0])
l1 == l2 # True
l2 = array('d', [1.0, 2.0, 3.0, 4.0])
l1 == l2 # False

If you want to compare strings (per your comment):

date_string  = u'Thu Sep 16 13:14:15 CDT 2010'
date_string2 = u'Thu Sep 16 14:14:15 CDT 2010'
date_string == date_string2 # False

How to validate an Email in PHP?

Use:

var_dump(filter_var('[email protected]', FILTER_VALIDATE_EMAIL));
$validator = new EmailValidator();
$multipleValidations = new MultipleValidationWithAnd([
    new RFCValidation(),
    new DNSCheckValidation()
]);
$validator->isValid("[email protected]", $multipleValidations); //true

Java Switch Statement - Is "or"/"and" possible?

From what I understand about your question, before passing the character into the switch statement, you can convert it to lowercase. So you don't have to worry about upper cases because they are automatically converted to lower case. For that you need to use the below function:

Character.toLowerCase(c);

Count length of array and return 1 if it only contains one element

A couple other options:

  1. Use the comma operator to create an array:

    $cars = ,"bmw"
    $cars.GetType().FullName
    # Outputs: System.Object[]
    
  2. Use array subexpression syntax:

    $cars = @("bmw")
    $cars.GetType().FullName
    # Outputs: System.Object[]
    

If you don't want an object array you can downcast to the type you want e.g. a string array.

 [string[]] $cars = ,"bmw"
 [string[]] $cars = @("bmw")

Convert an object to an XML string

I realize this is a very old post, but after looking at L.B's response I thought about how I could improve upon the accepted answer and make it generic for my own application. Here's what I came up with:

public static string Serialize<T>(T dataToSerialize)
{
    try
    {
        var stringwriter = new System.IO.StringWriter();
        var serializer = new XmlSerializer(typeof(T));
        serializer.Serialize(stringwriter, dataToSerialize);
        return stringwriter.ToString();
    }
    catch
    {
        throw;
    }
}

public static T Deserialize<T>(string xmlText)
{
    try
    {
        var stringReader = new System.IO.StringReader(xmlText);
        var serializer = new XmlSerializer(typeof(T));
        return (T)serializer.Deserialize(stringReader);
    }
    catch
    {
        throw;
    }
}

These methods can now be placed in a static helper class, which means no code duplication to every class that needs to be serialized.

Show or hide element in React

If you would like to see how to TOGGLE the display of a component checkout this fiddle.

http://jsfiddle.net/mnoster/kb3gN/16387/

var Search = React.createClass({
    getInitialState: function() {
        return { 
            shouldHide:false
        };
    },
    onClick: function() {
        console.log("onclick");
        if(!this.state.shouldHide){
            this.setState({
                shouldHide: true 
            })
        }else{
                    this.setState({
                shouldHide: false 
            })
        }
    },
render: function() {
    return (
      <div>
        <button onClick={this.onClick}>click me</button>
        <p className={this.state.shouldHide ? 'hidden' : ''} >yoyoyoyoyo</p>
      </div>
    );
}
});

ReactDOM.render( <Search /> , document.getElementById('container'));

How to POST URL in data of a curl request

I don't think it's necessary to use semi-quotes around the variables, try:

curl -XPOST 'http://localhost/Service' -d "path=%2fxyz%2fpqr%2ftest%2f&fileName=1.doc"

%2f is the escape code for a /.

http://www.december.com/html/spec/esccodes.html

Also, do you need to specify a port? ( just checking :) )

Python memory leaks

This is by no means exhaustive advice. But number one thing to keep in mind when writing with the thought of avoiding future memory leaks (loops) is to make sure that anything which accepts a reference to a call-back, should store that call-back as a weak reference.

What is the difference between printf() and puts() in C?

puts is simpler than printf but be aware that the former automatically appends a newline. If that's not what you want, you can fputs your string to stdout or use printf.

SyntaxError: multiple statements found while compiling a single statement

A (partial) practical work-around is to put things into a throw-away function.

Pasting

x = 1
x += 1
print(x)

results in

>>> x = 1
x += 1
print(x)
  File "<stdin>", line 1
    x += 1
print(x)

    ^
SyntaxError: multiple statements found while compiling a single statement
>>>

However, pasting

def abc():
  x = 1
  x += 1
  print(x)

works:

>>> def abc():
  x = 1
  x += 1
  print(x)
>>> abc()
2
>>>

Of course, this is OK for a quick one-off, won't work for everything you might want to do, etc. But then, going to ipython / jupyter qtconsole is probably the next simplest option.

Pass object to javascript function

The "braces" are making an object literal, i.e. they create an object. It is one argument.

Example:

function someFunc(arg) {
    alert(arg.foo);
    alert(arg.bar);
}

someFunc({foo: "This", bar: "works!"});

the object can be created beforehand as well:

var someObject = {
    foo: "This", 
    bar: "works!"
};

someFunc(someObject);

I recommend to read the MDN JavaScript Guide - Working with Objects.

Html table with button on each row

Pretty sure this solves what you're looking for:

HTML:

<table>
    <tr><td><button class="editbtn">edit</button></td></tr>
    <tr><td><button class="editbtn">edit</button></td></tr>
    <tr><td><button class="editbtn">edit</button></td></tr>
    <tr><td><button class="editbtn">edit</button></td></tr>
</table>

Javascript (using jQuery):

$(document).ready(function(){
    $('.editbtn').click(function(){
        $(this).html($(this).html() == 'edit' ? 'modify' : 'edit');
    });
});

Edit:

Apparently I should have looked at your sample code first ;)

You need to change (at least) the ID attribute of each element. The ID is the unique identifier for each element on the page, meaning that if you have multiple items with the same ID, you'll get conflicts.

By using classes, you can apply the same logic to multiple elements without any conflicts.

JSFiddle sample

Permission is only granted to system app

To ignore this error for one instance only, add the tools:ignore="ProtectedPermissions" attribute to your permission declaration. Here is an example:

<uses-permission android:name="android.permission.READ_PRIVILEGED_PHONE_STATE"
    tools:ignore="ProtectedPermissions" />

You have to add tools namespace in the manifest root element

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"

How to get MAC address of your machine using a C program?

Assuming that c++ code (c++11) is okay as well and the interface is known.

#include <cstdint>
#include <fstream>
#include <streambuf>
#include <regex>

using namespace std;

uint64_t getIFMAC(const string &ifname) {
  ifstream iface("/sys/class/net/" + ifname + "/address");
  string str((istreambuf_iterator<char>(iface)), istreambuf_iterator<char>());
  if (str.length() > 0) {
    string hex = regex_replace(str, std::regex(":"), "");
    return stoull(hex, 0, 16);
  } else {
    return 0;
  }
} 
int main()
{
  string iface = "eth0";
  printf("%s: mac=%016llX\n", iface.c_str(), getIFMAC(iface));
}

Is it possible to use jQuery to read meta tags

For select twitter meta name , you can add a data attribute.

example :

meta name="twitter:card" data-twitterCard="" content=""
$('[data-twitterCard]').attr('content');

How to install numpy on windows using pip install?

Check installation of python 2.7 than install/reinstall pip which described here than open command line and write

pip install numpy

or

pip install scipy

if already installed try this

pip install -U numpy

Java Package Does Not Exist Error

Right click your maven project in bottom of the drop down list Maven >> reimport

it works for me for the missing dependancyies

How to show and update echo on same line

My favorite way is called do the sleep to 50. here i variable need to be used inside echo statements.

for i in $(seq 1 50); do
  echo -ne "$i%\033[0K\r"
  sleep 50
done
echo "ended"

How to remove array element in mongodb?

You can simply use $pull to remove a sub-document. The $pull operator removes from an existing array all instances of a value or values that match a specified condition.

Collection.update({
    _id: parentDocumentId
  }, {
    $pull: {
      subDocument: {
        _id: SubDocumentId
      }
    }
  });

This will find your parent document against given ID and then will remove the element from subDocument which matched the given criteria.

Read more about pull here.

Javascript : Send JSON Object with Ajax?

If you`re not using jQuery then please make sure:

var json_upload = "json_name=" + JSON.stringify({name:"John Rambo", time:"2pm"});
var xmlhttp = new XMLHttpRequest();   // new HttpRequest instance 
xmlhttp.open("POST", "/file.php");
xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xmlhttp.send(json_upload);

And for the php receiving end:

 $_POST['json_name'] 

Single vs Double quotes (' vs ")

If it's all the same, perhaps using single-quotes is better since it doesn't require holding down the shift key. Fewer keystrokes == less chance of RSI.

TypeError: 'NoneType' object is not iterable in Python

Another thing that can produce this error is when you are setting something equal to the return from a function, but forgot to actually return anything.

Example:

def foo(dict_of_dicts):
    for key, row in dict_of_dicts.items():
        for key, inner_row in row.items():
            Do SomeThing
    #Whoops, forgot to return all my stuff

return1, return2, return3 = foo(dict_of_dicts)

This is a little bit of a tough error to spot because the error can also be produced if the row variable happens to be None on one of the iterations. The way to spot it is that the trace fails on the last line and not inside the function.

If your only returning one variable from a function, I am not sure if the error would be produced... I suspect error "'NoneType' object is not iterable in Python" in this case is actually implying "Hey, I'm trying to iterate over the return values to assign them to these three variables in order but I'm only getting None to iterate over"

Select multiple images from android gallery

I got null from the Cursor. Then found a solution to convert the Uri into Bitmap that works perfectly.

Here is the solution that works for me:

@Override
public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
{

    if (resultCode == Activity.RESULT_OK) {

        if (requestCode == YOUR_REQUEST_CODE) {

            if (data != null) {

                if (data.getData() != null) {

                    Uri contentURI = data.getData();
                    ex_one.setImageURI(contentURI);

                    Log.d(TAG, "onActivityResult: " + contentURI.toString());
                    try {

                        Bitmap bitmap = MediaStore.Images.Media.getBitmap(context.getContentResolver(), contentURI);

                    } catch (IOException e) {
                        e.printStackTrace();
                    }

                } else {

                    if (data.getClipData() != null) {
                        ClipData mClipData = data.getClipData();
                        ArrayList<Uri> mArrayUri = new ArrayList<Uri>();
                        for (int i = 0; i < mClipData.getItemCount(); i++) {

                            ClipData.Item item = mClipData.getItemAt(i);
                            Uri uri = item.getUri();
                            try {
                                Bitmap bitmap = MediaStore.Images.Media.getBitmap(context.getContentResolver(), uri);
                            } catch (IOException e) {
                                e.printStackTrace();
                            }

                        }
                    }

                }

            }

        }

    }

}

NameError: global name is not defined

try

from sqlitedbx import SqliteDBzz

Query to count the number of tables I have in MySQL

Hope this helps, and returns only number of tables in a database

Use database;

SELECT COUNT(*) FROM sys.tables;

Git pull after forced update

This won't fix branches that already have the code you don't want in them (see below for how to do that), but if they had pulled some-branch and now want it to be clean (and not "ahead" of origin/some-branch) then you simply:

git checkout some-branch   # where some-branch can be replaced by any other branch
git branch base-branch -D  # where base-branch is the one with the squashed commits
git checkout -b base-branch origin/base-branch  # recreating branch with correct commits

Note: You can combine these all by putting && between them

Note2: Florian mentioned this in a comment, but who reads comments when looking for answers?

Note3: If you have contaminated branches, you can create new ones based off the new "dumb branch" and just cherry-pick commits over.

Ex:

git checkout feature-old  # some branch with the extra commits
git log                   # gives commits (write down the id of the ones you want)
git checkout base-branch  # after you have already cleaned your local copy of it as above
git checkout -b feature-new # make a new branch for your feature
git cherry-pick asdfasd   # where asdfasd is one of the commit ids you want
# repeat previous step for each commit id
git branch feature-old -D # delete the old branch

Now feature-new is your branch without the extra (possibly bad) commits!

Restore LogCat window within Android Studio

Try going to Tools->Android->Enable ADB Integration

In my case it got automagically disabled

Connect to Oracle DB using sqlplus

As David Aldridge explained, your parentheses should start right after the sqlplus command, so it should be:

sqlplus 'test/test@(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=hostname.com )(PORT=1521)))(CONNECT_DATA=(SID=mysid))'

How to run a cron job inside a docker container?

Define the cronjob in a dedicated container which runs the command via docker exec to your service.

This is higher cohesion and the running script will have access to the environment variables you have defined for your service.

#docker-compose.yml
version: "3.3"
services:
    myservice:
      environment:
        MSG: i'm being cronjobbed, every minute!
      image: alpine
      container_name: myservice
      command: tail -f /dev/null

    cronjobber:
     image: docker:edge
     volumes:
      - /var/run/docker.sock:/var/run/docker.sock
     container_name: cronjobber
     command: >
          sh -c "
          echo '* * * * * docker exec myservice printenv | grep MSG' > /etc/crontabs/root
          && crond -f"

GitLab git user password

In my case, I was using a pair of keys that didn't have the default names id_rsa and id_rsa.pub.

Producing keys with these names solved the problem, and I actually found it looking at the output of ssh -vT my_gitlab_address. Strange fact: it worked on one computer with Ubuntu, but not on others with different distributions and older versions of OpenSSH.

Wordpress keeps redirecting to install-php after migration

It seems that in general, this happens when Wordpress doesn't find the site information in the expected places (tables) in the database. It thinks no site has been created yet, so it starts going through the installation process.

This situation means that:

  1. Wordpress WAS ABLE to connect to a database. If it didn't, it would say there was an error and refuse to install or do anything else

AND

  1. it didn't find the things it was looking for in the expected places in the database it connected to.

Just to be clear, both 1) and 2) are happening when you see this symptom.

Possible causes:

  • Wrong database. You're working on several projects and you copied and pasted wrong database name, database host, or table prefix to the wp-config file. So now, you're unwittingly destroying ANOTHER client's website while agonizing over why isn't THIS website working at all.

  • Wrong database prefix. You can put several Wordpress sites in one database by using different prefixes for each. Make sure the tables in the database have the same prefixes as you entered in your wp-config. So, if wp-config says: $table_prefix = 'wp_'; Check that the tables in your database are called "wp_options", etc. and not "WP_options", "mysite_options" or something like that.

  • The data in the database is corrupted. Maybe you messed up while importing the sql dump, you imported a truncated file, a file belonging to some other project, or whatever.

phpMyAdmin + CentOS 6.0 - Forbidden

I tried all answers provided here: editing phpMyAdmin.conf, changing selinux context for phpmyadmin folder, disabling selinux... but I still got a 'Forbidden' from the web server.

I finally found what I was missing in Edouard Thiel post here :

$ yum install php

then restart httpd :

$ service httpd restart => for centos 6 hots

$ systemctl restart httpd => for centos 7 hosts

What has me amazed is why php is not installed as dependency for phpmyadmin in the first place.

Regards, Fred

.gitignore all the .DS_Store files in every folder and subfolder

  1. $ git rm ./*.DS_Store - remove all .DS_Store from git
  2. $ echo \.DS_Store >> .gitignore - ignore .DS_Store in future

commit & push

Include in SELECT a column that isn't actually in the database

You may want to use:

SELECT Name, 'Unpaid' AS Status FROM table;

The SELECT clause syntax, as defined in MSDN: SELECT Clause (Transact-SQL), is as follows:

SELECT [ ALL | DISTINCT ]
[ TOP ( expression ) [ PERCENT ] [ WITH TIES ] ] 
<select_list> 

Where the expression can be a constant, function, any combination of column names, constants, and functions connected by an operator or operators, or a subquery.

Set custom attribute using JavaScript

For people coming from Google, this question is not about data attributes - OP added a non-standard attribute to their HTML object, and wondered how to set it.

However, you should not add custom attributes to your properties - you should use data attributes - e.g. OP should have used data-icon, data-url, data-target, etc.

In any event, it turns out that the way you set these attributes via JavaScript is the same for both cases. Use:

ele.setAttribute(attributeName, value);

to change the given attribute attributeName to value for the DOM element ele.

For example:

document.getElementById("someElement").setAttribute("data-id", 2);

Note that you can also use .dataset to set the values of data attributes, but as @racemic points out, it is 62% slower (at least in Chrome on macOS at the time of writing). So I would recommend using the setAttribute method instead.

What does this thread join code mean?

When thread tA call tB.join() its causes not only waits for tB to die or tA be interrupted itself but create happens-before relation between last statement in tB and next statement after tB.join() in tA thread.

All actions in a thread happen-before any other thread successfully returns from a join() on that thread.

It means program

class App {
    // shared, not synchronized variable = bad practice
    static int sharedVar = 0;
    public static void main(String[] args) throws Exception {
        Thread threadB = new Thread(() -> {sharedVar = 1;});
        threadB.start();
        threadB.join();

        while (true) 
            System.out.print(sharedVar);
    }
}

Always print

>> 1111111111111111111111111 ...

But program

class App {
    // shared, not synchronized variable = bad practice
    static int sharedVar = 0;
    public static void main(String[] args) throws Exception {
        Thread threadB = new Thread(() -> {sharedVar = 1;});
        threadB.start();
        // threadB.join();  COMMENT JOIN

        while (true)
            System.out.print(sharedVar);
    }
}

Can print not only

>> 0000000000 ... 000000111111111111111111111111 ...

But

>> 00000000000000000000000000000000000000000000 ... 

Always only '0'.

Because Java Memory Model don't require 'transfering' new value of 'sharedVar' from threadB to main thread without heppens-before relation (thread start, thread join, usage of 'synchonized' keyword, usage of AtomicXXX variables, etc).

How do I find the maximum of 2 numbers?

numberList=[16,19,42,43,74,66]

largest = numberList[0]

for num2 in numberList:

    if num2 > largest:

        largest=num2

print(largest)

gives largest number out of the numberslist without using a Max statement

Object cannot be cast from DBNull to other types

I'm thinking that your output parameter is coming back with a DBNull value. Add a check for that like this

var outputParam = dataAccCom.GetParameterValue(IDbCmd, "op_Id");
if(!(outputParam is DBNull))
     DataTO.Id = Convert.ToInt64(outputParam);

Using "label for" on radio buttons

You almost got it. It should be this:

_x000D_
_x000D_
<input type="radio" name="group1" id="r1" value="1" />_x000D_
<label for="r1"> button one</label>
_x000D_
_x000D_
_x000D_

The value in for should be the id of the element you are labeling.

Mipmap drawables for icons

The Android implementation of mipmaps in 4.3 is exactly the technique from 1983 explained in the Wikipedia article :)

Each bitmap image of the mipmap set is a downsized duplicate of the main texture, but at a certain reduced level of detail. Although the main texture would still be used when the view is sufficient to render it in full detail, the renderer will switch to a suitable mipmap image (...) when the texture is viewed from a distance or at a small size.

Although this is described as a technique for 3D graphics (as it mentions "viewing from a distance"), it applies just as well to 2D (translated as "drawn is a smaller space", i.e. "downscaled").

For a concrete Android example, imagine you have a View with a certain background drawable (in particular, a BitmapDrawable). You now use an animation to scale it to 0.15 of its original size. Normally, this would require downscaling the background bitmap for each frame. This "extreme" downscaling, however, may produce visual artifacts.

You can, however, provide a mipmap, which means that the image is already pre-rendered for a few specific scales (let's say 1.0, 0.5, and 0.25). Whenever the animation "crosses" the 0.5 threshold, instead of continuing to downscale the original, 1.0-sized image, it will switch to the 0.5 image and downscale it, which should provide a better result. And so forth as the animation continues.

This is a bit theoretical, since it's actually done by the renderer. According to the source of the Bitmap class, it's just a hint, and the renderer may or may not honor it.

/**
 * Set a hint for the renderer responsible for drawing this bitmap
 * indicating that it should attempt to use mipmaps when this bitmap
 * is drawn scaled down.
 *
 * If you know that you are going to draw this bitmap at less than
 * 50% of its original size, you may be able to obtain a higher
 * quality by turning this property on.
 * 
 * Note that if the renderer respects this hint it might have to
 * allocate extra memory to hold the mipmap levels for this bitmap.
 *
 * This property is only a suggestion that can be ignored by the
 * renderer. It is not guaranteed to have any effect.
 *
 * @param hasMipMap indicates whether the renderer should attempt
 *                  to use mipmaps
 *
 * @see #hasMipMap()
 */
public final void setHasMipMap(boolean hasMipMap) {
    nativeSetHasMipMap(mNativeBitmap, hasMipMap);
}

I'm not quite sure why this would be especially suitable for application icons, though. Although Android on tablets, as well as some launchers (e.g. GEL), request an icon "one density higher" to show it bigger, this is supposed to be done using the regular mechanism (i.e. drawable-xxxhdpi, &c).

Short circuit Array.forEach like calling break

Use the array.prototype.every function, which provide you the utility to break the looping. See example here Javascript documentation on Mozilla developer network

How do I prompt for Yes/No/Cancel input in a Linux shell script?

more generic would be:

function menu(){
    title="Question time"
    prompt="Select:"
    options=("Yes" "No" "Maybe")
    echo "$title"
    PS3="$prompt"
    select opt in "${options[@]}" "Quit/Cancel"; do
        case "$REPLY" in
            1 ) echo "You picked $opt which is option $REPLY";;
            2 ) echo "You picked $opt which is option $REPLY";;
            3 ) echo "You picked $opt which is option $REPLY";;
            $(( ${#options[@]}+1 )) ) clear; echo "Goodbye!"; exit;;
            *) echo "Invalid option. Try another one.";continue;;
         esac
     done
     return
}

2D arrays in Python

If you want to do some serious work with arrays then you should use the numpy library. This will allow you for example to do vector addition and matrix multiplication, and for large arrays it is much faster than Python lists.

However, numpy requires that the size is predefined. Of course you can also store numpy arrays in a list, like:

import numpy as np
vec_list = [np.zeros((3,)) for _ in range(10)]
vec_list.append(np.array([1,2,3]))
vec_sum = vec_list[0] + vec_list[1]  # possible because we use numpy
print vec_list[10][2]  # prints 3

But since your numpy arrays are pretty small I guess there is some overhead compared to using a tuple. It all depends on your priorities.

See also this other question, which is pretty similar (apart from the variable size).

install cx_oracle for python

The following worked for me, both on mac and Linux. This one command should download needed additional files, without need need to set environment variables.

python -m pip install cx_Oracle --pre

Note, the --pre option is for development and pre-release of the Oracle driver. As of this posting, it was grabbing cx_Oracle-6.0rc1.tar.gz, which was needed. (I'm using python 3.6)

Getting HTTP code in PHP using curl

Here is my solution need get Status Http for checking status of server regularly

$url = 'http://www.example.com'; // Your server link

while(true) {

    $strHeader = get_headers($url)[0];

    $statusCode = substr($strHeader, 9, 3 );

    if($statusCode != 200 ) {
        echo 'Server down.';
        // Send email 
    }
    else {
        echo 'oK';
    }

    sleep(30);
}

Prevent jQuery UI dialog from setting focus to first textbox

Here is the solution I implemented after reading through jQuery UI ticket #4731, originally posted by slolife as a response to another answer. (The ticket was also created by him.)

First, in whatever method you use to apply autocompletes to the page, add the following line of code:

$.ui.dialog.prototype._focusTabbable = function(){};

That disables jQuery's "auto-focus" behavior. To ensure that your site continues to be broadly accessible, wrap your dialog creation methods so that additional code can be added, and add a call to focus the first input element:

function openDialog(context) {

    // Open your dialog here

    // Usability for screen readers.  Focus on an element so that screen readers report it.
    $("input:first", $(context)).focus();

}

To further address accessibility when autocomplete options are selected via keyboard, we override jQuery UI's "select" autocomplete callback and add some additional code to ensure the textElement does not lose focus in IE 8 after making a selection.

Here is the code we use to apply autocompletes to elements:

$.fn.applyAutocomplete = function () {

    // Prevents jQuery dialog from auto-focusing on the first tabbable element.
    // Make sure to wrap your dialog opens and focus on the first input element
    // for screen readers.
    $.ui.dialog.prototype._focusTabbable = function () { };

    $(".autocomplete", this)
        .each(function (index) {

            var textElement = this;

            var onSelect = $(this).autocomplete("option", "select");
            $(this).autocomplete("option", {
                select: function (event, ui) {
                    // Call the original functionality first
                    onSelect(event, ui);

                    // We replace a lot of content via AJAX in our project.
                    // This ensures proper copying of values if the original element which jQuery UI pointed to
                    // is replaced.
                    var $hiddenValueElement = $("#" + $(textElement).attr('data-jqui-acomp-hiddenvalue'));
                    if ($hiddenValueElement.attr("value") != ui.item.value) {
                        $hiddenValueElement.attr("value", ui.item.value);
                    }

                    // Replace text element value with that indicated by "display" if any
                    if (ui.item.display)
                        textElement.value = ui.item.display;

                    // For usability purposes.  When using the keyboard to select from an autocomplete, this returns focus to the textElement.
                    $(textElement).focus();

                    if (ui.item.display)
                        return false;

                }
            });
        })
        // Set/clear data flag that can be checked, if necessary, to determine whether list is currently dropped down
        .on("autocompleteopen", function (event, ui) {
            $(event.target).data().autocompleteIsDroppedDown = true;
        })
        .on("autocompleteclose", function (event, ui) {
            $(event.target).data().autocompleteIsDroppedDown = false;
        });

    return this;
}

How to clear or stop timeInterval in angularjs?

var interval = $interval(function() {
  console.log('say hello');
}, 1000);

$interval.cancel(interval);

How to set focus to a button widget programmatically?

Try this:

btn.requestFocusFromTouch();

Change the icon of the exe file generated from Visual Studio 2010

I found it easier to edit the project file directly e.g. YourApp.csproj.

You can do this by modifying ApplicationIcon property element:

<ApplicationIcon>..\Path\To\Application.ico</ApplicationIcon>

Also, if you create an MSI installer for your application e.g. using WiX, you can use the same icon again for display in Add/Remove Programs. See tip 5 here.

How Big can a Python List Get?

It varies for different systems (depends on RAM). The easiest way to find out is

import six six.MAXSIZE 9223372036854775807 This gives the max size of list and dict too ,as per the documentation

Angular2 disable button

If you are using reactive forms and want to disable some input associated with a form control, you should place this disabled logic into you code and call yourFormControl.disable() or yourFormControl.enable()

Case insensitive regular expression without re.compile?

Pass re.IGNORECASE to the flags param of search, match, or sub:

re.search('test', 'TeSt', re.IGNORECASE)
re.match('test', 'TeSt', re.IGNORECASE)
re.sub('test', 'xxxx', 'Testing', flags=re.IGNORECASE)

How to skip to next iteration in jQuery.each() util?

Javascript sort of has the idea of 'truthiness' and 'falsiness'. If a variable has a value then, generally 9as you will see) it has 'truthiness' - null, or no value tends to 'falsiness'. The snippets below might help:

var temp1; 
if ( temp1 )...  // false

var temp2 = true;
if ( temp2 )...  // true

var temp3 = "";
if ( temp3 ).... // false

var temp4 = "hello world";
if ( temp4 )...  // true

Hopefully that helps?

Also, its worth checking out these videos from Douglas Crockford

update: thanks @cphpython for spotting the broken links - I've updated to point at working versions now

The Javascript language

Javascript - The Good Parts

How to connect android emulator to the internet

  1. righ click on the Project in Eclipse
  2. select Run As -> Run Configurations ...
  3. select Android Application and then select "target" tab
  4. Looking for "Additional Emulator Command Line Options" and put this command line to text box

    -http-proxy http://< username >:< password >@< hostname >:< port >

How does setTimeout work in Node.JS?

The idea of non-blocking is that the loop iterations are quick. So to iterate for each tick should take short enough a time that the setTimeout will be accurate to within reasonable precision (off by maybe <100 ms or so).

In theory though you're right. If I write an application and block the tick, then setTimeouts will be delayed. So to answer you're question, who can assure setTimeouts execute on time? You, by writing non-blocking code, can control the degree of accuracy up to almost any reasonable degree of accuracy.

As long as javascript is "single-threaded" in terms of code execution (excluding web-workers and the like), that will always happen. The single-threaded nature is a huge simplification in most cases, but requires the non-blocking idiom to be successful.

Try this code out either in your browser or in node, and you'll see that there is no guarantee of accuracy, on the contrary, the setTimeout will be very late:

var start = Date.now();

// expecting something close to 500
setTimeout(function(){ console.log(Date.now() - start); }, 500);

// fiddle with the number of iterations depending on how quick your machine is
for(var i=0; i<5000000; ++i){}

Unless the interpreter optimises the loop away (which it doesn't on chrome), you'll get something in the thousands. Remove the loop and you'll see it's 500 on the nose...

Efficient way to rotate a list in python

I don't know if this is 'efficient', but it also works:

x = [1,2,3,4]
x.insert(0,x.pop())

EDIT: Hello again, I just found a big problem with this solution! Consider the following code:

class MyClass():
    def __init__(self):
        self.classlist = []

    def shift_classlist(self): # right-shift-operation
        self.classlist.insert(0, self.classlist.pop())

if __name__ == '__main__':
    otherlist = [1,2,3]
    x = MyClass()

    # this is where kind of a magic link is created...
    x.classlist = otherlist

    for ii in xrange(2): # just to do it 2 times
        print '\n\n\nbefore shift:'
        print '     x.classlist =', x.classlist
        print '     otherlist =', otherlist
        x.shift_classlist() 
        print 'after shift:'
        print '     x.classlist =', x.classlist
        print '     otherlist =', otherlist, '<-- SHOULD NOT HAVE BIN CHANGED!'

The shift_classlist() method executes the same code as my x.insert(0,x.pop())-solution, otherlist is a list indipendent from the class. After passing the content of otherlist to the MyClass.classlist list, calling the shift_classlist() also changes the otherlist list:

CONSOLE OUTPUT:

before shift:
     x.classlist = [1, 2, 3]
     otherlist = [1, 2, 3]
after shift:
     x.classlist = [3, 1, 2]
     otherlist = [3, 1, 2] <-- SHOULD NOT HAVE BIN CHANGED!



before shift:
     x.classlist = [3, 1, 2]
     otherlist = [3, 1, 2]
after shift:
     x.classlist = [2, 3, 1]
     otherlist = [2, 3, 1] <-- SHOULD NOT HAVE BIN CHANGED!

I use Python 2.7. I don't know if thats a bug, but I think it's more likely that I missunderstood something here.

Does anyone of you know why this happens?

jQuery select change event get selected option

You can use the jQuery find method

 $('select').change(function () {
     var optionSelected = $(this).find("option:selected");
     var valueSelected  = optionSelected.val();
     var textSelected   = optionSelected.text();
 });

The above solution works perfectly but I choose to add the following code for them willing to get the clicked option. It allows you get the selected option even when this select value has not changed. (Tested with Mozilla only)

    $('select').find('option').click(function () {
     var optionSelected = $(this);
     var valueSelected  = optionSelected.val();
     var textSelected   = optionSelected.text();
   });

CAST to DECIMAL in MySQL

An alternative, I think for your purpose, is to use the round() function:

select round((10 * 1.5),2) // prints 15.00

You can try it here:

How do I perform a JAVA callback between classes?

I don't know if this is what you are looking for, but you can achieve this by passing a callback to the child class.

first define a generic callback:

public interface ITypedCallback<T> {
    void execute(T type);
}

create a new ITypedCallback instance on ServerConnections instantiation:

public Server(int _address) {
    serverConnectionHandler = new ServerConnections(new ITypedCallback<Socket>() {
        @Override
        public void execute(Socket socket) {
            // do something with your socket here
        }
    });
}

call the execute methode on the callback object.

public class ServerConnections implements Runnable {

    private ITypedCallback<Socket> callback;

    public ServerConnections(ITypedCallback<Socket> _callback) {
        callback = _callback;
    }

    @Override
    public void run() {   
        try {
            mainSocket = new ServerSocket(serverPort);
            while (true) {
                callback.execute(mainSocket.accept());
            }
        } catch (IOException ex) {
            Logger.getLogger(Server.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

btw: I didn't check if it's 100% correct, directly coded it here.

Show DialogFragment with animation growing from a point

To get a full-screen dialog with animation, write the following ...

Styles:

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
    <item name="actionModeBackground">?attr/colorPrimary</item>
    <item name="windowActionModeOverlay">true</item>
</style>

<style name="AppTheme.NoActionBar">
    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>
</style>

<style name="AppTheme.NoActionBar.FullScreenDialog">
    <item name="android:windowAnimationStyle">@style/Animation.WindowSlideUpDown</item>
</style>

<style name="Animation.WindowSlideUpDown" parent="@android:style/Animation.Activity">
    <item name="android:windowEnterAnimation">@anim/slide_up</item>
    <item name="android:windowExitAnimation">@anim/slide_down</item>
</style>

res/anim/slide_up.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
     android:shareInterpolator="@android:interpolator/accelerate_quad">

    <translate
        android:duration="@android:integer/config_shortAnimTime"
        android:fromYDelta="100%"
        android:toYDelta="0%"/>
</set>

res/anim/slide_down.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
     android:shareInterpolator="@android:interpolator/accelerate_quad">

    <translate
        android:duration="@android:integer/config_shortAnimTime"
        android:fromYDelta="0%"
        android:toYDelta="100%"/>
</set>

Java code:

public class MyDialog extends DialogFragment {

    @Override
    public int getTheme() {
        return R.style.AppTheme_NoActionBar_FullScreenDialog;
    }
}

private void showDialog() {
    FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
    Fragment previous = getSupportFragmentManager().findFragmentByTag(MyDialog.class.getName());
    if (previous != null) {
        fragmentTransaction.remove(previous);
    }
    fragmentTransaction.addToBackStack(null);

    MyDialog dialog = new MyDialog();
    dialog.show(fragmentTransaction, MyDialog.class.getName());
}

How can I edit a .jar file?

A jar file is a zip archive. You can extract it using 7zip (a great simple tool to open archives). You can also change its extension to zip and use whatever to unzip the file.

Now you have your class file. There is no easy way to edit class file, because class files are binaries (you won't find source code in there. maybe some strings, but not java code). To edit your class file you can use a tool like classeditor.

You have all the strings your class is using hard-coded in the class file. So if the only thing you would like to change is some strings you can do it without using classeditor.

Read all worksheets in an Excel workbook into an R list with data.frames

excel.link will do the job.

I actually found it easier to use compared to XLConnect (not that either package is that difficult to use). Learning curve for both was about 5 minutes.

As an aside, you can easily find all R packages that mention the word "Excel" by browsing to http://cran.r-project.org/web/packages/available_packages_by_name.html

How to convert std::chrono::time_point to calendar datetime string with fractional seconds?

I would have put this in a comment on the accepted answer, since that's where it belongs, but I can't. So, just in case anyone gets unreliable results, this could be why.

Be careful of the accepted answer, it fails if the time_point is before the epoch.

This line of code:

std::size_t fractional_seconds = ms.count() % 1000;

will yield unexpected values if ms.count() is negative (since size_t is not meant to hold negative values).

UIAlertView first deprecated IOS 9

From iOS8 Apple provide new UIAlertController class which you can use instead of UIAlertView which is now deprecated, it is also stated in deprecation message:

UIAlertView is deprecated. Use UIAlertController with a preferredStyle of UIAlertControllerStyleAlert instead

So you should use something like this

UIAlertController * alert = [UIAlertController
                alertControllerWithTitle:@"Title"
                                 message:@"Message"
                          preferredStyle:UIAlertControllerStyleAlert];



UIAlertAction* yesButton = [UIAlertAction
                    actionWithTitle:@"Yes, please"
                              style:UIAlertActionStyleDefault
                            handler:^(UIAlertAction * action) {
                                //Handle your yes please button action here
                            }];

UIAlertAction* noButton = [UIAlertAction
                        actionWithTitle:@"No, thanks"
                                  style:UIAlertActionStyleDefault
                                handler:^(UIAlertAction * action) {
                                   //Handle no, thanks button                
                                }];

[alert addAction:yesButton];
[alert addAction:noButton];

[self presentViewController:alert animated:YES completion:nil];

Check if number is prime number

I think this is the easiest way to do it.

static bool IsPrime(int number)
{
   for (int i = 2; i <= number/2; i++)
       if (number % i == 0)
           return false;
    return true;
}

How to create checkbox inside dropdown?

Here is a simple dropdown checklist:

_x000D_
_x000D_
var checkList = document.getElementById('list1');
checkList.getElementsByClassName('anchor')[0].onclick = function(evt) {
  if (checkList.classList.contains('visible'))
    checkList.classList.remove('visible');
  else
    checkList.classList.add('visible');
}
_x000D_
.dropdown-check-list {
  display: inline-block;
}

.dropdown-check-list .anchor {
  position: relative;
  cursor: pointer;
  display: inline-block;
  padding: 5px 50px 5px 10px;
  border: 1px solid #ccc;
}

.dropdown-check-list .anchor:after {
  position: absolute;
  content: "";
  border-left: 2px solid black;
  border-top: 2px solid black;
  padding: 5px;
  right: 10px;
  top: 20%;
  -moz-transform: rotate(-135deg);
  -ms-transform: rotate(-135deg);
  -o-transform: rotate(-135deg);
  -webkit-transform: rotate(-135deg);
  transform: rotate(-135deg);
}

.dropdown-check-list .anchor:active:after {
  right: 8px;
  top: 21%;
}

.dropdown-check-list ul.items {
  padding: 2px;
  display: none;
  margin: 0;
  border: 1px solid #ccc;
  border-top: none;
}

.dropdown-check-list ul.items li {
  list-style: none;
}

.dropdown-check-list.visible .anchor {
  color: #0094ff;
}

.dropdown-check-list.visible .items {
  display: block;
}
_x000D_
<div id="list1" class="dropdown-check-list" tabindex="100">
  <span class="anchor">Select Fruits</span>
  <ul class="items">
    <li><input type="checkbox" />Apple </li>
    <li><input type="checkbox" />Orange</li>
    <li><input type="checkbox" />Grapes </li>
    <li><input type="checkbox" />Berry </li>
    <li><input type="checkbox" />Mango </li>
    <li><input type="checkbox" />Banana </li>
    <li><input type="checkbox" />Tomato</li>
  </ul>
</div>
_x000D_
_x000D_
_x000D_

Min/Max-value validators in asp.net mvc

jQuery Validation Plugin already implements min and max rules, we just need to create an adapter for our custom attribute:

public class MaxAttribute : ValidationAttribute, IClientValidatable
{
    private readonly int maxValue;

    public MaxAttribute(int maxValue)
    {
        this.maxValue = maxValue;
    }

    public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
    {
        var rule = new ModelClientValidationRule();

        rule.ErrorMessage = ErrorMessageString, maxValue;

        rule.ValidationType = "max";
        rule.ValidationParameters.Add("max", maxValue);
        yield return rule;
    }

    public override bool IsValid(object value)
    {
        return (int)value <= maxValue;
    }
}

Adapter:

$.validator.unobtrusive.adapters.add(
   'max',
   ['max'],
   function (options) {
       options.rules['max'] = parseInt(options.params['max'], 10);
       options.messages['max'] = options.message;
   });

Min attribute would be very similar.

CSS class for pointer cursor

UPDATE for Bootstrap 4 stable

The cursor: pointer; rule has been restored, so buttons will now by default have the cursor on hover:

_x000D_
_x000D_
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css">_x000D_
<button type="button" class="btn btn-success">Sample Button</button>
_x000D_
_x000D_
_x000D_


No, there isn't. You need to make some custom CSS for this.

If you just need a link that looks like a button (with pointer), use this:

_x000D_
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<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css">_x000D_
<a class="btn btn-success" href="#" role="button">Sample Button</a>
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In PHP, what is a closure and why does it use the "use" identifier?

A simpler answer.

function ($quantity) use ($tax, &$total) { .. };

  1. The closure is a function assigned to a variable, so you can pass it around
  2. A closure is a separate namespace, normally, you can not access variables defined outside of this namespace. There comes the use keyword:
  3. use allows you to access (use) the succeeding variables inside the closure.
  4. use is early binding. That means the variable values are COPIED upon DEFINING the closure. So modifying $tax inside the closure has no external effect, unless it is a pointer, like an object is.
  5. You can pass in variables as pointers like in case of &$total. This way, modifying the value of $total DOES HAVE an external effect, the original variable's value changes.
  6. Variables defined inside the closure are not accessible from outside the closure either.
  7. Closures and functions have the same speed. Yes, you can use them all over your scripts.

As @Mytskine pointed out probably the best in-depth explanation is the RFC for closures. (Upvote him for this.)

Can dplyr join on multiple columns or composite key?

Updating to use tibble()

You can pass a named vector of length greater than 1 to the by argument of left_join():

library(dplyr)

d1 <- tibble(
  x = letters[1:3],
  y = LETTERS[1:3],
  a = rnorm(3)
  )

d2 <- tibble(
  x2 = letters[3:1],
  y2 = LETTERS[3:1],
  b = rnorm(3)
  )

left_join(d1, d2, by = c("x" = "x2", "y" = "y2"))

json Uncaught SyntaxError: Unexpected token :

You've told jQuery to expect a JSONP response, which is why jQuery has added the callback=jQuery16406345664265099913_1319854793396&_=1319854793399 part to the URL (you can see this in your dump of the request).

What you're returning is JSON, not JSONP. Your response looks like

{"red" : "#f00"}

and jQuery is expecting something like this:

jQuery16406345664265099913_1319854793396({"red" : "#f00"})

If you actually need to use JSONP to get around the same origin policy, then the server serving colors.json needs to be able to actually return a JSONP response.

If the same origin policy isn't an issue for your application, then you just need to fix the dataType in your jQuery.ajax call to be json instead of jsonp.

Android app unable to start activity componentinfo

Your null pointer exception seems to be on this line:

String url = intent.getExtras().getString("userurl");

because intent.getExtras() returns null when the intent doesn't have any extras.

You have to realize that this piece of code:

Intent Main = new Intent(this, ToClass.class);
Main.putExtra("userurl", url);
startActivity(Main);

doesn't start the activity you wrote in Main.java, it will attempt to start an activity called ToClass and if that doesn't exist, your app crashes.

Also, there is no such thing as "android.intent.action.start" so the manifest should look more like:

<activity android:name=".start" android:label="@string/app_name">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>
<activity android:name= ".Main">
</activity>

I hope this fixes some of the issues you are encountering but I strongly suggest you check out some "getting started" tutorials for android development and build up from there.

How to resize a VirtualBox vmdk file

Actually, Only this these commands are needed:

VBoxManage clonehd "source.vmdk" "cloned.vdi" --format vdi
VBoxManage modifyhd "cloned.vdi" --resize 51200

Then, you can select cloned.dvi in Virtualbox GUI storage.

After that, start the virtual windows and expand your C disk as the methods of Code Chops.

It is not necessary to convert the *.vdi file to *.vmdk file back.

How to use a global array in C#?

Your class shoud look something like this:

class Something {     int[] array; //global array, replace type of course     void function1() {        array = new int[10]; //let say you declare it here that will be 10 integers in size     }     void function2() {        array[0] = 12; //assing value at index 0 to 12.     } } 

That way you array will be accessible in both functions. However, you must be careful with global stuff, as you can quickly overwrite something.

How can I edit a view using phpMyAdmin 3.2.4?

Just export you view and you will have all SQL need to make some change on it.

Just need to add your change in SQL query for the view and change :

CREATE for CREATE OR REPLACE

JAXB: how to marshall map into <key>value</key>

I found easiest solution.

@XmlElement(name="attribute")
    public String[] getAttributes(){
        return attributes.keySet().toArray(new String[1]);
    }
}

Now it will generate in you xml output like this:

<attribute>key1<attribute>
...
<attribute>keyN<attribute>

how to create a logfile in php?

create a logfile in php, to do it you need to pass data on function and it will create log file for you.

function wh_log($log_msg)
{
    $log_filename = "log";
    if (!file_exists($log_filename)) 
    {
        // create directory/folder uploads.
        mkdir($log_filename, 0777, true);
    }
    $log_file_data = $log_filename.'/log_' . date('d-M-Y') . '.log';
    // if you don't add `FILE_APPEND`, the file will be erased each time you add a log
    file_put_contents($log_file_data, $log_msg . "\n", FILE_APPEND);
} 
// call to function
wh_log("this is my log message");

How do I join two lists in Java?

A little shorter would be:

List<String> newList = new ArrayList<String>(listOne);
newList.addAll(listTwo);

Find oldest/youngest datetime object in a list

Datetimes are comparable; so you can use max(datetimes_list) and min(datetimes_list)

Error ITMS-90717: "Invalid App Store Icon"

If you don't have a mac, on windows you can open Paint and save as PNG with correct dimensions 1024x1024

Where does Jenkins store configuration files for the jobs it runs?

On Linux one can find the home directory of Jenkins looking for a file, that Jenkins' home contains, e.g.:

$ find / -name "config.xml" | grep "jenkins"
/var/lib/jenkins/config.xml

Using a SELECT statement within a WHERE clause

Subquery is the name.

At times it's required, but good/bad depends on how it's applied.

Namenode not getting started

If your namenode is stuck in safemode you can ssh to namenode, su hdfs user and run the following command to turn off safemode:

hdfs dfsadmin -fs hdfs://server.com:8020 -safemode leave

What is a mutex?

A Mutex is a mutually exclusive flag. It acts as a gate keeper to a section of code allowing one thread in and blocking access to all others. This ensures that the code being controled will only be hit by a single thread at a time. Just be sure to release the mutex when you are done. :)

Setting HttpContext.Current.Session in a unit test

Try this:

        // MockHttpSession Setup
        var session = new MockHttpSession();

        // MockHttpRequest Setup - mock AJAX request
        var httpRequest = new Mock<HttpRequestBase>();

        // Setup this part of the HTTP request for AJAX calls
        httpRequest.Setup(req => req["X-Requested-With"]).Returns("XMLHttpRequest");

        // MockHttpContextBase Setup - mock request, cache, and session
        var httpContext = new Mock<HttpContextBase>();
        httpContext.Setup(ctx => ctx.Request).Returns(httpRequest.Object);
        httpContext.Setup(ctx => ctx.Cache).Returns(HttpRuntime.Cache);
        httpContext.Setup(ctx => ctx.Session).Returns(session);

        // MockHttpContext for cache
        var contextRequest = new HttpRequest("", "http://localhost/", "");
        var contextResponse = new HttpResponse(new StringWriter());
        HttpContext.Current = new HttpContext(contextRequest, contextResponse);

        // MockControllerContext Setup
        var context = new Mock<ControllerContext>();
        context.Setup(ctx => ctx.HttpContext).Returns(httpContext.Object);

        //TODO: Create new controller here
        //      Set controller's ControllerContext to context.Object

And Add the class:

public class MockHttpSession : HttpSessionStateBase
{
    Dictionary<string, object> _sessionDictionary = new Dictionary<string, object>();
    public override object this[string name]
    {
        get
        {
            return _sessionDictionary.ContainsKey(name) ? _sessionDictionary[name] : null;
        }
        set
        {
            _sessionDictionary[name] = value;
        }
    }

    public override void Abandon()
    {
        var keys = new List<string>();

        foreach (var kvp in _sessionDictionary)
        {
            keys.Add(kvp.Key);
        }

        foreach (var key in keys)
        {
            _sessionDictionary.Remove(key);
        }
    }

    public override void Clear()
    {
        var keys = new List<string>();

        foreach (var kvp in _sessionDictionary)
        {
            keys.Add(kvp.Key);
        }

        foreach(var key in keys)
        {
            _sessionDictionary.Remove(key);
        }
    }
}

This will allow you to test with both session and cache.

How to calculate moving average without keeping the count and data-total?

New average = old average * (n-1)/n + new value /n

This is assuming the count only changed by one value. In case it is changed by M values then:

new average = old average * (n-len(M))/n + (sum of values in M)/n).

This is the mathematical formula (I believe the most efficient one), believe you can do further code by yourselves

How to extract file name from path?

The simplest approach if you are sure the file physically exists on the disk:

Dim fileName, filePath As String
filePath = "C:\Documents\myfile.pdf"
fileName = Dir(filePath)

If you are not sure about existence of file or just want to extract filename from a given path then, simplest approach is:

fileName = Mid(filePath, InStrRev(filePath, "\") + 1)

MaxJsonLength exception in ASP.NET MVC during JavaScriptSerializer

If use Json.NET to generate the json string, it doesn't need to set MaxJsonLength value.

return new ContentResult()
{
    Content = Newtonsoft.Json.JsonConvert.SerializeObject(data),
    ContentType = "application/json",
};

How do I hide the status bar in a Swift iOS app?

  1. Go to Info.plist file
  2. Hover on one of those lines and a (+) and (-) button will show up.
  3. Click the plus button to add new key Type in start with capital V and automatically the first choice will be View controller-based status bar appearance.
  4. Add that as the KEY.
  5. Set the VALUE to "NO"
  6. Go to you AppDelegate.swift
  7. Add the code, inside the method

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject:AnyObject]?) -> Bool {
        application.statusBarHidden = true
        return true
    }
    

DONE! Run your app and no more status bar!

Cannot open output file, permission denied

I had the same Problem. Just rename your .CPP file to other name and try it again. It worked for me.

How to detect tableView cell touched or clicked in swift

 # Check delegate? first must be connected owner of view controller

    # Simple implementation of the didSelectRowAt function.

    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
         print("row selection: \(indexPath.row)")
    }

Is there a Python equivalent of the C# null-coalescing operator?

other = s or "some default value"

Ok, it must be clarified how the or operator works. It is a boolean operator, so it works in a boolean context. If the values are not boolean, they are converted to boolean for the purposes of the operator.

Note that the or operator does not return only True or False. Instead, it returns the first operand if the first operand evaluates to true, and it returns the second operand if the first operand evaluates to false.

In this case, the expression x or y returns x if it is True or evaluates to true when converted to boolean. Otherwise, it returns y. For most cases, this will serve for the very same purpose of C?'s null-coalescing operator, but keep in mind:

42    or "something"    # returns 42
0     or "something"    # returns "something"
None  or "something"    # returns "something"
False or "something"    # returns "something"
""    or "something"    # returns "something"

If you use your variable s to hold something that is either a reference to the instance of a class or None (as long as your class does not define members __nonzero__() and __len__()), it is secure to use the same semantics as the null-coalescing operator.

In fact, it may even be useful to have this side-effect of Python. Since you know what values evaluates to false, you can use this to trigger the default value without using None specifically (an error object, for example).

In some languages this behavior is referred to as the Elvis operator.

Putting GridView data in a DataTable

Copying Grid to datatable

        if (GridView.Rows.Count != 0)
        {
            //Forloop for header
            for (int i = 0; i < GridView.HeaderRow.Cells.Count; i++)
            {
                dt.Columns.Add(GridView.HeaderRow.Cells[i].Text);
            }
            //foreach for datarow
            foreach (GridViewRow row in GridView.Rows)
            {
                DataRow dr = dt.NewRow();
                for (int j = 0; j < row.Cells.Count; j++)
                {
                    dr[GridView.HeaderRow.Cells[j].Text] = row.Cells[j].Text;
                }
                dt.Rows.Add(dr);
            }
            //Loop for footer
            if (GridView.FooterRow.Cells.Count != 0)
            {
                DataRow dr = dt.NewRow();
                for (int i = 0; i < GridView.FooterRow.Cells.Count; i++)
                {
                    //You have to re-do the work if you did anything in databound for footer.  
                }
                dt.Rows.Add(dr);
            }
            dt.TableName = "tb";
        }

invalid_grant trying to get oAuth token from google

I encountered the same problem. For me, I fixed this by using Email Address (the string that ends with [email protected]) instead of Client ID for client_id parameter value. The naming set by Google is confusing here.

What is the difference between join and merge in Pandas?

One of the difference is that merge is creating a new index, and join is keeping the left side index. It can have a big consequence on your later transformations if you wrongly assume that your index isn't changed with merge.

For example:

import pandas as pd

df1 = pd.DataFrame({'org_index': [101, 102, 103, 104],
                    'date': [201801, 201801, 201802, 201802],
                    'val': [1, 2, 3, 4]}, index=[101, 102, 103, 104])
df1

       date  org_index  val
101  201801        101    1
102  201801        102    2
103  201802        103    3
104  201802        104    4

-

df2 = pd.DataFrame({'date': [201801, 201802], 'dateval': ['A', 'B']}).set_index('date')
df2

       dateval
date          
201801       A
201802       B

-

df1.merge(df2, on='date')

     date  org_index  val dateval
0  201801        101    1       A
1  201801        102    2       A
2  201802        103    3       B
3  201802        104    4       B

-

df1.join(df2, on='date')
       date  org_index  val dateval
101  201801        101    1       A
102  201801        102    2       A
103  201802        103    3       B
104  201802        104    4       B

How can I use optional parameters in a T-SQL stored procedure?

The answer from @KM is good as far as it goes but fails to fully follow up on one of his early bits of advice;

..., ignore compact code, ignore worrying about repeating code, ...

If you are looking to achieve the best performance then you should write a bespoke query for each possible combination of optional criteria. This might sound extreme, and if you have a lot of optional criteria then it might be, but performance is often a trade-off between effort and results. In practice, there might be a common set of parameter combinations that can be targeted with bespoke queries, then a generic query (as per the other answers) for all other combinations.

CREATE PROCEDURE spDoSearch
    @FirstName varchar(25) = null,
    @LastName varchar(25) = null,
    @Title varchar(25) = null
AS
BEGIN

    IF (@FirstName IS NOT NULL AND @LastName IS NULL AND @Title IS NULL)
        -- Search by first name only
        SELECT ID, FirstName, LastName, Title
        FROM tblUsers
        WHERE
            FirstName = @FirstName

    ELSE IF (@FirstName IS NULL AND @LastName IS NOT NULL AND @Title IS NULL)
        -- Search by last name only
        SELECT ID, FirstName, LastName, Title
        FROM tblUsers
        WHERE
            LastName = @LastName

    ELSE IF (@FirstName IS NULL AND @LastName IS NULL AND @Title IS NOT NULL)
        -- Search by title only
        SELECT ID, FirstName, LastName, Title
        FROM tblUsers
        WHERE
            Title = @Title

    ELSE IF (@FirstName IS NOT NULL AND @LastName IS NOT NULL AND @Title IS NULL)
        -- Search by first and last name
        SELECT ID, FirstName, LastName, Title
        FROM tblUsers
        WHERE
            FirstName = @FirstName
            AND LastName = @LastName

    ELSE
        -- Search by any other combination
        SELECT ID, FirstName, LastName, Title
        FROM tblUsers
        WHERE
                (@FirstName IS NULL OR (FirstName = @FirstName))
            AND (@LastName  IS NULL OR (LastName  = @LastName ))
            AND (@Title     IS NULL OR (Title     = @Title    ))

END

The advantage of this approach is that in the common cases handled by bespoke queries the query is as efficient as it can be - there's no impact by the unsupplied criteria. Also, indexes and other performance enhancements can be targeted at specific bespoke queries rather than trying to satisfy all possible situations.

Generate random numbers using C++11 random library

My 'random' library provide a high convenient wrapper around C++11 random classes. You can do almost all things with a simple 'get' method.

Examples:

  1. Random number in a range

    auto val = Random::get(-10, 10); // Integer
    auto val = Random::get(10.f, -10.f); // Float point
    
  2. Random boolean

    auto val = Random::get<bool>( ) // 50% to generate true
    auto val = Random::get<bool>( 0.7 ) // 70% to generate true
    
  3. Random value from a std::initilizer_list

    auto val = Random::get( { 1, 3, 5, 7, 9 } ); // val = 1 or 3 or...
    
  4. Random iterator from iterator range or all container

    auto it = Random::get( vec.begin(), vec.end() ); // it = random iterator
    auto it = Random::get( vec ); // return random iterator
    

And even more things ! Check out the github page:

https://github.com/effolkronium/random

How can I get the SQL of a PreparedStatement?

I've extracted my sql from PreparedStatement using preparedStatement.toString() In my case toString() returns String like this:

org.hsqldb.jdbc.JDBCPreparedStatement@7098b907[sql=[INSERT INTO 
TABLE_NAME(COLUMN_NAME, COLUMN_NAME, COLUMN_NAME) VALUES(?, ?, ?)],
parameters=[[value], [value], [value]]]

Now I've created a method (Java 8), which is using regex to extract both query and values and put them into map:

private Map<String, String> extractSql(PreparedStatement preparedStatement) {
    Map<String, String> extractedParameters = new HashMap<>();
    Pattern pattern = Pattern.compile(".*\\[sql=\\[(.*)],\\sparameters=\\[(.*)]].*");
    Matcher matcher = pattern.matcher(preparedStatement.toString());
    while (matcher.find()) {
      extractedParameters.put("query", matcher.group(1));
      extractedParameters.put("values", Stream.of(matcher.group(2).split(","))
          .map(line -> line.replaceAll("(\\[|])", ""))
          .collect(Collectors.joining(", ")));
    }
    return extractedParameters;
  }

This method returns map where we have key-value pairs:

"query" -> "INSERT INTO TABLE_NAME(COLUMN_NAME, COLUMN_NAME, COLUMN_NAME) VALUES(?, ?, ?)"
"values" -> "value,  value,  value"

Now - if you want values as list you can just simply use:

List<String> values = Stream.of(yourExtractedParametersMap.get("values").split(","))
    .collect(Collectors.toList());

If your preparedStatement.toString() is different than in my case it's just a matter of "adjusting" regex.

Convert java.util.date default format to Timestamp in Java

You can use

  long startTime = date.getTime() * 1000000;;
  long estimatedTime = System.nanoTime() - startTime;

To get time in nano.

Java Docs

Get a pixel from HTML Canvas?

Fast and handy

Use following class which implement fast method described in this article and contains all you need: readPixel, putPixel, get width/height. Class update canvas after calling refresh() method. Example solve simple case of 2d wave equation

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class Screen{
  constructor(canvasSelector) {
    this.canvas = document.querySelector(canvasSelector);
    this.width  = this.canvas.width;
    this.height = this.canvas.height;
    this.ctx = this.canvas.getContext('2d');
    this.imageData = this.ctx.getImageData(0, 0, this.width, this.height);
    this.buf = new ArrayBuffer(this.imageData.data.length);
    this.buf8 = new Uint8ClampedArray(this.buf);
    this.data = new Uint32Array(this.buf);  
  }
  
  // r,g,b,a - red, gren, blue, alpha components in range 0-255
  putPixel(x,y,r,g,b,a=255) {
    this.data[y * this.width + x] = (a << 24) | (b << 16) | (g <<  8) | r;
  }
  
  readPixel(x,y) {
    let p= this.data[y * this.width + x]
    return [p&0xff, p>>8&0xff, p>>16&0xff, p>>>24];
  }

  refresh() {
    this.imageData.data.set(this.buf8);
    this.ctx.putImageData(this.imageData, 0, 0);
  }
}




// --------
// TEST
// --------

let s=new Screen('#canvas');

function draw() {

  for (var y = 1; y < s.height-1; ++y) {
    for (var x = 1; x < s.width-1; ++x) {      
      let a = [[1,0],[-1,0],[0,1],[0,-1]].reduce((a,[xp,yp])=> 
        a+= s.readPixel(x+xp,y+yp)[0]
      ,0);
      let v=a/2-tmp[x][y];
      tmp[x][y]=v<0 ? 0:v;
    }
  }

  for (var y = 1; y < s.height-1; ++y) {
    for (var x = 1; x < s.width-1; ++x) {  
      let v=tmp[x][y];
      tmp[x][y]= s.readPixel(x,y)[0];
      s.putPixel(x,y, v,v,v);
    }
  }

  s.refresh();
  window.requestAnimationFrame(draw)
}

// temporary 2d buffer ()for solving wave equation)
let tmp = [...Array(s.width)].map(x => Array(s.height).fill(0));

function move(e) { s.putPixel(e.x-10, e.y-10, 255,255,255);}

draw();
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<canvas id="canvas" height="150" width="512" onmousemove="move(event)"></canvas>
<div>Move mouse on black box</div>
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How can I replace non-printable Unicode characters in Java?

Op De Cirkel is mostly right. His suggestion will work in most cases:

myString.replaceAll("\\p{C}", "?");

But if myString might contain non-BMP codepoints then it's more complicated. \p{C} contains the surrogate codepoints of \p{Cs}. The replacement method above will corrupt non-BMP codepoints by sometimes replacing only half of the surrogate pair. It's possible this is a Java bug rather than intended behavior.

Using the other constituent categories is an option:

myString.replaceAll("[\\p{Cc}\\p{Cf}\\p{Co}\\p{Cn}]", "?");

However, solitary surrogate characters not part of a pair (each surrogate character has an assigned codepoint) will not be removed. A non-regex approach is the only way I know to properly handle \p{C}:

StringBuilder newString = new StringBuilder(myString.length());
for (int offset = 0; offset < myString.length();)
{
    int codePoint = myString.codePointAt(offset);
    offset += Character.charCount(codePoint);

    // Replace invisible control characters and unused code points
    switch (Character.getType(codePoint))
    {
        case Character.CONTROL:     // \p{Cc}
        case Character.FORMAT:      // \p{Cf}
        case Character.PRIVATE_USE: // \p{Co}
        case Character.SURROGATE:   // \p{Cs}
        case Character.UNASSIGNED:  // \p{Cn}
            newString.append('?');
            break;
        default:
            newString.append(Character.toChars(codePoint));
            break;
    }
}

jQuery form validation on button click

Within your click handler, the mistake is the .validate() method; it only initializes the plugin, it does not validate the form.

To eliminate the need to have a submit button within the form, use .valid() to trigger a validation check...

$('#btn').on('click', function() {
    $("#form1").valid();
});

jsFiddle Demo

.validate() - to initialize the plugin (with options) once on DOM ready.

.valid() - to check validation state (boolean value) or to trigger a validation test on the form at any time.

Otherwise, if you had a type="submit" button within the form container, you would not need a special click handler and the .valid() method, as the plugin would capture that automatically.

Demo without click handler


EDIT:

You also have two issues within your HTML...

<input id="field1" type="text" class="required">
  • You don't need class="required" when declaring rules within .validate(). It's redundant and superfluous.

  • The name attribute is missing. Rules are declared within .validate() by their name. The plugin depends upon unique name attributes to keep track of the inputs.

Should be...

<input name="field1" id="field1" type="text" />

How to update all MySQL table rows at the same time?

You can try this,

UPDATE *tableName* SET *field1* = *your_data*, *field2* = *your_data* ... WHERE 1 = 1;

Well in your case if you want to update your online_status to some value, you can try this,

UPDATE thisTable SET online_status = 'Online' WHERE 1 = 1;

Hope it helps. :D

Drop rows containing empty cells from a pandas DataFrame

You can use this variation:

import pandas as pd
vals = {
    'name' : ['n1', 'n2', 'n3', 'n4', 'n5', 'n6', 'n7'],
    'gender' : ['m', 'f', 'f', 'f',  'f', 'c', 'c'],
    'age' : [39, 12, 27, 13, 36, 29, 10],
    'education' : ['ma', None, 'school', None, 'ba', None, None]
}
df_vals = pd.DataFrame(vals) #converting dict to dataframe

This will output(** - highlighting only desired rows):

   age education gender name
0   39        ma      m   n1 **
1   12      None      f   n2    
2   27    school      f   n3 **
3   13      None      f   n4
4   36        ba      f   n5 **
5   29      None      c   n6
6   10      None      c   n7

So to drop everything that does not have an 'education' value, use the code below:

df_vals = df_vals[~df_vals['education'].isnull()] 

('~' indicating NOT)

Result:

   age education gender name
0   39        ma      m   n1
2   27    school      f   n3
4   36        ba      f   n5

How to add 10 days to current time in Rails

Use

Time.now + 10.days

or even

10.days.from_now

Both definitely work. Are you sure you're in Rails and not just Ruby?

If you definitely are in Rails, where are you trying to run this from? Note that Active Support has to be loaded.