Programs & Examples On #Lowercase

Lowercase characters are letters in minuscule: a, b, c, …

How to capitalize the first character of each word in a string

String toUpperCaseFirstLetterOnly(String str) {
    String[] words = str.split(" ");
    StringBuilder ret = new StringBuilder();
    for(int i = 0; i < words.length; i++) {
        ret.append(Character.toUpperCase(words[i].charAt(0)));
        ret.append(words[i].substring(1));
        if(i < words.length - 1) {
            ret.append(' ');
        }
    }
    return ret.toString();
}

.toLowerCase not working, replacement function?

.toLowerCase function only exists on strings. You can call toString() on anything in javascript to get a string representation. Putting this all together:

var ans = 334;
var temp = ans.toString().toLowerCase();
alert(temp);

Java Program to test if a character is uppercase/lowercase/number/vowel

You appear to have upper and lowercase back to front. A-Z would be upper, a-z would be lower. While not exactly efficient - with the inverted case exception, I think it should output correctly.

How to convert a string from uppercase to lowercase in Bash?

If you define your variable using declare (old: typeset) then you can state the case of the value throughout the variable's use.

$ declare -u FOO=AbCxxx
$ echo $FOO
ABCXXX

"-l" does lc.

How do I lowercase a string in Python?

Don't try this, totally un-recommend, don't do this:

import string
s='ABCD'
print(''.join([string.ascii_lowercase[string.ascii_uppercase.index(i)] for i in s]))

Output:

abcd

Since no one wrote it yet you can use swapcase (so uppercase letters will become lowercase, and vice versa) (and this one you should use in cases where i just mentioned (convert upper to lower, lower to upper)):

s='ABCD'
print(s.swapcase())

Output:

abcd

How to convert a string to lower or upper case in Ruby

The ruby downcase method returns a string with its uppercase letters replaced by lowercase letters.

"string".downcase

https://ruby-doc.org/core-2.1.0/String.html#method-i-downcase

How to convert array values to lowercase in PHP?

array_change_value_case

by continue

    function array_change_value_case($array, $case = CASE_LOWER){
        if ( ! is_array($array)) return false;
        foreach ($array as $key => &$value){
            if (is_array($value))
            call_user_func_array(__function__, array (&$value, $case ) ) ;
            else
            $array[$key] = ($case == CASE_UPPER )
            ? strtoupper($array[$key])
            : strtolower($array[$key]);
        }
        return $array;
    }


    $arrays = array ( 1 => 'ONE', 2=> 'TWO', 3 => 'THREE',
                     'FOUR' => array ('a' => 'Ahmed', 'b' => 'basem',
                     'c' => 'Continue'),
                      5=> 'FIVE',
                      array('AbCdeF'));


    $change_case = array_change_value_case($arrays, CASE_UPPER);
    echo "<pre>";
    print_r($change_case);
Array
(
 [1] => one
 [2] => two
 [3] => three
 [FOUR] => Array
  (
   [a] => ahmed
   [b] => basem
   [c] => continue
  )

 [5] => five
 [6] => Array
  (
   [0] => abcdef
  )

)

How to convert a string to lower case in Bash?

Simple way

echo "Hi all" | awk '{ print tolower($0); }'

How do I lowercase a string in C?

It's in the standard library, and that's the most straight forward way I can see to implement such a function. So yes, just loop through the string and convert each character to lowercase.

Something trivial like this:

#include <ctype.h>

for(int i = 0; str[i]; i++){
  str[i] = tolower(str[i]);
}

or if you prefer one liners, then you can use this one by J.F. Sebastian:

for ( ; *p; ++p) *p = tolower(*p);

How to detect lowercase letters in Python?

There are many methods to this, here are some of them:

  1. Using the predefined str method islower():

    >>> c = 'a'
    >>> c.islower()
    True
    
  2. Using the ord() function to check whether the ASCII code of the letter is in the range of the ASCII codes of the lowercase characters:

    >>> c = 'a'
    >>> ord(c) in range(97, 123)
    True
    
  3. Checking if the letter is equal to it's lowercase form:

    >>> c = 'a'
    >>> c.lower() == c
    True
    
  4. Checking if the letter is in the list ascii_lowercase of the string module:

    >>> from string import ascii_lowercase
    >>> c = 'a'
    >>> c in ascii_lowercase
    True
    

But that may not be all, you can find your own ways if you don't like these ones: D.

Finally, let's start detecting:

d = str(input('enter a string : '))
lowers = [c for c in d if c.islower()]

# here i used islower() because it's the shortest and most-reliable
# one (being a predefined function), using this list comprehension
# is (probably) the most efficient way of doing this

SQL changing a value to upper or lower case

You can do:

SELECT lower(FIRST NAME) ABC
FROM PERSON

NOTE: ABC is used if you want to change the name of the column

Ignoring upper case and lower case in Java

I have also tried all the posted code until I found out this one

if(math.toLowerCase(Locale.ENGLISH));

Here whatever character the user input will be converted to lower cases.

How do I rename all folders and files to lowercase on Linux?

Smaller still I quite like:

rename 'y/A-Z/a-z/' *

On case insensitive filesystems such as OS X's HFS+, you will want to add the -f flag:

rename -f 'y/A-Z/a-z/' *

Apache is not running from XAMPP Control Panel ( Error: Apache shutdown unexpectedly. This may be due to a blocked port)

Have you executed "setup_xampp.bat" script? It's inside XAMPP folder and it must be executed every time you change XAMPP folder.

How to add new column to MYSQL table?

Based on your comment it looks like your'e only adding the new column if: mysql_query("SELECT * FROM assessment"); returns false. That's probably not what you wanted. Try removing the '!' on front of $sql in the first 'if' statement. So your code will look like:

$sql=mysql_query("SELECT * FROM assessment");
if ($sql) {
 mysql_query("ALTER TABLE assessment ADD q6 INT(1) NOT NULL AFTER q5");
 echo 'Q6 created'; 
}else...

How to remove the Flutter debug banner?

Here are 3 ways to do it

  • 1 : On your MaterialApp set debugShowCheckedModeBanner to false.

     MaterialApp(
       debugShowCheckedModeBanner: false
     )
    

    The slow banner will also automatically be removed on release build.

  • 2 : If you are using Android Studio, you can find the option in the Flutter Inspector tab --> More Actions. enter image description here

  • 3 : There is also another way for removing the "debug" banner from the flutter app. Now after new release there is no "debugShowCheckedModeBanner: false," code line in main. dart file. So I think these methods are effective:

    --> If you are using VS Code, then install "Dart DevTools" from extensions. After installation, you can easily find "Dart DevTools" text icon at the bottom of VS Code. When you click on that text icon, a link will be open in google chrome. From that link page, you can easily remove the banner by just tapping on the banner icon as shown.

enter image description here

For more info: How_to_remove_debug_banner_in_flutter_on_android_emulator

How to complete the RUNAS command in one line

The runas command does not allow a password on its command line. This is by design (and also the reason you cannot pipe a password to it as input). Raymond Chen says it nicely:

The RunAs program demands that you type the password manually. Why doesn't it accept a password on the command line?

This was a conscious decision. If it were possible to pass the password on the command line, people would start embedding passwords into batch files and logon scripts, which is laughably insecure.

In other words, the feature is missing to remove the temptation to use the feature insecurely.

Time comparison

example:

import java.util.*;   
import java.lang.Object;   
import java.text.Collator;   
public class CurrentTime{   
  public class CurrentTime   
{   
    public static void main( String[] args )   
    {   
        Calendar calendar = new GregorianCalendar();   
        String am_pm;   
        int hour = calendar.get( Calendar.HOUR );   
        int minute = calendar.get( Calendar.MINUTE );   
        // int second = calendar.get(Calendar.SECOND);   
        if( calendar.get( Calendar.AM_PM ) == 0 ){   
            am_pm = "AM";   
            if(hour >=10)   
                System.out.println( "welcome" );   
        }               
        else{   
            am_pm = "PM";   
            if(hour<6)   
                System.out.println( "welcome" );   
        }   

        String time = "Current Time : " + hour + ":" + minute + " " + am_pm;   
        System.out.println( time );    
    }   
}  

Source

How do I delete everything in Redis?

This method worked for me - delete everything of current connected Database on your Jedis cluster.

public static void resetRedis() {
    jedisCluster = RedisManager.getJedis(); // your JedisCluster instance

    for (JedisPool pool : jedisCluster.getClusterNodes().values()) {

        try (Jedis jedis = pool.getResource()) {
            jedis.flushAll();
        }
        catch (Exception ex){
            System.out.println(ex.getMessage());
        }
    }

}

INSERT INTO @TABLE EXEC @query with SQL Server 2000

N.B. - this question and answer relate to the 2000 version of SQL Server. In later versions, the restriction on INSERT INTO @table_variable ... EXEC ... were lifted and so it doesn't apply for those later versions.


You'll have to switch to a temp table:

CREATE TABLE #tmp (code varchar(50), mount money)
DECLARE @q nvarchar(4000)
SET @q = 'SELECT coa_code, amount FROM T_Ledger_detail'

INSERT INTO  #tmp (code, mount)
EXEC sp_executesql (@q)

SELECT * from #tmp

From the documentation:

A table variable behaves like a local variable. It has a well-defined scope, which is the function, stored procedure, or batch in which it is declared.

Within its scope, a table variable may be used like a regular table. It may be applied anywhere a table or table expression is used in SELECT, INSERT, UPDATE, and DELETE statements. However, table may not be used in the following statements:

INSERT INTO table_variable EXEC stored_procedure

SELECT select_list INTO table_variable statements.

How do I print colored output to the terminal in Python?

There are a few libraries that help out here. For cmdline tools I sometimes use colorama.

e.g.

from colorama import init, Fore, Back, Style
init()

def cprint(msg, foreground = "black", background = "white"):
    fground = foreground.upper()
    bground = background.upper()
    style = getattr(Fore, fground) + getattr(Back, bground)
    print(style + msg + Style.RESET_ALL)

cprint("colorful output, wohoo", "red", "black")

But instead of using strings, you might want to use an enum and/or add a few checks. Not the prettiest solution, but works on osx/linux and windows and is easy to use.

Other threads about this topic and cross-platform support: e.g. here.

Check file size before upload

JavaScript running in a browser doesn't generally have access to the local file system. That's outside the sandbox. So I think the answer is no.

How to select records from last 24 hours using SQL?

SELECT * 
FROM table_name
WHERE table_name.the_date > DATE_SUB(CURDATE(), INTERVAL 1 DAY)

How do I write the 'cd' command in a makefile?

Like this:

target:
    $(shell cd ....); \
    # ... commands execution in this directory
    # ... no need to go back (using "cd -" or so)
    # ... next target will be automatically in prev dir

Good luck!

How to implement "confirmation" dialog in Jquery UI dialog?

$("ul li a").live('click', function (e) {
            e.preventDefault();

            $('<div></div>').appendTo('body')
                    .html('<div><h6>Are you sure about this?</h6></div>')
                    .dialog({
                        modal: true, title: 'Delete message', zIndex: 10000, autoOpen: true,
                        width: 'auto', modal: true, resizable: false,
                        buttons: {
                            Confirm: function () {
                                // $(obj).removeAttr('onclick');                                
                                // $(obj).parents('.Parent').remove();

                                $(this).dialog("close");

                                window.location.reload();
                            },
                            No: function () {
                                $(this).dialog("close");
                            }
                        },
                        Cancel: function (event, ui) {
                            $(this).remove();
                        }
                    });

            return false;
        });

What data type to use for money in Java?

Java has Currency class that represents the ISO 4217 currency codes. BigDecimal is the best type for representing currency decimal values.

Joda Money has provided a library to represent money.

Referencing another schema in Mongoose

It sounds like the populate method is what your looking for. First make small change to your post schema:

var postSchema = new Schema({
    name: String,
    postedBy: {type: mongoose.Schema.Types.ObjectId, ref: 'User'},
    dateCreated: Date,
    comments: [{body:"string", by: mongoose.Schema.Types.ObjectId}],
});

Then make your model:

var Post = mongoose.model('Post', postSchema);

Then, when you make your query, you can populate references like this:

Post.findOne({_id: 123})
.populate('postedBy')
.exec(function(err, post) {
    // do stuff with post
});

Difference between SRC and HREF

If you're talking HTML4, its list of attributes might help you with the subtleties. They're not interchangeable.

Java POI : How to read Excel cell value and not the formula computing it?

If you want to extract a raw-ish value from a HSSF cell, you can use something like this code fragment:

CellBase base = (CellBase) cell;
CellType cellType = cell.getCellType();
base.setCellType(CellType.STRING);
String result = cell.getStringCellValue();
base.setCellType(cellType);

At least for strings that are completely composed of digits (and automatically converted to numbers by Excel), this returns the original string (e.g. "12345") instead of a fractional value (e.g. "12345.0"). Note that setCellType is available in interface Cell(as of v. 4.1) but deprecated and announced to be eliminated in v 5.x, whereas this method is still available in class CellBase. Obviously, it would be nicer either to have getRawValue in the Cell interface or at least to be able use getStringCellValue on non STRING cell types. Unfortunately, all replacements of setCellType mentioned in the description won't cover this use case (maybe a member of the POI dev team reads this answer).

How to create a custom-shaped bitmap marker with Android map API v2

I hope it still not too late to share my solution. Before that, you can follow the tutorial as stated in Android Developer documentation. To achieve this, you need to use Cluster Manager with defaultRenderer.

  1. Create an object that implements ClusterItem

    public class SampleJob implements ClusterItem {
    
    private double latitude;
    private double longitude;
    
    //Create constructor, getter and setter here
    
    @Override
    public LatLng getPosition() {
        return new LatLng(latitude, longitude);
    }
    
  2. Create a default renderer class. This is the class that do all the job (inflating custom marker/cluster with your own style). I am using Universal image loader to do the downloading and caching the image.

    public class JobRenderer extends DefaultClusterRenderer< SampleJob > {
    
    private final IconGenerator iconGenerator;
    private final IconGenerator clusterIconGenerator;
    private final ImageView imageView;
    private final ImageView clusterImageView;
    private final int markerWidth;
    private final int markerHeight;
    private final String TAG = "ClusterRenderer";
    private DisplayImageOptions options;
    
    
    public JobRenderer(Context context, GoogleMap map, ClusterManager<SampleJob> clusterManager) {
        super(context, map, clusterManager);
    
        // initialize cluster icon generator
        clusterIconGenerator = new IconGenerator(context.getApplicationContext());
        View clusterView = LayoutInflater.from(context).inflate(R.layout.multi_profile, null);
        clusterIconGenerator.setContentView(clusterView);
        clusterImageView = (ImageView) clusterView.findViewById(R.id.image);
    
        // initialize cluster item icon generator
        iconGenerator = new IconGenerator(context.getApplicationContext());
        imageView = new ImageView(context.getApplicationContext());
        markerWidth = (int) context.getResources().getDimension(R.dimen.custom_profile_image);
        markerHeight = (int) context.getResources().getDimension(R.dimen.custom_profile_image);
        imageView.setLayoutParams(new ViewGroup.LayoutParams(markerWidth, markerHeight));
        int padding = (int) context.getResources().getDimension(R.dimen.custom_profile_padding);
        imageView.setPadding(padding, padding, padding, padding);
        iconGenerator.setContentView(imageView);
    
        options = new DisplayImageOptions.Builder()
                .showImageOnLoading(R.drawable.circle_icon_logo)
                .showImageForEmptyUri(R.drawable.circle_icon_logo)
                .showImageOnFail(R.drawable.circle_icon_logo)
                .cacheInMemory(false)
                .cacheOnDisk(true)
                .considerExifParams(true)
                .bitmapConfig(Bitmap.Config.RGB_565)
                .build();
    }
    
    @Override
    protected void onBeforeClusterItemRendered(SampleJob job, MarkerOptions markerOptions) {
    
    
        ImageLoader.getInstance().displayImage(job.getJobImageURL(), imageView, options);
        Bitmap icon = iconGenerator.makeIcon(job.getName());
        markerOptions.icon(BitmapDescriptorFactory.fromBitmap(icon)).title(job.getName());
    
    
    }
    
    @Override
    protected void onBeforeClusterRendered(Cluster<SampleJob> cluster, MarkerOptions markerOptions) {
    
        Iterator<Job> iterator = cluster.getItems().iterator();
        ImageLoader.getInstance().displayImage(iterator.next().getJobImageURL(), clusterImageView, options);
        Bitmap icon = clusterIconGenerator.makeIcon(iterator.next().getName());
        markerOptions.icon(BitmapDescriptorFactory.fromBitmap(icon));
    }
    
    @Override
    protected boolean shouldRenderAsCluster(Cluster cluster) {
        return cluster.getSize() > 1;
    }
    
  3. Apply cluster manager in your activity/fragment class.

    public class SampleActivity extends AppCompatActivity implements OnMapReadyCallback {
    
    private ClusterManager<SampleJob> mClusterManager;
    private GoogleMap mMap;
    private ArrayList<SampleJob> jobs = new ArrayList<SampleJob>();
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_landing);
    
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
    }
    
    
    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        mMap.getUiSettings().setMapToolbarEnabled(true);
        mClusterManager = new ClusterManager<SampleJob>(this, mMap);
        mClusterManager.setRenderer(new JobRenderer(this, mMap, mClusterManager));
        mMap.setOnCameraChangeListener(mClusterManager);
        mMap.setOnMarkerClickListener(mClusterManager);
    
        //Assume that we already have arraylist of jobs
    
    
        for(final SampleJob job: jobs){
            mClusterManager.addItem(job);
        }
        mClusterManager.cluster();
    }
    
  4. Result

Result

Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener

It happen if there are two more ContextLoaderListener exist in your project.

For ex: in my case 2 ContextLoaderListener was exist using

  1. java configuration
  2. web.xml

So, remove any one ContextLoaderListener from your project and run your application.

How do I concatenate strings with variables in PowerShell?

Try this

Get-ChildItem  | % { Write-Host "$($_.FullName)\$buildConfig\$($_.Name).dll" }

In your code,

  1. $build-Config is not a valid variable name.
  2. $.FullName should be $_.FullName
  3. $ should be $_.Name

Check if a variable is of function type

The below seems to work for me as well (tested from node.js):

var isFunction = function(o) {
     return Function.prototype.isPrototypeOf(o);
};

console.log(isFunction(function(){})); // true
console.log(isFunction({})); // false

How can I maintain fragment state when added to the back stack?

I would suggest a very simple solution.

Take the View reference variable and set view in OnCreateView. Check if view already exists in this variable, then return same view.

   private View fragmentView;

   public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        super.onCreateView(inflater, container, savedInstanceState);

        if (fragmentView != null) {
            return fragmentView;
        }
        View view = inflater.inflate(R.layout.yourfragment, container, false);
        fragmentView = view;
        return view;
    }

base64 encoded images in email signatures

Recently I had the same problem to include QR image/png in email. The QR image is a byte array which is generated using ZXing. We do not want to save it to a file because saving/reading from a file is too expensive (slow). So both of the answers above do not work for me. Here's what I did to solve this problem:

import javax.mail.util.ByteArrayDataSource;
import org.apache.commons.mail.ImageHtmlEmail;
...
ImageHtmlEmail email = new ImageHtmlEmail();
byte[] qrImageBytes = createQRCode(); // get your image byte array
ByteArrayDataSource qrImageDataSource = new ByteArrayDataSource(qrImageBytes, "image/png");
String contentId = email.embed(qrImageDataSource, "QR Image");

Let's say the contentId is "111122223333", then your HTML part should have this:

<img src="cid: 111122223333">

There's no need to convert the byte array to Base64 because Commons Mail does the conversion for you automatically. Hope this helps.

Why does the PHP json_encode function convert UTF-8 strings to hexadecimal entities?

JSON_UNESCAPED_UNICODE is available on PHP Version 5.4 or later.
The following code is for Version 5.3.

UPDATED

  • html_entity_decode is a bit more efficient than pack + mb_convert_encoding.
  • (*SKIP)(*FAIL) skips backslashes itself and specified characters by JSON_HEX_* flags.

 

function raw_json_encode($input, $flags = 0) {
    $fails = implode('|', array_filter(array(
        '\\\\',
        $flags & JSON_HEX_TAG ? 'u003[CE]' : '',
        $flags & JSON_HEX_AMP ? 'u0026' : '',
        $flags & JSON_HEX_APOS ? 'u0027' : '',
        $flags & JSON_HEX_QUOT ? 'u0022' : '',
    )));
    $pattern = "/\\\\(?:(?:$fails)(*SKIP)(*FAIL)|u([0-9a-fA-F]{4}))/";
    $callback = function ($m) {
        return html_entity_decode("&#x$m[1];", ENT_QUOTES, 'UTF-8');
    };
    return preg_replace_callback($pattern, $callback, json_encode($input, $flags));
}

How do I generate random numbers in Dart?

Use Dart Generators, that is used to produce a sequence of number or values.

 main(){ 
       print("Sequence Number");
       oddnum(10).forEach(print);
     }
    Iterable<int> oddnum(int num) sync*{
     int k=num;
     while(k>=0){
       if(k%2==1){
        yield k;
       }
      k--;
     } 
}

Intellij Cannot resolve symbol on import

I faced a similar issue, Mike's comment helped me move in the direction to solve it.
Though the required library was a part of the module in my project too, it needed a change of scope. In the module dependency, I changed the scope to "Compile" rather than "Test" and it works fine for me now.

How to terminate a thread when main program ends?

Check this question. The correct answer has great explanation on how to terminate threads the right way: Is there any way to kill a Thread in Python?

To make the thread stop on Keyboard Interrupt signal (ctrl+c) you can catch the exception "KeyboardInterrupt" and cleanup before exiting. Like this:

try:
    start_thread()  
except (KeyboardInterrupt, SystemExit):
    cleanup_stop_thread()
    sys.exit()

This way you can control what to do whenever the program is abruptly terminated.

You can also use the built-in signal module that lets you setup signal handlers (in your specific case the SIGINT signal): http://docs.python.org/library/signal.html

rm: cannot remove: Permission denied

The code says everything:

max@serv$ chmod 777 .

Okay, it doesn't say everything.

In UNIX and Linux, the ability to remove a file is not determined by the access bits of that file. It is determined by the access bits of the directory which contains the file.

Think of it this way -- deleting a file doesn't modify that file. You aren't writing to the file, so why should "w" on the file matter? Deleting a file requires editing the directory that points to the file, so you need "w" on the that directory.

Select specific row from mysql table

You cannot select a row like that. You have to specify a field whose values will be 3

Here is a query that will work, if the field you are comparing against is id

select * from customer where `id` = 3

How do I auto size a UIScrollView to fit its content

Set dynamic content size like this.

 self.scroll_view.contentSize = CGSizeMake(screen_width,CGRectGetMaxY(self.controlname.frame)+20);

identifier "string" undefined?

You must use std namespace. If this code in main.cpp you should write

using namespace std;

If this declaration is in header, then you shouldn't include namespace and just write

std::string level;

Refreshing page on click of a button

<button type="button" onClick="refreshPage()">Close</button>

<script>
function refreshPage(){
    window.location.reload();
} 
</script>

or

<button type="button" onClick="window.location.reload();">Close</button>

How to change symbol for decimal point in double.ToString()?

Some shortcut is to create a NumberFormatInfo class, set its NumberDecimalSeparator property to "." and use the class as parameter to ToString() method whenever u need it.

using System.Globalization;

NumberFormatInfo nfi = new NumberFormatInfo();
nfi.NumberDecimalSeparator = ".";

value.ToString(nfi);

How to disable GCC warnings for a few lines of code

Rather than silencing the warnings, gcc style is usually to use either standard C constructs or the __attribute__ extension to tell the compiler more about your intention. For instance, the warning about assignment used as a condition is suppressed by putting the assignment in parentheses, i.e. if ((p=malloc(cnt))) instead of if (p=malloc(cnt)). Warnings about unused function arguments can be suppressed by some odd __attribute__ I can never remember, or by self-assignment, etc. But generally I prefer just globally disabling any warning option that generates warnings for things that will occur in correct code.

Wamp Server not goes to green color

CMD > netstat -ao > look for any line like 0.0.0.0:80 and look at the PID value (e.g. 4796)

Open Task Manager > Processes tab > View > Select Column > Tick on PID (Process Identifier) > OK to create new column

Look at the processes list in Task Manager > Sort by PID (the new column) and find the 4796 to know which program is using Port 80. Mine is Bit-Torrent. After close (exit) Bit-Torrent, Wampserver should work as usual.

Mailx send html message

There are many different versions of mail around. When you go beyond mail -s subject to1@address1 to2@address2

  • With some mailx implementations, e.g. from mailutils on Ubuntu or Debian's bsd-mailx, it's easy, because there's an option for that.

    mailx -a 'Content-Type: text/html' -s "Subject" to@address <test.html
    
  • With the Heirloom mailx, there's no convenient way. One possibility to insert arbitrary headers is to set editheaders=1 and use an external editor (which can be a script).

    ## Prepare a temporary script that will serve as an editor.
    
    ## This script will be passed to ed.
    temp_script=$(mktemp)
    cat <<'EOF' >>"$temp_script"
    1a
    Content-Type: text/html
    .
    $r test.html
    w
    q
    EOF
    ## Call mailx, and tell it to invoke the editor script
    EDITOR="ed -s $temp_script" heirloom-mailx -S editheaders=1 -s "Subject" to@address <<EOF
    ~e
    .
    EOF
    rm -f "$temp_script"
    
  • With a general POSIX mailx, I don't know how to get at headers.

If you're going to use any mail or mailx, keep in mind that

  • This isn't portable even within a given Linux distribution. For example, both Ubuntu and Debian have several alternatives for mail and mailx.

  • When composing a message, mail and mailx treats lines beginning with ~ as commands. If you pipe text into mail, you need to arrange for this text not to contain lines beginning with ~.

If you're going to install software anyway, you might as well install something more predictable than mail/Mail/mailx. For example, mutt. With Mutt, you can supply most headers in the input with the -H option, but not Content-Type, which needs to be set via a mutt option.

mutt -e 'set content_type=text/html' -s 'hello' 'to@address' <test.html

Or you can invoke sendmail directly. There are several versions of sendmail out there, but they all support sendmail -t to send a mail in the simplest fashion, reading the list of recipients from the mail. (I think they don't all support Bcc:.) On most systems, sendmail isn't in the usual $PATH, it's in /usr/sbin or /usr/lib.

cat <<'EOF' - test.html | /usr/sbin/sendmail -t
To: to@address
Subject: hello
Content-Type: text/html

EOF

No connection string named 'MyEntities' could be found in the application config file

It also happens if the startup project is changed to the one, which does not have the connection strings.

  1. Right Click Solution - click properties
  2. Under Common Properties,select startup project
  3. On the right pane select the project which has the connection strings (in most cases, it will be MVC projects - the project that starts the solution)

Can pandas automatically recognize dates?

Perhaps the pandas interface has changed since @Rutger answered, but in the version I'm using (0.15.2), the date_parser function receives a list of dates instead of a single value. In this case, his code should be updated like so:

dateparse = lambda dates: [pd.datetime.strptime(d, '%Y-%m-%d %H:%M:%S') for d in dates]

df = pd.read_csv(infile, parse_dates=['datetime'], date_parser=dateparse)

Regular expression to get a string between two strings in Javascript

The chosen answer didn't work for me...hmm...

Just add space after cow and/or before milk to trim spaces from " always gives "

/(?<=cow ).*(?= milk)/

enter image description here

How to sum the values of a JavaScript object?

Sum the object key value by parse Integer. Converting string format to integer and summing the values

_x000D_
_x000D_
var obj = {
  pay: 22
};
obj.pay;
console.log(obj.pay);
var x = parseInt(obj.pay);
console.log(x + 20);
_x000D_
_x000D_
_x000D_

How to list active connections on PostgreSQL?

Following will give you active connections/ queries in postgres DB-

SELECT 
    pid
    ,datname
    ,usename
    ,application_name
    ,client_hostname
    ,client_port
    ,backend_start
    ,query_start
    ,query
    ,state
FROM pg_stat_activity
WHERE state = 'active';

You may use 'idle' instead of active to get already executed connections/queries.

Subset and ggplot2

@agstudy's answer didn't work for me with the latest version of ggplot2, but this did, using maggritr pipes:

ggplot(data=dat)+ 
  geom_line(aes(Value1, Value2, group=ID, colour=ID),
                data = . %>% filter(ID %in% c("P1" , "P3")))

It works because if geom_line sees that data is a function, it will call that function with the inherited version of data and use the output of that function as data.

Output a NULL cell value in Excel

I've been frustrated by this problem as well. Find/Replace can be helpful though, because if you don't put anything in the "replace" field it will replace with an -actual- NULL. So the steps would be something along the lines of:

1: Place some unique string in your formula in place of the NULL output (i like to use a password-like string)

2: Run your formula

3: Open Find/Replace, and fill in the unique string as the search value. Leave "replace with" blank

4: Replace All

Obviously, this has limitations. It only works when the context allows you to do a find/replace, so for more dynamic formulas this won't help much. But, I figured I'd put it up here anyway.

Performing Breadth First Search recursively

Here is a BFS recursive traversal Python implementation, working for a graph with no cycle.

def bfs_recursive(level):
    '''
     @params level: List<Node> containing the node for a specific level.
    '''
    next_level = []
    for node in level:
        print(node.value)
        for child_node in node.adjency_list:
            next_level.append(child_node)
    if len(next_level) != 0:
        bfs_recursive(next_level)


class Node:
    def __init__(self, value):
        self.value = value
        self.adjency_list = []

DataTrigger where value is NOT null?

You can use DataTrigger class in Microsoft.Expression.Interactions.dll that come with Expression Blend.

Code Sample:

<i:Interaction.Triggers>
    <i:DataTrigger Binding="{Binding YourProperty}" Value="{x:Null}" Comparison="NotEqual">
       <ie:ChangePropertyAction PropertyName="YourTargetPropertyName" Value="{Binding YourValue}"/>
    </i:DataTrigger
</i:Interaction.Triggers>

Using this method you can trigger against GreaterThan and LessThan too. In order to use this code you should reference two dll's:

System.Windows.Interactivity.dll

Microsoft.Expression.Interactions.dll

Make file echo displaying "$PATH" string

In the manual for GNU make, they talk about this specific example when describing the value function:

The value function provides a way for you to use the value of a variable without having it expanded. Please note that this does not undo expansions which have already occurred; for example if you create a simply expanded variable its value is expanded during the definition; in that case the value function will return the same result as using the variable directly.

The syntax of the value function is:

 $(value variable)

Note that variable is the name of a variable; not a reference to that variable. Therefore you would not normally use a ‘$’ or parentheses when writing it. (You can, however, use a variable reference in the name if you want the name not to be a constant.)

The result of this function is a string containing the value of variable, without any expansion occurring. For example, in this makefile:

 FOO = $PATH

 all:
         @echo $(FOO)
         @echo $(value FOO)

The first output line would be ATH, since the “$P” would be expanded as a make variable, while the second output line would be the current value of your $PATH environment variable, since the value function avoided the expansion.

iPhone App Minus App Store?

With the help of this post, I have made a script that will install via the app Installous for rapid deployment:

# compress application.
/bin/mkdir -p $CONFIGURATION_BUILD_DIR/Payload
/bin/cp -R $CONFIGURATION_BUILD_DIR/MyApp.app $CONFIGURATION_BUILD_DIR/Payload
/bin/cp iTunesCrap/logo_itunes.png $CONFIGURATION_BUILD_DIR/iTunesArtwork
/bin/cp iTunesCrap/iTunesMetadata.plist $CONFIGURATION_BUILD_DIR/iTunesMetadata.plist

cd $CONFIGURATION_BUILD_DIR

# zip up the HelloWorld directory

/usr/bin/zip -r MyApp.ipa Payload iTunesArtwork iTunesMetadata.plist

What Is missing in the post referenced above, is the iTunesMetadata. Without this, Installous will not install apps correctly. Here is an example of an iTunesMetadata:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>appleId</key>
    <string></string>
    <key>artistId</key>
    <integer>0</integer>
    <key>artistName</key>
    <string>MYCOMPANY</string>
    <key>buy-only</key>
    <true/>
    <key>buyParams</key>
    <string></string>
    <key>copyright</key>
    <string></string>
    <key>drmVersionNumber</key>
    <integer>0</integer>
    <key>fileExtension</key>
    <string>.app</string>
    <key>genre</key>
    <string></string>
    <key>genreId</key>
    <integer>0</integer>
    <key>itemId</key>
    <integer>0</integer>
    <key>itemName</key>
    <string>MYAPP</string>
    <key>kind</key>
    <string>software</string>
    <key>playlistArtistName</key>
    <string>MYCOMPANY</string>
    <key>playlistName</key>
    <string>MYAPP</string>
    <key>price</key>
    <integer>0</integer>
    <key>priceDisplay</key>
    <string>nil</string>
    <key>rating</key>
    <dict>
        <key>content</key>
        <string></string>
        <key>label</key>
        <string>4+</string>
        <key>rank</key>
        <integer>100</integer>
        <key>system</key>
        <string>itunes-games</string>
    </dict>
    <key>releaseDate</key>
    <string>Sunday, December 12, 2010</string>
    <key>s</key>
    <integer>143441</integer>
    <key>softwareIcon57x57URL</key>
    <string></string>
    <key>softwareIconNeedsShine</key>
    <false/>
    <key>softwareSupportedDeviceIds</key>
    <array>
        <integer>1</integer>
    </array>
    <key>softwareVersionBundleId</key>
    <string>com.mycompany.myapp</string>
    <key>softwareVersionExternalIdentifier</key>
    <integer>0</integer>
    <key>softwareVersionExternalIdentifiers</key>
    <array>
        <integer>1466803</integer>
        <integer>1529132</integer>
        <integer>1602608</integer>
        <integer>1651681</integer>
        <integer>1750461</integer>
        <integer>1930253</integer>
        <integer>1961532</integer>
        <integer>1973932</integer>
        <integer>2026202</integer>
        <integer>2526384</integer>
        <integer>2641622</integer>
        <integer>2703653</integer>
    </array>
    <key>vendorId</key>
    <integer>0</integer>
    <key>versionRestrictions</key>
    <integer>0</integer>
</dict>
</plist>

Obviously, replace all instances of MyApp with the name of your app and MyCompany with the name of your company.

Basically, this will install on any jailbroken device with Installous installed. After it is set up, this results in very fast deployment, as it can be installed from anywhere, just upload it to your companies website, and download the file directly to the device, and copy / move it to ~/Documents/Installous/Downloads.

Visual Studio window which shows list of methods

There is no direct equivalent to the Outline View in Eclipse. The closest thing I've found is the Class View, which lists all classes and their members/methods. There is a search box at the top to narrow the selection.

req.query and req.param in ExpressJS

req.query will return a JS object after the query string is parsed.

/user?name=tom&age=55 - req.query would yield {name:"tom", age: "55"}

req.params will return parameters in the matched route. If your route is /user/:id and you make a request to /user/5 - req.params would yield {id: "5"}

req.param is a function that peels parameters out of the request. All of this can be found here.

UPDATE

If the verb is a POST and you are using bodyParser, then you should be able to get the form body in you function with req.body. That will be the parsed JS version of the POSTed form.

How to change default format at created_at and updated_at value laravel

If anyone is looking for a simple solution in Laravel 5.3:

  1. Let default timestamps() be saved as is i.e. '2016-11-14 12:19:49'
  2. In your views, format the field as below (or as required):

    date('F d, Y', strtotime($list->created_at))
    

It worked for me very well for me.

Converting a double to an int in C#

In the provided example your decimal is 8.6. Had it been 8.5 or 9.5, the statement i1 == i2 might have been true. Infact it would have been true for 8.5, and false for 9.5.

Explanation:

Regardless of the decimal part, the second statement, int i2 = (int)score will discard the decimal part and simply return you the integer part. Quite dangerous thing to do, as data loss might occur.

Now, for the first statement, two things can happen. If the decimal part is 5, that is, it is half way through, a decision is to be made. Do we round up or down? In C#, the Convert class implements banker's rounding. See this answer for deeper explanation. Simply put, if the number is even, round down, if the number is odd, round up.

E.g. Consider:

        double score = 8.5;
        int i1 = Convert.ToInt32(score); // 8
        int i2 = (int)score;             // 8

        score += 1;
        i1 = Convert.ToInt32(score);     // 10
        i2 = (int)score;                 // 9

Bash: Echoing a echo command with a variable in bash

The immediate problem is you have is with quoting: by using double quotes ("..."), your variable references are instantly expanded, which is probably not what you want.

Use single quotes instead - strings inside single quotes are not expanded or interpreted in any way by the shell.

(If you want selective expansion inside a string - i.e., expand some variable references, but not others - do use double quotes, but prefix the $ of references you do not want expanded with \; e.g., \$var).

However, you're better off using a single here-doc[ument], which allows you to create multi-line stdin input on the spot, bracketed by two instances of a self-chosen delimiter, the opening one prefixed by <<, and the closing one on a line by itself - starting at the very first column; search for Here Documents in man bash or at http://www.gnu.org/software/bash/manual/html_node/Redirections.html.

If you quote the here-doc delimiter (EOF in the code below), variable references are also not expanded. As @chepner points out, you're free to choose the method of quoting in this case: enclose the delimiter in single quotes or double quotes, or even simply arbitrarily escape one character in the delimiter with \:

echo "creating new script file."

cat <<'EOF'  > "$servfile"
#!/bin/bash
read -p "Please enter a service: " ser
servicetest=`getsebool -a | grep ${ser}` 
if [ $servicetest > /dev/null ]; then 
  echo "we are now going to work with ${ser}"
else
  exit 1
fi
EOF

As @BruceK notes, you can prefix your here-doc delimiter with - (applied to this example: <<-"EOF") in order to have leading tabs stripped, allowing for indentation that makes the actual content of the here-doc easier to discern. Note, however, that this only works with actual tab characters, not leading spaces.

Employing this technique combined with the afterthoughts regarding the script's content below, we get (again, note that actual tab chars. must be used to lead each here-doc content line for them to get stripped):

cat <<-'EOF' > "$servfile"
    #!/bin/bash
    read -p "Please enter a service name: " ser
    if [[ -n $(getsebool -a | grep "${ser}") ]]; then 
      echo "We are now going to work with ${ser}."
    else
      exit 1
    fi
EOF

Finally, note that in bash even normal single- or double-quoted strings can span multiple lines, but you won't get the benefits of tab-stripping or line-block scoping, as everything inside the quotes becomes part of the string.

Thus, note how in the following #!/bin/bash has to follow the opening ' immediately in order to become the first line of output:

echo '#!/bin/bash
read -p "Please enter a service: " ser
servicetest=$(getsebool -a | grep "${ser}")
if [[ -n $servicetest ]]; then 
  echo "we are now going to work with ${ser}"
else
  exit 1
fi' > "$servfile"

Afterthoughts regarding the contents of your script:

  • The syntax $(...) is preferred over `...` for command substitution nowadays.
  • You should double-quote ${ser} in the grep command, as the command will likely break if the value contains embedded spaces (alternatively, make sure that the valued read contains no spaces or other shell metacharacters).
  • Use [[ -n $servicetest ]] to test whether $servicetest is empty (or perform the command substitution directly inside the conditional) - [[ ... ]] - the preferred form in bash - protects you from breaking the conditional if the $servicetest happens to have embedded spaces; there's NEVER a need to suppress stdout output inside a conditional (whether [ ... ] or [[ ... ]], as no stdout output is passed through; thus, the > /dev/null is redundant (that said, with a command substitution inside a conditional, stderr output IS passed through).

How to inspect FormData?

You have to understand that FormData::entries() returns an instance of Iterator.

Take this example form:

<form name="test" id="form-id">
    <label for="name">Name</label>
    <input name="name" id="name" type="text">
    <label for="pass">Password</label>
    <input name="pass" id="pass" type="text">
</form>

and this JS-loop:

<script>
    var it = new FormData( document.getElementById('form-id') ).entries();
    var current = {};
    while ( ! current.done ) {
        current = it.next();
        console.info( current )
    }
</script>

Updating user data - ASP.NET Identity

Excellent!!!

IdentityResult result = await UserManager.UpdateAsync(user);

VBA using ubound on a multidimensional array

In addition to the already excellent answers, also consider this function to retrieve both the number of dimensions and their bounds, which is similar to John's answer, but works and looks a little differently:

Function sizeOfArray(arr As Variant) As String
    Dim str As String
    Dim numDim As Integer

    numDim = NumberOfArrayDimensions(arr)
    str = "Array"

    For i = 1 To numDim
        str = str & "(" & LBound(arr, i) & " To " & UBound(arr, i)
        If Not i = numDim Then
            str = str & ", "
        Else
            str = str & ")"
        End If
    Next i

    sizeOfArray = str
End Function


Private Function NumberOfArrayDimensions(arr As Variant) As Integer
' By Chip Pearson
' http://www.cpearson.com/excel/vbaarrays.htm
Dim Ndx As Integer
Dim Res As Integer
On Error Resume Next
' Loop, increasing the dimension index Ndx, until an error occurs.
' An error will occur when Ndx exceeds the number of dimension
' in the array. Return Ndx - 1.
    Do
        Ndx = Ndx + 1
        Res = UBound(arr, Ndx)
    Loop Until Err.Number <> 0
NumberOfArrayDimensions = Ndx - 1
End Function

Example usage:

Sub arrSizeTester()
    Dim arr(1 To 2, 3 To 22, 2 To 9, 12 To 18) As Variant
    Debug.Print sizeOfArray(arr())
End Sub

And its output:

Array(1 To 2, 3 To 22, 2 To 9, 12 To 18)

Git: cannot checkout branch - error: pathspec '...' did not match any file(s) known to git

None of these answers solved my issue:

Nikolai@CALIGARI-7 ~/Documents/NetBeansProjects/Version (master)
$ git log --format=oneline
b9cc6a9078312865280fb5432a43e17eff03a5c6 Formatted README
288772f36befe6bd60dd41b8185f1e24e0119668 Updated README documentation
d2bdbe18f4169358d46fad50eacfb89786df3bf8 Version object v3.0.0-SNAPSHOT
a46b1910a3f548b4fa254a6055d25f68d3f217dd VersionFactory is now Platform agnostic
24179ae569ec7bd28311389c0a7a85ea7b4f9594 Added internal.Platform abstraction
252b684417cf4edd71aed43a15da2c8a59c629a7 Added IPlugin implementation for Sponge
e3f8d21d6cf61ee4fc806791689c984c149b45e3 Added IPlugin implementation for Bukkit
aeb403914310b4b10dee9e980cf64472e2bfda79 Refactored Version.java
ef50efcff700c6438d57f70fac30846de2747a7e Refactored TesterFactory
a20808065878d4d28657ae362235c837cfa8e625 Added IPlugin abstraction
9712a3575a70060d7ecea8b62bb5e888fdc32d07 Heavily refactored Tester
02d025788ae740dbfe3ef76a132cea8ca4e47467 Added generic Predicate<T> interface
9c565777abea9be6767dfdab4ab94ed1173750dd Minor refactoring of testCompareTo()
2ff2a28c221681e256dcff28770782736d3a796a Version object v2.0.1
d4b2e2bd830f77cdbc2297112c2e46b6555d4393 Fix compareTo()
05fe7e012b07d1a5b8de29804f96d9a6b24229a1 Make compareTo() fail
6e85371414357a41c1fc0cec0e75adba92f96832 Fix VersionFactory passing null
c1fd1f032f87d860d5ed9d6f6679c9fa522cff8d Version object v2.0
62c3a92c008a2ed11f0a4d016080afc3541d0700 Version object v1.2
c42e9e617128085e872c51b4d977a04e48d69e8f Deprecated, doc'd, future-proofed getNm


Nikolai@CALIGARI-7 ~/Documents/NetBeansProjects/Version (master)
$ git checkout 3a796a
error: pathspec '3a796a' did not match any file(s) known to git.

I was trying to go back and build the commit for Version object v2.0.1. Luckily, I got the idea to try the whole hash code and it worked ! Which means that I was using the wrong end of the hash code.

Nikolai@CALIGARI-7 ~/Documents/NetBeansProjects/Version (master)
$ git checkout 2ff2a
Note: checking out '2ff2a'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by performing another checkout.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -b with the checkout command again. Example:

  git checkout -b new_branch_name

HEAD is now at 2ff2a28... Version object v2.0.1

Nikolai@CALIGARI-7 ~/Documents/NetBeansProjects/Version ((2ff2a28...))
$

As shown above, for partial hash codes, you must supply the front-end, not the back-end.

What is the difference between public, private, and protected?

The mentioned keywords are access modifiers and help us implement Encapsulation (or information hiding). They tell the compiler which other classes should have access to the field or method being defined.

private - Only the current class will have access to the field or method.

protected - Only the current class and subclasses (and sometimes also same-package classes) of this class will have access to the field or method.

public - Any class can refer to the field or call the method.

Empty ArrayList equals null

No, this will not work. The best you will be able to do is to iterate through all values and check them yourself:

boolean empty = true;
for (Object item : arrayList) {
    if (item != null) {
        empty = false;
        break;
    }
}

How to read an external local JSON file in JavaScript?

I took Stano's excellent answer and wrapped it in a promise. This might be useful if you don't have an option like node or webpack to fall back on to load a json file from the file system:

// wrapped XMLHttpRequest in a promise
const readFileP = (file, options = {method:'get'}) => 
  new Promise((resolve, reject) => {
    let request = new XMLHttpRequest();
    request.onload = resolve;
    request.onerror = reject;
    request.overrideMimeType("application/json");
    request.open(options.method, file, true);
    request.onreadystatechange = () => {
        if (request.readyState === 4 && request.status === "200") {
            resolve(request.responseText);
        }
    };
    request.send(null);
});

You can call it like this:

readFileP('<path to file>')
    .then(d => {
      '<do something with the response data in d.srcElement.response>'
    });

Creating .pem file for APNS?

Here is what I did, From:blog.boxedice.com and "iPhone Advanced Projects" chapter 10 byJoe Pezzillo.

With the aps_developer_identity.cer in the keychain:

  1. Launch Keychain Access from your local Mac and from the login keychain, filter by the Certificates category. You will see an expandable option called “Apple Development Push Services”
  2. Right click on “Apple Development Push Services” > Export “Apple Development Push Services ID123". Save this as apns-dev-cert.p12 file somewhere you can access it. There is no need to enter a password.
  3. The next command generates the cert in Mac’s Terminal for PEM format (Privacy Enhanced Mail Security Certificate):

    openssl pkcs12 -in apns-dev-cert.p12 -out apns-dev-cert.pem -nodes -clcerts
    

On the server set the file permission of this unencrypted key by using chmod 400.

PHP display image BLOB from MySQL

Try Like this.

For Inserting into DB

$db = mysqli_connect("localhost","root","","DbName"); //keep your db name
$image = addslashes(file_get_contents($_FILES['images']['tmp_name']));
//you keep your column name setting for insertion. I keep image type Blob.
$query = "INSERT INTO products (id,image) VALUES('','$image')";  
$qry = mysqli_query($db, $query);

For Accessing image From Blob

$db = mysqli_connect("localhost","root","","DbName"); //keep your db name
$sql = "SELECT * FROM products WHERE id = $id";
$sth = $db->query($sql);
$result=mysqli_fetch_array($sth);
echo '<img src="data:image/jpeg;base64,'.base64_encode( $result['image'] ).'"/>';

Hope It will help you.

Thanks.

jQuery/JavaScript to replace broken images

I couldn't find a script to suit my needs, so I made a recursive function to check for broken images and attempt to reload them every four seconds until they are fixed.

I limited it to 10 attempts as if it's not loaded by then the image might not be present on server and the function would enter an infinite loop. I am still testing though. Feel free to tweak it :)

var retries = 0;
$.imgReload = function() {
    var loaded = 1;

    $("img").each(function() {
        if (!this.complete || typeof this.naturalWidth == "undefined" || this.naturalWidth == 0) {

            var src = $(this).attr("src");
            var date = new Date();
            $(this).attr("src", src + "?v=" + date.getTime()); //slightly change url to prevent loading from cache
            loaded =0;
        }
    });

    retries +=1;
    if (retries < 10) { // If after 10 retries error images are not fixed maybe because they
                        // are not present on server, the recursion will break the loop
        if (loaded == 0) {
            setTimeout('$.imgReload()',4000); // I think 4 seconds is enough to load a small image (<50k) from a slow server
        }
        // All images have been loaded
        else {
            // alert("images loaded");
        }
    }
    // If error images cannot be loaded  after 10 retries
    else {
        // alert("recursion exceeded");
    }
}

jQuery(document).ready(function() {
    setTimeout('$.imgReload()',5000);
});

Pointer to incomplete class type is not allowed

You get this error when declaring a forward reference inside the wrong namespace thus declaring a new type without defining it. For example:

namespace X
{
  namespace Y
  {
    class A;

    void func(A* a) { ... } // incomplete type here!
  }
}

...but, in class A was defined like this:

namespace X
{
  class A { ... };
}

Thus, A was defined as X::A, but I was using it as X::Y::A.

The fix obviously is to move the forward reference to its proper place like so:

namespace X
{
  class A;
  namespace Y
  {
    void func(X::A* a) { ... } // Now accurately referencing the class`enter code here`
  }
}

How to get number of rows inserted by a transaction

In case you need further info for your log/audit you can OUTPUT clause: This way, not only you keep the number of rows affected, but also what records.

As an example of the Output Clause during inserts: SQL Server list of insert identities

DECLARE @InsertedIDs table(ID int);

INSERT INTO YourTable
    OUTPUT INSERTED.ID
        INTO @InsertedIDs 
    SELECT ...

HTH

how to open a url in python

Here is another way to do it.

import webbrowser

webbrowser.open("foobar.com")

What exactly should be set in PYTHONPATH?

Here is what I learned: PYTHONPATH is a directory to add to the Python import search path "sys.path", which is made up of current dir. CWD, PYTHONPATH, standard and shared library, and customer library. For example:

% python3 -c "import sys;print(sys.path)"
['', 
'/home/username/Documents/DjangoTutorial/mySite', 
'/usr/lib/python3.6', '/usr/lib/python3.6/lib-dynload', 
'/usr/local/lib/python3.6/dist-packages', '/usr/lib/python3/dist-packages']

where the first path '' denotes the current dir., the 2nd path is via

%export PYTHONPATH=/home/username/Documents/DjangoTutorial/mySite 

which can be added to ~/.bashrc to make it permanent, and the rest are Python standard and dynamic shared library plus third-party library such as django.

As said not to mess with PYTHONHOME, even setting it to '' or 'None' will cause python3 shell to stop working:

% export PYTHONHOME=''
% python3
Fatal Python error: Py_Initialize: Unable to get the locale encoding
ModuleNotFoundError: No module named 'encodings'

Current thread 0x00007f18a44ff740 (most recent call first):
Aborted (core dumped)

Note that if you start a Python script, the CWD will be the script's directory. For example:

username@bud:~/Documents/DjangoTutorial% python3 mySite/manage.py runserver
==== Printing sys.path ====
/home/username/Documents/DjangoTutorial/mySite # CWD is where manage.py resides
/usr/lib/python3.6
/usr/lib/python3.6/lib-dynload
/usr/local/lib/python3.6/dist-packages
/usr/lib/python3/dist-packages

You can also append a path to sys.path at run-time: Suppose you have a file Fibonacci.py in ~/Documents/Python directory:

username@bud:~/Documents/DjangoTutorial% python3 
>>> sys.path.append("/home/username/Documents")
>>> print(sys.path)
['', '/usr/lib/python3.6', '/usr/lib/python3.6/lib-dynload', 
'/usr/local/lib/python3.6/dist-packages', '/usr/lib/python3/dist-packages', 
'/home/username/Documents']
>>> from Python import Fibonacci as fibo

or via

% PYTHONPATH=/home/username/Documents:$PYTHONPATH
% python3
>>> print(sys.path)
['', 
'/home/username/Documents', '/home/username/Documents/DjangoTutorial/mySite', 
'/usr/lib/python3.6', '/usr/lib/python3.6/lib-dynload', 
'/usr/local/lib/python3.6/dist-packages', '/usr/lib/python3/dist-packages']
>>> from Python import Fibonacci as fibo

Why "no projects found to import"?

One solution to this is to use Maven. From the project root folder do mvn eclipse:clean followed by mvn eclipse:eclipse. This will generate the .project and .classpath files required by eclipse.

How to automatically start a service when running a docker container?

I have the same problem when I want to automatically start ssh service. I found that append

/etc/init.d/ssh start
to
~/.bashrc
can resolve it ,but only you open it with bash will do.

Using R to list all files with a specified extension

Peg the pattern to find "\\.dbf" at the end of the string using the $ character:

list.files(pattern = "\\.dbf$")

Check if file exists and whether it contains a specific string

You should use the grep -q flag for quiet output. See the man pages below:

man grep output :

 General Output Control

  -q, --quiet, --silent
              Quiet;  do  not write anything to standard output.  Exit immediately with zero status
              if any match is  found,  even  if  an  error  was  detected.   Also  see  the  -s  or
              --no-messages option.  (-q is specified by POSIX.)

This KornShell (ksh) script demos the grep quiet output and is a solution to your question.

grepUtil.ksh :

#!/bin/ksh

#Initialize Variables
file=poet.txt
var=""
dir=tempDir
dirPath="/"${dir}"/"
searchString="poet"

#Function to initialize variables
initialize(){
    echo "Entering initialize"
    echo "Exiting initialize"
}

#Function to create File with Input
#Params: 1}Directory 2}File 3}String to write to FileName
createFileWithInput(){
    echo "Entering createFileWithInput"
    orgDirectory=${PWD}
    cd ${1}
    > ${2}
    print ${3} >> ${2}
    cd ${orgDirectory}
    echo "Exiting createFileWithInput"
}

#Function to create File with Input
#Params: 1}directoryName
createDir(){
    echo "Entering createDir"
    mkdir -p ${1}
    echo "Exiting createDir"
}

#Params: 1}FileName
readLine(){
    echo "Entering readLine"
    file=${1}
    while read line
    do
        #assign last line to var
        var="$line"
    done <"$file"
    echo "Exiting readLine"
}
#Check if file exists 
#Params: 1}File
doesFileExit(){
    echo "Entering doesFileExit"
    orgDirectory=${PWD}
    cd ${PWD}${dirPath}
    #echo ${PWD}
    if [[ -e "${1}" ]]; then
        echo "${1} exists"
    else
        echo "${1} does not exist"
    fi
    cd ${orgDirectory}
    echo "Exiting doesFileExit"
}
#Check if file contains a string quietly
#Params: 1}Directory Path 2}File 3}String to seach for in File
doesFileContainStringQuiet(){
    echo "Entering doesFileContainStringQuiet"
    orgDirectory=${PWD}
    cd ${PWD}${1}
    #echo ${PWD}
    grep -q ${3} ${2}
    if [ ${?} -eq 0 ];then
        echo "${3} found in ${2}"
    else
        echo "${3} not found in ${2}"
    fi
    cd ${orgDirectory}
    echo "Exiting doesFileContainStringQuiet"
}
#Check if file contains a string with output
#Params: 1}Directory Path 2}File 3}String to seach for in File
doesFileContainString(){
    echo "Entering doesFileContainString"
    orgDirectory=${PWD}
    cd ${PWD}${1}
    #echo ${PWD}
    grep ${3} ${2}
    if [ ${?} -eq 0 ];then
        echo "${3} found in ${2}"
    else
        echo "${3} not found in ${2}"
    fi
    cd ${orgDirectory}
    echo "Exiting doesFileContainString"
}

#-----------
#---Main----
#-----------
echo "Starting: ${PWD}/${0} with Input Parameters: {1: ${1} {2: ${2} {3: ${3}"
#initialize #function call#
createDir ${dir} #function call#
createFileWithInput ${dir} ${file} ${searchString} #function call#
doesFileExit ${file} #function call#
if [ ${?} -eq 0 ];then
    doesFileContainStringQuiet ${dirPath} ${file} ${searchString} #function call#
    doesFileContainString ${dirPath} ${file} ${searchString} #function call#
fi
echo "Exiting: ${PWD}/${0}"

grepUtil.ksh Output :

user@foo /tmp
$ ksh grepUtil.ksh
Starting: /tmp/grepUtil.ksh with Input Parameters: {1:  {2:  {3:
Entering createDir
Exiting createDir
Entering createFileWithInput
Exiting createFileWithInput
Entering doesFileExit
poet.txt exists
Exiting doesFileExit
Entering doesFileContainStringQuiet
poet found in poet.txt
Exiting doesFileContainStringQuiet
Entering doesFileContainString
poet
poet found in poet.txt
Exiting doesFileContainString
Exiting: /tmp/grepUtil.ksh

Jquery select this + class

Well using find is the best option here

just simply use like this

$(".class").click(function(){
        $("this").find('.subclass').css("visibility","visible");
})

and if there are many classes with the same name class its always better to give the class name of parent class like this

$(".parent .class").click(function(){
            $("this").find('.subclass').css("visibility","visible");
    })

SVN - Checksum mismatch while updating

My solution was:

  1. Execute svn cleanup from file system
  2. Switch to another branch
  3. Solve conflicts
  4. Switch to the "problematic" branch
  5. Execute cleanup from Spring Tool Suite
  6. Execute Project Update

Calculating Page Table Size

My explanation uses elementary building blocks that helped me to understand. Note I am leveraging @Deepak Goyal's answer above since he provided clarity:

We were given a logical 32-bit address space (i.e. We have a 32 bit computer)

Consider a system with a 32-bit logical address space

We were also told that

each page size is 4 KB

  • 1 KB (kilobyte) = 1 x 1024 bytes = 2^10 bytes
  • 4 x 1024 bytes = 2^2 x 2^10 bytes => 4 KB (i.e. 2^12 bytes)
  • The size of each page is thus 4 KB (Kilobytes NOT kilobits).

As Depaak said, we calculate the number of pages in the page table with this formula:

Num_Pages_in_PgTable = Total_Possible_Logical_Address_Entries / page size 
Num_Pages_in_PgTable =         2^32                           /    2^12
Num_Pages_in_PgTable = 2^20 (i.e. 1 million) 

The authors go on to give the case where each entry in the page table takes 4 bytes. That means that the total size of the page table in physical memory will be 4MB:

Memory_Required_Per_Page = Size_of_Page_Entry_in_bytes x Num_Pages_in_PgTable
Memory_Required_Per_Page =           4                 x     2^20
Memory_Required_Per_Page =     4 MB (Megabytes)

So yes, each process would require at least 4MB of memory to run, in increments of 4MB.

Example

Now if a professor wanted to make the question a bit more challenging than the explanation from the book, they might ask about a 64-bit computer. Let's say they want memory in bits. To solve the question, we'd follow the same process, only being sure to convert MB to Mbits.

Let's step through this example.

Givens:

  • Logical address space: 64-bit
  • Page Size: 4KB
  • Entry_Size_Per_Page: 4 bytes

Recall: A 64-bit entry can point to one of 2^64 physical page frames - Since Page size is 4 KB, then we still have 2^12 byte page sizes

  • 1 KB (kilobyte) = 1 x 1024 bytes = 2^10 bytes
  • Size of each page = 4 x 1024 bytes = 2^2 x 2^10 bytes = 2^12 bytes

How Many pages In Page Table?

`Num_Pages_in_PgTable = Total_Possible_Logical_Address_Entries / page size 
Num_Pages_in_PgTable =         2^64                            /    2^12
Num_Pages_in_PgTable =         2^52 
Num_Pages_in_PgTable =      2^2 x 2^50 
Num_Pages_in_PgTable =       4  x 2^50 `  

How Much Memory in BITS Per Page?

Memory_Required_Per_Page = Size_of_Page_Entry_in_bytes x Num_Pages_in_PgTable 
Memory_Required_Per_Page =   4 bytes x 8 bits/byte    x     2^52
Memory_Required_Per_Page =     32 bits                x   2^2 x 2^50
Memory_Required_Per_Page =     32 bits                x    4  x 2^50
Memory_Required_Per_Page =     128 Petabits

[2]: Operating System Concepts (9th Ed) - Gagne, Silberschatz, and Galvin

How can I measure the similarity between two images?

A ruby solution can be found here

From the readme:

Phashion is a Ruby wrapper around the pHash library, "perceptual hash", which detects duplicate and near duplicate multimedia files

IPython Notebook save location

Yes, you can specify the notebooks location in your profile configuration. Since it's not saving them to the directory where you started the notebook, I assume that you have this option set in your profile. You can find out the the path to the profiles directory by using:

$ ipython locate

Either in your default profile or in the profile you use, edit the ipython_notebook_config.py file and change the lines:

Note: In case you don't have a profile, or the profile folder does not contain the ipython_notebook_config.py file, use ipython profile create.

# The directory to use for notebooks.
c.NotebookManager.notebook_dir = u'/path/to/your/notebooks'

and

# The directory to use for notebooks.
c.FileNotebookManager.notebook_dir = u'/path/to/your/notebooks'

Or just comment them out if you want the notebooks saved in the current directory.

Update (April 11th 2014): in IPython 2.0 the property name in the config file changed, so it's now:

c.NotebookApp.notebook_dir = u'/path/to/your/notebooks'

Getting a list of values from a list of dicts

I think as simple as below would give you what you are looking for.

In[5]: ll = [{'value': 'apple', 'blah': 2}, {'value': 'banana', 'blah': 3} , {'value': 'cars', 'blah':4}]
In[6]: ld = [d.get('value', None) for d in ll]
In[7]: ld
Out[7]: ['apple', 'banana', 'cars']

You can do this with a combination of map and lambda as well but list comprehension looks more elegant and pythonic.

For a smaller input list comprehension is way to go but if the input is really big then i guess generators are the ideal way.

In[11]: gd = (d.get('value', None) for d in ll)
In[12]: gd
Out[12]: <generator object <genexpr> at 0x7f5774568b10>
In[13]: '-'.join(gd)
Out[13]: 'apple-banana-cars'

Here is a comparison of all possible solutions for bigger input

 In[2]: l = [{'value': 'apple', 'blah': 2}, {'value': 'banana', 'blah': 3} , {'value': 'cars', 'blah':4}] * 9000000
In[3]: def gen_version():
  ...:     for i in l:
  ...:         yield i.get('value', None)
  ...: 
In[4]: def list_comp_verison():
  ...:     return [i.get('value', None) for i in l]
  ...: 
In[5]: def list_verison():
  ...:     ll = []
  ...:     for i in l:
  ...:         ll.append(i.get('value', None))
  ...:     return ll
In[10]: def map_lambda_version():
   ...:      m = map(lambda i:i.get('value', None), l)
   ...:      return m
   ...: 
In[11]: %timeit gen_version()
172 ns ± 0.393 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)
In[12]: %timeit map_lambda_version()
203 ns ± 2.31 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)
In[13]: %timeit list_comp_verison()
1.61 s ± 20.4 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)
In[14]: %timeit list_verison()
2.29 s ± 4.58 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)

As you can see, generators are a better solution in comparison to the others, map is also slower compared to generator for reason I will leave up to OP to figure out.

No plot window in matplotlib

If you are starting IPython with the --pylab option, you shouldn't need to call show() or draw(). Try this:

ipython  --pylab=inline

Why won't my PHP app send a 404 error?

Another solution, based on @Kitet's.

header($_SERVER["SERVER_PROTOCOL"]." 404 Not Found");
header("Status: 404 Not Found");

$_SERVER['REDIRECT_STATUS'] = 404;
//If you don't know which web page is in use, use any page that doesn't exists
$handle = curl_init('http://'. $_SERVER["HTTP_HOST"] .'/404missing.html');
curl_exec($handle);

If you are programming a website that hosted in a server you do not have control, you will not know which file is the "404missing.html". However you can still do this.

In this way, you provided exactly the same outcome of a normal 404 page on the same server. An observer will not be able to distinguish between an existing PHP page returns 404 and a non-existing page.

Splitting string with pipe character ("|")

| is a metacharacter in regex. You'd need to escape it:

String[] value_split = rat_values.split("\\|");

find if an integer exists in a list of integers

bool vExist = false;
int vSelectValue = 1;

List<int> vList = new List<int>();
vList.Add(1);
vList.Add(2);

IEnumerable vRes = (from n in vListwhere n == vSelectValue);
if (vRes.Count > 0) {
    vExist = true;
}

Difference between Visibility.Collapsed and Visibility.Hidden

The difference is that Visibility.Hidden hides the control, but reserves the space it occupies in the layout. So it renders whitespace instead of the control. Visibilty.Collapsed does not render the control and does not reserve the whitespace. The space the control would take is 'collapsed', hence the name.

The exact text from the MSDN:

Collapsed: Do not display the element, and do not reserve space for it in layout.

Hidden: Do not display the element, but reserve space for the element in layout.

Visible: Display the element.

See: http://msdn.microsoft.com/en-us/library/system.windows.visibility.aspx

PHP How to find the time elapsed since a date time?

I liked Mithun's code, but I tweaked it a bit to make it give more reasonable answers.

function getTimeSince($eventTime)
{
    $totaldelay = time() - strtotime($eventTime);
    if($totaldelay <= 0)
    {
        return '';
    }
    else
    {
        $first = '';
        $marker = 0;
        if($years=floor($totaldelay/31536000))
        {
            $totaldelay = $totaldelay % 31536000;
            $plural = '';
            if ($years > 1) $plural='s';
            $interval = $years." year".$plural;
            $timesince = $timesince.$first.$interval;
            if ($marker) return $timesince;
            $marker = 1;
            $first = ", ";
        }
        if($months=floor($totaldelay/2628000))
        {
            $totaldelay = $totaldelay % 2628000;
            $plural = '';
            if ($months > 1) $plural='s';
            $interval = $months." month".$plural;
            $timesince = $timesince.$first.$interval;
            if ($marker) return $timesince;
            $marker = 1;
            $first = ", ";
        }
        if($days=floor($totaldelay/86400))
        {
            $totaldelay = $totaldelay % 86400;
            $plural = '';
            if ($days > 1) $plural='s';
            $interval = $days." day".$plural;
            $timesince = $timesince.$first.$interval;
            if ($marker) return $timesince;
            $marker = 1;
            $first = ", ";
        }
        if ($marker) return $timesince;
        if($hours=floor($totaldelay/3600))
        {
            $totaldelay = $totaldelay % 3600;
            $plural = '';
            if ($hours > 1) $plural='s';
            $interval = $hours." hour".$plural;
            $timesince = $timesince.$first.$interval;
            if ($marker) return $timesince;
            $marker = 1;
            $first = ", ";

        }
        if($minutes=floor($totaldelay/60))
        {
            $totaldelay = $totaldelay % 60;
            $plural = '';
            if ($minutes > 1) $plural='s';
            $interval = $minutes." minute".$plural;
            $timesince = $timesince.$first.$interval;
            if ($marker) return $timesince;
            $first = ", ";
        }
        if($seconds=floor($totaldelay/1))
        {
            $totaldelay = $totaldelay % 1;
            $plural = '';
            if ($seconds > 1) $plural='s';
            $interval = $seconds." second".$plural;
            $timesince = $timesince.$first.$interval;
        }        
        return $timesince;

    }
}

How to create a 100% screen width div inside a container in bootstrap?

2019's answer as this is still actively seen today

You should likely change the .container to .container-fluid, which will cause your container to stretch the entire screen. This will allow any div's inside of it to naturally stretch as wide as they need.

original hack from 2015 that still works in some situations

You should pull that div outside of the container. You're asking a div to stretch wider than its parent, which is generally not recommended practice.

If you cannot pull it out of the div for some reason, you should change the position style with this css:

.full-width-div {
    position: absolute;
    width: 100%;
    left: 0;
}

Instead of absolute, you could also use fixed, but then it will not move as you scroll.

HQL ERROR: Path expected for join

You need to name the entity that holds the association to User. For example,

... INNER JOIN ug.user u ...

That's the "path" the error message is complaining about -- path from UserGroup to User entity.

Hibernate relies on declarative JOINs, for which the join condition is declared in the mapping metadata. This is why it is impossible to construct the native SQL query without having the path.

Remove a file from a Git repository without deleting it from the local filesystem

As per my Answer here: https://stackoverflow.com/questions/6313126/how-to-remove-a-directory-in-my-github-repository

To remove folder/directory or file only from git repository and not from the local try 3 simple steps.


Steps to remove directory

git rm -r --cached File-or-FolderName
git commit -m "Removed folder from repository"
git push origin master

Steps to ignore that folder in next commits

To ignore that folder from next commits make one file in root named .gitignore and put that folders name into it. You can put as many as you want

.gitignore file will be look like this

/FolderName

remove directory

Overflow:hidden dots at the end

Hopefully it's helpful for you:

_x000D_
_x000D_
.text-with-dots {_x000D_
    display: block;_x000D_
    max-width: 98%;_x000D_
    white-space: nowrap;_x000D_
    overflow: hidden !important;_x000D_
    text-overflow: ellipsis;_x000D_
}
_x000D_
<div class='text-with-dots'>Some texts here Some texts here Some texts here Some texts here Some texts here Some texts here </div>
_x000D_
_x000D_
_x000D_

Generate HTML table from 2D JavaScript array

Here is an example of how you can generate and read data from a matrix m x n... in JavaScript

let createMatrix = (m, n) => {
      let [row, column] = [[], []],
          rowColumn = m * n
      for (let i = 1; i <= rowColumn; i++) {
        column.push(i)
        if (i % n === 0) {
          row.push(column)
          column = []
        }
      }
      return row
    }

let setColorForEachElement = (matrix, colors) => {
  let row = matrix.map(row => {
    let column = row.map((column, key) => {
      return { number: column, color: colors[key] }
    })
    return column
  })
  return row
} 

const colors = ['red', 'green', 'blue', 'purple', 'brown', 'yellow', 'orange', 'grey']
const matrix = createMatrix(6, 8)
const colorApi = setColorForEachElement(matrix, colors)

let table ='<table>'
colorApi.forEach(row => {
  table+= '<tr>'
    row.forEach(column =>  table += `<td style='background: ${column.color};'>${column.number}<td>` )
  table+='</tr>'
})
table+= '</table>'
document.write(table);

Ruby sleep or delay less than a second?

Pass float to sleep, like sleep 0.1

How do I convert special UTF-8 chars to their iso-8859-1 equivalent using javascript?

Actually, everything is typically stored as Unicode of some kind internally, but lets not go into that. I'm assuming you're getting the iconic "åäö" type strings because you're using an ISO-8859 as your character encoding. There's a trick you can do to convert those characters. The escape and unescape functions used for encoding and decoding query strings are defined for ISO characters, whereas the newer encodeURIComponent and decodeURIComponent which do the same thing, are defined for UTF8 characters.

escape encodes extended ISO-8859-1 characters (UTF code points U+0080-U+00ff) as %xx (two-digit hex) whereas it encodes UTF codepoints U+0100 and above as %uxxxx (%u followed by four-digit hex.) For example, escape("å") == "%E5" and escape("?") == "%u3042".

encodeURIComponent percent-encodes extended characters as a UTF8 byte sequence. For example, encodeURIComponent("å") == "%C3%A5" and encodeURIComponent("?") == "%E3%81%82".

So you can do:

fixedstring = decodeURIComponent(escape(utfstring));

For example, an incorrectly encoded character "å" becomes "Ã¥". The command does escape("Ã¥") == "%C3%A5" which is the two incorrect ISO characters encoded as single bytes. Then decodeURIComponent("%C3%A5") == "å", where the two percent-encoded bytes are being interpreted as a UTF8 sequence.

If you'd need to do the reverse for some reason, that works too:

utfstring = unescape(encodeURIComponent(originalstring));

Is there a way to differentiate between bad UTF8 strings and ISO strings? Turns out there is. The decodeURIComponent function used above will throw an error if given a malformed encoded sequence. We can use this to detect with a great probability whether our string is UTF8 or ISO.

var fixedstring;

try{
    // If the string is UTF-8, this will work and not throw an error.
    fixedstring=decodeURIComponent(escape(badstring));
}catch(e){
    // If it isn't, an error will be thrown, and we can assume that we have an ISO string.
    fixedstring=badstring;
}

Launch custom android application from android browser

Hey I got the solution. I did not set the category as "Default". Also I was using the Main activity for the intent Data. Now i am using a different activity for the intent data. Thanks for the help. :)

Case-insensitive search in Rails model

Case-insensitive searching comes built-in with Rails. It accounts for differences in database implementations. Use either the built-in Arel library, or a gem like Squeel.

Working with a List of Lists in Java

 public class TEst {

    public static void main(String[] args) {

        List<Integer> ls=new ArrayList<>();
        ls.add(1);
        ls.add(2);
        List<Integer> ls1=new ArrayList<>();
        ls1.add(3);
        ls1.add(4);
        List<List<Integer>> ls2=new ArrayList<>();
        ls2.add(ls);
        ls2.add(ls1);

        List<List<List<Integer>>> ls3=new ArrayList<>();
        ls3.add(ls2);


        methodRecursion(ls3);
    }

    private static void methodRecursion(List ls3) {
        for(Object ls4:ls3)
        {
             if(ls4 instanceof List)    
             {
                methodRecursion((List)ls4);
             }else {
                 System.out.print(ls4);
             }

        }
    }

}

Display number always with 2 decimal places in <input>

Simply use the number pipe like so :

{{ numberValue | number : '.2-2'}}

The pipe above works as follows :

  • Show at-least 1 integer digit before decimal point, set by default
  • Show not less 2 integer digits after the decimal point
  • Show not more than 2 integer digits after the decimal point

configure Git to accept a particular self-signed server certificate for a particular https remote

On windows in a corporate environment where certificates are distributed from a single source, I found this answer solved the issue: https://stackoverflow.com/a/48212753/761755

Dividing two integers to produce a float result

Cast the operands to floats:

float ans = (float)a / (float)b;

Using group by and having clause

The semantics of Having

To better understand having, you need to see it from a theoretical point of view.

A group by is a query that takes a table and summarizes it into another table. You summarize the original table by grouping the original table into subsets (based upon the attributes that you specify in the group by). Each of these groups will yield one tuple.

The Having is simply equivalent to a WHERE clause after the group by has executed and before the select part of the query is computed.

Lets say your query is:

select a, b, count(*) 
from Table 
where c > 100 
group by a, b 
having count(*) > 10;

The evaluation of this query can be seen as the following steps:

  1. Perform the WHERE, eliminating rows that do not satisfy it.
  2. Group the table into subsets based upon the values of a and b (each tuple in each subset has the same values of a and b).
  3. Eliminate subsets that do not satisfy the HAVING condition
  4. Process each subset outputting the values as indicated in the SELECT part of the query. This creates one output tuple per subset left after step 3.

You can extend this to any complex query there Table can be any complex query that return a table (a cross product, a join, a UNION, etc).

In fact, having is syntactic sugar and does not extend the power of SQL. Any given query:

SELECT list 
FROM table
GROUP BY attrList
HAVING condition;

can be rewritten as:

SELECT list from (
   SELECT listatt 
   FROM table 
   GROUP BY attrList) as Name
WHERE condition;

The listatt is a list that includes the GROUP BY attributes and the expressions used in list and condition. It might be necessary to name some expressions in this list (with AS). For instance, the example query above can be rewritten as:

select a, b, count 
from (select a, b, count(*) as count
      from Table 
      where c > 100
      group by a, b) as someName
where count > 10;

The solution you need

Your solution seems to be correct:

SELECT s.sid, s.name
FROM Supplier s, Supplies su, Project pr
WHERE s.sid = su.sid AND su.jid = pr.jid
GROUP BY s.sid, s.name
HAVING COUNT (DISTINCT pr.jid) >= 2 

You join the three tables, then using sid as a grouping attribute (sname is functionally dependent on it, so it does not have an impact on the number of groups, but you must include it, otherwise it cannot be part of the select part of the statement). Then you are removing those that do not satisfy your condition: the satisfy pr.jid is >= 2, which is that you wanted originally.

Best solution to your problem

I personally prefer a simpler cleaner solution:

  1. You need to only group by Supplies (sid, pid, jid**, quantity) to find the sid of those that supply at least to two projects.
  2. Then join it to the Suppliers table to get the supplier same.

 SELECT sid, sname from
    (SELECT sid from supplies 
    GROUP BY sid, pid 
    HAVING count(DISTINCT jid) >= 2
    ) AS T1
NATURAL JOIN 
Supliers;

It will also be faster to execute, because the join is only done when needed, not all the times.

--dmg

How to hide/show div tags using JavaScript?

You can Hide/Show Div using Js function. sample below

   <script>
        function showDivAttid(){

            if(Your Condition)
            {
             document.getElementById("attid").style.display = 'inline';
            }
            else
            {
            document.getElementById("attid").style.display = 'none';
            }

        }

    </script>

HTML - Show/Hide this text

Best way to store data locally in .NET (C#)

A fourth option to those you mention are binary files. Although that sounds arcane and difficult, it's really easy with the serialization API in .NET.

Whether you choose binary or XML files, you can use the same serialization API, although you would use different serializers.

To binary serialize a class, it must be marked with the [Serializable] attribute or implement ISerializable.

You can do something similar with XML, although there the interface is called IXmlSerializable, and the attributes are [XmlRoot] and other attributes in the System.Xml.Serialization namespace.

If you want to use a relational database, SQL Server Compact Edition is free and very lightweight and based on a single file.

Get int from String, also containing letters, in Java

You can also use Scanner :

Scanner s = new Scanner(MyString);
s.nextInt();

Redirect echo output in shell script to logfile

I tried to manage using the below command. This will write the output in log file as well as print on console.

#!/bin/bash

# Log Location on Server.
LOG_LOCATION=/home/user/scripts/logs
exec > >(tee -i $LOG_LOCATION/MylogFile.log)
exec 2>&1

echo "Log Location should be: [ $LOG_LOCATION ]"

Please note: This is bash code so if you run it using sh it will through syntax error

Path.Combine for URLs?

Witty example, Ryan, to end with a link to the function. Well done.

One recommendation Brian: if you wrap this code in a function, you may want to use a UriBuilder to wrap the base URL prior to the TryCreate call.

Otherwise, the base URL MUST include the scheme (where the UriBuilder will assume http://). Just a thought:

public string CombineUrl(string baseUrl, string relativeUrl) {
    UriBuilder baseUri = new UriBuilder(baseUrl);
    Uri newUri;

    if (Uri.TryCreate(baseUri.Uri, relativeUrl, out newUri))
        return newUri.ToString();
    else
        throw new ArgumentException("Unable to combine specified url values");
}

What is the apply function in Scala?

TLDR for people comming from c++

It's just overloaded operator of ( ) parentheses

So in scala:

class X {
   def apply(param1: Int, param2: Int, param3: Int) : Int = {
     // Do something
   }
}

Is same as this in c++:

class X {
   int operator()(int param1, int param2, int param3) {
      // do something
   }
};

Is there any way to kill a Thread?

You should never forcibly kill a thread without cooperating with it.

Killing a thread removes any guarantees that try/finally blocks set up so you might leave locks locked, files open, etc.

The only time you can argue that forcibly killing threads is a good idea is to kill a program fast, but never single threads.

How do I get the title of the current active window using c#?

If it happens that you need the Current Active Form from your MDI application: (MDI- Multi Document Interface).

Form activForm;
activForm = Form.ActiveForm.ActiveMdiChild;

copy db file with adb pull results in 'permission denied' error

This answer ended up working for me: https://stackoverflow.com/a/15559278/53001

Backup to a file, pull the backup, and then convert it to a tarball and extract it.

adb backup  -f myAndroidBackup.ab  com.corp.appName

dd if=myAndroidBackup.ab bs=1 skip=24 | python -c "import zlib,sys;sys.stdout.write(zlib.decompress(sys.stdin.read()))" | tar -xvf - 

Check if a value is an object in JavaScript

const isObject = function(obj) {
  const type = typeof obj;
  return type === 'function' || type === 'object' && !!obj;
};

!!obj is shorthand for checking if obj is truthy (to filter out null)

Copy mysql database from remote server to local computer

Often our databases are really big and the take time to take dump directly from remote machine to other machine as our friends other have suggested above.

In such cases what you can do is to take the dump on remote machine using MYSQLDUMP Command

MYSQLDUMP -uuser -p --all-databases > file_name.sql

and than transfer that file from remote server to your machine using Linux SCP Command

scp user@remote_ip:~/mysql_dump_file_name.sql ./

Angular 2 - View not updating after model changes

In my case, I had a very similar problem. I was updating my view inside a function that was being called by a parent component, and in my parent component I forgot to use @ViewChild(NameOfMyChieldComponent). I lost at least 3 hours just for this stupid mistake. i.e: I didn't need to use any of those methods:

  • ChangeDetectorRef.detectChanges()
  • ChangeDetectorRef.markForCheck()
  • ApplicationRef.tick()

How to .gitignore all files/folder in a folder, but not the folder itself?

Put this .gitignore into the folder, then git add .gitignore.

*
*/
!.gitignore

The * line tells git to ignore all files in the folder, but !.gitignore tells git to still include the .gitignore file. This way, your local repository and any other clones of the repository all get both the empty folder and the .gitignore it needs.

Edit: May be obvious but also add */ to the .gitignore to also ignore subfolders.

How to set a variable to current date and date-1 in linux?

simple:

today="$(date '+%Y-%m-%d')"
yesterday="$(date -d yesterday '+%Y-%m-%d')"

What does the shrink-to-fit viewport meta attribute do?

It is Safari specific, at least at time of writing, being introduced in Safari 9.0. From the "What's new in Safari?" documentation for Safari 9.0:

Viewport Changes

Viewport meta tags using "width=device-width" cause the page to scale down to fit content that overflows the viewport bounds. You can override this behavior by adding "shrink-to-fit=no" to your meta tag as shown below. The added value will prevent the page from scaling to fit the viewport.

<meta name="viewport" content="width=device-width, initial-scale=1.0, shrink-to-fit=no">

In short, adding this to the viewport meta tag restores pre-Safari 9.0 behaviour.

Example

Here's a worked visual example which shows the difference upon loading the page in the two configurations.

The red section is the width of the viewport and the blue section is positioned outside the initial viewport (eg left: 100vw). Note how in the first example the page is zoomed to fit when shrink-to-fit=no is omitted (thus showing the out-of-viewport content) and the blue content remains off screen in the latter example.

The code for this example can be found at https://codepen.io/davidjb/pen/ENGqpv.

Without shrink-to-fit specified

Without shrink-to-fit=no

With shrink-to-fit=no

With shrink-to-fit=no

mvn command is not recognized as an internal or external command

Try setting the path of maven first through command prompt.

setpath.bat Open the cmd from the base window of the batch file.

The rest maven commands can be used once path is set through cmd.

What is the meaning of {...this.props} in Reactjs

It will compile to this:

React.createElement('div', this.props, 'Content Here');

As you can see above, it passes all it's props to the div.

Create Windows service from executable

To create a Windows Service from an executable, you can use sc.exe:

sc.exe create <new_service_name> binPath= "<path_to_the_service_executable>"

You must have quotation marks around the actual exe path, and a space after the binPath=.

More information on the sc command can be found in Microsoft KB251192.

Note that it will not work for just any executable: the executable must be a Windows Service (i.e. implement ServiceMain). When registering a non-service executable as a service, you'll get the following error upon trying to start the service:

Error 1053: The service did not respond to the start or control request in a timely fashion.

There are tools that can create a Windows Service from arbitrary, non-service executables, see the other answers for examples of such tools.

What is the difference between Scala's case class and class?

Nobody mentioned that case class companion object has tupled defention, which has a type:

case class Person(name: String, age: Int)
//Person.tupled is def tupled: ((String, Int)) => Person

The only use case I can find is when you need to construct case class from tuple, example:

val bobAsTuple = ("bob", 14)
val bob = (Person.apply _).tupled(bobAsTuple) //bob: Person = Person(bob,14)

You can do the same, without tupled, by creating object directly, but if your datasets expressed as list of tuple with arity 20(tuple with 20 elements), may be using tupled is your choise.

PHP/regex: How to get the string value of HTML tag?

this might be old but my answer might help someone

You can simply use

$str = '<textformat leading="2"><p align="left"><font size="10">get me</font></p></textformat>';
echo strip_tags($str);

https://www.php.net/manual/en/function.strip-tags.php

Android Studio cannot resolve R in imported project?

File -> invalidate caches

then

Restart application

What is the purpose of "pip install --user ..."?

Just a warning:

According to this issue, --user is currently not valid inside a virtual env's pip, since a user location doesn't really make sense for a virtual environment.

So do not use pip install --user some_pkg inside a virtual environment, otherwise, virtual environment's pip will be confused. See this answer for more details.

org.apache.catalina.LifecycleException: Failed to start component [StandardServer[8005]]A child container failed during start

Go to the task manager, kill the java processes and turn the server back on. should work fine.

How To Set A JS object property name from a variable

jsonVariable = {}
for(i=1; i<3; i++) {        
   var jsonKey  = i+'name';
   jsonVariable[jsonKey] = 'name1'
}

this will be similar to

    jsonVariable = {
    1name : 'name1'
    2name : 'name1'
}

Currency formatting in Python

Oh, that's an interesting beast.

I've spent considerable time of getting that right, there are three main issues that differs from locale to locale: - currency symbol and direction - thousand separator - decimal point

I've written my own rather extensive implementation of this which is part of the kiwi python framework, check out the LGPL:ed source here:

http://svn.async.com.br/cgi-bin/viewvc.cgi/kiwi/trunk/kiwi/currency.py?view=markup

The code is slightly Linux/Glibc specific, but shouldn't be too difficult to adopt to windows or other unixes.

Once you have that installed you can do the following:

>>> from kiwi.datatypes import currency
>>> v = currency('10.5').format()

Which will then give you:

'$10.50'

or

'10,50 kr'

Depending on the currently selected locale.

The main point this post has over the other is that it will work with older versions of python. locale.currency was introduced in python 2.5.

What is the best way to test for an empty string with jquery-out-of-the-box?

Since you can also input numbers as well as fixed type strings, the answer should actually be:

function isBlank(value) {
  return $.trim(value);
}

Prevent browser caching of AJAX call result

A small addition to the excellent answers given: If you're running with a non-ajax backup solution for users without javascript, you will have to get those server-side headers correct anyway. This is not impossible, although I understand those that give it up ;)

I'm sure there's another question on SO that will give you the full set of headers that are appropriate. I am not entirely conviced miceus reply covers all the bases 100%.

Clearing the terminal screen?

I have found that ASCII 12 make a Form feed, that is a new page. here is a wikipedia definition

"Form feed is a page-breaking ASCII control character. It forces the printer to eject the current page and to continue printing at the top of another"

The code is

Serial.write(12);

Arduino Terminate doesn't support the character but Putty a light open source telnet client can do it

An Example of the code

void setup() {
  Serial.begin(9600);//Initializase the serial transmiter speed

}

void loop() {
    //Code tested with Putty terminal

    Serial.write(12);//ASCII for a Form feed
    Serial.println("This is the title of a new page");// your code

    delay(500);//delay for visual
    }

How to import multiple csv files in a single load?

val df = spark.read.option("header", "true").csv("C:spark\\sample_data\\*.csv)

will consider files tmp, tmp1, tmp2, ....

How to detect if JavaScript is disabled?

This is what worked for me: it redirects a visitor if javascript is disabled

<noscript><meta http-equiv="refresh" content="0; url=whatyouwant.html" /></noscript>

What's the difference between HTML 'hidden' and 'aria-hidden' attributes?

setting aria-hidden to false and toggling it on element.show() worked for me.

e.g

<span aria-hidden="true">aria text</span>

$(span).attr('aria-hidden', 'false');
$(span).show();

and when hiding back

$(span).attr('aria-hidden', 'true');
$(span).hide();

Use a normal link to submit a form

You can't really do this without some form of scripting to the best of my knowledge.

<form id="my_form">
<!-- Your Form -->    
<a href="javascript:{}" onclick="document.getElementById('my_form').submit(); return false;">submit</a>
</form>

Example from Here.

Preloading @font-face fonts?

Since 2017 you have preload

MDN: The preload value of the element's rel attribute allows you to write declarative fetch requests in your HTML , specifying resources that your pages will need very soon after loading, which you therefore want to start preloading early in the lifecycle of a page load, before the browser's main rendering machinery kicks in. This ensures that they are made available earlier and are less likely to block the page's first render, leading to performance improvements.

<link rel="preload" href="/fonts/myfont.eot" as="font" crossorigin="anonymous" />

Always check browser compatibility.

It is most useful for font preloading (not waiting for the browser to find it in some CSS). You can also preload some logos, icons and scripts.

Ng-model does not update controller value

"If you use ng-model, you have to have a dot in there."
Make your model point to an object.property and you'll be good to go.

Controller

$scope.formData = {};
$scope.check = function () {
  console.log($scope.formData.searchText.$modelValue); //works
}

Template

<input ng-model="formData.searchText"/>
<button ng-click="check()">Check!</button>

This happens when child scopes are in play - like child routes or ng-repeats. The child-scope creates it's own value and a name conflict is born as illustrated here:

See this video clip for more: https://www.youtube.com/watch?v=SBwoFkRjZvE&t=3m15s

regular expression: match any word until first space

for the entire line

^(\w+)\s+(\w+)\s+(\d+(?:\/\d+){2})\s+(\w+)$

IIS Request Timeout on long ASP.NET operation

Remove ~ character in location so

path="~/Admin/SomePage.aspx"

becomes

path="Admin/SomePage.aspx"

Depend on a branch or tag using a git URL in a package.json?

per @dantheta's comment:

As of npm 1.1.65, Github URL can be more concise user/project. npmjs.org/doc/files/package.json.html You can attach the branch like user/project#branch

So

"babel-eslint": "babel/babel-eslint",

Or for tag v1.12.0 on jscs:

"jscs": "jscs-dev/node-jscs#v1.12.0",

Note, if you use npm --save, you'll get the longer git

From https://docs.npmjs.com/cli/v6/configuring-npm/package-json#git-urls-as-dependencies

Git URLs as Dependencies

Git urls are of the form:

git+ssh://[email protected]:npm/cli.git#v1.0.27 git+ssh://[email protected]:npm/cli#semver:^5.0 git+https://[email protected]/npm/cli.git
git://github.com/npm/cli.git#v1.0.27

If #<commit-ish> is provided, it will be used to clone exactly that commit. If > the commit-ish has the format #semver:<semver>, <semver> can be any valid semver range or exact version, and npm will look for any tags or refs matching that range in the remote repository, much as it would for a registry dependency. If neither #<commit-ish> or #semver:<semver> is specified, then master is used.

GitHub URLs

As of version 1.1.65, you can refer to GitHub urls as just "foo": "user/foo-project". Just as with git URLs, a commit-ish suffix can be included. For example:

{
 "name": "foo",
 "version": "0.0.0",
 "dependencies": {
   "express": "expressjs/express",
   "mocha": "mochajs/mocha#4727d357ea",
   "module": "user/repo#feature\/branch"
 }
}```

What is uintptr_t data type

It's an unsigned integer type exactly the size of a pointer. Whenever you need to do something unusual with a pointer - like for example invert all bits (don't ask why) you cast it to uintptr_t and manipulate it as a usual integer number, then cast back.

Load image with jQuery and append it to the DOM

With jQuery 3.x use something like:

$('<img src="'+ imgPath +'">').on('load', function() {
  $(this).width(some).height(some).appendTo('#some_target');
});

If input field is empty, disable submit button

For those that use coffeescript, I've put the code we use globally to disable the submit buttons on our most widely used form. An adaption of Adil's answer above.

$('#new_post button').prop 'disabled', true
$('#new_post #post_message').keyup ->
    $('#new_post button').prop 'disabled', if @value == '' then true else false
    return

How to make an ng-click event conditional?

We can add ng-click event conditionally without using disabled class.

HTML:

<div ng-repeat="object in objects">
<span ng-click="!object.status && disableIt(object)">{{object.value}}</span>
</div>

Python: slicing a multi-dimensional array

If you use numpy, this is easy:

slice = arr[:2,:2]

or if you want the 0's,

slice = arr[0:2,0:2]

You'll get the same result.

*note that slice is actually the name of a builtin-type. Generally, I would advise giving your object a different "name".


Another way, if you're working with lists of lists*:

slice = [arr[i][0:2] for i in range(0,2)]

(Note that the 0's here are unnecessary: [arr[i][:2] for i in range(2)] would also work.).

What I did here is that I take each desired row 1 at a time (arr[i]). I then slice the columns I want out of that row and add it to the list that I'm building.

If you naively try: arr[0:2] You get the first 2 rows which if you then slice again arr[0:2][0:2], you're just slicing the first two rows over again.

*This actually works for numpy arrays too, but it will be slow compared to the "native" solution I posted above.

Generate sha256 with OpenSSL and C++

I think that you only have to replace SHA1 function with SHA256 function with tatk code from link in Your post

Jackson and generic type reference

This is a well-known problem with Java type erasure: T is just a type variable, and you must indicate actual class, usually as Class argument. Without such information, best that can be done is to use bounds; and plain T is roughly same as 'T extends Object'. And Jackson will then bind JSON Objects as Maps.

In this case, tester method needs to have access to Class, and you can construct

JavaType type = mapper.getTypeFactory().
  constructCollectionType(List.class, Foo.class)

and then

List<Foo> list = mapper.readValue(new File("input.json"), type);

bash, extract string before a colon

This works for me you guys can try it out

INPUT='ubuntu:x:1000:1000:Ubuntu:/home/ubuntu:/bin/bash'
SUBSTRING=$(echo $INPUT| cut -d: -f1)
echo $SUBSTRING

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

Go to your Info.plist and add two Keys:

Go to your Info.plist and add two Keys:

How to run a Python script in the background even after I logout SSH?

If you've already started the process, and don't want to kill it and restart under nohup, you can send it to the background, then disown it.

Ctrl+Z (suspend the process)

bg (restart the process in the background

disown %1 (assuming this is job #1, use jobs to determine)

MySQL Multiple Joins in one query?

Multi joins in SQL work by progressively creating derived tables one after the other. See this link explaining the process:

https://www.interfacett.com/blogs/multiple-joins-work-just-like-single-joins/

referenced before assignment error in python

My Scenario

def example():
    cl = [0, 1]
    def inner():
        #cl = [1, 2] # access this way will throw `reference before assignment`
        cl[0] = 1 
        cl[1] = 2   # these won't

    inner()

Multiple radio button groups in MVC 4 Razor

all you need is to tie the group to a different item in your model

@Html.RadioButtonFor(x => x.Field1, "Milk")
@Html.RadioButtonFor(x => x.Field1, "Butter")

@Html.RadioButtonFor(x => x.Field2, "Water")
@Html.RadioButtonFor(x => x.Field2, "Beer")

2 ways for "ClearContents" on VBA Excel, but 1 work fine. Why?

For numerical addressing of cells try to enable S1O1 checkbox in MS Excel settings. It is the second tab from top (i.e. Formulas), somewhere mid-page in my Hungarian version.

If enabled, it handles VBA addressing in both styles, i.e. Range("A1:B10") and Range(Cells(1, 1), Cells(10, 2)). I assume it handles Range("A1:B10") style only, if not enabled.

Good luck!

(Note, that Range("A1:B10") represents a 2x10 square, while Range(Cells(1, 1), Cells(10, 2)) represents 10x2. Using column numbers instead of letters will not affect the order of addresing.)

How to check if "Radiobutton" is checked?

If you need for espresso test the solutions is like this :

onView(withId(id)).check(matches(isChecked()));

Bye,

GIT commit as different user without email / or only email

An alternative if the concern is to hide the real email address...If you are committing to Github you don't need a real email you can use <username>@users.noreply.github.com

Regardless of using Github or not, you probably first want change your committer details (on windows use SET GIT_...)

GIT_COMMITTER_NAME='username' 
GIT_COMMITTER_EMAIL='[email protected]'

Then set the author

git commit --author="username <[email protected]>"

https://help.github.com/articles/keeping-your-email-address-private

How to bind multiple values to a single WPF TextBlock?

Use a ValueConverter

[ValueConversion(typeof(string), typeof(String))]
public class MyConverter: IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return string.Format("{0}:{1}", (string) value, (string) parameter);
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {

        return DependencyProperty.UnsetValue;
    }
}

and in the markup

<src:MyConverter x:Key="MyConverter"/>

. . .

<TextBlock Text="{Binding Name, Converter={StaticResource MyConverter Parameter=ID}}" />

Initialize a string variable in Python: "" or None?

Python philosophy is to be readable.
That's why it's good practice to define your attributes in __init__() even if it's optional.
In the same spirit, you have to ask yourself what clearer for anyone who reads your code. In fact the type itself give much information about future use of your variable. So:

kind = None

Is syntaxically correct, but reader does not know much. Is it a string, a code as integer, a list, etc. ?

kind_str = None
kind = ""

Both say a little more, the first has the type in its name and the second in its declaration. I would go for the second, neater.

jQuery If DIV Doesn't Have Class "x"

$(".thumbs").hover(
    function(){
        if (!$(this).hasClass("selected")) {
            $(this).stop().fadeTo("normal", 1.0);
        }
    },
    function(){
        if (!$(this).hasClass("selected")) {
            $(this).stop().fadeTo("slow", 0.3); 
        }           
    }
);

Putting an if inside of each part of the hover will allow you to change the select class dynamically and the hover will still work.

$(".thumbs").click(function() {
    $(".thumbs").each(function () {
        if ($(this).hasClass("selected")) {
            $(this).removeClass("selected");
            $(this).hover();
        }
    });                 
    $(this).addClass("selected");                   
});

As an example I've also attached a click handler to switch the selected class to the clicked item. Then I fire the hover event on the previous item to make it fade out.

JavaScript TypeError: Cannot read property 'style' of null

simply I think you are missing a single quote in your code

if ((hr==20)) document.write("Good Night"); document.getElementById('Night"here").style.display=''

it should be like this

if ((hr==20)) document.write("Good Night"); document.getElementById('Night').style.display=''

How to sum data.frame column values?

To sum values in data.frame you first need to extract them as a vector.

There are several way to do it:

# $ operatior
x <- people$Weight
x
# [1] 65 70 64

Or using [, ] similar to matrix:

x <- people[, 'Weight']
x
# [1] 65 70 64

Once you have the vector you can use any vector-to-scalar function to aggregate the result:

sum(people[, 'Weight'])
# [1] 199

If you have NA values in your data, you should specify na.rm parameter:

sum(people[, 'Weight'], na.rm = TRUE)

How to get `DOM Element` in Angular 2?

Use ViewChild with #localvariable as shown here,

<textarea  #someVar  id="tasknote"
                  name="tasknote"
                  [(ngModel)]="taskNote"
                  placeholder="{{ notePlaceholder }}"
                  style="background-color: pink"
                  (blur)="updateNote() ; noteEditMode = false " (click)="noteEditMode = false"> {{ todo.note }} 

</textarea>

In component,

OLDEST Way

import {ElementRef} from '@angular/core';
@ViewChild('someVar') el:ElementRef;

ngAfterViewInit()
{
   this.el.nativeElement.focus();
}


OLD Way

import {ElementRef} from '@angular/core';
@ViewChild('someVar') el:ElementRef;

constructor(private rd: Renderer) {}
ngAfterViewInit() {
    this.rd.invokeElementMethod(this.el.nativeElement,'focus');
}


Updated on 22/03(March)/2017

NEW Way

Please note from Angular v4.0.0-rc.3 (2017-03-10) few things have been changed. Since Angular team will deprecate invokeElementMethod, above code no longer can be used.

BREAKING CHANGES

since 4.0 rc.1:

rename RendererV2 to Renderer2
rename RendererTypeV2 to RendererType2
rename RendererFactoryV2 to RendererFactory2

import {ElementRef,Renderer2} from '@angular/core';
@ViewChild('someVar') el:ElementRef;

constructor(private rd: Renderer2) {}

ngAfterViewInit() {
      console.log(this.rd); 
      this.el.nativeElement.focus();      //<<<=====same as oldest way
}

console.log(this.rd) will give you following methods and you can see now invokeElementMethod is not there. Attaching img as yet it is not documented.

NOTE: You can use following methods of Rendere2 with/without ViewChild variable to do so many things.

enter image description here

Can't push to GitHub because of large file which I already deleted

The solution to keep the large files/folders within the working folder

This is the line that worked to solve the problem asked here (from answer 1):

git filter-branch --index-filter 'git rm -r --cached --ignore-unmatch <file/dir>' HEAD

This command also delete the file/dir if the file/dir is within the working tree.

If you want to keep the file/folder within the working tree I propose taking the following steps.

  1. After that error run git reset HEAD^
  2. Add the file/folder in question into ``.gitignore``` file.

  3. Proceed as usual git add . which might capture other files/folders but must capture .gitignore file. Next is git commit -m"message" and finally git push origin <branch_name>

How can I check if a program exists from a Bash script?

Expanding on @lhunath's and @GregV's answers, here's the code for the people who want to easily put that check inside an if statement:

exists()
{
  command -v "$1" >/dev/null 2>&1
}

Here's how to use it:

if exists bash; then
  echo 'Bash exists!'
else
  echo 'Your system does not have Bash'
fi

Error:(9, 5) error: resource android:attr/dialogCornerRadius not found

If you are migrated for AndroidX and getting this error, you need to set the compile SDK to Android 9.0 (API level 28) or higher

How to communicate between iframe and the parent site?

You can also use

postMessage(message, '*');

How to execute IN() SQL queries with Spring's JDBCTemplate effectively?

Refer to here

write query with named parameter, use simple ListPreparedStatementSetter with all parameters in sequence. Just add below snippet to convert the query in traditional form based to available parameters,

ParsedSql parsedSql = NamedParameterUtils.parseSqlStatement(namedSql);

List<Integer> parameters = new ArrayList<Integer>();
for (A a : paramBeans)
    parameters.add(a.getId());

MapSqlParameterSource parameterSource = new MapSqlParameterSource();
parameterSource.addValue("placeholder1", parameters);
// create SQL with ?'s
String sql = NamedParameterUtils.substituteNamedParameters(parsedSql, parameterSource);     
return sql;

How to check for a JSON response using RSpec?

You can examine the response object and verify that it contains the expected value:

@expected = { 
        :flashcard  => @flashcard,
        :lesson     => @lesson,
        :success    => true
}.to_json
get :action # replace with action name / params as necessary
response.body.should == @expected

EDIT

Changing this to a post makes it a bit trickier. Here's a way to handle it:

 it "responds with JSON" do
    my_model = stub_model(MyModel,:save=>true)
    MyModel.stub(:new).with({'these' => 'params'}) { my_model }
    post :create, :my_model => {'these' => 'params'}, :format => :json
    response.body.should == my_model.to_json
  end

Note that mock_model will not respond to to_json, so either stub_model or a real model instance is needed.

RecyclerView - How to smooth scroll to top of item on a certain position?

You can reverse your list by list.reverse() and finaly call RecylerView.scrollToPosition(0)

    list.reverse()
    layout = LinearLayoutManager(this,LinearLayoutManager.VERTICAL,true)  
    RecylerView.scrollToPosition(0)

Why is ZoneOffset.UTC != ZoneId.of("UTC")?

The answer comes from the javadoc of ZoneId (emphasis mine) ...

A ZoneId is used to identify the rules used to convert between an Instant and a LocalDateTime. There are two distinct types of ID:

  • Fixed offsets - a fully resolved offset from UTC/Greenwich, that uses the same offset for all local date-times
  • Geographical regions - an area where a specific set of rules for finding the offset from UTC/Greenwich apply

Most fixed offsets are represented by ZoneOffset. Calling normalized() on any ZoneId will ensure that a fixed offset ID will be represented as a ZoneOffset.

... and from the javadoc of ZoneId#of (emphasis mine):

This method parses the ID producing a ZoneId or ZoneOffset. A ZoneOffset is returned if the ID is 'Z', or starts with '+' or '-'.

The argument id is specified as "UTC", therefore it will return a ZoneId with an offset, which also presented in the string form:

System.out.println(now.withZoneSameInstant(ZoneOffset.UTC));
System.out.println(now.withZoneSameInstant(ZoneId.of("UTC")));

Outputs:

2017-03-10T08:06:28.045Z
2017-03-10T08:06:28.045Z[UTC]

As you use the equals method for comparison, you check for object equivalence. Because of the described difference, the result of the evaluation is false.

When the normalized() method is used as proposed in the documentation, the comparison using equals will return true, as normalized() will return the corresponding ZoneOffset:

Normalizes the time-zone ID, returning a ZoneOffset where possible.

now.withZoneSameInstant(ZoneOffset.UTC)
    .equals(now.withZoneSameInstant(ZoneId.of("UTC").normalized())); // true

As the documentation states, if you use "Z" or "+0" as input id, of will return the ZoneOffset directly and there is no need to call normalized():

now.withZoneSameInstant(ZoneOffset.UTC).equals(now.withZoneSameInstant(ZoneId.of("Z"))); //true
now.withZoneSameInstant(ZoneOffset.UTC).equals(now.withZoneSameInstant(ZoneId.of("+0"))); //true

To check if they store the same date time, you can use the isEqual method instead:

now.withZoneSameInstant(ZoneOffset.UTC)
    .isEqual(now.withZoneSameInstant(ZoneId.of("UTC"))); // true

Sample

System.out.println("equals - ZoneId.of(\"UTC\"): " + nowZoneOffset
        .equals(now.withZoneSameInstant(ZoneId.of("UTC"))));
System.out.println("equals - ZoneId.of(\"UTC\").normalized(): " + nowZoneOffset
        .equals(now.withZoneSameInstant(ZoneId.of("UTC").normalized())));
System.out.println("equals - ZoneId.of(\"Z\"): " + nowZoneOffset
        .equals(now.withZoneSameInstant(ZoneId.of("Z"))));
System.out.println("equals - ZoneId.of(\"+0\"): " + nowZoneOffset
        .equals(now.withZoneSameInstant(ZoneId.of("+0"))));
System.out.println("isEqual - ZoneId.of(\"UTC\"): "+ nowZoneOffset
        .isEqual(now.withZoneSameInstant(ZoneId.of("UTC"))));

Output:

equals - ZoneId.of("UTC"): false
equals - ZoneId.of("UTC").normalized(): true
equals - ZoneId.of("Z"): true
equals - ZoneId.of("+0"): true
isEqual - ZoneId.of("UTC"): true

How do I convert struct System.Byte byte[] to a System.IO.Stream object in C#?

You're looking for the MemoryStream.Write method.

For example, the following code will write the contents of a byte[] array into a memory stream:

byte[] myByteArray = new byte[10];
MemoryStream stream = new MemoryStream();
stream.Write(myByteArray, 0, myByteArray.Length);

Alternatively, you could create a new, non-resizable MemoryStream object based on the byte array:

byte[] myByteArray = new byte[10];
MemoryStream stream = new MemoryStream(myByteArray);

Associative arrays in Shell scripts

Another non-bash 4 way.

#!/bin/bash

# A pretend Python dictionary with bash 3 
ARRAY=( "cow:moo"
        "dinosaur:roar"
        "bird:chirp"
        "bash:rock" )

for animal in "${ARRAY[@]}" ; do
    KEY=${animal%%:*}
    VALUE=${animal#*:}
    printf "%s likes to %s.\n" "$KEY" "$VALUE"
done

echo -e "${ARRAY[1]%%:*} is an extinct animal which likes to ${ARRAY[1]#*:}\n"

You could throw an if statement for searching in there as well. if [[ $var =~ /blah/ ]]. or whatever.

Why is Chrome showing a "Please Fill Out this Field" tooltip on empty fields?

As I mentioned in your other question:

The problem to do with that fact, that you invented your own non-standard attributes (which you shouldn't have done in the first place), and now new standardized attributes (or attributes in the process of being standardized) are colliding with them.

The proper solution is to completely remove your invented attributes and replace them with something sensible, for example classes (class="Montantetextfield fieldname-Montante required allow-decimal-values"), or store them in JavaScript:

var validationData = {
  "Montante": {fieldname: "Montante", required: true, allowDecimalValues: true}
}

If the proper solution isn't viable, you'll have to rename them. In that case you should use the prefix data-... because that is reserved by HTML5 for such purposes, and it's less likely to collide with something - but it still could, so you should seriously consider the first solution - even it is more work to change.

Using AND/OR in if else PHP statement

AND and OR are just syntactic sugar for && and ||, like in JavaScript, or other C styled syntax languages.

It appears AND and OR have lower precedence than their C style equivalents.

Definition of "downstream" and "upstream"

When you read in git tag man page:

One important aspect of git is it is distributed, and being distributed largely means there is no inherent "upstream" or "downstream" in the system.

, that simply means there is no absolute upstream repo or downstream repo.
Those notions are always relative between two repos and depends on the way data flows:

If "yourRepo" has declared "otherRepo" as a remote one, then:

  • you are pulling from upstream "otherRepo" ("otherRepo" is "upstream from you", and you are "downstream for otherRepo").
  • you are pushing to upstream ("otherRepo" is still "upstream", where the information now goes back to).

Note the "from" and "for": you are not just "downstream", you are "downstream from/for", hence the relative aspect.


The DVCS (Distributed Version Control System) twist is: you have no idea what downstream actually is, beside your own repo relative to the remote repos you have declared.

  • you know what upstream is (the repos you are pulling from or pushing to)
  • you don't know what downstream is made of (the other repos pulling from or pushing to your repo).

Basically:

In term of "flow of data", your repo is at the bottom ("downstream") of a flow coming from upstream repos ("pull from") and going back to (the same or other) upstream repos ("push to").


You can see an illustration in the git-rebase man page with the paragraph "RECOVERING FROM UPSTREAM REBASE":

It means you are pulling from an "upstream" repo where a rebase took place, and you (the "downstream" repo) is stuck with the consequence (lots of duplicate commits, because the branch rebased upstream recreated the commits of the same branch you have locally).

That is bad because for one "upstream" repo, there can be many downstream repos (i.e. repos pulling from the upstream one, with the rebased branch), all of them having potentially to deal with the duplicate commits.

Again, with the "flow of data" analogy, in a DVCS, one bad command "upstream" can have a "ripple effect" downstream.


Note: this is not limited to data.
It also applies to parameters, as git commands (like the "porcelain" ones) often call internally other git commands (the "plumbing" ones). See rev-parse man page:

Many git porcelainish commands take mixture of flags (i.e. parameters that begin with a dash '-') and parameters meant for the underlying git rev-list command they use internally and flags and parameters for the other commands they use downstream of git rev-list. This command is used to distinguish between them.

How to Allow Remote Access to PostgreSQL database

You have to add this to your pg_hba.conf and restart your PostgreSQL.

host all all 192.168.56.1/24 md5

This works with VirtualBox and host-only adapter enabled. If you don't use Virtualbox you have to replace the IP address.

How to increase an array's length

By definition arrays are fixed size. You can use instead an Arraylist wich is that, a "dynamic size" array. Actually what happens is that the VM "adjust the size"* of the array exposed by the ArrayList.

See also

*using back-copy arrays

Pass a variable to a PHP script running from the command line

Save this code in file myfile.php and run as php myfile.php type=daily

<?php
$a = $argv;
$b = array();
if (count($a) === 1) exit;
foreach ($a as $key => $arg) {
    if ($key > 0) {
        list($x,$y) = explode('=', $arg);
        $b["$x"] = $y;  
    }
}
?>

If you add var_dump($b); before the ?> tag, you will see that the array $b contains type => daily.

Find all CSV files in a directory using Python

import os
import glob

path = 'c:\\'
extension = 'csv'
os.chdir(path)
result = glob.glob('*.{}'.format(extension))
print(result)

How to convert a color integer to a hex String in Android?

String int2string = Integer.toHexString(INTEGERColor); //to ARGB
String HtmlColor = "#"+ int2string.substring(int2string.length() - 6, int2string.length()); // a stupid way to append your color

Elegant way to check for missing packages and install them?

Using lapply family and anonymous function approach you may:

  1. Try to attach all listed packages.
  2. Install missing only (using || lazy evaluation).
  3. Attempt to attach again those were missing in step 1 and installed in step 2.
  4. Print each package final load status (TRUE / FALSE).

    req <- substitute(require(x, character.only = TRUE))
    lbs <- c("plyr", "psych", "tm")
    sapply(lbs, function(x) eval(req) || {install.packages(x); eval(req)})
    
    plyr psych    tm 
    TRUE  TRUE  TRUE 
    

How to get the number of days of difference between two dates on mysql?

Use the DATEDIFF() function.

Example from documentation:

SELECT DATEDIFF('2007-12-31 23:59:59','2007-12-30');
    -> 1

iOS Detection of Screenshot?

I found the answer!! Taking a screenshot interrupts any touches that are on the screen. This is why snapchat requires holding to see the picture. Reference: http://tumblr.jeremyjohnstone.com/post/38503925370/how-to-detect-screenshots-on-ios-like-snapchat

Top 5 time-consuming SQL queries in Oracle

It depends which version of oracle you have, for 9i and below Statspack is what you are after, 10g and above, you want awr , both these tools will give you the top sql's and lots of other stuff.

JQuery to load Javascript file dynamically

I realize I am a little late here, (5 years or so), but I think there is a better answer than the accepted one as follows:

$("#addComment").click(function() {
    if(typeof TinyMCE === "undefined") {
        $.ajax({
            url: "tinymce.js",
            dataType: "script",
            cache: true,
            success: function() {
                TinyMCE.init();
            }
        });
    }
});

The getScript() function actually prevents browser caching. If you run a trace you will see the script is loaded with a URL that includes a timestamp parameter:

http://www.yoursite.com/js/tinymce.js?_=1399055841840

If a user clicks the #addComment link multiple times, tinymce.js will be re-loaded from a differently timestampped URL. This defeats the purpose of browser caching.

===

Alternatively, in the getScript() documentation there is a some sample code that demonstrates how to enable caching by creating a custom cachedScript() function as follows:

jQuery.cachedScript = function( url, options ) {

    // Allow user to set any option except for dataType, cache, and url
    options = $.extend( options || {}, {
        dataType: "script",
        cache: true,
        url: url
    });

    // Use $.ajax() since it is more flexible than $.getScript
    // Return the jqXHR object so we can chain callbacks
    return jQuery.ajax( options );
};

// Usage
$.cachedScript( "ajax/test.js" ).done(function( script, textStatus ) {
    console.log( textStatus );
});

===

Or, if you want to disable caching globally, you can do so using ajaxSetup() as follows:

$.ajaxSetup({
    cache: true
});

Find where python is installed (if it isn't default dir)

On windows running where python should work.

Trigger css hover with JS

I don't think what your asking is possible.

See: Hover Item with JQuery

Basically, adding a class is the only way to accomplish this that I am aware of.

PHP random string generator

The one line solution will be

str_shuffle(base64_encode(date('mdyhis').date('mdyhis')));

An existing connection was forcibly closed by the remote host

Simple solution for this common annoying issue:

Just go to your ".context.cs" file (located under ".context.tt" which located under your "*.edmx" file).

Then, add this line to your constructor:

public DBEntities() 
        : base("name=DBEntities") 
    { 
        this.Configuration.ProxyCreationEnabled = false; // ADD THIS LINE !
    }

hope this is helpful.

Trigger an action after selection select2

There was made some changes to the select2 events names (I think on v. 4 and later) so the '-' is changed into this ':'.
See the next examples:

$('#select').on("select2:select", function(e) { 
    //Do stuff
});

You can check all the events at the 'select2' plugin site: select2 Events

pthread_join() and pthread_exit()

In pthread_exit, ret is an input parameter. You are simply passing the address of a variable to the function.

In pthread_join, ret is an output parameter. You get back a value from the function. Such value can, for example, be set to NULL.

Long explanation:

In pthread_join, you get back the address passed to pthread_exit by the finished thread. If you pass just a plain pointer, it is passed by value so you can't change where it is pointing to. To be able to change the value of the pointer passed to pthread_join, it must be passed as a pointer itself, that is, a pointer to a pointer.

How to solve "The specified service has been marked for deletion" error

Sometimes this could happen during service deletion via PowerShell remote session script, especially when you are trying to delete service several times. In this case, try to recreate a session before the deletion:

Remove-PSSession -Session $session
$newSession = New-PSSession -ComputerName $Name  -Credential $creds -ErrorAction Stop
Enter-PSSession $newSession

How to automate drag & drop functionality using Selenium WebDriver Java

Drag and drop can be implemented like this...

public ObjectPage filter(int lowerThreshold, int highThreshold) {
    Actions action = new Actions(getWebDriver());
    action.dragAndDropBy(findElement(".className .thumbMin"), lowerThreshold, 0).perform();
    waitFor(elementIsNotDisplayed("#waiting_dialog"));

    action.dragAndDropBy(findElement(".className .thumbMax"), highThreshold, 0).perform();
    waitFor(elementIsNotDisplayed("#waiting_dialog"));
    return this;
}

Hope that helps!

Rails 4 - Strong Parameters - Nested Objects

I found this suggestion useful in my case:

  def product_params
    params.require(:product).permit(:name).tap do |whitelisted|
      whitelisted[:data] = params[:product][:data]
    end
  end

Check this link of Xavier's comment on github.

This approach whitelists the entire params[:measurement][:groundtruth] object.

Using the original questions attributes:

  def product_params
    params.require(:measurement).permit(:name, :groundtruth).tap do |whitelisted|
      whitelisted[:groundtruth] = params[:measurement][:groundtruth]
    end
  end

Counting the occurrences / frequency of array elements

Don't use two arrays for the result, use an object:

a      = [5, 5, 5, 2, 2, 2, 2, 2, 9, 4];
result = { };
for(var i = 0; i < a.length; ++i) {
    if(!result[a[i]])
        result[a[i]] = 0;
    ++result[a[i]];
}

Then result will look like:

{
    2: 5,
    4: 1,
    5: 3,
    9: 1
}

Giving my function access to outside variable

By default, when you are inside a function, you do not have access to the outer variables.


If you want your function to have access to an outer variable, you have to declare it as global, inside the function :

function someFuntion(){
    global $myArr;
    $myVal = //some processing here to determine value of $myVal
    $myArr[] = $myVal;
}

For more informations, see Variable scope.

But note that using global variables is not a good practice : with this, your function is not independant anymore.


A better idea would be to make your function return the result :

function someFuntion(){
    $myArr = array();       // At first, you have an empty array
    $myVal = //some processing here to determine value of $myVal
    $myArr[] = $myVal;      // Put that $myVal into the array
    return $myArr;
}

And call the function like this :

$result = someFunction();


Your function could also take parameters, and even work on a parameter passed by reference :

function someFuntion(array & $myArr){
    $myVal = //some processing here to determine value of $myVal
    $myArr[] = $myVal;      // Put that $myVal into the array
}

Then, call the function like this :

$myArr = array( ... );
someFunction($myArr);  // The function will receive $myArr, and modify it

With this :

  • Your function received the external array as a parameter
  • And can modify it, as it's passed by reference.
  • And it's better practice than using a global variable : your function is a unit, independant of any external code.


For more informations about that, you should read the Functions section of the PHP manual, and,, especially, the following sub-sections :

jQuery ajax error function

Try this:

error: function(jqXHR, textStatus, errorThrown) {
  console.log(textStatus, errorThrown);
}

If you want to inform your frontend about a validation error, try to return json:

dataType: 'json',
success: function(data, textStatus, jqXHR) {
   console.log(data.error);
}

Your asp script schould return:

{"error": true}

Redirect from asp.net web api post action

    [HttpGet]
    public RedirectResult Get()
    {
        return RedirectPermanent("https://www.google.com");
    }

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

You may want to know why this is happening. Together with the great explanation by that other guy, find a reference of Why does my shell script choke on whitespace or other special characters? written by Gilles in Unix & Linux:

Why do I need to write "$foo"? What happens without the quotes?

$foo does not mean “take the value of the variable foo”. It means something much more complex:

  • First, take the value of the variable.
  • Field splitting: treat that value as a whitespace-separated list of fields, and build the resulting list. For example, if the variable contains foo * bar ? then the result of this step is the 3-element list foo, *, bar.
  • Filename generation: treat each field as a glob, i.e. as a wildcard pattern, and replace it by the list of file names that match this pattern. If the pattern doesn't match any files, it is left unmodified. In our example, this results in the list containing foo, following by the list of files in the current directory, and finally bar. If the current directory is empty, the result is foo, *, bar.

Note that the result is a list of strings. There are two contexts in shell syntax: list context and string context. Field splitting and filename generation only happen in list context, but that's most of the time. Double quotes delimit a string context: the whole double-quoted string is a single string, not to be split. (Exception: "$@" to expand to the list of positional parameters, e.g. "$@" is equivalent to "$1" "$2" "$3" if there are three positional parameters. See What is the difference between $* and $@?)

The same happens to command substitution with $(foo) or with `foo`. On a side note, don't use `foo`: its quoting rules are weird and non-portable, and all modern shells support $(foo) which is absolutely equivalent except for having intuitive quoting rules.

The output of arithmetic substitution also undergoes the same expansions, but that isn't normally a concern as it only contains non-expandable characters (assuming IFS doesn't contain digits or -).

See When is double-quoting necessary? for more details about the cases when you can leave out the quotes.

Unless you mean for all this rigmarole to happen, just remember to always use double quotes around variable and command substitutions. Do take care: leaving out the quotes can lead not just to errors but to security holes.

How do I select text nodes with jQuery?

Jauco posted a good solution in a comment, so I'm copying it here:

$(elem)
  .contents()
  .filter(function() {
    return this.nodeType === 3; //Node.TEXT_NODE
  });

When should I use a struct rather than a class in C#?

Whenever you:

  1. don't need polymorphism,
  2. want value semantics, and
  3. want to avoid heap allocation and the associated garbage collection overhead.

The caveat, however, is that structs (arbitrarily large) are more expensive to pass around than class references (usually one machine word), so classes could end up being faster in practice.

Upload files with HTTPWebrequest (multipart/form-data)

I was looking for something like this, Found in : http://bytes.com/groups/net-c/268661-how-upload-file-via-c-code (modified for correctness):

public static string UploadFilesToRemoteUrl(string url, string[] files, NameValueCollection formFields = null)
{
    string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x");

    HttpWebRequest request = (HttpWebRequest) WebRequest.Create(url);
    request.ContentType = "multipart/form-data; boundary=" +
                            boundary;
    request.Method = "POST";
    request.KeepAlive = true;

    Stream memStream = new System.IO.MemoryStream();

    var boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" +
                                                            boundary + "\r\n");
    var endBoundaryBytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" +
                                                                boundary + "--");


    string formdataTemplate = "\r\n--" + boundary +
                                "\r\nContent-Disposition: form-data; name=\"{0}\";\r\n\r\n{1}";

    if (formFields != null)
    {
        foreach (string key in formFields.Keys)
        {
            string formitem = string.Format(formdataTemplate, key, formFields[key]);
            byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
            memStream.Write(formitembytes, 0, formitembytes.Length);
        }
    }

    string headerTemplate =
        "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\n" +
        "Content-Type: application/octet-stream\r\n\r\n";

    for (int i = 0; i < files.Length; i++)
    {
        memStream.Write(boundarybytes, 0, boundarybytes.Length);
        var header = string.Format(headerTemplate, "uplTheFile", files[i]);
        var headerbytes = System.Text.Encoding.UTF8.GetBytes(header);

        memStream.Write(headerbytes, 0, headerbytes.Length);

        using (var fileStream = new FileStream(files[i], FileMode.Open, FileAccess.Read))
        {
            var buffer = new byte[1024];
            var bytesRead = 0;
            while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
            {
                memStream.Write(buffer, 0, bytesRead);
            }
        }
    }

    memStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);
    request.ContentLength = memStream.Length;

    using (Stream requestStream = request.GetRequestStream())
    {
        memStream.Position = 0;
        byte[] tempBuffer = new byte[memStream.Length];
        memStream.Read(tempBuffer, 0, tempBuffer.Length);
        memStream.Close();
        requestStream.Write(tempBuffer, 0, tempBuffer.Length);
    }

    using (var response = request.GetResponse())
    {
        Stream stream2 = response.GetResponseStream();
        StreamReader reader2 = new StreamReader(stream2);
        return reader2.ReadToEnd();
    }
}

add new element in laravel collection object

It looks like you have everything correct according to Laravel docs, but you have a typo

$item->push($product);

Should be

$items->push($product);

I also want to think the actual method you're looking for is put

$items->put('products', $product);

How do I implement a callback in PHP?

create_function did not work for me inside a class. I had to use call_user_func.

<?php

class Dispatcher {
    //Added explicit callback declaration.
    var $callback;

    public function Dispatcher( $callback ){
         $this->callback = $callback;
    }

    public function asynchronous_method(){
       //do asynch stuff, like fwrite...then, fire callback.
       if ( isset( $this->callback ) ) {
            if (function_exists( $this->callback )) call_user_func( $this->callback, "File done!" );
        }
    }

}

Then, to use:

<?php 
include_once('Dispatcher.php');
$d = new Dispatcher( 'do_callback' );
$d->asynchronous_method();

function do_callback( $data ){
   print 'Data is: ' .  $data .  "\n";
}
?>

[Edit] Added a missing parenthesis. Also, added the callback declaration, I prefer it that way.

Get css top value as number not as string?

A jQuery plugin based on M4N's answer

jQuery.fn.cssNumber = function(prop){
    var v = parseInt(this.css(prop),10);
    return isNaN(v) ? 0 : v;
};

So then you just use this method to get number values

$("#logo").cssNumber("top")