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How can I restore the MySQL root user’s full privileges?

If you've deleted your root user by mistake you can do one thing:

  1. Stop MySQL service
  2. Run mysqld_safe --skip-grant-tables &
  3. Type mysql -u root -p and press enter.
  4. Enter your password
  5. At the mysql command line enter: use mysql;

Then execute this query:

insert into `user` (`Host`, `User`, `Password`, `Select_priv`, `Insert_priv`, `Update_priv`, `Delete_priv`, `Create_priv`, `Drop_priv`, `Reload_priv`, `Shutdown_priv`, `Process_priv`, `File_priv`, `Grant_priv`, `References_priv`, `Index_priv`, `Alter_priv`, `Show_db_priv`, `Super_priv`, `Create_tmp_table_priv`, `Lock_tables_priv`, `Execute_priv`, `Repl_slave_priv`, `Repl_client_priv`, `Create_view_priv`, `Show_view_priv`, `Create_routine_priv`, `Alter_routine_priv`, `Create_user_priv`, `ssl_type`, `ssl_cipher`, `x509_issuer`, `x509_subject`, `max_questions`, `max_updates`, `max_connections`, `max_user_connections`) 
values('localhost','root','','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','','','','','0','0','0','0');

then restart the mysqld

EDIT: October 6, 2018

In case anyone else needs this answer, I tried it today using innodb_version 5.6.36-82.0 and 10.1.24-MariaDB and it works if you REMOVE THE BACKTICKS (no single quotes either, just remove them):

insert into user (Host, User, Password, Select_priv, Insert_priv, Update_priv, Delete_priv, Create_priv, Drop_priv, Reload_priv, Shutdown_priv, Process_priv, File_priv, Grant_priv, References_priv, Index_priv, Alter_priv, Show_db_priv, Super_priv, Create_tmp_table_priv, Lock_tables_priv, Execute_priv, Repl_slave_priv, Repl_client_priv, Create_view_priv, Show_view_priv, Create_routine_priv, Alter_routine_priv, Create_user_priv, ssl_type, ssl_cipher, x509_issuer, x509_subject, max_questions, max_updates, max_connections, max_user_connections) 
values('localhost','root','','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','','','','','0','0','0','0');

Encrypt and Decrypt text with RSA in PHP

I have difficulty in decrypting a long string that is encrypted in python. Here is the python encryption function:

def RSA_encrypt(public_key, msg, chunk_size=214):
    """
    Encrypt the message by the provided RSA public key.

    :param public_key: RSA public key in PEM format.
    :type public_key: binary
    :param msg: message that to be encrypted
    :type msg: string
    :param chunk_size: the chunk size used for PKCS1_OAEP decryption, it is determined by \
    the private key length used in bytes - 42 bytes.
    :type chunk_size: int
    :return: Base 64 encryption of the encrypted message
    :rtype: binray
    """
    rsa_key = RSA.importKey(public_key)
    rsa_key = PKCS1_OAEP.new(rsa_key)

    encrypted = b''
    offset = 0
    end_loop = False

    while not end_loop:
        chunk = msg[offset:offset + chunk_size]

        if len(chunk) % chunk_size != 0:
            chunk += " " * (chunk_size - len(chunk))
            end_loop = True

        encrypted += rsa_key.encrypt(chunk.encode())
        offset += chunk_size

    return base64.b64encode(encrypted)

The decryption in PHP:

/**
 * @param  base64_encoded string holds the encrypted message.
 * @param  Resource your private key loaded using openssl_pkey_get_private
 * @param  integer Chunking by bytes to feed to the decryptor algorithm.
 * @return String decrypted message.
 */
public function RSADecyrpt($encrypted_msg, $ppk, $chunk_size=256){
    if(is_null($ppk))
        throw new Exception("Returned message is encrypted while you did not provide private key!");
    $encrypted_msg = base64_decode($encrypted_msg);

    $offset = 0;
    $chunk_size = 256;

    $decrypted = "";
    while($offset < strlen($encrypted_msg)){
        $decrypted_chunk = "";
        $chunk = substr($encrypted_msg, $offset, $chunk_size);

        if(openssl_private_decrypt($chunk, $decrypted_chunk, $ppk, OPENSSL_PKCS1_OAEP_PADDING))
            $decrypted .= $decrypted_chunk;
        else 
            throw new exception("Problem decrypting the message");
        $offset += $chunk_size;
    }
    return $decrypted;
}

Getting java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory exception

Try doing a complete clean of the target/deployment directory for the app to get rid of any stale library jars. Make a fresh build and check that commons-logging.jar is actually being placed in the correct lib folder. It might not be included when you are building the library for the application.

Embed YouTube Video with No Ads

Whether ads are shown on a video is up to the content owner of that video. It's not something that the embedder can control.

If you had permission from the content owners of the videos to upload copies in your own account, and then ensured that your account was set up with monetization turned off, then that would prevent ads from showing during playback. It's up to you to work out that arrangement/permission with the original videos' owners, of course.

(It's also worth pointing out that if your goal is to help non-profits raise money, then allowing them to monetize their video playbacks is in line with that goal...)

How to shutdown my Jenkins safely?

Create a Jenkins Job that runs on Master:

java -jar "%JENKINS_HOME%/war/WEB-INF/jenkins-cli.jar" -s "%JENKINS_URL%" safe-restart

AlertDialog.Builder with custom layout and EditText; cannot access view

In case any one wants it in Kotlin :

val dialogBuilder = AlertDialog.Builder(this)
// ...Irrelevant code for customizing the buttons and title
val dialogView = layoutInflater.inflate(R.layout.alert_label_editor, null)
dialogBuilder.setView(dialogView)

val editText =  dialogView.findViewById(R.id.label_field)
editText.setText("test label")
val alertDialog = dialogBuilder.create()
alertDialog.show()

Reposted @user370305's answer.

make UITableViewCell selectable only while editing

Have you tried setting the selection properties of your tableView like this:

tableView.allowsMultipleSelection = NO; tableView.allowsMultipleSelectionDuringEditing = YES; tableView.allowsSelection = NO; tableView.allowsSelectionDuringEditing YES; 

If you want more fine-grain control over when selection is allowed you can override - (NSIndexPath *)tableView:(UITableView *)tableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath in your UITableView delegate. The documentation states:

Return Value An index-path object that confirms or alters the selected row. Return an NSIndexPath object other than indexPath if you want another cell to be selected. Return nil if you don't want the row selected. 

You can have this method return nil in cases where you don't want the selection to happen.

Calculating Page Table Size

Since the Logical Address space is 32-bit long that means program size is 2^32 bytes i.e. 4GB. Now we have the page size of 4KB i.e.2^12 bytes.Thus the number of pages in program are 2^20.(no. of pages in program = program size/page size).Now the size of page table entry is 4 byte hence the size of page table is 2^20*4 = 4MB(size of page table = no. of pages in program * page table entry size). Hence 4MB space is required in Memory to store the page table.

Unit Testing: DateTime.Now

Maybe less Professional but simpler solution could be make a DateTime parameter at consumer method.For example instead of make method like SampleMethod , make SampleMethod1 with parameter.Testing of SampleMethod1 is easier

public void SampleMethod()
    {
        DateTime anotherDateTime = DateTime.Today.AddDays(-10);
        if ((DateTime.Now-anotherDateTime).TotalDays>10)
        {

        }
    }
    public void SampleMethod1(DateTime dateTimeNow)
    {
        DateTime anotherDateTime = DateTime.Today.AddDays(-10);
        if ((dateTimeNow - anotherDateTime).TotalDays > 10)
        {

        }

    }

How to use JNDI DataSource provided by Tomcat in Spring?

Documentation: C.2.3.1 <jee:jndi-lookup/> (simple)

Example:

<jee:jndi-lookup id="dataSource" jndi-name="jdbc/MyDataSource"/>

You just need to find out what JNDI name your appserver has bound the datasource to. This is entirely server-specific, consult the docs on your server to find out how.

Remember to declare the jee namespace at the top of your beans file, as described in C.2.3 The jee schema.

How to align flexbox columns left and right?

There are different ways but simplest would be to use the space-between see the example at the end

#container {    
    border: solid 1px #000;
    display: flex;    
    flex-direction: row;
    justify-content: space-between;
    padding: 10px;
    height: 50px;
}

.item {
    width: 20%;
    border: solid 1px #000;
    text-align: center;
}

see the example

Calling a class method raises a TypeError in Python

You can instantiate the class by declaring a variable and calling the class as if it were a function:

x = mystuff()
print x.average(9,18,27)

However, this won't work with the code you gave us. When you call a class method on a given object (x), it always passes a pointer to the object as the first parameter when it calls the function. So if you run your code right now, you'll see this error message:

TypeError: average() takes exactly 3 arguments (4 given)

To fix this, you'll need to modify the definition of the average method to take four parameters. The first parameter is an object reference, and the remaining 3 parameters would be for the 3 numbers.

Web link to specific whatsapp contact

The solution that worked for me is here in PHP:

$android = stripos($_SERVER['HTTP_USER_AGENT'], "android");
$iphone = stripos($_SERVER['HTTP_USER_AGENT'], "iphone");
$ipad = stripos($_SERVER['HTTP_USER_AGENT'], "ipad");

$whatsappNumber = '1234597891';
$whatsappLink = '';
if($android !== false || $ipad !== false || $iphone !== false) {//For mobile
    $whatsappLink = '<a href="https://api.whatsapp.com/send?phone='.$whatsappNumber.'">'.$whatsappNumber.'</a>';
} else {//For desktop
    $whatsappLink = '<a href="https://web.whatsapp.com/send?phone='.$whatsappNumber.'">'.$whatsappNumber.'</a>';
}

How does Django's Meta class work?

You are asking a question about two different things:

  1. Meta inner class in Django models:

    This is just a class container with some options (metadata) attached to the model. It defines such things as available permissions, associated database table name, whether the model is abstract or not, singular and plural versions of the name etc.

    Short explanation is here: Django docs: Models: Meta options

    List of available meta options is here: Django docs: Model Meta options

    For latest version of Django: Django docs: Model Meta options

  2. Metaclass in Python:

    The best description is here: What are metaclasses in Python?

How does GPS in a mobile phone work exactly?

GPS, the Global Positioning System run by the United States Military, is free for civilian use, though the reality is that we're paying for it with tax dollars.

However, GPS on cell phones is a bit more murky. In general, it won't cost you anything to turn on the GPS in your cell phone, but when you get a location it usually involves the cell phone company in order to get it quickly with little signal, as well as get a location when the satellites aren't visible (since the gov't requires a fix even if the satellites aren't visible for emergency 911 purposes). It uses up some cellular bandwidth. This also means that for phones without a regular GPS receiver, you cannot use the GPS at all if you don't have cell phone service.

For this reason most cell phone companies have the GPS in the phone turned off except for emergency calls and for services they sell you (such as directions).

This particular kind of GPS is called assisted GPS (AGPS), and there are several levels of assistance used.

GPS

A normal GPS receiver listens to a particular frequency for radio signals. Satellites send time coded messages at this frequency. Each satellite has an atomic clock, and sends the current exact time as well.

The GPS receiver figures out which satellites it can hear, and then starts gathering those messages. The messages include time, current satellite positions, and a few other bits of information. The message stream is slow - this is to save power, and also because all the satellites transmit on the same frequency and they're easier to pick out if they go slow. Because of this, and the amount of information needed to operate well, it can take 30-60 seconds to get a location on a regular GPS.

When it knows the position and time code of at least 3 satellites, a GPS receiver can assume it's on the earth's surface and get a good reading. 4 satellites are needed if you aren't on the ground and you want altitude as well.

AGPS

As you saw above, it can take a long time to get a position fix with a normal GPS. There are ways to speed this up, but unless you're carrying an atomic clock with you all the time, or leave the GPS on all the time, then there's always going to be a delay of between 5-60 seconds before you get a location.

In order to save cost, most cell phones share the GPS receiver components with the cellular components, and you can't get a fix and talk at the same time. People don't like that (especially when there's an emergency) so the lowest form of GPS does the following:

  1. Get some information from the cell phone company to feed to the GPS receiver - some of this is gross positioning information based on what cellular towers can 'hear' your phone, so by this time they already phone your location to within a city block or so.
  2. Switch from cellular to GPS receiver for 0.1 second (or some small, practically unoticable period of time) and collect the raw GPS data (no processing on the phone).
  3. Switch back to the phone mode, and send the raw data to the phone company
  4. The phone company processes that data (acts as an offline GPS receiver) and send the location back to your phone.

This saves a lot of money on the phone design, but it has a heavy load on cellular bandwidth, and with a lot of requests coming it requires a lot of fast servers. Still, overall it can be cheaper and faster to implement. They are reluctant, however, to release GPS based features on these phones due to this load - so you won't see turn by turn navigation here.

More recent designs include a full GPS chip. They still get data from the phone company - such as current location based on tower positioning, and current satellite locations - this provides sub 1 second fix times. This information is only needed once, and the GPS can keep track of everything after that with very little power. If the cellular network is unavailable, then they can still get a fix after awhile. If the GPS satellites aren't visible to the receiver, then they can still get a rough fix from the cellular towers.

But to completely answer your question - it's as free as the phone company lets it be, and so far they do not charge for it at all. I doubt that's going to change in the future. In the higher end phones with a full GPS receiver you may even be able to load your own software and access it, such as with mologogo on a motorola iDen phone - the J2ME development kit is free, and the phone is only $40 (prepaid phone with $5 credit). Unlimited internet is about $10 a month, so for $40 to start and $10 a month you can get an internet tracking system. (Prices circa August 2008)

It's only going to get cheaper and more full featured from here on out...

Re: Google maps and such

Yes, Google maps and all other cell phone mapping systems require a data connection of some sort at varying times during usage. When you move far enough in one direction, for instance, it'll request new tiles from its server. Your average phone doesn't have enough storage to hold a map of the US, nor the processor power to render it nicely. iPhone would be able to if you wanted to use the storage space up with maps, but given that most iPhones have a full time unlimited data plan most users would rather use that space for other things.

Pure CSS scroll animation

You can use my script from CodePen by just wrapping all the content within a .levit-container DIV.

~function  () {
    function Smooth () {
        this.$container = document.querySelector('.levit-container');
        this.$placeholder = document.createElement('div');
    }

    Smooth.prototype.init = function () {
        var instance = this;

        setContainer.call(instance);
        setPlaceholder.call(instance);
        bindEvents.call(instance);
    }

    function bindEvents () {
        window.addEventListener('scroll', handleScroll.bind(this), false);
    }

    function setContainer () {
        var style = this.$container.style;

        style.position = 'fixed';
        style.width = '100%';
        style.top = '0';
        style.left = '0';
        style.transition = '0.5s ease-out';
    }

    function setPlaceholder () {
        var instance = this,
                $container = instance.$container,
                $placeholder = instance.$placeholder;

        $placeholder.setAttribute('class', 'levit-placeholder');
        $placeholder.style.height = $container.offsetHeight + 'px';
        document.body.insertBefore($placeholder, $container);
    }

    function handleScroll () {
        this.$container.style.transform = 'translateZ(0) translateY(' + (window.scrollY * (- 1)) + 'px)';
    }

    var smooth = new Smooth();
    smooth.init();
}();

https://codepen.io/acauamontiel/pen/zxxebb?editors=0010

Reading a huge .csv file

If you are using pandas and have lots of RAM (enough to read the whole file into memory) try using pd.read_csv with low_memory=False, e.g.:

import pandas as pd
data = pd.read_csv('file.csv', low_memory=False)

Calling Javascript function from server side

ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "scr", "javascript:test();", true);

How to get SQL from Hibernate Criteria API (*not* for logging)

Here is a method I used and worked for me

public static String toSql(Session session, Criteria criteria){
    String sql="";
    Object[] parameters = null;
    try{
        CriteriaImpl c = (CriteriaImpl) criteria;
        SessionImpl s = (SessionImpl)c.getSession();
        SessionFactoryImplementor factory = (SessionFactoryImplementor)s.getSessionFactory();
        String[] implementors = factory.getImplementors( c.getEntityOrClassName() );
        CriteriaLoader loader = new CriteriaLoader((OuterJoinLoadable)factory.getEntityPersister(implementors[0]), factory, c, implementors[0], s.getEnabledFilters());
        Field f = OuterJoinLoader.class.getDeclaredField("sql");
        f.setAccessible(true);
        sql = (String)f.get(loader);
        Field fp = CriteriaLoader.class.getDeclaredField("traslator");
        fp.setAccessible(true);
        CriteriaQueryTranslator translator = (CriteriaQueryTranslator) fp.get(loader);
        parameters = translator.getQueryParameters().getPositionalParameterValues();
    }
    catch(Exception e){
        throw new RuntimeException(e);
    }
    if (sql !=null){
        int fromPosition = sql.indexOf(" from ");
        sql = "SELECT * "+ sql.substring(fromPosition);

        if (parameters!=null && parameters.length>0){
            for (Object val : parameters) {
                String value="%";
                if(val instanceof Boolean){
                    value = ((Boolean)val)?"1":"0";
                }else if (val instanceof String){
                    value = "'"+val+"'";
                }
                sql = sql.replaceFirst("\\?", value);
            }
        }
    }
    return sql.replaceAll("left outer join", "\nleft outer join").replace(" and ", "\nand ").replace(" on ", "\non ");
}

Unfamiliar symbol in algorithm: what does ? mean?

yes, these are the well-known quantifiers used in math. Another example is ? which reads as "exists".

http://en.wikipedia.org/wiki/Quantification

How do I debug Windows services in Visual Studio?

I'm using the /Console parameter in the Visual Studio project Debug ? Start Options ? Command line arguments:

public static class Program
{
    [STAThread]
    public static void Main(string[] args)
    {
         var runMode = args.Contains(@"/Console")
             ? WindowsService.RunMode.Console
             : WindowsService.RunMode.WindowsService;
         new WinodwsService().Run(runMode);
    }
}


public class WindowsService : ServiceBase
{
    public enum RunMode
    {
        Console,
        WindowsService
    }

    public void Run(RunMode runMode)
    {
        if (runMode.Equals(RunMode.Console))
        {
            this.StartService();
            Console.WriteLine("Press <ENTER> to stop service...");
            Console.ReadLine();

            this.StopService();
            Console.WriteLine("Press <ENTER> to exit.");
            Console.ReadLine();
        }
        else if (runMode.Equals(RunMode.WindowsService))
        {
            ServiceBase.Run(new[] { this });
        }
    }

    protected override void OnStart(string[] args)
    {
        StartService(args);
    }

    protected override void OnStop()
    {
        StopService();
    }

    /// <summary>
    /// Logic to Start Service
    /// Public accessibility for running as a console application in Visual Studio debugging experience
    /// </summary>
    public virtual void StartService(params string[] args){ ... }

    /// <summary>
    /// Logic to Stop Service
    /// Public accessibility for running as a console application in Visual Studio debugging experience
    /// </summary>
    public virtual void StopService() {....}
}

How can you flush a write using a file descriptor?

You have two choices:

  1. Use fileno() to obtain the file descriptor associated with the stdio stream pointer

  2. Don't use <stdio.h> at all, that way you don't need to worry about flush either - all writes will go to the device immediately, and for character devices the write() call won't even return until the lower-level IO has completed (in theory).

For device-level IO I'd say it's pretty unusual to use stdio. I'd strongly recommend using the lower-level open(), read() and write() functions instead (based on your later reply):

int fd = open("/dev/i2c", O_RDWR);
ioctl(fd, IOCTL_COMMAND, args);
write(fd, buf, length);

How to display my location on Google Maps for Android API v2

From android 6.0 you need to check for user permission, if you want to use GoogleMap.setMyLocationEnabled(true) you will get Call requires permission which may be rejected by user error

if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
            == PackageManager.PERMISSION_GRANTED) {
   mMap.setMyLocationEnabled(true);
} else {
// Show rationale and request permission.
}

if you want to read more, check google map docs

Check cell for a specific letter or set of letters

You can use RegExMatch:

=IF(RegExMatch(A1;"Bla");"YES";"NO")

How do I disable log messages from the Requests library?

import logging
urllib3_logger = logging.getLogger('urllib3')
urllib3_logger.setLevel(logging.CRITICAL)

In this way all the messages of level=INFO from urllib3 won't be present in the logfile.

So you can continue to use the level=INFO for your log messages...just modify this for the library you are using.

What is the difference between Select and Project Operations

PROJECT eliminates columns while SELECT eliminates rows.

How to add 10 days to current time in Rails

days, years, etc., are part of Active Support, So this won't work in irb, but it should work in rails console.

Visual Studio 2017 does not have Business Intelligence Integration Services/Projects

Information on this will probably get outdated fast because Microsoft is running to complete its work on this, but as today, June 9th 2017, support to create SQL Server Integration Services (SSIS) projects on Visual Studio 2017 is not available. So, you can't see this option because so far it doesn't exist yet.

Beyond that, even installing what is being called SSDT (SQL Server Data Tools) in VS 2017 installer (what seems very confusing from Microsoft's part, using a known name for a different thing, breaking the behavior we expect as users), you won't see SQL Server Analysis Services (SSAS) and SQL Server Reporting Services (SSRS) project templates as well.

Actually, the Business Intelligence group under the Installed templates on the New Project dialog won't be present at all.

You need to go to this page (https://docs.microsoft.com/en-us/sql/ssdt/download-sql-server-data-tools-ssdt) and install two separate installers, one for SSAS and one for SSRS.

Once you install at least one of these components, the Business Intelligence group will be created and the correspondent template(s) will be available. But as today, there is no installer for SSIS, so if you need to work with SSIS projects, you need to keep using SSDT 2015, for now.

How do I use a PriorityQueue?

Pass it a Comparator. Fill in your desired type in place of T

Using lambdas (Java 8+):

int initialCapacity = 10;
PriorityQueue<T> pq = new PriorityQueue<>(initialCapacity, (e1, e2) -> { return e1.compareTo(e2); });

Classic way, using anonymous class:

int initialCapacity = 10;
PriorityQueue<T> pq = new PriorityQueue<>(initialCapacity, new Comparator<T> () {

    @Override
    public int compare(T e1, T e2) {
        return e1.compareTo(e2);
    }

});

To sort in reverse order, simply swap e1, e2.

ORA-06508: PL/SQL: could not find program unit being called

seems like opening a new session is the key.

see this answer.

and here is an awesome explanation about this error

PHP Converting Integer to Date, reverse of strtotime

Yes you can convert it back. You can try:

date("Y-m-d H:i:s", 1388516401);

The logic behind this conversion from date to an integer is explained in strtotime in PHP:

The function expects to be given a string containing an English date format and will try to parse that format into a Unix timestamp (the number of seconds since January 1 1970 00:00:00 UTC), relative to the timestamp given in now, or the current time if now is not supplied.

For example, strtotime("1970-01-01 00:00:00") gives you 0 and strtotime("1970-01-01 00:00:01") gives you 1.

This means that if you are printing strtotime("2014-01-01 00:00:01") which will give you output 1388516401, so the date 2014-01-01 00:00:01 is 1,388,516,401 seconds after January 1 1970 00:00:00 UTC.

How to loop through an associative array and get the key?

<?php
$names = array("firstname"=>"maurice",
               "lastname"=>"muteti", 
               "contact"=>"7844433339");

foreach ($names as $name => $value) {
    echo $name." ".$value."</br>";
}

print_r($names);
?>

Prevent direct access to a php include file

Earlier mentioned solution with PHP version check added:

    $max_includes = version_compare(PHP_VERSION, '5', '<') ? 0 : 1;
    if (count(get_included_files()) <= $max_includes)
    {
        exit('Direct access is not allowed.');
    }

How to change heatmap.2 color range in R?

Here's another option for those not using heatmap.2 (aheatmap is good!)

Make a sequential vector of 100 values from min to max of your input matrix, find value closest to 0 in that, make two vector of colours to and from desired midpoint, combine and use them:

breaks <- seq(from=min(range(inputMatrix)), to=max(range(inputMatrix)), length.out=100)
midpoint <- which.min(abs(breaks - 0))
rampCol1 <- colorRampPalette(c("forestgreen", "darkgreen", "black"))(midpoint)
rampCol2 <- colorRampPalette(c("black", "darkred", "red"))(100-(midpoint+1))
rampCols <- c(rampCol1,rampCol2)

How to convert php array to utf8?

There is an easy way

array_walk_recursive(
  $array,
  function (&$entry) {
    $entry = mb_convert_encoding(
        $entry,
        'UTF-8'
    );
  }
);

Insert Data Into Tables Linked by Foreign Key

Use stored procedures.

And even assuming you would want not to use stored procedures - there is at most 3 commands to be run, not 4. Second getting id is useless, as you can do "INSERT INTO ... RETURNING".

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

People will learn your interface from code completion in their IDE or in Javadoc, not from reading the source. So there's no point in putting "public" in the source - nobody's reading the source.

How to create threads in nodejs

You might be looking for Promise.race (native I/O racing solution, not threads)

Assuming you (or others searching this question) want to race threads to avoid failure and avoid the cost of I/O operations, this is a simple and native way to accomplish it (which does not use threads). Node is designed to be single threaded (look up the event loop), so avoid using threads if possible. If my assumption is correct, I recommend you use Promise.race with setTimeout (example in link). With this strategy, you would race a list of promises which each try some I/O operation and reject the promise if there is an error (otherwise timeout). The Promise.race statement continues after the first resolution/rejection, which seems to be what you want. Hope this helps someone!

Change WPF controls from a non-main thread using Dispatcher.Invoke

japf has answer it correctly. Just in case if you are looking at multi-line actions, you can write as below.

Application.Current.Dispatcher.BeginInvoke(
  DispatcherPriority.Background,
  new Action(() => { 
    this.progressBar.Value = 50;
  }));

Information for other users who want to know about performance:

If your code NEED to be written for high performance, you can first check if the invoke is required by using CheckAccess flag.

if(Application.Current.Dispatcher.CheckAccess())
{
    this.progressBar.Value = 50;
}
else
{
    Application.Current.Dispatcher.BeginInvoke(
      DispatcherPriority.Background,
      new Action(() => { 
        this.progressBar.Value = 50;
      }));
}

Note that method CheckAccess() is hidden from Visual Studio 2015 so just write it without expecting intellisense to show it up. Note that CheckAccess has overhead on performance (overhead in few nanoseconds). It's only better when you want to save that microsecond required to perform the 'invoke' at any cost. Also, there is always option to create two methods (on with invoke, and other without) when calling method is sure if it's in UI Thread or not. It's only rarest of rare case when you should be looking at this aspect of dispatcher.

How to use a wildcard in the classpath to add multiple jars?

From: http://java.sun.com/javase/6/docs/technotes/tools/windows/classpath.html

Class path entries can contain the basename wildcard character *, which is considered equivalent to specifying a list of all the files in the directory with the extension .jar or .JAR. For example, the class path entry foo/* specifies all JAR files in the directory named foo. A classpath entry consisting simply of * expands to a list of all the jar files in the current directory.

This should work in Java6, not sure about Java5

(If it seems it does not work as expected, try putting quotes. eg: "foo/*")

Failed to connect to camera service

since this question was asked 4 years back..and i didn't realised that unless mentioned by the Questioner..when there were no Run time permissions support.

but hoping it useful for the users who still caught in this situation.. Have a look at Run Time Permissions ,for me it solved the problem when i added Run time permissions to grant camera access. Alternatively you can grant permissions to the app manually by going to your mobile settings=>Apps=>(select your app)=>Permissions section in the appeared window and enable/disable desired permissions. hope this will work.

New line character in VB.Net?

you can solve that problem in visual basic .net without concatenating your text, you can use this as a return type of your overloaded Tostring:

System.Text.RegularExpressions.Regex.Unescape(String.format("FirstName:{0} \r\n LastName: {1}", "Nordanne", "Isahac"))

How do you reverse a string in place in C or C++?

Another C++ way (though I would probably use std::reverse() myself :) as being more expressive and faster)

str = std::string(str.rbegin(), str.rend());

The C way (more or less :) ) and please, be careful about XOR trick for swapping, compilers sometimes cannot optimize that.

In such case it is usually much slower.

char* reverse(char* s)
{
    char* beg = s, *end = s, tmp;
    while (*end) end++;
    while (end-- > beg)
    { 
        tmp  = *beg; 
        *beg++ = *end;  
        *end =  tmp;
    }
    return s;
} // fixed: check history for details, as those are interesting ones

jQuery, get ID of each element in a class using .each?

Try this, replacing .myClassName with the actual name of the class (but keep the period at the beginning).

$('.myClassName').each(function() {
    alert( this.id );
});

So if the class is "test", you'd do $('.test').each(func....

This is the specific form of .each() that iterates over a jQuery object.

The form you were using iterates over any type of collection. So you were essentially iterating over an array of characters t,e,s,t.

Using that form of $.each(), you would need to do it like this:

$.each($('.myClassName'), function() {
    alert( this.id );
});

...which will have the same result as the example above.

PowerShell: how to grep command output?

Your problem is that alias emits a stream of AliasInfo objects, rather than a stream of strings. This does what I think you want.

alias | out-string -stream | select-string Alias

or as a function

function grep {
  $input | out-string -stream | select-string $args
}

alias | grep Alias

When you don't handle things that are in the pipeline (like when you just ran 'alias'), the shell knows to use the ToString() method on each object (or use the output formats specified in the ETS info).

ng is not recognized as an internal or external command

PATH environment variable should be updated by adding following path,

C:\Users\xyzname\AppData\Roaming\npm\node_modules\@angular\cli\bin

Because ng file is in bin folder, once this is added for sure ng will be recognized

Evaluating string "3*(4+2)" yield int 18

Short answer: I don't think so. C# .Net is compiled (to bytecode) and can't evaluate strings at runtime, as far as I know. JScript .Net can, however; but I would still advise you to code a parser and stack-based evaluator yourself.

How to determine if binary tree is balanced?

Well, you need a way to determine the heights of left and right, and if left and right are balanced.

And I'd just return height(node->left) == height(node->right);

As to writing a height function, read: Understanding recursion

How do you create a toggle button?

I would be inclined to use a class in your css that alters the border style or border width when the button is depressed, so it gives the appearance of a toggle button.

How do I do a HTTP GET in Java?

Technically you could do it with a straight TCP socket. I wouldn't recommend it however. I would highly recommend you use Apache HttpClient instead. In its simplest form:

GetMethod get = new GetMethod("http://httpcomponents.apache.org");
// execute method and handle any error responses.
...
InputStream in = get.getResponseBodyAsStream();
// Process the data from the input stream.
get.releaseConnection();

and here is a more complete example.

Create a directory if it does not exist and then create the files in that directory as well

If you create a web based application, the better solution is to check the directory exists or not then create the file if not exist. If exists, recreate again.

    private File createFile(String path, String fileName) throws IOException {
       ClassLoader classLoader = getClass().getClassLoader();
       File file = new File(classLoader.getResource(".").getFile() + path + fileName);

       // Lets create the directory
       try {
          file.getParentFile().mkdir();
       } catch (Exception err){
           System.out.println("ERROR (Directory Create)" + err.getMessage());
       }

       // Lets create the file if we have credential
       try {
           file.createNewFile();
       } catch (Exception err){
           System.out.println("ERROR (File Create)" + err.getMessage());
       }
       return  file;
   }

Choose folders to be ignored during search in VS Code

I wanted to exclude 1 of the Workspace folders completely, but found this to be difficult, since regardless of the exclusion patterns, it always runs the search on each of the Workspace folders.

In the end, the solution was to add ** to the Folder Settings search exclusion patterns.

enter image description here

How can I set NODE_ENV=production on Windows?

My experience using Node.js on Windows 7 64-bit in Visual Studio 2013 is that you need to use

setx NODE_ENV development

from a cmd window. AND you have to restart Visual Studio in order for the new value to be recognized.

The set syntax only lasts for the duration of the cmd window in which it is set.

Simple test in Node.js:

console.log('process.env.NODE_ENV = ' + process.env.NODE_ENV);

It returns 'undefined' when using set, and it will return 'development' if using setx and restarting Visual Studio.

What is the { get; set; } syntax in C#?

In the Visual Studio, if you define a property X in a class and you want to use this class only as a type, after building your project you will get a warning that says "Field X is never assigned to, and will always has its default value".

By adding a { get; set; } to X property, you will not get this warning.

In addition in Visual Studio 2013 and upper versions, by adding { get; set; } you are able to see all references to that property.

enter image description here

How to concatenate string variables in Bash

Yet another approach...

> H="Hello "
> U="$H""universe."
> echo $U
Hello universe.

...and yet yet another one.

> H="Hello "
> U=$H"universe."
> echo $U
Hello universe.

How to make a rest post call from ReactJS code?

As of 2018 and beyond, you have a more modern option which is to incorporate async/await in your ReactJS application. A promise-based HTTP client library such as axios can be used. The sample code is given below:

import axios from 'axios';
...
class Login extends Component {
    constructor(props, context) {
        super(props, context);
        this.onLogin = this.onLogin.bind(this);
        ...
    }
    async onLogin() {
        const { email, password } = this.state;
        try {
           const response = await axios.post('/login', { email, password });
           console.log(response);
        } catch (err) {
           ...
        }
    }
    ...
}

Check box size change with CSS

input fields can be styled as you wish. So instead of zoom, you could have

input[type="checkbox"]{
  width: 30px; /*Desired width*/
  height: 30px; /*Desired height*/
}

EDIT:

You would have to add extra rules like this:

input[type="checkbox"]{
  width: 30px; /*Desired width*/
  height: 30px; /*Desired height*/
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}

Check this fiddle http://jsfiddle.net/p36tqqyq/1/

How do I remove a single file from the staging area (undo git add)?

After version 2.23, Git has introduced the git restore command which you can use to do that. Quoting the official documentation:

Restore specified paths in the working tree with some contents from a restore source. If a path is tracked but does not exist in the restore source, it will be removed to match the source.

The command can also be used to restore the content in the index with --staged, or restore both the working tree and the index with --staged --worktree.

So you can invoke git restore --staged <path> and unstage the file but also keep the changes you made. Remember that if the file was not staged you lose all the changes you made to it.

How to print a certain line of a file with PowerShell?

This will show the 10th line of myfile.txt:

get-content myfile.txt | select -first 1 -skip 9

both -first and -skip are optional parameters, and -context, or -last may be useful in similar situations.

How to check for empty value in Javascript?

First, I would check what i gets initialized to, to see if the elements returned by getElementsByName are what you think they are. Maybe split the problem by trying it with a hard-coded name like timetemp0, without the concatenation. You can also run the code through a browser debugger (FireBug, Chrome Dev Tools, IE Dev Tools).

Also, for your if-condition, this should suffice:

if (!timetemp[0].value) {
    // The value is empty.
}
else {
    // The value is not empty.
}

The empty string in Javascript is a falsey value, so the logical negation of that will get you into the if-block.

Use sudo with password as parameter

You can set the s bit for your script so that it does not need sudo and runs as root (and you do not need to write your root password in the script):

sudo chmod +s myscript

Error pushing to GitHub - insufficient permission for adding an object to repository database

OK - turns out it was a permissions problem on GitHub that happened during the fork of emi/bixo to bixo/bixo. Once Tekkub fixed these, it started working again.

How to align input forms in HTML

You should use a table. As a matter of logical structure the data is tabular: this is why you want it to align, because you want to show that the labels are not related solely to their input boxes but also to each other, in a two-dimensional structure.

[consider what you would do if you had string or numeric values to display instead of input boxes.]

How to represent e^(-t^2) in MATLAB?

If t is a matrix, you need to use the element-wise multiplication or exponentiation. Note the dot.

x = exp( -t.^2 )

or

x = exp( -t.*t )

ASP.NET DateTime Picker

@Html.EditorFor(model => model.Date, new { htmlAttributes = new { @class = "form-control", @type = "date" } })

this works well

Core dump file is not generated

Also, check to make sure you have enough disk space on /var/core or wherever your core dumps get written. If the partition is almos full or at 100% disk usage then that would be the problem. My core dumps average a few gigs so you should be sure to have at least 5-10 gig available on the partition.

How do I prevent Conda from activating the base environment by default?

I have conda 4.6 with a similar block of code that was added by conda. In my case, there's a conda configuration setting to disable the automatic base activation:

conda config --set auto_activate_base false

The first time you run it, it'll create a ./condarc in your home directory with that setting to override the default.

This wouldn't de-clutter your .bash_profile but it's a cleaner solution without manual editing that section that conda manages.

addClass - can add multiple classes on same div?

You can do

$('.page-address-edit').addClass('test1 test2');

More here:

More than one class may be added at a time, separated by a space, to the set of matched elements, like so:

$("p").addClass("myClass yourClass");

Will Google Android ever support .NET?

Yes, it will be possible and it won't be that difficult. All what's needed at this point to start with is some kind of converter that will turn MSIL into Dalvik bytecode. Since both formats are open-sourced and well documented, there won't be any problem with it.

So, writing Android applications in C# or VB.NET will be possible, question is how much of .NET framework standard libraries will be supported. But that's another issue.

Oscar Reyes wrote:

I'm pretty sure if google hand ANY interest in .net, they would've design something while Android was in the first stages, not now when they are in production stages. I don't mean it is not possible, what I'm saying is they're not interested. Maybe in mmm hhhh 10 yrs.

Actually what they've already designed is very compatible with Java and .NET

They can't do everything at once, but if you look into Android SDK, there is a tool called dx. This tool converts Java bytecode into Dalvik bytecode, so in other words, you can run programs written in Java on Android with no effort today. Now the same tool is needed for .NET.

Considering how similar .NET and Java are, it's really a matter of time.

ddimitrov wrote:

The .Net->Java->Dalvik translation can be done even now (http://dev.mainsoft.com/), but I think you underestimate the lack of .Net libraries. Of course somebody can port Mono, but it's definitely a non-trivial effort.

No need to port Mono. Android already has VM and some basic API. All what's needed is CIL->Dalvik converter and tiny .NET wrapper for Android API (and maybe some basic implementation of some standard .NET classes). That's it.

Update: .NET already works on Android - you will need product called Monodroid (http://monodroid.net) as stated above.

Can I have onScrollListener for a ScrollView?

You can use NestedScrollView instead of ScrollView. However, when using a Kotlin Lambda, it won't know you want NestedScrollView's setOnScrollChangeListener instead of the one at View (which is API level 23). You can fix this by specifying the first parameter as a NestedScrollView.

nestedScrollView.setOnScrollChangeListener { _: NestedScrollView, scrollX: Int, scrollY: Int, _: Int, _: Int ->
    Log.d("ScrollView", "Scrolled to $scrollX, $scrollY")
}

How to add a hook to the application context initialization event?

Create your annotation

  @Retention(RetentionPolicy.RUNTIME)
    public @interface AfterSpringLoadComplete {
    }

Create class

    public class PostProxyInvokerContextListener implements ApplicationListener<ContextRefreshedEvent> {

    @Autowired
    ConfigurableListableBeanFactory factory;

    @Override
    public void onApplicationEvent(ContextRefreshedEvent event) {
        ApplicationContext context = event.getApplicationContext();
        String[] names = context.getBeanDefinitionNames();
        for (String name : names) {
            try {
                BeanDefinition definition = factory.getBeanDefinition(name);
                String originalClassName = definition.getBeanClassName();
                Class<?> originalClass = Class.forName(originalClassName);
                Method[] methods = originalClass.getMethods();
                for (Method method : methods) {
                    if (method.isAnnotationPresent(AfterSpringLoadComplete.class)){
                        Object bean = context.getBean(name);
                        Method currentMethod = bean.getClass().getMethod(method.getName(), method.getParameterTypes());
                        currentMethod.invoke(bean);
                    }
                }
            } catch (Exception ignored) {
            }
        }
    }
}

Register this class by @Component annotation or in xml

<bean class="ua.adeptius.PostProxyInvokerContextListener"/>

and use annotation where you wan on any method that you want to run after context initialized, like:

   @AfterSpringLoadComplete
    public void init() {}

Everytime I run gulp anything, I get a assertion error. - Task function must be specified

I get the same error when using Gulp. The solution is to switch to Gulp version 3.9.1, both for the local version and the CLI version.

sudo npm install -g [email protected]

Run in the project's folder

npm install [email protected]

ios simulator: how to close an app

I had a difficult time in finding a way in XCode 7.2, but finally I had found one. First press Shift+Command+ H twice. This will open up all the apps that are currently open.

Swipe left/right to the app you actually want to close. Just Swipe Up using the Touchpad while Holding the App would close the app.

Regex match entire words only

For Those who want to validate an Enum in their code you can following the guide

In Regex World you can use ^ for starting a string and $ to end it. Using them in combination with | could be what you want :

^(Male)$|^(Female)$

It will return true only for Male or Female case.

bash: npm: command not found?

If you already installed npm globally on your system, and you are still getting the above error message by using VSCode terminal. Just close your VSCode application and reopen again, that should resolve the issue.

Check if string contains only letters in javascript

The fastest way is to check if there is a non letter:

if (!/[^a-zA-Z]/.test(word))

Better/Faster to Loop through set or list?

I the list is vary large looping two time over it will take a lot of time and more in the second time you are looping a set not a list and as we know iterating over a set is slower than list.

i think you need the power of generator and set.

def first_test():

    def loop_one_time(my_list):
        # create a set to keep the items.
        iterated_items = set()
        # as we know iterating over list is faster then list.
        for value in my_list: 
            # as we know checking if element exist in set is very fast not
            # metter the size of the set.
            if value not in iterated_items:  
                iterated_items.add(value) # add this item to list
                yield value


    mylist = [3,1,5,2,4,4,1,4,2,5,1,3]

    for v in loop_one_time(mylist):pass



def second_test():
    mylist = [3,1,5,2,4,4,1,4,2,5,1,3]
    s = set(mylist)
    for v in s:pass


import timeit

print(timeit.timeit('first_test()', setup='from __main__ import first_test', number=10000))
print(timeit.timeit('second_test()', setup='from __main__ import second_test', number=10000))

out put:

   0.024003583388435043
   0.010424674188938422

Note: this technique order is guaranteed

A simple explanation of Naive Bayes Classification

I realize that this is an old question, with an established answer. The reason I'm posting is that is the accepted answer has many elements of k-NN (k-nearest neighbors), a different algorithm.

Both k-NN and NaiveBayes are classification algorithms. Conceptually, k-NN uses the idea of "nearness" to classify new entities. In k-NN 'nearness' is modeled with ideas such as Euclidean Distance or Cosine Distance. By contrast, in NaiveBayes, the concept of 'probability' is used to classify new entities.

Since the question is about Naive Bayes, here's how I'd describe the ideas and steps to someone. I'll try to do it with as few equations and in plain English as much as possible.

First, Conditional Probability & Bayes' Rule

Before someone can understand and appreciate the nuances of Naive Bayes', they need to know a couple of related concepts first, namely, the idea of Conditional Probability, and Bayes' Rule. (If you are familiar with these concepts, skip to the section titled Getting to Naive Bayes')

Conditional Probability in plain English: What is the probability that something will happen, given that something else has already happened.

Let's say that there is some Outcome O. And some Evidence E. From the way these probabilities are defined: The Probability of having both the Outcome O and Evidence E is: (Probability of O occurring) multiplied by the (Prob of E given that O happened)

One Example to understand Conditional Probability:

Let say we have a collection of US Senators. Senators could be Democrats or Republicans. They are also either male or female.

If we select one senator completely randomly, what is the probability that this person is a female Democrat? Conditional Probability can help us answer that.

Probability of (Democrat and Female Senator)= Prob(Senator is Democrat) multiplied by Conditional Probability of Being Female given that they are a Democrat.

  P(Democrat & Female) = P(Democrat) * P(Female | Democrat) 

We could compute the exact same thing, the reverse way:

  P(Democrat & Female) = P(Female) * P(Democrat | Female) 

Understanding Bayes Rule

Conceptually, this is a way to go from P(Evidence| Known Outcome) to P(Outcome|Known Evidence). Often, we know how frequently some particular evidence is observed, given a known outcome. We have to use this known fact to compute the reverse, to compute the chance of that outcome happening, given the evidence.

P(Outcome given that we know some Evidence) = P(Evidence given that we know the Outcome) times Prob(Outcome), scaled by the P(Evidence)

The classic example to understand Bayes' Rule:

Probability of Disease D given Test-positive = 

               P(Test is positive|Disease) * P(Disease)
     _______________________________________________________________
     (scaled by) P(Testing Positive, with or without the disease)

Now, all this was just preamble, to get to Naive Bayes.

Getting to Naive Bayes'

So far, we have talked only about one piece of evidence. In reality, we have to predict an outcome given multiple evidence. In that case, the math gets very complicated. To get around that complication, one approach is to 'uncouple' multiple pieces of evidence, and to treat each of piece of evidence as independent. This approach is why this is called naive Bayes.

P(Outcome|Multiple Evidence) = 
P(Evidence1|Outcome) * P(Evidence2|outcome) * ... * P(EvidenceN|outcome) * P(Outcome)
scaled by P(Multiple Evidence)

Many people choose to remember this as:

                      P(Likelihood of Evidence) * Prior prob of outcome
P(outcome|evidence) = _________________________________________________
                                         P(Evidence)

Notice a few things about this equation:

  • If the Prob(evidence|outcome) is 1, then we are just multiplying by 1.
  • If the Prob(some particular evidence|outcome) is 0, then the whole prob. becomes 0. If you see contradicting evidence, we can rule out that outcome.
  • Since we divide everything by P(Evidence), we can even get away without calculating it.
  • The intuition behind multiplying by the prior is so that we give high probability to more common outcomes, and low probabilities to unlikely outcomes. These are also called base rates and they are a way to scale our predicted probabilities.

How to Apply NaiveBayes to Predict an Outcome?

Just run the formula above for each possible outcome. Since we are trying to classify, each outcome is called a class and it has a class label. Our job is to look at the evidence, to consider how likely it is to be this class or that class, and assign a label to each entity. Again, we take a very simple approach: The class that has the highest probability is declared the "winner" and that class label gets assigned to that combination of evidences.

Fruit Example

Let's try it out on an example to increase our understanding: The OP asked for a 'fruit' identification example.

Let's say that we have data on 1000 pieces of fruit. They happen to be Banana, Orange or some Other Fruit. We know 3 characteristics about each fruit:

  1. Whether it is Long
  2. Whether it is Sweet and
  3. If its color is Yellow.

This is our 'training set.' We will use this to predict the type of any new fruit we encounter.

Type           Long | Not Long || Sweet | Not Sweet || Yellow |Not Yellow|Total
             ___________________________________________________________________
Banana      |  400  |    100   || 350   |    150    ||  450   |  50      |  500
Orange      |    0  |    300   || 150   |    150    ||  300   |   0      |  300
Other Fruit |  100  |    100   || 150   |     50    ||   50   | 150      |  200
            ____________________________________________________________________
Total       |  500  |    500   || 650   |    350    ||  800   | 200      | 1000
             ___________________________________________________________________

We can pre-compute a lot of things about our fruit collection.

The so-called "Prior" probabilities. (If we didn't know any of the fruit attributes, this would be our guess.) These are our base rates.

 P(Banana)      = 0.5 (500/1000)
 P(Orange)      = 0.3
 P(Other Fruit) = 0.2

Probability of "Evidence"

p(Long)   = 0.5
P(Sweet)  = 0.65
P(Yellow) = 0.8

Probability of "Likelihood"

P(Long|Banana) = 0.8
P(Long|Orange) = 0  [Oranges are never long in all the fruit we have seen.]
 ....

P(Yellow|Other Fruit)     =  50/200 = 0.25
P(Not Yellow|Other Fruit) = 0.75

Given a Fruit, how to classify it?

Let's say that we are given the properties of an unknown fruit, and asked to classify it. We are told that the fruit is Long, Sweet and Yellow. Is it a Banana? Is it an Orange? Or Is it some Other Fruit?

We can simply run the numbers for each of the 3 outcomes, one by one. Then we choose the highest probability and 'classify' our unknown fruit as belonging to the class that had the highest probability based on our prior evidence (our 1000 fruit training set):

P(Banana|Long, Sweet and Yellow) 
      P(Long|Banana) * P(Sweet|Banana) * P(Yellow|Banana) * P(banana)
    = _______________________________________________________________
                      P(Long) * P(Sweet) * P(Yellow)
                      
    = 0.8 * 0.7 * 0.9 * 0.5 / P(evidence)

    = 0.252 / P(evidence)


P(Orange|Long, Sweet and Yellow) = 0


P(Other Fruit|Long, Sweet and Yellow)
      P(Long|Other fruit) * P(Sweet|Other fruit) * P(Yellow|Other fruit) * P(Other Fruit)
    = ____________________________________________________________________________________
                                          P(evidence)

    = (100/200 * 150/200 * 50/200 * 200/1000) / P(evidence)

    = 0.01875 / P(evidence)

By an overwhelming margin (0.252 >> 0.01875), we classify this Sweet/Long/Yellow fruit as likely to be a Banana.

Why is Bayes Classifier so popular?

Look at what it eventually comes down to. Just some counting and multiplication. We can pre-compute all these terms, and so classifying becomes easy, quick and efficient.

Let z = 1 / P(evidence). Now we quickly compute the following three quantities.

P(Banana|evidence) = z * Prob(Banana) * Prob(Evidence1|Banana) * Prob(Evidence2|Banana) ...
P(Orange|Evidence) = z * Prob(Orange) * Prob(Evidence1|Orange) * Prob(Evidence2|Orange) ...
P(Other|Evidence)  = z * Prob(Other)  * Prob(Evidence1|Other)  * Prob(Evidence2|Other)  ...

Assign the class label of whichever is the highest number, and you are done.

Despite the name, Naive Bayes turns out to be excellent in certain applications. Text classification is one area where it really shines.

Hope that helps in understanding the concepts behind the Naive Bayes algorithm.

SQL ROWNUM how to return rows between a specific range

I know this is an old question, however, it is useful to mention the new features in the latest version.

From Oracle 12c onwards, you could use the new Top-n Row limiting feature. No need to write a subquery, no dependency on ROWNUM.

For example, the below query would return the employees between 4th highest till 7th highest salaries in ascending order:

SQL> SELECT empno, sal
  2  FROM   emp
  3  ORDER BY sal
  4  OFFSET 4 ROWS FETCH NEXT 4 ROWS ONLY;

     EMPNO        SAL
---------- ----------
      7654       1250
      7934       1300
      7844       1500
      7499       1600

SQL>

Storing data into list with class

You're not adding a new instance of the class to the list. Try this:

lstemail.Add(new EmailData { FirstName="John", LastName="Smith", Location="Los Angeles" });`

List is a generic class. When you specify a List<EmailData>, the Add method is expecting an object that's of type EmailData. The example above, expressed in more verbose syntax, would be:

EmailData data = new EmailData();
data.FirstName="John";
data.LastName="Smith;
data.Location = "Los Angeles";
lstemail.Add(data);

Assigning default value while creating migration file

Default migration generator does not handle default values (column modifiers are supported but do not include default or null), but you could create your own generator.

You can also manually update the migration file prior to running rake db:migrate by adding the options to add_column:

add_column :tweet, :retweets_count, :integer, :null => false, :default => 0

... and read Rails API

The transaction manager has disabled its support for remote/network transactions

I had a store procedure that call another store Procedure in "linked server".when I execute it in ssms it was ok,but when I call it in application(By Entity Framework),I got this error. This article helped me and I used this script:

EXEC sp_serveroption @server = 'LinkedServer IP or Name',@optname = 'remote proc transaction promotion', @optvalue = 'false' ;

for more detail look at this: Linked server : The partner transaction manager has disabled its support for remote/network transactions

Integration Testing POSTing an entire object to Spring MVC controller

One of the main purposes of integration testing with MockMvc is to verify that model objects are correclty populated with form data.

In order to do it you have to pass form data as they're passed from actual form (using .param()). If you use some automatic conversion from NewObject to from data, your test won't cover particular class of possible problems (modifications of NewObject incompatible with actual form).

Correct way to quit a Qt program?

If you're using Qt Jambi, this should work:

QApplication.closeAllWindows();

How do you fade in/out a background color using jquery?

If you want to specifically animate the background color of an element, I believe you need to include jQueryUI framework. Then you can do:

$('#myElement').animate({backgroundColor: '#FF0000'}, 'slow');

jQueryUI has some built-in effects that may be useful to you as well.

http://jqueryui.com/demos/effect/

Iframe positioning

you have to use this css property,

 position:relative;

use it for your #contentframe div tag

Check if checkbox is checked with jQuery

Toggle checkbox checked

$("#checkall").click(function(){
    $("input:checkbox").prop( 'checked',$(this).is(":checked") );
})

Set environment variables on Mac OS X Lion

Your .profile or .bash_profile are simply files that are present in your "home" folder. If you open a Finder window and click your account name in the Favorites pane, you won't see them. If you open a Terminal window and type ls to list files you still won't see them. However, you can find them by using ls -a in the terminal. Or if you open your favorite text editor (say TextEdit since it comes with OS X) and do File->Open and then press Command+Shift+. and click on your account name (home folder) you will see them as well. If you do not see them, then you can create one in your favorite text editor.

Now, adding environment variables is relatively straightforward and remarkably similar to windows conceptually. In your .profile just add, one per line, the variable name and its value as follows:

export JAVA_HOME=/Library/Java/Home
export JRE_HOME=/Library/Java/Home

etc.

If you are modifying your "PATH" variable, be sure to include the system's default PATH that was already set for you:

export PATH=$PATH:/path/to/my/stuff

Now here is the quirky part, you can either open a new Terminal window to have the new variables take effect, or you will need to type .profile or .bash_profile to reload the file and have the contents be applied to your current Terminal's environment.

You can check that your changes took effect using the "set" command in your Terminal. Just type set (or set | more if you prefer a paginated list) and be sure what you added to the file is there.

As for adding environment variables to GUI apps, that is normally not necessary and I'd like to hear more about what you are specifically trying to do to better give you an answer for it.

What do these operators mean (** , ^ , %, //)?

  • **: exponentiation
  • ^: exclusive-or (bitwise)
  • %: modulus
  • //: divide with integral result (discard remainder)

Selecting all text in HTML text input when clicked

You can use this javascript snippet:

<input onClick="this.select();" value="Sample Text" />

But apparently it doesn't work on mobile Safari. In those cases you can use:

<input onClick="this.setSelectionRange(0, this.value.length)" value="Sample Text" />

Most efficient solution for reading CLOB to String, and String to CLOB in Java?

My answer is just a flavor of the same. But I tested it with serializing a zipped content and it worked. So I can trust this solution unlike the one offered first (that use readLine) because it will ignore line breaks and corrupt the input.

/*********************************************************************************************
 * From CLOB to String
 * @return string representation of clob
 *********************************************************************************************/
private String clobToString(java.sql.Clob data)
{
    final StringBuilder sb = new StringBuilder();

    try
    {
        final Reader         reader = data.getCharacterStream();
        final BufferedReader br     = new BufferedReader(reader);

        int b;
        while(-1 != (b = br.read()))
        {
            sb.append((char)b);
        }

        br.close();
    }
    catch (SQLException e)
    {
        log.error("SQL. Could not convert CLOB to string",e);
        return e.toString();
    }
    catch (IOException e)
    {
        log.error("IO. Could not convert CLOB to string",e);
        return e.toString();
    }

    return sb.toString();
}

Send password when using scp to copy files from one server to another

Here is how I resolved it.

It is not the most secure way however it solved my problem as security was not an issue on internal servers.

Create a new file say password.txt and store the password for the server where the file will be pasted. Save this to a location on the host server.

scp -W location/password.txt copy_file_location paste_file_location

Cheers!

How to check for null in Twig?

Depending on what exactly you need:

  • is null checks whether the value is null:

    {% if var is null %}
        {# do something #}
    {% endif %}
    
  • is defined checks whether the variable is defined:

    {% if var is not defined %}
        {# do something #}
    {% endif %}
    

Additionally the is sameas test, which does a type strict comparison of two values, might be of interest for checking values other than null (like false):

{% if var is sameas(false) %}
    {# do something %}
{% endif %}

Copy all files with a certain extension from all subdirectories

I had a similar problem. I solved it using:

find dir_name '*.mp3' -exec cp -vuni '{}' "../dest_dir" ";"

The '{}' and ";" executes the copy on each file.

Using Address Instead Of Longitude And Latitude With Google Maps API

var geocoder;
var map;
function initialize() {
geocoder = new google.maps.Geocoder();
var latlng = new google.maps.LatLng(-34.397, 150.644);
var mapOptions = {
  zoom: 8,
  center: latlng
}
map = new google.maps.Map(document.getElementById('map'), mapOptions);
}

function codeAddress() {
var address = document.getElementById('address').value;
geocoder.geocode( { 'address': address}, function(results, status) {
  if (status == 'OK') {
    map.setCenter(results[0].geometry.location);
    var marker = new google.maps.Marker({
        map: map,
        position: results[0].geometry.location
    });
  } else {
    alert('Geocode was not successful for the following reason: ' + status);
  }
});
}

<body onload="initialize()">
 <div id="map" style="width: 320px; height: 480px;"></div>
 <div>
   <input id="address" type="textbox" value="Sydney, NSW">
   <input type="button" value="Encode" onclick="codeAddress()">
 </div>
</body>

Or refer to the documentation https://developers.google.com/maps/documentation/javascript/geocoding

Powershell script to check if service is started, if not then start it

Trying to do things as smooth as possible - I here suggest modifying GuyWhoLikesPowershell's suggestion slightly.

I replaced the if and until with one while - and I check for "Stopped", since I don't want to start if status is "starting" or " Stopping".

$Service = 'ServiceName'
while ((Get-Service $Service).Status -eq 'Stopped') 
{
    Start-Service $Service -ErrorAction SilentlyContinue
    Start-Sleep 10
} 
Return "$($Service) has STARTED"

ParseError: not well-formed (invalid token) using cElementTree

This is most probably an encoding error. For example I had an xml file encoded in UTF-8-BOM (checked from the Notepad++ Encoding menu) and got similar error message.

The workaround (Python 3.6)

import io
from xml.etree import ElementTree as ET

with io.open(file, 'r', encoding='utf-8-sig') as f:
    contents = f.read()
    tree = ET.fromstring(contents)

Check the encoding of your xml file. If it is using different encoding, change the 'utf-8-sig' accordingly.

Do I need <class> elements in persistence.xml?

Hibernate doesn't support <exclude-unlisted-classes>false</exclude-unlisted-classes> under SE, (another poster mentioned this works with TopLink and EclipseLink).

There are tools that will auto-generate the list of classes to persistence.xml e.g. the Import Database Schema wizard in IntelliJ. Once you've got your project's initial classes in persistence.xml it should be simple to add/remove single classes by hand as your project progresses.

How do I set the proxy to be used by the JVM

Combining Sorter's and javabrett/Leonel's answers:

java -Dhttp.proxyHost=10.10.10.10 -Dhttp.proxyPort=8080 -Dhttp.proxyUser=username -Dhttp.proxyPassword=password -jar myJar.jar

C++ Passing Pointer to Function (Howto) + C++ Pointer Manipulation

To pass a pointer to an int it should be void Fun(int* pointer).

Passing a reference to an int would look like this...

void Fun(int& ref) {
   ref = 10;
}

int main() {
   int test = 5;
   cout << test << endl;  // prints 5

   Fun(test);
   cout << test << endl;  // prints 10 because Fun modified the value

   return 1;
}

How to instantiate, initialize and populate an array in TypeScript?

There isn't a field initialization syntax like that for objects in JavaScript or TypeScript.

Option 1:

class bar {
    // Makes a public field called 'length'
    constructor(public length: number) { }
}

bars = [ new bar(1) ];

Option 2:

interface bar {
    length: number;
}

bars = [ {length: 1} ];

Optional Parameters in Web Api Attribute Routing

Another info: If you want use a Route Constraint, imagine that you want force that parameter has int datatype, then you need use this syntax:

[Route("v1/location/**{deviceOrAppid:int?}**", Name = "AddNewLocation")]

The ? character is put always before the last } character

For more information see: Optional URI Parameters and Default Values

How to center Font Awesome icons horizontally?

i solved my problem with this:

<div class="d-flex justify-content-center"></div>

im using bootstrap with font awesome icons.

if you want to know more acess the link below: https://getbootstrap.com/docs/4.0/utilities/flex/

jQuery move to anchor location on page load

Description

You can do this using jQuery's .scrollTop() and .offset() method

Check out my sample and this jsFiddle Demonstration

Sample

$(function() {
    $(document).scrollTop( $("#header").offset().top );  
});

More Information

Apply function to pandas groupby

I saw a nested function technique for computing a weighted average on S.O. one time, altering that technique can solve your issue.

def group_weight(overall_size):
    def inner(group):
        return len(group)/float(overall_size)
    inner.__name__ = 'weight'
    return inner

d = {"my_label": pd.Series(['A','B','A','C','D','D','E'])}
df = pd.DataFrame(d)
print df.groupby('my_label').apply(group_weight(len(df)))



my_label
A    0.285714
B    0.142857
C    0.142857
D    0.285714
E    0.142857
dtype: float64

Here is how to do a weighted average within groups

def wavg(val_col_name,wt_col_name):
    def inner(group):
        return (group[val_col_name] * group[wt_col_name]).sum() / group[wt_col_name].sum()
    inner.__name__ = 'wgt_avg'
    return inner



d = {"P": pd.Series(['A','B','A','C','D','D','E'])
     ,"Q": pd.Series([1,2,3,4,5,6,7])
    ,"R": pd.Series([0.1,0.2,0.3,0.4,0.5,0.6,0.7])
     }

df = pd.DataFrame(d)
print df.groupby('P').apply(wavg('Q','R'))

P
A    2.500000
B    2.000000
C    4.000000
D    5.545455
E    7.000000
dtype: float64

jQuery or JavaScript auto click

$(document).ready(function(){
   $('.lbOn').click();
});

Suppose this would work too.

How to program a delay in Swift 3

Try the following function implemented in Swift 3.0 and above

func delayWithSeconds(_ seconds: Double, completion: @escaping () -> ()) {
    DispatchQueue.main.asyncAfter(deadline: .now() + seconds) { 
        completion()
    }
}

Usage

delayWithSeconds(1) {
   //Do something
}

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

This worked for me for a format like YYYY.MM.DD-HH.MM.SS.fff. Attempting to make this code capable of accepting any string format will be like reinventing the wheel (i.e. there are functions for all this in Boost.

std::chrono::system_clock::time_point string_to_time_point(const std::string &str)
{
    using namespace std;
    using namespace std::chrono;

    int yyyy, mm, dd, HH, MM, SS, fff;

    char scanf_format[] = "%4d.%2d.%2d-%2d.%2d.%2d.%3d";

    sscanf(str.c_str(), scanf_format, &yyyy, &mm, &dd, &HH, &MM, &SS, &fff);

    tm ttm = tm();
    ttm.tm_year = yyyy - 1900; // Year since 1900
    ttm.tm_mon = mm - 1; // Month since January 
    ttm.tm_mday = dd; // Day of the month [1-31]
    ttm.tm_hour = HH; // Hour of the day [00-23]
    ttm.tm_min = MM;
    ttm.tm_sec = SS;

    time_t ttime_t = mktime(&ttm);

    system_clock::time_point time_point_result = std::chrono::system_clock::from_time_t(ttime_t);

    time_point_result += std::chrono::milliseconds(fff);
    return time_point_result;
}

std::string time_point_to_string(std::chrono::system_clock::time_point &tp)
{
    using namespace std;
    using namespace std::chrono;

    auto ttime_t = system_clock::to_time_t(tp);
    auto tp_sec = system_clock::from_time_t(ttime_t);
    milliseconds ms = duration_cast<milliseconds>(tp - tp_sec);

    std::tm * ttm = localtime(&ttime_t);

    char date_time_format[] = "%Y.%m.%d-%H.%M.%S";

    char time_str[] = "yyyy.mm.dd.HH-MM.SS.fff";

    strftime(time_str, strlen(time_str), date_time_format, ttm);

    string result(time_str);
    result.append(".");
    result.append(to_string(ms.count()));

    return result;
}

"Port 4200 is already in use" when running the ng serve command

I also faced the same error msg, so i tried ng serve --port 12012 and it worked fine.

How to write multiple conditions of if-statement in Robot Framework

The below code worked fine:

Run Keyword if    '${value1}' \ \ == \ \ '${cost1}' \ and \ \ '${value2}' \ \ == \ \ 'cost2'    LOG    HELLO

how to install apk application from my pc to my mobile android

1) Put the apk on your SDKCard and install file browsers like "Estrongs File Explorer", "Easy Installer", etc...

https://market.android.com/details?id=com.estrongs.android.pop&feature=search_result https://market.android.com/details?id=mobi.infolife.installer&feature=search_result

2) Go to your mobile settings - applications- debuging - and thick "USB debugging" enter image description here

Use :hover to modify the css of another class?

There are two approaches you can take, to have a hovered element affect (E) another element (F):

  1. F is a child-element of E, or
  2. F is a later-sibling (or sibling's descendant) element of E (in that E appears in the mark-up/DOM before F):

To illustrate the first of these options (F as a descendant/child of E):

.item:hover .wrapper {
    color: #fff;
    background-color: #000;
}?

To demonstrate the second option, F being a sibling element of E:

.item:hover ~ .wrapper {
    color: #fff;
    background-color: #000;
}?

In this example, if .wrapper was an immediate sibling of .item (with no other elements between the two) you could also use .item:hover + .wrapper.

JS Fiddle demonstration.

References:

How do I install PHP cURL on Linux Debian?

Whatever approach you take, make sure in the end that you have an updated version of curl and libcurl. You can do curl --version and see the versions.

Here's what I did to get the latest curl version installed in Ubuntu:

  1. sudo add-apt-repository "deb http://mirrors.kernel.org/ubuntu wily main"
  2. sudo apt-get update
  3. sudo apt-get install curl

How to check String in response body with mockMvc

One possible approach is to simply include gson dependency:

<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
</dependency>

and parse the value to make your verifications:

@RunWith(SpringRunner.class)
@WebMvcTest(HelloController.class)
public class HelloControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @MockBean
    private HelloService helloService;

    @Before
    public void before() {
        Mockito.when(helloService.message()).thenReturn("hello world!");
    }

    @Test
    public void testMessage() throws Exception {
        MvcResult mvcResult = mockMvc.perform(MockMvcRequestBuilders.get("/"))
                .andExpect(status().isOk())
                .andExpect(content().contentTypeCompatibleWith(MediaType.APPLICATION_JSON_VALUE))
                .andReturn();

        String responseBody = mvcResult.getResponse().getContentAsString();
        ResponseDto responseDto
                = new Gson().fromJson(responseBody, ResponseDto.class);
        Assertions.assertThat(responseDto.message).isEqualTo("hello world!");
    }
}

How to pass a list from Python, by Jinja2 to JavaScript

I can suggest you a javascript oriented approach which makes it easy to work with javascript files in your project.

Create a javascript section in your jinja template file and place all variables you want to use in your javascript files in a window object:

Start.html

...
{% block scripts %}
<script type="text/javascript">
window.appConfig = {
    debug: {% if env == 'development' %}true{% else %}false{% endif %},
    facebook_app_id: {{ facebook_app_id }},
    accountkit_api_version: '{{ accountkit_api_version }}',
    csrf_token: '{{ csrf_token }}'
}
</script>
<script type="text/javascript" src="{{ url_for('static', filename='app.js') }}"></script>
{% endblock %}

Jinja will replace values and our appConfig object will be reachable from our other script files:

App.js

var AccountKit_OnInteractive = function(){
    AccountKit.init({
        appId: appConfig.facebook_app_id,
        debug: appConfig.debug,
        state: appConfig.csrf_token,
        version: appConfig.accountkit_api_version
    })
}

I have seperated javascript code from html documents with this way which is easier to manage and seo friendly.

How to assign text size in sp value using java code

This is code for the convert PX to SP format. 100% Works

view.setTextSize(TypedValue.COMPLEX_UNIT_PX, 24);

Formatting a field using ToText in a Crystal Reports formula field

if(isnull({uspRptMonthlyGasRevenueByGas;1.YearTotal})) = true then
   "nd"
else
    totext({uspRptMonthlyGasRevenueByGas;1.YearTotal},'###.00')

The above logic should be what you are looking for.

How to add element to C++ array?

You can use a variable to count places in the array, so when ever you add a new element, you put it in the right place. For example:

int a = 0;
int arr[5] = { };
arr[a] = 6;
a++;

Constants in Objective-C

Try using a class method:

+(NSString*)theMainTitle
{
    return @"Hello World";
}

I use it sometimes.

Wordpress - Images not showing up in the Media Library

I faced same issue on my wordpress site. After the lot of debugging i fixed my problem step by step like this.

  1. First add given below code your db-config.php
define('SCRIPT_DEBUG', TRUE);
define('WP_DEBUG', TRUE);
define( 'WP_DEBUG_LOG', true );
  1. Then goto /wp-includes/js/wp-util.js files and find the code $.ajax( options ) on line number 100 insert given below code into your file
deferred.jqXHR = $.ajax( options ).done( function( response ) {
  try {
      response = JSON.parse(response);
  } catch (Exception) {
      response = response;
  }

Please check your may be resolved.

  1. if you Removed constant from db-config.php
define('SCRIPT_DEBUG', TRUE);
define('WP_DEBUG', TRUE);
define( 'WP_DEBUG_LOG', true );   
  1. Then compress your /wp-includes/js/wp-util.js file code and put your compressed code into /wp-includes/js/wp-util.min.js

*change your own risk if your update your wordpress version your changed may be lost.

How do I force a DIV block to extend to the bottom of a page even if it has no content?

I think the issue would be fixed just making the html fill 100% also, might be body fills the 100% of the html but html doesn't fill 100% of the screen.

Try with:

html, body {
      height: 100%;
}

how to check if object already exists in a list

If you use EF core add

 .UseSerialColumn();

Example

modelBuilder.Entity<JobItem>(entity =>
        {
            entity.ToTable("jobs");

            entity.Property(e => e.Id)
                .HasColumnName("id")
                .UseSerialColumn();
});

How are software license keys generated?

There are also DRM behaviors that incorporate multiple steps to the process. One of the most well known examples is one of Adobe's methods for verifying an installation of their Creative Suite. The traditional CD Key method discussed here is used, then Adobe's support line is called. The CD key is given to the Adobe representative and they give back an activation number to be used by the user.

However, despite being broken up into steps, this falls prey to the same methods of cracking used for the normal process. The process used to create an activation key that is checked against the original CD key was quickly discovered, and generators that incorporate both of the keys were made.

However, this method still exists as a way for users with no internet connection to verify the product. Going forward, it's easy to see how these methods would be eliminated as internet access becomes ubiquitous.

Create, read, and erase cookies with jQuery

Use jquery cookie plugin, the link as working today: https://github.com/js-cookie/js-cookie

How to add style from code behind?

You can't.

So just don't apply styles directly like that, and apply a class "foo", and then define that in your CSS specification:

a.foo { color : orange; }
a.foo:hover { font-weight : bold; }

.NET Core vs Mono

.Net Core does not require mono in the sense of the mono framework. .Net Core is a framework that will work on multiple platforms including Linux. Reference https://dotnet.github.io/.

However the .Net core can use the mono framework. Reference https://docs.asp.net/en/1.0.0-rc1/getting-started/choosing-the-right-dotnet.html (note rc1 documentatiopn no rc2 available), however mono is not a Microsoft supported framework and would recommend using a supported framework

Now entity framework 7 is now called Entity Framework Core and is available on multiple platforms including Linux. Reference https://github.com/aspnet/EntityFramework (review the road map)

I am currently using both of these frameworks however you must understand that it is still in release candidate stage (RC2 is the current version) and over the beta & release candidates there have been massive changes that usually end up with you scratching your head.

Here is a tutorial on how to install MVC .Net Core into Linux. https://docs.asp.net/en/1.0.0-rc1/getting-started/installing-on-linux.html

Finally you have a choice of Web Servers (where I am assuming the fast cgi reference came from) to host your application on Linux. Here is a reference point for installing to a Linux enviroment. https://docs.asp.net/en/1.0.0-rc1/publishing/linuxproduction.html

I realise this post ends up being mostly links to documentation but at this point those are your best sources of information. .Net core is still relatively new in the .Net community and until its fully released I would be hesitant to use it in a product environment given the breaking changes between released version.

Warning: DOMDocument::loadHTML(): htmlParseEntityRef: expecting ';' in Entity,

Regardless of the echo (which would need to be replaced with print_r or var_dump), if an exception is thrown the object should stay empty:

DOMNodeList Object
(
)

Solution

  1. Set recover to true, and strictErrorChecking to false

    $content = file_get_contents($url);
    
    $doc = new DOMDocument();
    $doc->recover = true;
    $doc->strictErrorChecking = false;
    $doc->loadHTML($content);
    
  2. Use php's entity-encoding on the markup's contents, which is a most common error source.

server error:405 - HTTP verb used to access this page is not allowed

I fixed mine by adding these lines on my IIS webconfig.

<httpErrors>
    <remove statusCode="405" subStatusCode="-1" />
    <error statusCode="405" prefixLanguageFilePath="" path="/my-page.htm" responseMode="ExecuteURL" />
</httpErrors>

How to open a Bootstrap modal window using jQuery?

Try

$("#myModal").modal("toggle")

To open or close the modal with id myModal.

If the above is not working then it means bootstrap.js has been overridden by some other js file. Here is a solution

1:- Move bootstrap.js to the bottom so that it will override other js files.

2:- Make sure the order is like below

<script src="plugins/jQuery/jquery-2.2.3.min.js"></script>
<!-- Other js files -->
<script src="plugins/jQuery/bootstrap.min.js"></script>

Composer install error - requires ext_curl when it's actually enabled

I ran into a similar issue when trying to get composer to install some dependencies. It turns out the .dll my version of Wamp came with had a conflict, I am guessing, with 64 bit Windows.

This url has fixed curl dlls: http://www.anindya.com/php-5-4-3-and-php-5-3-13-x64-64-bit-for-windows/

Scroll down to the section that says: Fixed Curl Extensions.

I downloaded "php_curl-5.4.3-VC9-x64.zip". I just overwrote the dll inside the wamp/bin/php/php5.4.3/ext directory with the dll that was in the zip file and composer worked again.

I am running 64 bit Windows 8.

Hope this helps.

Jquery find nearest matching element

closest() only looks for parents, I'm guessing what you really want is .find()

$(this).closest('.row').children('.column').find('.inputQty').val();

The default XML namespace of the project must be the MSBuild XML namespace

if the project is not a big ,

1- change the name of folder project

2- make a new project with the same project (before renaming)

3- add existing files from the old project to the new project (totally same , same folders , same names , ...)

4- open the the new project file (as xml ) and the old project

5- copy the new project file (xml content ) and paste it in the old project file

6- delete the old project

7- rename the old folder project to old name

Private vs Protected - Visibility Good-Practice Concern

Stop abusing private fields!!!

The comments here seem to be overwhelmingly supportive towards using private fields. Well, then I have something different to say.

Are private fields good in principle? Yes. But saying that a golden rule is make everything private when you're not sure is definitely wrong! You won't see the problem until you run into one. In my opinion, you should mark fields as protected if you're not sure.

There are two cases you want to extend a class:

  • You want to add extra functionality to a base class
  • You want to modify existing class that's outside the current package (in some libraries perhaps)

There's nothing wrong with private fields in the first case. The fact that people are abusing private fields makes it so frustrating when you find out you can't modify shit.

Consider a simple library that models cars:

class Car {
    private screw;
    public assembleCar() {
       screw.install();
    };
    private putScrewsTogether() {
       ...
    };
}

The library author thought: there's no reason the users of my library need to access the implementation detail of assembleCar() right? Let's mark screw as private.

Well, the author is wrong. If you want to modify only the assembleCar() method without copying the whole class into your package, you're out of luck. You have to rewrite your own screw field. Let's say this car uses a dozen of screws, and each of them involves some untrivial initialization code in different private methods, and these screws are all marked private. At this point, it starts to suck.

Yes, you can argue with me that well the library author could have written better code so there's nothing wrong with private fields. I'm not arguing that private field is a problem with OOP. It is a problem when people are using them.

The moral of the story is, if you're writing a library, you never know if your users want to access a particular field. If you're unsure, mark it protected so everyone would be happier later. At least don't abuse private field.

I very much support Nick's answer.

Create SQLite Database and table

The next link will bring you to a great tutorial, that helped me a lot!

How to SQLITE in C#

I nearly used everything in that article to create the SQLite database for my own C# Application.

Don't forget to download the SQLite.dll, and add it as a reference to your project. This can be done using NuGet and by adding the dll manually.

After you added the reference, refer to the dll from your code using the following line on top of your class:

using System.Data.SQLite;

You can find the dll's here:

SQLite DLL's

You can find the NuGet way here:

NuGet

Up next is the create script. Creating a database file:

SQLiteConnection.CreateFile("MyDatabase.sqlite");

SQLiteConnection m_dbConnection = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;");
m_dbConnection.Open();

string sql = "create table highscores (name varchar(20), score int)";

SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
command.ExecuteNonQuery();

sql = "insert into highscores (name, score) values ('Me', 9001)";

command = new SQLiteCommand(sql, m_dbConnection);
command.ExecuteNonQuery();

m_dbConnection.Close();

After you created a create script in C#, I think you might want to add rollback transactions, it is safer and it will keep your database from failing, because the data will be committed at the end in one big piece as an atomic operation to the database and not in little pieces, where it could fail at 5th of 10 queries for example.

Example on how to use transactions:

 using (TransactionScope tran = new TransactionScope())
 {
     //Insert create script here.

     //Indicates that creating the SQLiteDatabase went succesfully, so the database can be committed.
     tran.Complete();
 }

How to enable CORS in apache tomcat

Check this answer: Set CORS header in Tomcat

Note that you need Tomcat 7.0.41 or higher.

To know where the current instance of Tomcat is located try this:

System.out.println(System.getProperty("catalina.base"));

You'll see the path in the console view.

Then look for /conf/web.xml on that folder, open it and add the lines of the above link.

jQuery attr() change img src

You remove the original image here:

newImg.animate(css, SPEED, function() {
    img.remove();
    newImg.removeClass('morpher');
    (callback || function() {})();
});

And all that's left behind is newImg. Then you reset link references the image using #rocket:

$("#rocket").attr('src', ...

But your newImg doesn't have an id attribute let alone an id of rocket.

To fix this, you need to remove img and then set the id attribute of newImg to rocket:

newImg.animate(css, SPEED, function() {
    var old_id = img.attr('id');
    img.remove();
    newImg.attr('id', old_id);
    newImg.removeClass('morpher');
    (callback || function() {})();
});

And then you'll get the shiny black rocket back again: http://jsfiddle.net/ambiguous/W2K9D/

UPDATE: A better approach (as noted by mellamokb) would be to hide the original image and then show it again when you hit the reset button. First, change the reset action to something like this:

$("#resetlink").click(function(){
    clearInterval(timerRocket);
    $("#wrapper").css('top', '250px');
    $('.throbber, .morpher').remove(); // Clear out the new stuff.
    $("#rocket").show();               // Bring the original back.
});

And in the newImg.load function, grab the images original size:

var orig = {
    width: img.width(),
    height: img.height()
};

And finally, the callback for finishing the morphing animation becomes this:

newImg.animate(css, SPEED, function() {
    img.css(orig).hide();
    (callback || function() {})();
});

New and improved: http://jsfiddle.net/ambiguous/W2K9D/1/

The leaking of $('.throbber, .morpher') outside the plugin isn't the best thing ever but it isn't a big deal as long as it is documented.

How to convert a python numpy array to an RGB image with Opencv 2.4?

The images c, d, e , and f in the following show colorspace conversion they also happen to be numpy arrays <type 'numpy.ndarray'>:

import numpy, cv2
def show_pic(p):
        ''' use esc to see the results'''
        print(type(p))
        cv2.imshow('Color image', p)
        while True:
            k = cv2.waitKey(0) & 0xFF
            if k == 27: break 
        return
        cv2.destroyAllWindows()

b = numpy.zeros([200,200,3])

b[:,:,0] = numpy.ones([200,200])*255
b[:,:,1] = numpy.ones([200,200])*255
b[:,:,2] = numpy.ones([200,200])*0
cv2.imwrite('color_img.jpg', b)


c = cv2.imread('color_img.jpg', 1)
c = cv2.cvtColor(c, cv2.COLOR_BGR2RGB)

d = cv2.imread('color_img.jpg', 1)
d = cv2.cvtColor(c, cv2.COLOR_RGB2BGR)

e = cv2.imread('color_img.jpg', -1)
e = cv2.cvtColor(c, cv2.COLOR_BGR2RGB)

f = cv2.imread('color_img.jpg', -1)
f = cv2.cvtColor(c, cv2.COLOR_RGB2BGR)


pictures = [d, c, f, e]

for p in pictures:
        show_pic(p)
# show the matrix
print(c)
print(c.shape)

See here for more info: http://docs.opencv.org/modules/imgproc/doc/miscellaneous_transformations.html#cvtcolor

OR you could:

img = numpy.zeros([200,200,3])

img[:,:,0] = numpy.ones([200,200])*255
img[:,:,1] = numpy.ones([200,200])*255
img[:,:,2] = numpy.ones([200,200])*0

r,g,b = cv2.split(img)
img_bgr = cv2.merge([b,g,r])

LOAD DATA INFILE Error Code : 13

for Ubuntu users

I'm running mysql 5.6.28 on Ubuntu 15.10 and I just ran into the exact same problem, I had all the necessary flags in my.cnf tmpdir = /tmp local-infile=1 restarted mysql and I would still get LOAD DATA INFILE Error Code : 13

Just like Nelson mentionned the issue was "apparmor", sort of patronising mysql about permissions, I then found the solution thanks to this quick & easy tutorial.

basically, assuming your tmp dir would be /tmp :

Add new tmpdir entries to /etc/apparmor.d/local/usr.sbin.mysqld

sudo nano /etc/apparmor.d/local/usr.sbin.mysqld

*add this

/tmp/ r,
/mnt/foo/tmp/** rw,

Reload AppArmor

sudo service apparmor reload

Restart MySQL

sudo service mysql restart

I hope that'll help few Ubuntu-ers

Append a single character to a string or char array in java?

First of all you use here two strings: "" marks a string it may be ""-empty "s"- string of lenght 1 or "aaa" string of lenght 3, while '' marks chars . In order to be able to do String str = "a" + "aaa" + 'a' you must use method Character.toString(char c) as @Thomas Keene said so an example would be String str = "a" + "aaa" + Character.toString('a')

Differences between C++ string == and compare()?

One thing that is not covered here is that it depends if we compare string to c string, c string to string or string to string.

A major difference is that for comparing two strings size equality is checked before doing the compare and that makes the == operator faster than a compare.

here is the compare as i see it on g++ Debian 7

// operator ==
  /**
   *  @brief  Test equivalence of two strings.
   *  @param __lhs  First string.
   *  @param __rhs  Second string.
   *  @return  True if @a __lhs.compare(@a __rhs) == 0.  False otherwise.
   */
  template<typename _CharT, typename _Traits, typename _Alloc>
    inline bool
    operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
           const basic_string<_CharT, _Traits, _Alloc>& __rhs)
    { return __lhs.compare(__rhs) == 0; }

  template<typename _CharT>
    inline
    typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, bool>::__type
    operator==(const basic_string<_CharT>& __lhs,
           const basic_string<_CharT>& __rhs)
    { return (__lhs.size() == __rhs.size()
          && !std::char_traits<_CharT>::compare(__lhs.data(), __rhs.data(),
                            __lhs.size())); }

  /**
   *  @brief  Test equivalence of C string and string.
   *  @param __lhs  C string.
   *  @param __rhs  String.
   *  @return  True if @a __rhs.compare(@a __lhs) == 0.  False otherwise.
   */
  template<typename _CharT, typename _Traits, typename _Alloc>
    inline bool
    operator==(const _CharT* __lhs,
           const basic_string<_CharT, _Traits, _Alloc>& __rhs)
    { return __rhs.compare(__lhs) == 0; }

  /**
   *  @brief  Test equivalence of string and C string.
   *  @param __lhs  String.
   *  @param __rhs  C string.
   *  @return  True if @a __lhs.compare(@a __rhs) == 0.  False otherwise.
   */
  template<typename _CharT, typename _Traits, typename _Alloc>
    inline bool
    operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
           const _CharT* __rhs)
    { return __lhs.compare(__rhs) == 0; }

Using SSH keys inside docker container

You can use multi stage build to build containers This is the approach you can take :-

Stage 1 building an image with ssh

FROM ubuntu as sshImage
LABEL stage=sshImage
ARG SSH_PRIVATE_KEY
WORKDIR /root/temp

RUN apt-get update && \
    apt-get install -y git npm 

RUN mkdir /root/.ssh/ &&\
    echo "${SSH_PRIVATE_KEY}" > /root/.ssh/id_rsa &&\
    chmod 600 /root/.ssh/id_rsa &&\
    touch /root/.ssh/known_hosts &&\
    ssh-keyscan github.com >> /root/.ssh/known_hosts

COPY package*.json ./

RUN npm install

RUN cp -R node_modules prod_node_modules

Stage 2: build your container

FROM node:10-alpine

RUN mkdir -p /usr/app

WORKDIR /usr/app

COPY ./ ./

COPY --from=sshImage /root/temp/prod_node_modules ./node_modules

EXPOSE 3006

CMD ["npm", "run", "dev"] 

add env attribute in your compose file:

   environment:
      - SSH_PRIVATE_KEY=${SSH_PRIVATE_KEY}

then pass args from build script like this:

docker-compose build --build-arg SSH_PRIVATE_KEY="$(cat ~/.ssh/id_rsa)"

And remove the intermediate container it for security. This Will help you cheers.

XAMPP - Apache could not start - Attempting to start Apache service

For those who have accidentally (or not) changed one of the .conf files and apache does not run even after trying all the above solutions.

One easy way to track where the issue is located, is to run Apache via command prompt:

(On windows) : open command prompt as admin then navigate inside the bin folder of Apache , next run

httpd in order to run apache

C:\xampp\apache\bin\httpd

For my case it was :

apache via cmd

someone had added a virtual host in the specific file that caused the problem . I commented the lines and Apache ran fine.

Find and Replace text in the entire table using a MySQL query

 UPDATE table SET field = replace(field, text_needs_to_be_replaced, text_required);

Like for example, if I want to replace all occurrences of John by Mark I will use below,

UPDATE student SET student_name = replace(student_name, 'John', 'Mark');

Use success() or complete() in AJAX call

complete executes after either the success or error callback were executed.

Maybe you should check the second parameter complete offers too. It's a String holding the type of success the ajaxCall had.

The different callbacks are described a little more in detail here jQuery.ajax( options )


I guess you missed the fact that the complete and the success function (I know inconsistent API) get different data passed in. success gets only the data, complete gets the whole XMLHttpRequest object. Of course there is no responseText property on the data string.

So if you replace complete with success you also have to replace data.responseText with data only.

success

The function gets passed two arguments: The data returned from the server, formatted according to the 'dataType' parameter, and a string describing the status.

complete

The function gets passed two arguments: The XMLHttpRequest object and a string describing the type of success of the request.

If you need to have access to the whole XMLHttpRequest object in the success callback I suggest trying this.

var myXHR = $.ajax({
    ...
    success: function(data, status) {
        ...do whatever with myXHR; e.g. myXHR.responseText...
    },
    ...
});

Return the most recent record from ElasticSearch index

Get the Last ID using by date (with out time stamp)

Sample URL : http://localhost:9200/deal/dealsdetails/
Method : POST

Query :

{
  "fields": ["_id"],
  "sort": [{
      "created_date": {
        "order": "desc"
      }
    },
    {
      "_score": {
        "order": "desc"
      }
    }
  ],
  "size": 1
}

result:

{
  "took": 4,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 9,
    "max_score": null,
    "hits": [{
      "_index": "deal",
      "_type": "dealsdetails",
      "_id": "10",
      "_score": 1,
      "sort": [
        1478266145174,
        1
      ]
    }]
  }
}

Detect if a page has a vertical scrollbar?

try this:

var hasVScroll = document.body.scrollHeight > document.body.clientHeight;

This will only tell you if the vertical scrollHeight is bigger than the height of the viewable content, however. The hasVScroll variable will contain true or false.

If you need to do a more thorough check, add the following to the code above:

// Get the computed style of the body element
var cStyle = document.body.currentStyle||window.getComputedStyle(document.body, "");

// Check the overflow and overflowY properties for "auto" and "visible" values
hasVScroll = cStyle.overflow == "visible" 
             || cStyle.overflowY == "visible"
             || (hasVScroll && cStyle.overflow == "auto")
             || (hasVScroll && cStyle.overflowY == "auto");

Difference between decimal, float and double in .NET?

The Decimal structure is strictly geared to financial calculations requiring accuracy, which are relatively intolerant of rounding. Decimals are not adequate for scientific applications, however, for several reasons:

  • A certain loss of precision is acceptable in many scientific calculations because of the practical limits of the physical problem or artifact being measured. Loss of precision is not acceptable in finance.
  • Decimal is much (much) slower than float and double for most operations, primarily because floating point operations are done in binary, whereas Decimal stuff is done in base 10 (i.e. floats and doubles are handled by the FPU hardware, such as MMX/SSE, whereas decimals are calculated in software).
  • Decimal has an unacceptably smaller value range than double, despite the fact that it supports more digits of precision. Therefore, Decimal can't be used to represent many scientific values.

Print to the same line and not a new line?

This works for me, hacked it once to see if it is possible, but never actually used in my program (GUI is so much nicer):

import time
f = '%4i %%'
len_to_clear = len(f)+1
clear = '\x08'* len_to_clear
print 'Progress in percent:'+' '*(len_to_clear),
for i in range(123):
    print clear+f % (i*100//123),
    time.sleep(0.4)
raw_input('\nDone')

Difference between static class and singleton pattern?

Well a singleton is just a normal class that IS instantiated but just once and indirectly from the client code. Static class is not instantiated. As far as I know static methods (static class must have static methods) are faster than non-static.

Edit:
FxCop Performance rule description: "Methods which do not access instance data or call instance methods can be marked as static (Shared in VB). After doing so, the compiler will emit non-virtual call sites to these members which will prevent a check at runtime for each call that insures the current object pointer is non-null. This can result in a measurable performance gain for performance-sensitive code. In some cases, the failure to access the current object instance represents a correctness issue."
I don't actually know if this applies also to static methods in static classes.

How to empty ("truncate") a file on linux that already exists and is protected in someway?

You have the noclobber option set. The error looks like it's from csh, so you would do:

cat /dev/null >! file

If I'm wrong and you are using bash, you should do:

cat /dev/null >| file

in bash, you can also shorten that to:

>| file

CSS: Hover one element, effect for multiple elements?

You'd need to use JavaScript to accomplish this, I think.

jQuery:

$(function(){
   $("#innerContainer").hover(
        function(){
            $("#innerContainer").css('border-color','#FFF');
            $("#outerContainer").css('border-color','#FFF');
        },
        function(){
            $("#innerContainer").css('border-color','#000');
            $("#outerContainer").css('border-color','#000');
        }
    );
});

Adjust the values and element id's accordingly :)

How do you specify table padding in CSS? ( table, not cell padding )

You could set a margin for the table. Alternatively, wrap the table in a div and use the div's padding.

Accessing bash command line args $@ vs $*

The difference appears when the special parameters are quoted. Let me illustrate the differences:

$ set -- "arg  1" "arg  2" "arg  3"

$ for word in $*; do echo "$word"; done
arg
1
arg
2
arg
3

$ for word in $@; do echo "$word"; done
arg
1
arg
2
arg
3

$ for word in "$*"; do echo "$word"; done
arg  1 arg  2 arg  3

$ for word in "$@"; do echo "$word"; done
arg  1
arg  2
arg  3

one further example on the importance of quoting: note there are 2 spaces between "arg" and the number, but if I fail to quote $word:

$ for word in "$@"; do echo $word; done
arg 1
arg 2
arg 3

and in bash, "$@" is the "default" list to iterate over:

$ for word; do echo "$word"; done
arg  1
arg  2
arg  3

CSS3 transition on click using pure CSS

Voila!

_x000D_
_x000D_
div {_x000D_
  background-color: red;_x000D_
  color: white;_x000D_
  font-weight: bold;_x000D_
  width: 48px;_x000D_
  height: 48px;  _x000D_
  transform: rotate(360deg);_x000D_
  transition: transform 0.5s;_x000D_
}_x000D_
_x000D_
div:active {_x000D_
  transform: rotate(0deg);_x000D_
  transition:  0s;_x000D_
}
_x000D_
<div></div>
_x000D_
_x000D_
_x000D_

Tomcat: How to find out running tomcat version

Windows task manager > Processes > find tomcat > right click > open file location > if you run Tomcat7w.exe it is visible at description.

Tomcat should running to be visible at Processes if not at Windows Vista/7 go to task manager > tab (services) find tomcat start it and then processes.

How to use group by with union in t-sql

You need to alias the subquery. Thus, your statement should be:

Select Z.id
From    (
        Select id, time
        From dbo.tablea
        Union All
        Select id, time
        From dbo.tableb
        ) As Z
Group By Z.id

Parsing XML with namespace in Python via 'ElementTree'

ElementTree is not too smart about namespaces. You need to give the .find(), findall() and iterfind() methods an explicit namespace dictionary. This is not documented very well:

namespaces = {'owl': 'http://www.w3.org/2002/07/owl#'} # add more as needed

root.findall('owl:Class', namespaces)

Prefixes are only looked up in the namespaces parameter you pass in. This means you can use any namespace prefix you like; the API splits off the owl: part, looks up the corresponding namespace URL in the namespaces dictionary, then changes the search to look for the XPath expression {http://www.w3.org/2002/07/owl}Class instead. You can use the same syntax yourself too of course:

root.findall('{http://www.w3.org/2002/07/owl#}Class')

If you can switch to the lxml library things are better; that library supports the same ElementTree API, but collects namespaces for you in a .nsmap attribute on elements.

PHP: How do I display the contents of a textfile on my page?

if you just want to show the file itself:

header('Content-Type: text/plain');
header('Content-Disposition: inline; filename="filename.txt"');
readfile(path);

Measuring text height to be drawn on Canvas ( Android )

You can simply get the text size for a Paint object using getTextSize() method. For example:

Paint mTextPaint = new Paint (Paint.ANTI_ALIAS_FLAG);
//use densityMultiplier to take into account different pixel densities
final float densityMultiplier = getContext().getResources()
            .getDisplayMetrics().density;  
mTextPaint.setTextSize(24.0f*densityMultiplier);

//...

float size = mTextPaint.getTextSize();

How to set JVM parameters for Junit Unit Tests?

If you set it in Java code, you can set it like this

      static {
        System.getProperties().setProperty("env", "test");
        System.getProperties().setProperty("spring.application.name", "spring-example");
    }

reference:

https://stackoverflow.com/a/60654275/4712855

https://stackoverflow.com/a/10774432/4712855

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

Output on Windows 7 (64-bit)

SpecialFolder.CommonApplicationData: C:\ProgramData 
SpecialFolder.CommonDesktopDirectory: C:\Users\Public\Desktop
SpecialFolder.CommonStartMenu: C:\ProgramData\Microsoft\Windows\Start Menu
SpecialFolder.CommonPrograms: C:\ProgramData\Microsoft\Windows\Start Menu\Programs
SpecialFolder.CommonProgramFiles: C:\Program Files\Common Files
SpecialFolder.CommonProgramFilesX86: C:\Program Files (x86)\Common Files
SpecialFolder.CommonStartup: C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup
SpecialFolder.ProgramFiles: C:\Program Files
SpecialFolder.ProgramFilesX86: C:\Program Files (x86)
SpecialFolder.System: C:\Windows\system32
SpecialFolder.SystemX86: C:\Windows\SysWOW64

Output on Windows XP

SpecialFolder.CommonApplicationData: C:\Documents and Settings\All Users\Application Data
SpecialFolder.CommonDesktopDirectory: C:\Documents and Settings\All Users\Desktop
SpecialFolder.CommonPrograms: C:\Documents and Settings\All Users\Start Menu\Programs
SpecialFolder.CommonProgramFiles: C:\Program Files\Common Files
SpecialFolder.CommonProgramFilesX86:
SpecialFolder.CommonStartMenu: C:\Documents and Settings\All Users\Start Menu
SpecialFolder.CommonStartup: C:\Documents and Settings\All Users\Start Menu\Programs\Startup
SpecialFolder.ProgramFiles: C:\Program Files
SpecialFolder.ProgramFilesX86:
SpecialFolder.System: C:\WINDOWS\system32
SpecialFolder.SystemX86: C:\WINDOWS\system32

Get JSONArray without array name?

I've assumed a named JSONArray is a JSONObject and accessed the data from the server to populate an Android GridView. For what it is worth my method is:

private String[] fillTable( JSONObject jsonObject ) {
   String[] dummyData = new String[] {"1", "2", "3", "4", "5", "6", "7","1", "2", "3", "4", "5", "6", "7","1", "2", "3", "4", "5", "6", "7", };
  if( jsonObject != null ) {
      ArrayList<String> data = new ArrayList<String>();
      try {
          // jsonArray looks like { "everything" : [{}, {},] }
          JSONArray jsonArray = jsonObject.getJSONArray( "everything" );
          int number = jsonArray.length(); //How many rows have got from the database?
          Log.i( Constants.INFORMATION, "Number of ows returned:  " + Integer.toString( number ) );
                  // Array elements look like this
          //{"success":1,"error":0,"name":"English One","owner":"Tutor","description":"Initial Alert","posted":"2013-08-09 15:35:40"}
          for( int element = 0; element < number; element++ ) { //visit each element
             JSONObject jsonObject_local = jsonArray.getJSONObject( element );
             //  Overkill on the error/success checking
             Log.e("JSON SUCCESS", Integer.toString( jsonObject_local.getInt(Constants.KEY_SUCCESS) ) );
             Log.e("JSON ERROR", Integer.toString( jsonObject_local.getInt(Constants.KEY_ERROR) ) );
                if ( jsonObject_local.getInt( Constants.KEY_SUCCESS) == Constants.JSON_SUCCESS ) {
                   String name = jsonObject_local.getString( Constants.KEY_NAME );
                   data.add( name );
                   String owner = jsonObject_local.getString( Constants.KEY_OWNER );
                   data.add( owner );
                   String description = jsonObject_local.getString( Constants.KEY_DESCRIPTION );
                   Log.i( "DESCRIPTION", description );
                   data.add( description ); 
                   String date = jsonObject_local.getString( Constants.KEY_DATE );
                   data.add( date );
                }
                else {
                    for( int i = 0; i < 4; i++ ) {
                        data.add( "ERROR" );
                    }
                }
          }
  }  //JSON object is null
  catch ( JSONException jsone) {
      Log.e( "JSON EXCEPTION", jsone.getMessage() );
  }
      dummyData = data.toArray( dummyData );
  }
  return dummyData;

}

C library function to perform sort

I think you are looking for qsort.
qsort function is the implementation of quicksort algorithm found in stdlib.h in C/C++.

Here is the syntax to call qsort function:

void qsort(void *base, size_t nmemb, size_t size,int (*compar)(const void *, const void *));

List of arguments:

base: pointer to the first element or base address of the array
nmemb: number of elements in the array
size: size in bytes of each element
compar: a function that compares two elements

Here is a code example which uses qsort to sort an array:

#include <stdio.h>
#include <stdlib.h>

int arr[] = { 33, 12, 6, 2, 76 };

// compare function, compares two elements
int compare (const void * num1, const void * num2) {
   if(*(int*)num1 > *(int*)num2)
    return 1;
   else
    return -1;
}

int main () {
   int i;

   printf("Before sorting the array: \n");
   for( i = 0 ; i < 5; i++ ) {
      printf("%d ", arr[i]);
   }
   // calling qsort
   qsort(arr, 5, sizeof(int), compare);

   printf("\nAfter sorting the array: \n");
   for( i = 0 ; i < 5; i++ ) {   
      printf("%d ", arr[i]);
   }
  
   return 0;
}

You can type man 3 qsort in Linux/Mac terminal to get a detailed info about qsort.
Link to qsort man page

Create array of all integers between two numbers, inclusive, in Javascript/jQuery

ES6 :

Use Array.from (docs here):

_x000D_
_x000D_
console.log(
   Array.from({length:5},(v,k)=>k+1)
)
_x000D_
_x000D_
_x000D_

Firing a Keyboard Event in Safari, using JavaScript

Did you dispatch the event correctly?

function simulateKeyEvent(character) {
  var evt = document.createEvent("KeyboardEvent");
  (evt.initKeyEvent || evt.initKeyboardEvent)("keypress", true, true, window,
                    0, 0, 0, 0,
                    0, character.charCodeAt(0)) 
  var canceled = !body.dispatchEvent(evt);
  if(canceled) {
    // A handler called preventDefault
    alert("canceled");
  } else {
    // None of the handlers called preventDefault
    alert("not canceled");
  }
}

If you use jQuery, you could do:

function simulateKeyPress(character) {
  jQuery.event.trigger({ type : 'keypress', which : character.charCodeAt(0) });
}

How does one output bold text in Bash?

In theory like so:

# BOLD
$ echo -e "\033[1mThis is a BOLD line\033[0m"
This is a BOLD line

# Using tput
tput bold 
echo "This" #BOLD
tput sgr0 #Reset text attributes to normal without clear.
echo "This" #NORMAL

# UNDERLINE
$ echo -e "\033[4mThis is a underlined line.\033[0m"
This is a underlined line. 

But in practice it may be interpreted as "high intensity" color instead.

(source: http://unstableme.blogspot.com/2008/01/ansi-escape-sequences-for-writing-text.html)

Regex: Use start of line/end of line signs (^ or $) in different context

You can't use ^ and $ in character classes in the way you wish - they will be interpreted literally, but you can use an alternation to achieve the same effect:

(^|,)garp(,|$)

Unsupported operation :not writeable python

file = open('ValidEmails.txt','wb')
file.write(email.encode('utf-8', 'ignore'))

This is solve your encode error also.

how to make a new line in a jupyter markdown cell

"We usually put ' (space)' after the first sentence before a new line, but it doesn't work in Jupyter."

That inspired me to try using two spaces instead of just one - and it worked!!

(Of course, that functionality could possibly have been introduced between when the question was asked in January 2017, and when my answer was posted in March 2018.)

How to prevent IFRAME from redirecting top-level window

Try using the onbeforeunload property, which will let the user choose whether he wants to navigate away from the page.

Example: https://developer.mozilla.org/en-US/docs/Web/API/Window.onbeforeunload

In HTML5 you can use sandbox property. Please see Pankrat's answer below. http://www.html5rocks.com/en/tutorials/security/sandboxed-iframes/

XmlWriter to Write to a String Instead of to a File

Guys don't forget to call xmlWriter.Close() and xmlWriter.Dispose() or else your string won't finish creating. It will just be an empty string

Python string prints as [u'String']

import json, ast
r = {u'name': u'A', u'primary_key': 1}
ast.literal_eval(json.dumps(r)) 

will print

{'name': 'A', 'primary_key': 1}

How to generate keyboard events?

regarding the recommended answer's code,

For my bot the recommended answer did not work. This is because I'm using Chrome which is requiring me to use KEYEVENTF_SCANCODE in my dwFlags.

To get his code to work I had to modify these code blocks:

class KEYBDINPUT(ctypes.Structure):
    _fields_ = (("wVk",         wintypes.WORD),
                ("wScan",       wintypes.WORD),
                ("dwFlags",     wintypes.DWORD),
                ("time",        wintypes.DWORD),
                ("dwExtraInfo", wintypes.ULONG_PTR))

    def __init__(self, *args, **kwds):
        super(KEYBDINPUT, self).__init__(*args, **kwds)
        # some programs use the scan code even if KEYEVENTF_SCANCODE
        # isn't set in dwFflags, so attempt to map the correct code.
        #if not self.dwFlags & KEYEVENTF_UNICODE:l
            #self.wScan = user32.MapVirtualKeyExW(self.wVk,
                                                 #MAPVK_VK_TO_VSC, 0)
            # ^MAKE SURE YOU COMMENT/REMOVE THIS CODE^

def PressKey(keyCode):
    input = INPUT(type=INPUT_KEYBOARD,
              ki=KEYBDINPUT(wScan=keyCode,
                            dwFlags=KEYEVENTF_SCANCODE))
    user32.SendInput(1, ctypes.byref(input), ctypes.sizeof(input))

def ReleaseKey(keyCode):
    input = INPUT(type=INPUT_KEYBOARD,
              ki=KEYBDINPUT(wScan=keyCode,
                            dwFlags=KEYEVENTF_SCANCODE | KEYEVENTF_KEYUP))
    user32.SendInput(1, ctypes.byref(input), ctypes.sizeof(input))

time.sleep(5) # sleep to open browser tab
PressKey(0x26) # press right arrow key
time.sleep(2) # hold for 2 seconds
ReleaseKey(0x26) # release right arrow key

I hope this helps someone's headache!

What does if [ $? -eq 0 ] mean for shell scripts?

$? is the exit status of the most recently-executed command; by convention, 0 means success and anything else indicates failure. That line is testing whether the grep command succeeded.

The grep manpage states:

The exit status is 0 if selected lines are found, and 1 if not found. If an error occurred the exit status is 2. (Note: POSIX error handling code should check for '2' or greater.)

So in this case it's checking whether any ERROR lines were found.

Import-Module : The specified module 'activedirectory' was not loaded because no valid module file was found in any module directory

This may be an old post, but if anyone is still facing this issue after trying all the above mentioned steps, ensure whether the default path of PowerShell module is specified under the "PSModulePath" environment variable.

The default path should be "%SystemRoot%\system32\WindowsPowerShell\v1.0\Modules\"

MySql with JAVA error. The last packet sent successfully to the server was 0 milliseconds ago

The problem is mostly due to a MySQL service that is not running, so make sure it is. If it isn't, run this CMD with administrator privilege in order to start it:

sc start [Your MySQL Service name]

How to split a string by spaces in a Windows batch file?

see HELP FOR and see the examples

or quick try this

 for /F %%a in ("AAA BBB CCC DDD EEE FFF") do echo %%c

How to test multiple variables against a value?

If you ARE very very lazy, you can put the values inside an array. Such as

list = []
list.append(x)
list.append(y)
list.append(z)
nums = [add numbers here]
letters = [add corresponding letters here]
for index in range(len(nums)):
    for obj in list:
        if obj == num[index]:
            MyList.append(letters[index])
            break

You can also put the numbers and letters in a dictionary and do it, but this is probably a LOT more complicated than simply if statements. That's what you get for trying to be extra lazy :)

One more thing, your

if x or y or z == 0:

will compile, but not in the way you want it to. When you simply put a variable in an if statement (example)

if b

the program will check if the variable is not null. Another way to write the above statement (which makes more sense) is

if bool(b)

Bool is an inbuilt function in python which basically does the command of verifying a boolean statement (If you don't know what that is, it is what you are trying to make in your if statement right now :))

Another lazy way I found is :

if any([x==0, y==0, z==0])

What is the meaning of @_ in Perl?

Usually, you expand the parameters passed to a sub using the @_ variable:

sub test{
  my ($a, $b, $c) = @_;
  ...
}

# call the test sub with the parameters
test('alice', 'bob', 'charlie');

That's the way claimed to be correct by perlcritic.

Does IMDB provide an API?

Here is a simple solution that fetches shows by name based on the query from Krinkle:

You can get around the same-origin policy by having your server fetch the URL instead of trying to fetch it directly with AJAX and you don't have to use JSONP to do it.

Javascript (jQuery):

function getShowOptionsFromName (name) {
    $.ajax({
        url: "ajax.php",
        method: "GET",
        data: {q: name},
        dataType: "json"
    }).done(function(data){
        console.log(data);
    });
}

PHP (in file ajax.php):

$q = urlencode($_GET["q"]);
echo file_get_contents("http://www.imdb.com/xml/find?json=1&nr=1&tt=on&q=$q");

Send JSON data from Javascript to PHP?

This is a summary of the main solutions with easy-to-reproduce code:

Method 1 (application/json or text/plain + JSON.stringify)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/json") // or "text/plain"
xhr.send(JSON.stringify(data)); 

PHP side, you can get the data with:

print_r(json_decode(file_get_contents('php://input'), true));

Method 2 (x-www-form-urlencoded + JSON.stringify)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send("json=" + encodeURIComponent(JSON.stringify(data))); 

Note: encodeURIComponent(...) is needed for example if the JSON contains & character.

PHP side, you can get the data with:

print_r(json_decode($_POST['json'], true));

Method 3 (x-www-form-urlencoded + URLSearchParams)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send(new URLSearchParams(data).toString()); 

PHP side, you can get the data with:

print_r($_POST);

Note: https://caniuse.com/#search=URLSearchParams

How to determine the IP address of a Solaris system

There's also:

getent $HOSTNAME

or possibly:

getent `uname -n`

On Solaris 11 the ifconfig command is considered legacy and is being replaced by ipadm

ipadm show-addr

will show the IP addresses on the system for Solaris 11 and later.

List Directories and get the name of the Directory

import os
for root, dirs, files in os.walk(top, topdown=False):
    for name in dirs:
        print os.path.join(root, name)

Walk is a good built-in for what you are doing

Remove First and Last Character C++

std::string trimmed(std::string str ) {
if(str.length() == 0 ) { return "" ; }
else if ( str == std::string(" ") ) { return "" ; } 
else {
    while(str.at(0) == ' ') { str.erase(0, 1);}
    while(str.at(str.length()-1) == ' ') { str.pop_back() ; }
    return str ;
    } 
}

How to implement "select all" check box in HTML?

JavaScript is your best bet. The link below gives an example using buttons to de/select all. You could try to adapt it to use a check box, just use you 'select all' check box' onClick attribute.

Javascript Function to Check or Uncheck all Checkboxes

This page has a simpler example

http://www.htmlcodetutorial.com/forms/_INPUT_onClick.html

Bootstrap: Position of dropdown menu relative to navbar item

This is the effect that we're trying to achieve:

A right-aligned menu

The classes that need to be applied changed with the release of Bootstrap 3.1.0 and again with the release of Bootstrap 4. If one of the below solutions doesn't seem to be working double check the version number of Bootstrap that you're importing and try a different one.

Bootstrap 3

Before v3.1.0

You can use the pull-right class to line the right hand side of the menu up with the caret:

<li class="dropdown">
  <a class="dropdown-toggle" href="#">Link</a>
  <ul class="dropdown-menu pull-right">
     <li>...</li>
  </ul>
</li>

Fiddle: http://jsfiddle.net/joeczucha/ewzafdju/

After v3.1.0

As of v3.1.0, we've deprecated .pull-right on dropdown menus. To right-align a menu, use .dropdown-menu-right. Right-aligned nav components in the navbar use a mixin version of this class to automatically align the menu. To override it, use .dropdown-menu-left.

You can use the dropdown-right class to line the right hand side of the menu up with the caret:

<li class="dropdown">
  <a class="dropdown-toggle" href="#">Link</a>
  <ul class="dropdown-menu dropdown-menu-right">
     <li>...</li>
  </ul>
</li>

Fiddle: http://jsfiddle.net/joeczucha/1nrLafxc/

Bootstrap 4

The class for Bootstrap 4 are the same as Bootstrap > 3.1.0, just watch out as the rest of the surrounding markup has changed a little:

<li class="nav-item dropdown">
  <a class="nav-link dropdown-toggle" href="#">
    Link
  </a>
  <div class="dropdown-menu dropdown-menu-right">
    <a class="dropdown-item" href="#">...</a>
  </div>
</li>

Fiddle: https://jsfiddle.net/joeczucha/f8h2tLoc/

I just assigned a variable, but echo $variable shows something else

The answer from ks1322 helped me to identify the issue while using docker-compose exec:

If you omit the -T flag, docker-compose exec add a special character that break output, we see b instead of 1b:

$ test=$(/usr/local/bin/docker-compose exec db bash -c "echo 1")
$ echo "${test}b"
b
echo "${test}" | cat -vte
1^M$

With -T flag, docker-compose exec works as expected:

$ test=$(/usr/local/bin/docker-compose exec -T db bash -c "echo 1")
$ echo "${test}b"
1b

How to get css background color on <tr> tag to span entire row

Try this:

    .rowhighlight > td { background: green;}

How to add a custom right-click menu to a webpage?

Tested and works in Opera 12.17, firefox 30, Internet Explorer 9 and chrome 26.0.1410.64

document.oncontextmenu =function( evt ){
        alert("OK?");
        return false;
        }

REST URI convention - Singular or plural name of resource while creating it

With naming conventions, it's usually safe to say "just pick one and stick to it", which makes sense.

However, after having to explain REST to lots of people, representing endpoints as paths on a file system is the most expressive way of doing it.
It is stateless (files either exist or don't exist), hierarchical, simple, and familiar - you already knows how to access static files, whether locally or via http.

And within that context, linguistic rules can only get you as far as the following:

A directory can contain multiple files and/or sub-directories, and therefore its name should be in plural form.

And I like that.
Although, on the other hand - it's your directory, you can name it "a-resource-or-multiple-resources" if that's what you want. That's not really the important thing.

What's important is that if you put a file named "123" under a directory named "resourceS" (resulting in /resourceS/123), you cannot then expect it to be accessible via /resource/123.

Don't try to make it smarter than it has to be - changing from plural to singluar depending on the count of resources you're currently accessing may be aesthetically pleasing to some, but it's not effective and it doesn't make sense in a hierarchical system.

Note: Technically, you can make "symbolic links", so that /resources/123 can also be accessed via /resource/123, but the former still has to exist!

Set div height to fit to the browser using CSS

You could also use viewport percentages if you don't care about old school IE.

height: 100vh;

android download pdf from url then open it with a pdf reader

This is the best method to download and view PDF file.You can just call it from anywhere as like

PDFTools.showPDFUrl(context, url);

here below put the code. It will works fine

public class PDFTools {
private static final String TAG = "PDFTools";
private static final String GOOGLE_DRIVE_PDF_READER_PREFIX = "http://drive.google.com/viewer?url=";
private static final String PDF_MIME_TYPE = "application/pdf";
private static final String HTML_MIME_TYPE = "text/html";


public static void showPDFUrl(final Context context, final String pdfUrl ) {
    if ( isPDFSupported( context ) ) {
        downloadAndOpenPDF(context, pdfUrl);
    } else {
        askToOpenPDFThroughGoogleDrive( context, pdfUrl );
    }
}


@TargetApi(Build.VERSION_CODES.GINGERBREAD)
public static void downloadAndOpenPDF(final Context context, final String pdfUrl) {
    // Get filename
    //final String filename = pdfUrl.substring( pdfUrl.lastIndexOf( "/" ) + 1 );
    String filename = "";
    try {
        filename = new GetFileInfo().execute(pdfUrl).get();
    } catch (InterruptedException e) {
        e.printStackTrace();
    } catch (ExecutionException e) {
        e.printStackTrace();
    }
    // The place where the downloaded PDF file will be put
    final File tempFile = new File( context.getExternalFilesDir( Environment.DIRECTORY_DOWNLOADS ), filename );
    Log.e(TAG,"File Path:"+tempFile);
    if ( tempFile.exists() ) {
        // If we have downloaded the file before, just go ahead and show it.
        openPDF( context, Uri.fromFile( tempFile ) );
        return;
    }

    // Show progress dialog while downloading
    final ProgressDialog progress = ProgressDialog.show( context, context.getString( R.string.pdf_show_local_progress_title ), context.getString( R.string.pdf_show_local_progress_content ), true );

    // Create the download request
    DownloadManager.Request r = new DownloadManager.Request( Uri.parse( pdfUrl ) );
    r.setDestinationInExternalFilesDir( context, Environment.DIRECTORY_DOWNLOADS, filename );
    final DownloadManager dm = (DownloadManager) context.getSystemService( Context.DOWNLOAD_SERVICE );
    BroadcastReceiver onComplete = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if ( !progress.isShowing() ) {
                return;
            }
            context.unregisterReceiver( this );

            progress.dismiss();
            long downloadId = intent.getLongExtra( DownloadManager.EXTRA_DOWNLOAD_ID, -1 );
            Cursor c = dm.query( new DownloadManager.Query().setFilterById( downloadId ) );

            if ( c.moveToFirst() ) {
                int status = c.getInt( c.getColumnIndex( DownloadManager.COLUMN_STATUS ) );
                if ( status == DownloadManager.STATUS_SUCCESSFUL ) {
                    openPDF( context, Uri.fromFile( tempFile ) );
                }
            }
            c.close();
        }
    };
    context.registerReceiver( onComplete, new IntentFilter( DownloadManager.ACTION_DOWNLOAD_COMPLETE ) );

    // Enqueue the request
    dm.enqueue( r );
}


public static void askToOpenPDFThroughGoogleDrive( final Context context, final String pdfUrl ) {
    new AlertDialog.Builder( context )
            .setTitle( R.string.pdf_show_online_dialog_title )
            .setMessage( R.string.pdf_show_online_dialog_question )
            .setNegativeButton( R.string.pdf_show_online_dialog_button_no, null )
            .setPositiveButton( R.string.pdf_show_online_dialog_button_yes, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    openPDFThroughGoogleDrive(context, pdfUrl);
                }
            })
            .show();
}

public static void openPDFThroughGoogleDrive(final Context context, final String pdfUrl) {
    Intent i = new Intent( Intent.ACTION_VIEW );
    i.setDataAndType(Uri.parse(GOOGLE_DRIVE_PDF_READER_PREFIX + pdfUrl ), HTML_MIME_TYPE );
    context.startActivity( i );
}

public static final void openPDF(Context context, Uri localUri ) {
    Intent i = new Intent( Intent.ACTION_VIEW );
    i.setDataAndType( localUri, PDF_MIME_TYPE );
    context.startActivity( i );
}

public static boolean isPDFSupported( Context context ) {
    Intent i = new Intent( Intent.ACTION_VIEW );
    final File tempFile = new File( context.getExternalFilesDir( Environment.DIRECTORY_DOWNLOADS ), "test.pdf" );
    i.setDataAndType( Uri.fromFile( tempFile ), PDF_MIME_TYPE );
    return context.getPackageManager().queryIntentActivities( i, PackageManager.MATCH_DEFAULT_ONLY ).size() > 0;
}

// get File name from url
static class GetFileInfo extends AsyncTask<String, Integer, String>
{
    protected String doInBackground(String... urls)
    {
        URL url;
        String filename = null;
        try {
            url = new URL(urls[0]);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.connect();
            conn.setInstanceFollowRedirects(false);
            if(conn.getHeaderField("Content-Disposition")!=null){
                String depo = conn.getHeaderField("Content-Disposition");

                String depoSplit[] = depo.split("filename=");
                filename = depoSplit[1].replace("filename=", "").replace("\"", "").trim();
            }else{
                filename = "download.pdf";
            }
        } catch (MalformedURLException e1) {
            e1.printStackTrace();
        } catch (IOException e) {
        }
        return filename;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }
    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);
        // use result as file name
    }
}

}

try it. it will works, enjoy

How to convert a selection to lowercase or uppercase in Sublime Text

For Windows:

  • Ctrl+K,Ctrl+U for UPPERCASE.
  • Ctrl+K,Ctrl+L for lowercase.

Method 1 (Two keys pressed at a time)

  1. Press Ctrl and hold.
  2. Now press K, release K while holding Ctrl. (Do not release the Ctrl key)
  3. Immediately, press U (for uppercase) OR L (for lowercase) with Ctrl still being pressed, then release all pressed keys.

Method 2 (3 keys pressed at a time)

  1. Press Ctrl and hold.
  2. Now press K.
  3. Without releasing Ctrl and K, immediately press U (for uppercase) OR L (for lowercase) and release all pressed keys.

Please note: If you press and hold Ctrl+K for more than two seconds it will start deleting text so try to be quick with it.

I use the above shortcuts, and they work on my Windows system.

How do you stash an untracked file?

I thought this could be solved by telling git that the file exists, rather than committing all of the contents of it to the staging area, and then call git stash. Araqnid describes how to do the former.

git add --intent-to-add path/to/untracked-file

or

git update-index --add --cacheinfo 100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 path/to/untracked-file

However, the latter doesn't work:

$ git stash
b.rb: not added yet
fatal: git-write-tree: error building trees
Cannot save the current index state

Adding calculated column(s) to a dataframe in pandas

The first four functions you list will work on vectors as well, with the exception that lower_wick needs to be adapted. Something like this,

def lower_wick_vec(o, l, c):
    min_oc = numpy.where(o > c, c, o)
    return min_oc - l

where o, l and c are vectors. You could do it this way instead which just takes the df as input and avoid using numpy, although it will be much slower:

def lower_wick_df(df):
    min_oc = df[['Open', 'Close']].min(axis=1)
    return min_oc - l

The other three will work on columns or vectors just as they are. Then you can finish off with

def is_hammer(df):
    lw = lower_wick_at_least_twice_real_body(df["Open"], df["Low"], df["Close"]) 
    cl = closed_in_top_half_of_range(df["High"], df["Low"], df["Close"])
    return cl & lw

Bit operators can perform set logic on boolean vectors, & for and, | for or etc. This is enough to completely vectorize the sample calculations you gave and should be relatively fast. You could probably speed up even more by temporarily working with the numpy arrays underlying the data while performing these calculations.

For the second part, I would recommend introducing a column indicating the pattern for each row and writing a family of functions which deal with each pattern. Then groupby the pattern and apply the appropriate function to each group.

ListView item background via custom selector

FrostWire Team over here.

All the selector crap api doesn't work as expected. After trying all the solutions presented in this thread to no good, we just solved the problem at the moment of inflating the ListView Item.

  1. Make sure your item keeps it's state, we did it as a member variable of the MenuItem (boolean selected)

  2. When you inflate, ask if the underlying item is selected, if so, just set the drawable resource that you want as the background (be it a 9patch or whatever). Make sure your adapter is aware of this and that it calls notifyDataChanged() when something has been selected.

        @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View rowView = convertView;
        if (rowView == null) {
            LayoutInflater inflater = act.getLayoutInflater();
            rowView = inflater.inflate(R.layout.slidemenu_listitem, null);
            MenuItemHolder viewHolder = new MenuItemHolder();
            viewHolder.label = (TextView) rowView.findViewById(R.id.slidemenu_item_label);
            viewHolder.icon = (ImageView) rowView.findViewById(R.id.slidemenu_item_icon);
            rowView.setTag(viewHolder);
        }
    
        MenuItemHolder holder = (MenuItemHolder) rowView.getTag();
        String s = items[position].label;
        holder.label.setText(s);
        holder.icon.setImageDrawable(items[position].icon);
    
        //Here comes the magic
        rowView.setSelected(items[position].selected);
    
        rowView.setBackgroundResource((rowView.isSelected()) ? R.drawable.slidemenu_item_background_selected : R.drawable.slidemenu_item_background);
    
        return rowView;
    }
    

It'd be really nice if the selectors would actually work, in theory it's a nice and elegant solution, but it seems like it's broken. KISS.

Create a dictionary with list comprehension

Here is another example of dictionary creation using dict comprehension:

What i am tring to do here is to create a alphabet dictionary where each pair; is the english letter and its corresponding position in english alphabet

>>> import string
>>> dict1 = {value: (int(key) + 1) for key, value in 
enumerate(list(string.ascii_lowercase))}
>>> dict1
{'a': 1, 'c': 3, 'b': 2, 'e': 5, 'd': 4, 'g': 7, 'f': 6, 'i': 9, 'h': 8, 
'k': 11, 'j': 10, 'm': 13, 'l': 12, 'o': 15, 'n': 14, 'q': 17, 'p': 16, 's': 
19, 'r': 18, 'u': 21, 't': 20, 'w': 23, 'v': 22, 'y': 25, 'x': 24, 'z': 26}
>>> 

Notice the use of enumerate here to get a list of alphabets and their indexes in the list and swapping the alphabets and indices to generate the key value pair for dictionary

Hope it gives a good idea of dictionary comp to you and encourages you to use it more often to make your code compact

How to fix: "You need to use a Theme.AppCompat theme (or descendant) with this activity"

Your application has an AppCompat theme

<application
    android:theme="@style/AppTheme">

But, you overwrote the Activity (which extends AppCompatActivity) with a theme that isn't descendant of an AppCompat theme

<activity android:name=".MainActivity"
    android:theme="@android:style/Theme.NoTitleBar.Fullscreen" >

You could define your own fullscreen theme like so (notice AppCompat in the parent=)

<style name="AppFullScreenTheme" parent="Theme.AppCompat.Light.NoActionBar">
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowActionBar">false</item>
    <item name="android:windowFullscreen">true</item>
    <item name="android:windowContentOverlay">@null</item>
</style>

Then set that on the Activity.

<activity android:name=".MainActivity"
    android:theme="@style/AppFullScreenTheme" >

Note: There might be an AppCompat theme that's already full screen, but don't know immediately

Django URLs TypeError: view must be a callable or a list/tuple in the case of include()

Your code is

urlpatterns = [
    url(r'^$', 'myapp.views.home'),
    url(r'^contact/$', 'myapp.views.contact'),
    url(r'^login/$', 'django.contrib.auth.views.login'),
]

change it to following as you're importing include() function :

urlpatterns = [
    url(r'^$', views.home),
    url(r'^contact/$', views.contact),
    url(r'^login/$', views.login),
]