Programs & Examples On #Diskspace

Issues relating to availability of disk space.

How do I monitor the computer's CPU, memory, and disk usage in Java?

In JDK 1.7, you can get system CPU and memory usage via This is different than

long    getCommittedVirtualMemorySize()
Returns the amount of virtual memory that is guaranteed to be available to the running process in bytes, or -1 if this operation is not supported.

long    getFreePhysicalMemorySize()
Returns the amount of free physical memory in bytes.

long    getFreeSwapSpaceSize()
Returns the amount of free swap space in bytes.

double  getProcessCpuLoad()
Returns the "recent cpu usage" for the Java Virtual Machine process.

long    getProcessCpuTime()
Returns the CPU time used by the process on which the Java virtual machine is running in nanoseconds.

double  getSystemCpuLoad()
Returns the "recent cpu usage" for the whole system.

long    getTotalPhysicalMemorySize()
Returns the total amount of physical memory in bytes.

long    getTotalSwapSpaceSize()
Returns the total amount of swap space in bytes.

Android SDK folder taking a lot of disk space. Do we need to keep all of the System Images?

You do not need to keep the system images unless you want to use the emulator on your desktop. Along with it you can remove other unwanted stuff to clear disk space.

Adding as an answer to my own question as I've had to narrate this to people in my team more than a few times. Hence this answer as a reference to share with other curious ones.

In the last few weeks there were several colleagues who asked me how to safely get rid of the unwanted stuff to release disk space (most of them were beginners). I redirected them to this question but they came back to me for steps. So for android beginners here is a step by step guide to safely remove unwanted stuff.


  • Do not blindly delete everything directly from disk that you "think" is not required occupying. I did that once and had to re-download.
  • Make sure you have a list of all active projects with the kind of emulators (if any) and API Levels and Build tools required for those to continue working/compiling properly.

First, be sure you are not going to use emulators and will always do you development on a physical device. In case you are going to need emulators, note down the API Levels and type of emulators you'll need. Do not remove those. For the rest follow the below steps:

Steps to safely clear up unwanted stuff from Android SDK folder on the disk

  1. Open the Stand Alone Android SDK Manager. To open do one of the following:
  • Click the SDK Manager button on toolbar in android studio or eclipse
  • In Android Studio, go to settings and search "Android SDK". Click Android SDK -> "Open Standalone SDK Manager"
  • In Eclipse, open the "Window" menu and select "Android SDK Manager"
  • Navigate to the location of the android-sdk directory on your computer and run "SDK Manager.exe"


  1. Uncheck all items ending with "System Image". Each API Level will have more than a few. In case you need some and have figured the list already leave them checked to avoid losing them and having to re-download.


  1. Optional (may help save a marginally more amount of disk space): To free up some more space, you can also entirely uncheck unrequired API levels. Be careful again to avoid re-downloading something you are actually using in other projects.


  1. In the end make sure you have at least the following (check image below) for the remaining API levels to be able to seamlessly work with your physical device.

In the end the clean android sdk installed components should look something like this in the SDK manager.

enter image description here

Get free disk space

As this answer and @RichardOD suggested , you should do like this:

[DllImport("kernel32.dll", SetLastError=true, CharSet=CharSet.Auto)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool GetDiskFreeSpaceEx(string lpDirectoryName,
   out ulong lpFreeBytesAvailable,
   out ulong lpTotalNumberOfBytes,
   out ulong lpTotalNumberOfFreeBytes);

ulong FreeBytesAvailable;
ulong TotalNumberOfBytes;
ulong TotalNumberOfFreeBytes;

bool success = GetDiskFreeSpaceEx(@"\\mycomputer\myfolder",
                                  out FreeBytesAvailable,
                                  out TotalNumberOfBytes,
                                  out TotalNumberOfFreeBytes);
    throw new System.ComponentModel.Win32Exception();

Console.WriteLine("Free Bytes Available:      {0,15:D}", FreeBytesAvailable);
Console.WriteLine("Total Number Of Bytes:     {0,15:D}", TotalNumberOfBytes);
Console.WriteLine("Total Number Of FreeBytes: {0,15:D}", TotalNumberOfFreeBytes);

MacOS Xcode CoreSimulator folder very big. Is it ok to delete content?

Try to run xcrun simctl delete unavailable in your terminal.

Original answer: Xcode - free to clear devices folder?

Find size and free space of the filesystem containing a given file

As of Python 3.3, there an easy and direct way to do this with the standard library:

$ cat 
#!/usr/bin/env python3

import shutil

total, used, free = shutil.disk_usage(__file__)
print(total, used, free)

$ ./ 
1007870246912 460794834944 495854989312

These numbers are in bytes. See the documentation for more info.

How to access JSON Object name/value?

In stead of parsing JSON you can do like followng:

  dataType: 'json' // using json, jquery will make parse for  you

To access a property of your JSON do following:



Why you need data[0] because data is an array, so to its content retrieve you need data[0] (first element), which gives you an object {"name":"myName" ,"address": "myAddress" }.

And to access property of an object rule is:

or sometimes

Object["property"] // in some case

So you need

data[0].name and so on to get what you want.

If you not

set dataType: json then you need to parse them using $.parseJSON() and to retrieve data like above.

Angular2 If ngModel is used within a form tag, either the name attribute must be set or the form

As every developer have a common habit, not to read the complete error, just read the first line and start looking for answer from someone else :):) I am also one of them, that's why I am here:

Read the error, clearly saying:

Example 1: <input [(ngModel)]="person.firstName" name="first">
Example 2: <input [(ngModel)]="person.firstName" [ngModelOptions]="{standalone: true}">

What more we need to understand this error?

Use any one option everything will work smooth.

find -mtime files older than 1 hour

What about -mmin?

find /var/www/html/audio -daystart -maxdepth 1 -mmin +59 -type f -name "*.mp3" \
    -exec rm -f {} \;

From man find:

-mmin n
        File's data was last modified n minutes ago.

Also, make sure to test this first!

... -exec echo rm -f '{}' \;
          ^^^^ Add the 'echo' so you just see the commands that are going to get
               run instead of actual trying them first.

How to Call a JS function using OnClick event

I removed your document.getElementById("Save").onclick = before your functions, because it's an event already being called on your button. I also had to call the two functions separately by the onclick event.

     <!DOCTYPE html>
       function fun()
         //validation code to see State field is mandatory.  
        function f1()
          alert("f1 called");
           //form validation that recalls the page showing with supplied inputs.    
      <form name="form1" id="form1" method="post">
                <select id="state ID">
                   <option value="ap">ap</option>
                   <option value="bp">bp</option>

       <table><tr><td id="Save" onclick="f1(); fun();">click</td></tr></table>


How to parse XML and count instances of a particular node attribute?

There are many options out there. cElementTree looks excellent if speed and memory usage are an issue. It has very little overhead compared to simply reading in the file using readlines.

The relevant metrics can be found in the table below, copied from the cElementTree website:

library                         time    space
xml.dom.minidom (Python 2.1)    6.3 s   80000K
gnosis.objectify                2.0 s   22000k
xml.dom.minidom (Python 2.4)    1.4 s   53000k
ElementTree 1.2                 1.6 s   14500k  
ElementTree 1.2.4/1.3           1.1 s   14500k  
cDomlette (C extension)         0.540 s 20500k
PyRXPU (C extension)            0.175 s 10850k
libxml2 (C extension)           0.098 s 16000k
readlines (read as utf-8)       0.093 s 8850k
cElementTree (C extension)  --> 0.047 s 4900K <--
readlines (read as ascii)       0.032 s 5050k   

As pointed out by @jfs, cElementTree comes bundled with Python:

  • Python 2: from xml.etree import cElementTree as ElementTree.
  • Python 3: from xml.etree import ElementTree (the accelerated C version is used automatically).

Delete all local git branches

The following script deletes branches. Use it and modify it at your own risk, etc. etc.

Based on the other answers in this question, I ended up writing a quick bash script for myself. I called it "gitbd" (git branch -D) but if you use it, you can rename it to whatever you want.

gitbd() {
if [ $# -le 1 ]
    local branches_to_delete=`git for-each-ref --format '%(refname:short)' refs/heads/ | grep "$1"`
    printf "Matching branches:\n\n$branches_to_delete\n\nDelete? [Y/n] "
    read -n 1 -r # Immediately continue after getting 1 keypress
    echo # Move to a new line
    if [[ ! $REPLY == 'N' && ! $REPLY == 'n' ]]
        echo $branches_to_delete | xargs git branch -D
  echo "This command takes one arg (match pattern) or no args (match all)"

It will offer to delete any branches which match a pattern argument, if passed in, or all local branches when called with with no arguments. It will also give you a confirmation step, since, you know, we're deleting things, so that's nice.

It's kind of dumb - if there are no branches that match the pattern, it doesn't realize it.

An example output run:

$ gitbd test
Matching branches:


Delete? [Y/n] 

pull/push from multiple remote locations

Adding the all remote gets a bit tedious as you have to setup on each machine that you use.

Also, the bash and git aliases provided all assume that you have will push to all remotes. (Ex: I have a fork of sshag that I maintain on GitHub and GitLab. I have the upstream remote added, but I don't have permission to push to it.)

Here is a git alias that only pushes to remotes with a push URL that includes @.

psall    = "!f() { \
    for R in $(git remote -v | awk '/@.*push/ { print $1 }'); do \
    git push $R $1; \
    done \
    }; f"

Send email using the GMail SMTP server from a PHP page

To install PEAR's Mail.php in Ubuntu, run following set of commands:

    sudo apt-get install php-pear
    sudo pear install mail
    sudo pear install Net_SMTP
    sudo pear install Auth_SASL
    sudo pear install mail_mime

How to insert strings containing slashes with sed?

Great answer from Anonymous. \ solved my problem when I tried to escape quotes in HTML strings.

So if you use sed to return some HTML templates (on a server), use double backslash instead of single:

var htmlTemplate = "<div style=\\"color:green;\\"></div>";

Turning multi-line string into single comma-separated

Don't seen this simple solution with awk

awk 'b{b=b","}{b=b$2}END{print b}' infile

How do I calculate the MD5 checksum of a file in Python?

In Python 3.8+ you can do

import hashlib

with open("your_filename.png", "rb") as f:
    file_hash = hashlib.md5()
    while chunk :=

print(file_hash.hexdigest())  # to get a printable str instead of bytes

On Python 3.7 and below:

with open("your_filename.png", "rb") as f:
    file_hash = hashlib.md5()
    chunk =
    while chunk:
        chunk =


This reads the file 8192 (or 2¹³) bytes at a time instead of all at once with to use less memory.

Consider using hashlib.blake2b instead of md5 (just replace md5 with blake2b in the above snippets). It's cryptographically secure and faster than MD5.

How to block until an event is fired in c#

If you're happy to use the Microsoft Reactive Extensions, then this can work nicely:

public class Foo
    public delegate void MyEventHandler(object source, MessageEventArgs args);
    public event MyEventHandler _event;
    public string ReadLine()
        return Observable
            .FromEventPattern<MyEventHandler, MessageEventArgs>(
                h => this._event += h,
                h => this._event -= h)
            .Select(ep => ep.EventArgs.Message)
    public void SendLine(string message)
        _event(this, new MessageEventArgs() { Message = message });

public class MessageEventArgs : EventArgs
    public string Message;

I can use it like this:

var foo = new Foo();

        () => foo.SendLine("Bar!"));

var resp = foo.ReadLine();


I needed to call the SendLine message on a different thread to avoid locking, but this code shows that it works as expected.

How to strip a specific word from a string?

Providing you know the index value of the beginning and end of each word you wish to replace in the character array, and you only wish to replace that particular chunk of data, you could do it like this.

>>> s = "papa is papa is papa"
>>> s = s[:8]+s[8:13].replace("papa", "mama")+s[13:]
>>> print(s)
papa is mama is papa

Alternatively, if you also wish to retain the original data structure, you could store it in a dictionary.

>>> bin = {}
>>> s = "papa is papa is papa"
>>> bin["0"] = s
>>> s = s[:8]+s[8:13].replace("papa", "mama")+s[13:]
>>> print(bin["0"])
papa is papa is papa
>>> print(s)
papa is mama is papa

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

$date = new \DateTime("now", new \DateTimeZone('Asia/Calcutta') );
         $day = $date->format('D');
         $weekendnaame = weekedName();
         $weekid =$weekendnaame[$day];
          $dayname = 0;
        $weekiarray = weekendArray($weekid);
        foreach ($weekiarray as $key => $value) {
            if (in_array($value, $request->get('week_id')))
            $dayname = $key+1;


function weeked(){
  $week = array("1"=>"Sunday", "2"=>"Monday", "3"=>"Tuesday", "4"=>"Wednesday", "5"=>"Thursday", "6"=>"Friday", "7"=>"Saturday");
  return $week;
function weekendArray($day){
        $favcolor = $day;

switch ($favcolor) {
  case 1:
    $array = array(2,3,4,5,6,7,1);
  case 2:
    $array = array(3,4,5,6,7,1,2);
  case 3:
    $array = array(4,5,6,7,1,2,3);
    case 4:
    $array = array(5,6,7,1,2,3,4);
    case 5:
    $array = array(6,7,1,2,3,4,5);
    case 6:
    $array = array(7,1,2,3,4,5,6);
     case 7:
    $array = array(1,2,3,4,5,6,7);
    $array = array(1,2,3,4,5,6,7);
return  $array;
function weekedName(){
  $week = array("Sun"=>0,"Mun"=>1,"Tue"=>3,"Wed"=>4,"Thu"=>5,"Fri"=>6,"Sat"=>7);
  return $week;

How to lazy load images in ListView in Android

I think this issue is very popular among Android developers, and there are plenty of such libraries that claims to resolve this issue, but only a few of them seems to be on the mark. AQuery is one such library, but it is better than most of them in all aspects and is worth trying for.

Python Error: unsupported operand type(s) for +: 'int' and 'NoneType'

When none of the if test in number_translator() evaluate to true, the function returns None. The error message is the consequence of that.

Whenever you see an error that include 'NoneType' that means that you have an operand or an object that is None when you were expecting something else.

A formula to copy the values from a formula to another column

you can use those functions together with iferror as a work around.


How to Detect cause of 503 Service Temporarily Unavailable error and handle it?

There is of course some apache log files. Search in your apache configuration files for 'Log' keyword, you'll certainly find plenty of them. Depending on your OS and installation places may vary (in a Typical Linux server it would be /var/log/apache2/[access|error].log).

Having a 503 error in Apache usually means the proxied page/service is not available. I assume you're using tomcat and that means tomcat is either not responding to apache (timeout?) or not even available (down? crashed?). So chances are that it's a configuration error in the way to connect apache and tomcat or an application inside tomcat that is not even sending a response for apache.

Sometimes, in production servers, it can as well be that you get too much traffic for the tomcat server, apache handle more request than the proxyied service (tomcat) can accept so the backend became unavailable.

async at console app in C#?

In most project types, your async "up" and "down" will end at an async void event handler or returning a Task to your framework.

However, Console apps do not support this.

You can either just do a Wait on the returned task:

static void Main()
  // or, if you want to avoid exceptions being wrapped into AggregateException:
  //  MainAsync().GetAwaiter().GetResult();

static async Task MainAsync()

or you can use your own context like the one I wrote:

static void Main()
  AsyncContext.Run(() => MainAsync());

static async Task MainAsync()

More information for async Console apps is on my blog.

operator << must take exactly one argument

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

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

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

    int value = 8;

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

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

MyObj mo;

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

// which decomposes to...

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

MyObj mo;

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

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

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

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

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

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

    int value = 8;

This syntax will irritate many coders now....

MyObj mo;

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

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

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

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

SQL: How to to SUM two values from different tables

select region,sum(number) total
    select region,number
    from cash_table
    union all
    select region,number
    from cheque_table
) t
group by region

MySQL check if a table exists without throwing an exception

Why you make it so hard to understand?

function table_exist($table){ 
    $pTableExist = mysql_query("show tables like '".$table."'");
    if ($rTableExist = mysql_fetch_array($pTableExist)) {
        return "Yes";
        return "No";

How to print an exception in Python 3?

I'm guessing that you need to assign the Exception to a variable. As shown in the Python 3 tutorial:

def fails():
    x = 1 / 0

except Exception as ex:

To give a brief explanation, as is a pseudo-assignment keyword used in certain compound statements to assign or alias the preceding statement to a variable.

In this case, as assigns the caught exception to a variable allowing for information about the exception to stored and used later, instead of needing to be dealt with immediately. (This is discussed in detail in the Python 3 Language Reference: The try Statement.)

The other compound statement using as is the with statement:

def opening(filename):
    f = open(filename)
        yield f

with opening(filename) as f:
    # data from f...

Here, with statements are used to wrap the execution of a block with methods defined by context managers. This functions like an extended try...except...finally statement in a neat generator package, and the as statement assigns the generator-produced result from the context manager to a variable for extended use. (This is discussed in detail in the Python 3 Language Reference: The with Statement.)

Finally, as can be used when importing modules, to alias a module to a different (usually shorter) name:

import as fbb

This is discussed in detail in the Python 3 Language Reference: The import Statement.

Call fragment from fragment

In MainActivity

private static fragmentManager;

protected void onCreate(Bundle savedInstanceState) {

    fragmentManager = getSupportFragmentManager();                                                                 


public void secondFragment() {

            .setCustomAnimations(R.anim.right_enter, R.anim.left_out)
            .replace(, new secondFragment(), "secondFragmentTag").addToBackStack(null)

In FirstFragment call SecondFrgment Like this:

new MainActivity().secondFragment();

Is it possible to decompile an Android .apk file?

Decompilation of APK file is possible. But it might be difficult to understand the code if it is obfuscated.

ApkTool to view resources inside APK File

  • Extracts AndroidManifest.xml and everything in res folder(layout xml files, images, htmls used on webview etc..)
  • command : apktool.bat d sampleApp.apk
  • NOTE: You can achieve this by using zip utility like 7-zip. But, It also extracts the .smali file of all .class files.

Using dex2jar

  • Generates .jar file from .apk file, we need JD-GUI to view the source code from this .jar.
  • command : dex2jar sampleApp.apk

Decompiling .jar using JD-GUI

  • decompiles the .class files (obfuscated- in a case of the android app, but a readable original code is obtained in a case of other .jar file). i.e., we get .java back from the application.

IO Error: The Network Adapter could not establish the connection


  1. The database isn't running
  2. You got the URL wrong
  3. There is a firewall in the way.

(This strange error message is produced by Oracle's JDBC driver when it can't connect to the database server. 'Network adapter' appears to refer to some component of their code, which isn't very useful. Real network adapters (NICs) don't establish connections at all: TCP protocol stacks do that. It would have been a lot more useful if they had just let the original ConnectException be thrown, or at least used its error message and let it appear in the stack trace.)

String formatting in Python 3

Here are the docs about the "new" format syntax. An example would be:

"({:d} goals, ${:d})".format(self.goals, self.penalties)

If both goals and penalties are integers (i.e. their default format is ok), it could be shortened to:

"({} goals, ${})".format(self.goals, self.penalties)

And since the parameters are fields of self, there's also a way of doing it using a single argument twice (as @Burhan Khalid noted in the comments):

"({0.goals} goals, ${0.penalties})".format(self)


  • {} means just the next positional argument, with default format;
  • {0} means the argument with index 0, with default format;
  • {:d} is the next positional argument, with decimal integer format;
  • {0:d} is the argument with index 0, with decimal integer format.

There are many others things you can do when selecting an argument (using named arguments instead of positional ones, accessing fields, etc) and many format options as well (padding the number, using thousands separators, showing sign or not, etc). Some other examples:

"({goals} goals, ${penalties})".format(goals=2, penalties=4)
"({goals} goals, ${penalties})".format(**self.__dict__)

"first goal: {0.goal_list[0]}".format(self)
"second goal: {.goal_list[1]}".format(self)

"conversion rate: {:.2f}".format(self.goals / self.shots) # '0.20'
"conversion rate: {:.2%}".format(self.goals / self.shots) # '20.45%'
"conversion rate: {:.0%}".format(self.goals / self.shots) # '20%'

"self: {!s}".format(self) # 'Player: Bob'
"self: {!r}".format(self) # '<__main__.Player instance at 0x00BF7260>'

"games: {:>3}".format(  # 'games: 123'
"games: {:>3}".format(  # 'games:   4'
"games: {:0>3}".format( # 'games: 004'

Note: As others pointed out, the new format does not supersede the former, both are available both in Python 3 and the newer versions of Python 2 as well. Some may say it's a matter of preference, but IMHO the newer is much more expressive than the older, and should be used whenever writing new code (unless it's targeting older environments, of course).

java.lang.OutOfMemoryError: Java heap space in Maven

To temporarily work around this problem, I found the following to be the quickest way:

export JAVA_TOOL_OPTIONS="-Xmx1024m -Xms1024m"

Where are the recorded macros stored in Notepad++?

You can find the shortcuts.xml in AppData\Roaming\Notepad++\ path only when using the default settings. If you have backup configured, you can find and set the path in Preferences -> Backup -> Backup path.

When these settings are applied, files in AppData directory won't be used.

Using jquery to delete all elements with a given id

.remove() should remove all of them. I think the problem is that you're using an ID. There's only supposed to be one HTML element with a particular ID on the page, so jQuery is optimizing and not searching for them all. Use a class instead.

How can I create an utility class?

For a completely stateless utility class in Java, I suggest the class be declared public and final, and have a private constructor to prevent instantiation. The final keyword prevents sub-classing and can improve efficiency at runtime.

The class should contain all static methods and should not be declared abstract (as that would imply the class is not concrete and has to be implemented in some way).

The class should be given a name that corresponds to its set of provided utilities (or "Util" if the class is to provide a wide range of uncategorized utilities).

The class should not contain a nested class unless the nested class is to be a utility class as well (though this practice is potentially complex and hurts readability).

Methods in the class should have appropriate names.

Methods only used by the class itself should be private.

The class should not have any non-final/non-static class fields.

The class can also be statically imported by other classes to improve code readability (this depends on the complexity of the project however).


public final class ExampleUtilities {
    // Example Utility method
    public static int foo(int i, int j) {
        int val;

        //Do stuff

        return val;

    // Example Utility method overloaded
    public static float foo(float i, float j) {
        float val;

        //Do stuff

        return val;

    // Example Utility method calling private method
    public static long bar(int p) {
        return hid(p) * hid(p);

    // Example private method
    private static long hid(int i) {
        return i * 2 + 1;

Perhaps most importantly of all, the documentation for each method should be precise and descriptive. Chances are methods from this class will be used very often and its good to have high quality documentation to complement the code.

How to get the category title in a post in Wordpress?

Use get_the_category() like this:

foreach((get_the_category()) as $category) { 
    echo $category->cat_name . ' '; 

It returns a list because a post can have more than one category.

The documentation also explains how to do this from outside the loop.

Inline onclick JavaScript variable

Yes, JavaScript variables will exist in the scope they are created.

var bannerID = 55;

<input id="EditBanner" type="button" 
  value="Edit Image" onclick="EditBanner(bannerID);"/>

function EditBanner(id) {
   //Do something with id

If you use event handlers and jQuery it is simple also

$("#EditBanner").click(function() {

How can I return the current action in an ASP.NET MVC view?

In MVC you should provide the View with all data, not let the View collect its own data so what you can do is to set the CSS class in your controller action.

ViewData["CssClass"] = "bold";

and pick out this value from your ViewData in your View

Node.js Mongoose.js string to ObjectId function

You can do it like so:

var mongoose = require('mongoose');
var id = mongoose.Types.ObjectId('4edd40c86762e0fb12000003');

TypeError: a bytes-like object is required, not 'str'

A bit of encoding can solve this:

Client Side:

message = input("->")
clientSocket.sendto(message.encode('utf-8'), (address, port))

Server Side:

data = s.recv(1024)
modifiedMessage, serverAddress = clientSocket.recvfrom(message.decode('utf-8'))

Getting an element from a Set


It seems that Set plays a useful role in providing a means of comparison. It is designed not to store duplicate elements.

Because of this intention/design, if one were to get() a reference to the stored object, then mutate it, it is possible that the design intentions of Set could be thwarted and could cause unexpected behavior.

From the JavaDocs

Great care must be exercised if mutable objects are used as set elements. The behavior of a set is not specified if the value of an object is changed in a manner that affects equals comparisons while the object is an element in the set.


Now that Streams have been introduced one can do the following
.filter(object ->

Python/Django: log to console under runserver, log to file under Apache

Text printed to stderr will show up in httpd's error log when running under mod_wsgi. You can either use print directly, or use logging instead.

print >>sys.stderr, 'Goodbye, cruel world!'

Most simple code to populate JTable from ResultSet

The JTable constructor accepts two arguments 2dimension Object Array for the data, and String Array for the column names.


import java.awt.BorderLayout;
import java.awt.Color;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;

public class Test6 extends JFrame {

    public Test6(){     
        Mpanel m = new Mpanel();

    class Mpanel extends JPanel {       

        JTable mTable;
        private Object[][] cells = {{"Vivek",10.00},{"Vishal",20.00}};
        private String[] columnNames = { "Planet", "Radius" };
        JScrollPane mScroll;

        public Mpanel(){

        public void setComponent(){
            mTable = new JTable(cells,columnNames);
            mScroll = new JScrollPane(mTable);


    public static void main(String[] args){     
        new Test6().setVisible(true);

Change One Cell's Data in mysql

Try the following:

UPDATE TableName SET ValueName=@parameterName WHERE

Efficient way to insert a number into a sorted array of numbers?

TypeScript version with custom compare method:

const { compare } = new Intl.Collator(undefined, {
  numeric: true,
  sensitivity: "base"

const insert = (items: string[], item: string) => {
    let low = 0;
    let high = items.length;

    while (low < high) {
        const mid = (low + high) >> 1;
        compare(items[mid], item) > 0
            ? (high = mid)
            : (low = mid + 1);

    items.splice(low, 0, item);


const items = [];

insert(items, "item 12");
insert(items, "item 1");
insert(items, "item 2");
insert(items, "item 22");


// ["item 1", "item 2", "item 12", "item 22"]

How to check whether a string is a valid HTTP URL?

Try this to validate HTTP URLs (uriName is the URI you want to test):

Uri uriResult;
bool result = Uri.TryCreate(uriName, UriKind.Absolute, out uriResult) 
    && uriResult.Scheme == Uri.UriSchemeHttp;

Or, if you want to accept both HTTP and HTTPS URLs as valid (per J0e3gan's comment):

Uri uriResult;
bool result = Uri.TryCreate(uriName, UriKind.Absolute, out uriResult) 
    && (uriResult.Scheme == Uri.UriSchemeHttp || uriResult.Scheme == Uri.UriSchemeHttps);

start/play embedded (iframe) youtube-video on click of an image

Html Code:-

<a href="#" id="playerID">Play</a>
<iframe src="" class="embed-responsive-item" data-play="0" id="VdoID" ></iframe>

Jquery Code:-

    var videoURL = $('#VdoID').attr('src'),
    dataplay = $('#VdoID').attr('data-play');

    //for check autoplay
    //if not set autoplay=1
    if(dataplay == 0 ){
        var videoURL = $('#VdoID').attr('src');
        videoURL = videoURL.replace("?autoplay=1", "");



Thats It!

Rename a file in C#

Take a look at System.IO.File.Move, "move" the file to a new name.

System.IO.File.Move("oldfilename", "newfilename");

lvalue required as left operand of assignment

You cannot assign an rvalue to an rvalue.

if (strcmp("hello", "hello") = 0)

is wrong. Suggestions:

if (strcmp("hello", "hello") == 0)

= is the assign operator.
== is the equal to operator.
I know many new programmers are confused with this fact.

fetch in git doesn't get all branches

I had a similar problem, however in my case I could pull/push to the remote branch but git status didn't show the local branch state w.r.t the remote ones.

Also, in my case git config --get remote.origin.fetch didn't return anything

The problem is that there was a typo in the .git/config file in the fetch line of the respective remote block. Probably something I added by mistake previously (sometimes I directly look at this file, or even edit it)

So, check if your remote entry in the .git/config file is correct, e.g.:

[remote "origin"]
    url = https://[server]/[user or organization]/[repo].git
    fetch = +refs/heads/*:refs/remotes/origin/*

How to get numeric value from a prompt box?

Working Demo Reading more Info

parseInt(x) it will cast it into integer

x = parseInt(x);
x = parseInt(x,10); //the radix is 10 (decimal)

parseFloat(x) it will cast it into float

Working Demo Reading more Info

x = parseFloat(x);

you can directly use prompt

var x = parseInt(prompt("Enter a Number", "1"), 10)

Adding gif image in an ImageView in android

Firstly add a dependency in the module:app build.gradle file

compile 'pl.droidsonroids.gif:android-gif-drawable:1.1.+'

Then, in the layout file


How to get the path of current worksheet in VBA?

Use Application.ActiveWorkbook.Path for just the path itself (without the workbook name) or Application.ActiveWorkbook.FullName for the path with the workbook name.

Slick.js: Get current and total slides (ie. 3/5)

Based on the first proposition posted by @Mx. (posted sept.15th 2014) I created a variant to get a decent HTML markup for ARIA support.

    slide: 'img',
    autoplay: true,
    dots: true,
    dotsClass: 'custom_paging',
    customPaging: function (slider, i) {
        //FYI just have a look at the object to find available information
        //press f12 to access the console in most browsers
        //you could also debug or look in the source
        var slideNumber   = (i + 1),
            totalSlides = slider.slideCount;
        return '<a class="custom-dot" role="button" title="' + slideNumber + ' of ' + totalSlides + '"><span class="string">' + slideNumber + '</span></a>';

jsFiddle DEMO

Are there dictionaries in php?

Associative array in PHP actually considered as a dictionary.

An array in PHP is actually an ordered map. A map is a type that associates values to keys. it can be treated as an array, list (vector), hash table (an implementation of a map), dictionary, collection, stack, queue, and probably more.

$array = array(
    "foo" => "bar",
    "bar" => "foo",

// Using the short array syntax
$array = [
    "foo" => "bar",
    "bar" => "foo",

An array is different than a dictionary in that arrays have both an index and a key. Dictionaries only have keys and no index.

Execute jar file with multiple classpath libraries from command prompt

You can use maven-assembly-plugin, Here is the example from the official site:

                    <mainClass>your main class</mainClass>
                <id>make-assembly</id> <!-- this is used for inheritance merges -->
                <phase>package</phase> <!-- bind to the packaging phase -->

git clone through ssh

git clone git@server:Example/proyect.git

sqlplus: error while loading shared libraries: cannot open shared object file: No such file or directory

You can try usage:

# echo "/usr/lib/oracle/12.2/client64/lib" > /etc/
# ldconfig

This problem are because oracleinstant client not configure shared library.

Change SQLite database mode to read-write

On Ubuntu, change the owner to the Apache group and grant the right permissions (no, it's not 777):

sudo chgrp www-data <path to db.sqlite3>
sudo chmod 664 <path to db.sqlite3>


You can set the permissions for group and user as well.

sudo chown www-data:www-data <path to db.sqlite3>

How to include js and CSS in JSP with spring MVC

First you need to declare your resources in dispatcher-servlet file like this :

<mvc:resources mapping="/resources/**" location="/resources/folder/" />

Any request with url mapping /resources/** will directly look for /resources/folder/.

Now in jsp file you need to include your css file like this :

<link href="<c:url value="/resources/css/main.css" />" rel="stylesheet">

Similarly you can include js files.

Hope this solves your problem.

document.getElementById("remember").visibility = "hidden"; not working on a checkbox

This is the job for style property:

document.getElementById("remember").style.visibility = "visible";

System.currentTimeMillis() vs. new Date() vs. Calendar.getInstance().getTime()

System.currentTimeMillis() is obviously the most efficient since it does not even create an object, but new Date() is really just a thin wrapper about a long, so it is not far behind. Calendar, on the other hand, is relatively slow and very complex, since it has to deal with the considerably complexity and all the oddities that are inherent to dates and times (leap years, daylight savings, timezones, etc.).

It's generally a good idea to deal only with long timestamps or Date objects within your application, and only use Calendar when you actually need to perform date/time calculations, or to format dates for displaying them to the user. If you have to do a lot of this, using Joda Time is probably a good idea, for the cleaner interface and better performance.

Httpd returning 503 Service Unavailable with mod_proxy for Tomcat 8

Resolve issue Immediate, It's related to internal security

We, working for enterprise linux RedHat, found httpd server don't allow proxy to run, neither localhost or, nor any other external domain.

As investigate in server log found

[error] (13)Permission denied: proxy: AJP: attempt to connect to
   10.x.x.x:8069 ( failed

Audit log found similar port issue

type=AVC msg=audit(1265039669.305:14): avc:  denied  { name_connect } for  pid=4343 comm="httpd" dest=8069 
scontext=system_u:system_r:httpd_t:s0 tcontext=system_u:object_r:port_t:s0 tclass=tcp_socket

Due to internal default security of linux, this cause, now to fix (temporary)

 /usr/sbin/setsebool httpd_can_network_connect 1

Resolve Permanent Issue

/usr/sbin/setsebool -P httpd_can_network_connect 1

How do I toggle an element's class in pure JavaScript?

don't need regex just use classlist

var id=document.getElementById('myButton');

function toggle(el,classname){




<button id="myButton">Switch</button>

Simple Usage above Example

var id=document.getElementById('myButton');

function toggle(el,classname){




<button id="myButton">Switch</button>

Can you change what a symlink points to after it is created?

Just in case it helps: there is a way to edit a symlink with midnight commander (mc). The menu command is (in French on my mc interface):

Fichier / Éditer le lien symbolique

which may be translated to:

File / Edit symbolic link

The shortcut is C-x C-s

Maybe it internally uses the ln --force command, I don't know.

Now, I'm trying to find a way to edit a whole lot of symlinks at once (that's how I arrived here).

Giving multiple URL patterns to Servlet Filter

In case you are using the annotation method for filter definition (as opposed to defining them in the web.xml), you can do so by just putting an array of mappings in the @WebFilter annotation:

 * Filter implementation class LoginFilter
@WebFilter(urlPatterns = { "/faces/Html/Employee","/faces/Html/Admin", "/faces/Html/Supervisor"})
public class LoginFilter implements Filter {

And just as an FYI, this same thing works for servlets using the servlet annotation too:

 * Servlet implementation class LoginServlet
@WebServlet({"/faces/Html/Employee", "/faces/Html/Admin", "/faces/Html/Supervisor"})
public class LoginServlet extends HttpServlet {

How can I get useful error messages in PHP?

error_reporting(E_ALL | E_STRICT);
ini_set('display_errors', 1);
ini_set('html_errors', 1);

In addition, you can get more detailed information with xdebug.

Avoid web.config inheritance in child web application using inheritInChildApplications

We were getting an error related to this after a recent release of code to one of our development environments. We have an application that is a child of another application. This relationship has been working fine for YEARS until yesterday.

The problem:
We were getting a yellow stack trace error due to duplicate keys being entered. This is because both the web.config for the child and parent applications had this key. But this existed for many years like this without change. Why all of sudden its an issue now?

The solution:
The reason this was never a problem is because the keys AND values were always the same. Yesterday we updated our SQL connection strings to include the Application Name in the connection string. This made the string unique and all of sudden started to fail.

Without doing any research on the exact reason for this, I have to assume that when the child application inherits the parents web.config values, it ignores identical key/value pairs.

We were able to solve it by wrapping the connection string like this

    <location path="." inheritInChildApplications="false">
            <!-- Updated connection strings go here -->

Edit: I forgot to mention that I added this in the PARENTS web.config. I didn't have to modify the child's web.config.

Thanks for everyones help on this, saved our butts.

Syntax error: Illegal return statement in JavaScript

in javascript return statement only used inside function block. if you try to use return statement inside independent if else block it trigger syntax error : Illegal return statement in JavaScript

Here is my example code to avoid such error :

<script type = 'text/javascript'>
    var ss= 'no';
        alert('Status return true');   
        alert('Status return false'); 

    function getStatus(ask){
        return true;     
        return false;

Please check Jsfiddle example

"Untrusted App Developer" message when installing enterprise iOS Application

For iOS 13.6

Go to settings -> General -> Device Management -> Click on Trust « Apple Development » -> Click on the red trust button and you’re all set! Enjoy

When should an Excel VBA variable be killed or set to Nothing?

VBA uses a garbage collector which is implemented by reference counting.

There can be multiple references to a given object (for example, Dim aw = ActiveWorkbook creates a new reference to Active Workbook), so the garbage collector only cleans up an object when it is clear that there are no other references. Setting to Nothing is an explicit way of decrementing the reference count. The count is implicitly decremented when you exit scope.

Strictly speaking, in modern Excel versions (2010+) setting to Nothing isn't necessary, but there were issues with older versions of Excel (for which the workaround was to explicitly set)

C/C++ include header file order

I'm pretty sure this isn't a recommended practice anywhere in the sane world, but I like to line system includes up by filename length, sorted lexically within the same length. Like so:

#include <set>
#include <vector>
#include <algorithm>
#include <functional>

I think it's a good idea to include your own headers before other peoples, to avoid the shame of include-order dependency.

Origin http://localhost is not allowed by Access-Control-Allow-Origin

I fixed this (for development) with a simple nginx proxy...

# /etc/nginx/sites-enabled/default
server {
  listen 80;
  root /path/to/Development/dir;
  index index.html;

  # from your example
  location /search {

Calling a phone number in swift

Swift 3.0 and ios 10 or older

func phone(phoneNum: String) {
    if let url = URL(string: "tel://\(phoneNum)") {
        if #available(iOS 10, *) {
  , options: [:], completionHandler: nil)
        } else {
            UIApplication.shared.openURL(url as URL)

How can I use a carriage return in a HTML tooltip?

&#xD; <----- This is the text needed to insert Carry Return.

Check if bash variable equals 0

You can try this:

: ${depth?"Error Message"} ## when your depth variable is not even declared or is unset.

NOTE: Here it's just ? after depth.


: ${depth:?"Error Message"} ## when your depth variable is declared but is null like: "depth=". 

NOTE: Here it's :? after depth.

Here if the variable depth is found null it will print the error message and then exit.

Pass parameter from a batch file to a PowerShell script

The answer from @Emiliano is excellent. You can also pass named parameters like so:

powershell.exe -Command 'G:\Karan\PowerShell_Scripts\START_DEV.ps1' -NamedParam1 "SomeDataA" -NamedParam2 "SomeData2"

Note the parameters are outside the command call, and you'll use:


difference between $query>num_rows() and $this->db->count_all_results() in CodeIgniter & which one is recommended

$sql = "select count(*) as row from login WHERE firstname = '" . $username . "' AND password = '" . $password . "'";
    $query = $this->db->query($sql);
    if ($query->num_rows() == 1) {
    return true;
    } else {
    return false;

How to check the function's return value if true or false

You don't need to call ValidateForm() twice, as you are above. You can just do

} else ...

I think that will solve the issue as above it looks like your comparing true/false to the string equivalent 'false'.

How to get current domain name in ASP.NET

Here is a quick easy way to just get the name of the url.

            var urlHost = HttpContext.Current.Request.Url.Host;

            var xUrlHost = urlHost.Split('.');
            foreach(var thing in xUrlHost)
                if(thing != "www" && thing != "com")
                    urlHost = thing;

How to align iframe always in the center

First remove position:absolute of div#iframe-wrapper iframe, Remove position:fixed and all other css from div#iframe-wrapper

Then apply this css,

div#iframe-wrapper {
  width: 200px;
  height: 400px;
  margin: 0 auto;


How can I remove item from querystring in using c#?

You're probably going to want use a Regular Expression to find the parameter you want to remove from the querystring, then remove it and redirect the browser to the same file with your new querystring.

WCFTestClient The HTTP request is unauthorized with client authentication scheme 'Anonymous'

Try providing username and password in your client like below

client.ClientCredentials.UserName.UserName = @"Domain\username"; client.ClientCredentials.UserName.Password = "password";

Replace transparency in PNG images with white background

Non-command line option: open the PNG file in Windows Paint and click Save.

How does a Linux/Unix Bash script know its own PID?

If the process is a child process and $BASHPID is not set, it is possible to query the ppid of a created child process of the running process. It might be a bit ugly, but it works. Example:

sleep 1 &
mypid=$(ps -o ppid= -p "$!")

How to pass variable as a parameter in Execute SQL Task SSIS?

In your Execute SQL Task, make sure SQLSourceType is set to Direct Input, then your SQL Statement is the name of the stored proc, with questionmarks for each paramter of the proc, like so:

enter image description here

Click the parameter mapping in the left column and add each paramter from your stored proc and map it to your SSIS variable:

enter image description here

Now when this task runs it will pass the SSIS variables to the stored proc.

Changing navigation bar color in Swift

Swift 3

Simple one liner that you can use in ViewDidLoad()

//Change Color
    self.navigationController?.navigationBar.barTintColor =
//Change Text Color
    self.navigationController?.navigationBar.titleTextAttributes = [NSForegroundColorAttributeName: UIColor.white]

fatal error LNK1104: cannot open file 'libboost_system-vc110-mt-gd-1_51.lib'

In case you have trouble building boost or prefer not to do that, an alternative is to download the lib files from SourceForge. The link will take you to a folder of zipped lib and dll files for version 1.51. But, you should be able to edit the link to specify the version of choice. Apparently the installer from BoostPro has some issues.

Printing the value of a variable in SQL Developer

SQL Developer seems to only output the DBMS_OUTPUT text when you have explicitly turned on the DBMS_OUTPUT window pane.

Go to (Menu) VIEW -> Dbms_output to invoke the pane.

Click on the Green Plus sign to enable output for your connection and then run the code.

EDIT: Don't forget to set the buffer size according to the amount of output you are expecting.

ASP.NET / C#: DropDownList SelectedIndexChanged in server control not firing

Is Viewstate turned on?

Edit: Perhaps you should reconsider overriding the rendering function

  protected override void RenderContents(HtmlTextWriter output)

and instead add the dropdownlists to the control and render the control using the default RenderContents.

Edit: See the answer from Dennis which I alluded to in my previous comment:

Controls.Add ( ddlCountries );
Controls.Add ( ddlStates );

How to create a DataFrame of random integers with Pandas?

The recommended way to create random integers with NumPy these days is to use numpy.random.Generator.integers. (documentation)

import numpy as np
import pandas as pd

rng = np.random.default_rng()
df = pd.DataFrame(rng.integers(0, 100, size=(100, 4)), columns=list('ABCD'))
      A    B    C    D
 0   58   96   82   24
 1   21    3   35   36
 2   67   79   22   78
 3   81   65   77   94
 4   73    6   70   96
... ...  ...  ...  ...
95   76   32   28   51
96   33   68   54   77
97   76   43   57   43
98   34   64   12   57
99   81   77   32   50
100 rows × 4 columns

How to copy part of an array to another array in C#?

int[] b = new int[3];
Array.Copy(a, 1, b, 0, 3);
  • a = source array
  • 1 = start index in source array
  • b = destination array
  • 0 = start index in destination array
  • 3 = elements to copy

Force unmount of NFS-mounted directory

If the NFS server disappeared and you can't get it back online, one trick that I use is to add an alias to the interface with the IP of the NFS server (in this example,


The command for that is something roughly like:

ifconfig eth0:fakenfs netmask

Where is the IP of the NFS server that went away. You should then be able to ping the address, and you should also be able to unmount the filesystem (use unmount -f). You should then destroy the aliased interface so you no longer route traffic to the old NFS server to yourself with:

ifconfig eth0:fakenfs down

FreeBSD and similar operating systems

The command would be something like:

ifconfig em0 alias netmask

And then to remove it:

ifconfig em0 delete

man ifconfig(8) for more!

JavaScript OR (||) variable assignment explanation

According to the Bill Higgins' Blog post; the Javascript logical OR assignment idiom (Feb. 2007), this behavior is true as of v1.2 (at least)

He also suggests another use for it (quoted): "lightweight normalization of cross-browser differences"

// determine upon which element a Javascript event (e) occurred
var target = /*w3c*/ || /*IE*/ e.srcElement;

Show Hide div if, if statement is true

This does not need jquery, you could set a variable inside the if and use it in html or pass it thru your template system if any

$query3 = mysql_query($query3);
$numrows = mysql_num_rows($query3);
if ($numrows > 0){
    $fvisit = mysql_fetch_array($result3);
 }else {



later in html

  <div id="results" <?php if ($showDivFlag===false){?>style="display:none"<?php } ?>>

Eclipse: All my projects disappeared from Project Explorer

File - Import - Existing projects into workspace - browse - choose your workspase - done!

How does the SQL injection from the "Bobby Tables" XKCD comic work?

A single quote is the start and end of a string. A semicolon is the end of a statement. So if they were doing a select like this:

Select *
From Students
Where (Name = '<NameGetsInsertedHere>')

The SQL would become:

Select *
From Students
Where (Name = 'Robert'); DROP TABLE STUDENTS; --')
--             ^-------------------------------^

On some systems, the select would get ran first followed by the drop statement! The message is: DONT EMBED VALUES INTO YOUR SQL. Instead use parameters!

How to get a barplot with several variables side by side grouped by a factor

You can plot the means without resorting to external calculations and additional tables using stat_summary(...). In fact, stat_summary(...) was designed for exactly what you are doing.

library(reshape2)            # for melt(...)
gg <- melt(df,id="gender")   # df is your original table
ggplot(gg, aes(x=variable, y=value, fill=factor(gender))) + 
  stat_summary(fun.y=mean, geom="bar",position=position_dodge(1)) + 
               color="grey80",position=position_dodge(1), width=.2)

To add "error bars" you cna also use stat_summary(...) (here, I'm using the min and max value rather than sd because you have so little data).

ggplot(gg, aes(x=variable, y=value, fill=factor(gender))) + 
  stat_summary(fun.y=mean, geom="bar",position=position_dodge(1)) + 
               color="grey40",position=position_dodge(1), width=.2) +

Make REST API call in Swift

You can do like this :

var url : String = ""
var request : NSMutableURLRequest = NSMutableURLRequest()
request.URL = NSURL(string: url)
request.HTTPMethod = "GET"

NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue(), completionHandler:{ (response:NSURLResponse!, data: NSData!, error: NSError!) -> Void in
    var error: AutoreleasingUnsafeMutablePointer<NSError?> = nil
    let jsonResult: NSDictionary! = NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingOptions.MutableContainers, error: error) as? NSDictionary

    if (jsonResult != nil) {
        // process jsonResult
    } else {
       // couldn't load JSON, look at error


EDIT : For people have problem with this maybe your JSON stream is an array [] and not an object {} so you have to change jsonResult to NSArray instead of NSDictionary

How to resize html canvas element?

<div id="canvasdiv" style="margin: 5px; height: 100%; width: 100%;">
    <canvas id="mycanvas" style="border: 1px solid red;"></canvas>
function InitContext()
var $canvasDiv = $('#canvasdiv');

var canvas = document.getElementById("mycanvas");
canvas.height = $canvasDiv.innerHeight();
canvas.width = $canvasDiv.innerWidth();

Where can I set environment variables that crontab will use?

Unfortunately, crontabs have a very limited environment variables scope, thus you need to export them every time the corntab runs.

An easy approach would be the following example, suppose you've your env vars in a file called env, then:

* * * * * . ./env && /path/to_your/command

this part . ./env will export them and then they're used within the same scope of your command

How to delete specific columns with VBA?

You say you want to delete any column with the title "Percent Margin of Error" so let's try to make this dynamic instead of naming columns directly.

Sub deleteCol()

On Error Resume Next

Dim wbCurrent As Workbook
Dim wsCurrent As Worksheet
Dim nLastCol, i As Integer

Set wbCurrent = ActiveWorkbook
Set wsCurrent = wbCurrent.ActiveSheet
'This next variable will get the column number of the very last column that has data in it, so we can use it in a loop later
nLastCol = wsCurrent.Cells.Find("*", LookIn:=xlValues, SearchOrder:=xlByColumns, SearchDirection:=xlPrevious).Column

'This loop will go through each column header and delete the column if the header contains "Percent Margin of Error"
For i = nLastCol To 1 Step -1
    If InStr(1, wsCurrent.Cells(1, i).Value, "Percent Margin of Error", vbTextCompare) > 0 Then
        wsCurrent.Columns(i).Delete Shift:=xlShiftToLeft
    End If
Next i

End Sub

With this you won't need to worry about where you data is pasted/imported to, as long as the column headers are in the first row.

EDIT: And if your headers aren't in the first row, it would be a really simple change. In this part of the code: If InStr(1, wsCurrent.Cells(1, i).Value, "Percent Margin of Error", vbTextCompare) change the "1" in Cells(1, i) to whatever row your headers are in.

EDIT 2: Changed the For section of the code to account for completely empty columns.

WebSockets vs. Server-Sent events/EventSource

Websockets and SSE (Server Sent Events) are both capable of pushing data to browsers, however they are not competing technologies.

Websockets connections can both send data to the browser and receive data from the browser. A good example of an application that could use websockets is a chat application.

SSE connections can only push data to the browser. Online stock quotes, or twitters updating timeline or feed are good examples of an application that could benefit from SSE.

In practice since everything that can be done with SSE can also be done with Websockets, Websockets is getting a lot more attention and love, and many more browsers support Websockets than SSE.

However, it can be overkill for some types of application, and the backend could be easier to implement with a protocol such as SSE.

Furthermore SSE can be polyfilled into older browsers that do not support it natively using just JavaScript. Some implementations of SSE polyfills can be found on the Modernizr github page.


  • SSE suffers from a limitation to the maximum number of open connections, which can be specially painful when opening various tabs as the limit is per browser and set to a very low number (6). The issue has been marked as "Won't fix" in Chrome and Firefox. This limit is per browser + domain, so that means that you can open 6 SSE connections across all of the tabs to and another 6 SSE connections to (thanks Phate).
  • Only WS can transmit both binary data and UTF-8, SSE is limited to UTF-8. (Thanks to Chado Nihi).
  • Some enterprise firewalls with packet inspection have trouble dealing with WebSockets (Sophos XG Firewall, WatchGuard, McAfee Web Gateway).

HTML5Rocks has some good information on SSE. From that page:

Server-Sent Events vs. WebSockets

Why would you choose Server-Sent Events over WebSockets? Good question.

One reason SSEs have been kept in the shadow is because later APIs like WebSockets provide a richer protocol to perform bi-directional, full-duplex communication. Having a two-way channel is more attractive for things like games, messaging apps, and for cases where you need near real-time updates in both directions. However, in some scenarios data doesn't need to be sent from the client. You simply need updates from some server action. A few examples would be friends' status updates, stock tickers, news feeds, or other automated data push mechanisms (e.g. updating a client-side Web SQL Database or IndexedDB object store). If you'll need to send data to a server, XMLHttpRequest is always a friend.

SSEs are sent over traditional HTTP. That means they do not require a special protocol or server implementation to get working. WebSockets on the other hand, require full-duplex connections and new Web Socket servers to handle the protocol. In addition, Server-Sent Events have a variety of features that WebSockets lack by design such as automatic reconnection, event IDs, and the ability to send arbitrary events.

TLDR summary:

Advantages of SSE over Websockets:

  • Transported over simple HTTP instead of a custom protocol
  • Can be poly-filled with javascript to "backport" SSE to browsers that do not support it yet.
  • Built in support for re-connection and event-id
  • Simpler protocol
  • No trouble with corporate firewalls doing packet inspection

Advantages of Websockets over SSE:

  • Real time, two directional communication.
  • Native support in more browsers

Ideal use cases of SSE:

  • Stock ticker streaming
  • twitter feed updating
  • Notifications to browser

SSE gotchas:

  • No binary support
  • Maximum open connections limit

Jquery: Checking to see if div contains text, then action

if( $("#field > div.field-item").text().indexOf('someText') >= 0)

Some browsers will include whitespace, others won't. >= is appropriate here. Otherwise equality is double equals ==

Add to Array jQuery

push is a native javascript method. You could use it like this:

var array = [1, 2, 3];
array.push(4); // array now is [1, 2, 3, 4]
array.push(5, 6, 7); // array now is [1, 2, 3, 4, 5, 6, 7]

How to add noise (Gaussian/salt and pepper etc) to image in Python with OpenCV

just look at cv2.randu() or cv.randn(), it's all pretty similar to matlab already, i guess.

let's play a bit ;) :

import cv2
import numpy as np

>>> im = np.empty((5,5), np.uint8) # needs preallocated input image
>>> im
array([[248, 168,  58,   2,   1],  # uninitialized memory counts as random, too ?  fun ;) 
       [  0, 100,   2,   0, 101],
       [  0,   0, 106,   2,   0],
       [131,   2,   0,  90,   3],
       [  0, 100,   1,   0,  83]], dtype=uint8)
>>> im = np.zeros((5,5), np.uint8) # seriously now.
>>> im
array([[0, 0, 0, 0, 0],
       [0, 0, 0, 0, 0],
       [0, 0, 0, 0, 0],
       [0, 0, 0, 0, 0],
       [0, 0, 0, 0, 0]], dtype=uint8)
>>> cv2.randn(im,(0),(99))         # normal
array([[  0,  76,   0, 129,   0],
       [  0,   0,   0, 188,  27],
       [  0, 152,   0,   0,   0],
       [  0,   0, 134,  79,   0],
       [  0, 181,  36, 128,   0]], dtype=uint8)
>>> cv2.randu(im,(0),(99))         # uniform
array([[19, 53,  2, 86, 82],
       [86, 73, 40, 64, 78],
       [34, 20, 62, 80,  7],
       [24, 92, 37, 60, 72],
       [40, 12, 27, 33, 18]], dtype=uint8)

to apply it to an existing image, just generate noise in the desired range, and add it:

img = ...
noise = ...

image = img + noise

How do I create a crontab through a script

It is an approach to incrementally add the cron job:

  ssh USER_NAME@$PRODUCT_IP nohup "echo '*/2 * * * * ping -c2 >> /var/www/html/test.html' | crontab -u USER_NAME -"

Access Session attribute on jstl

You should definitely avoid using <jsp:...> tags. They're relics from the past and should always be avoided now.

Use the JSTL.

Now, wether you use the JSTL or any other tag library, accessing to a bean property needs your bean to have this property. A property is not a private instance variable. It's an information accessible via a public getter (and setter, if the property is writable). To access the questionPaperID property, you thus need to have a

public SomeType getQuestionPaperID() {

method in your bean.

Once you have that, you can display the value of this property using this code :

<c:out value="${Questions.questionPaperID}" />

or, to specifically target the session scoped attributes (in case of conflicts between scopes) :

<c:out value="${sessionScope.Questions.questionPaperID}" />

Finally, I encourage you to name scope attributes as Java variables : starting with a lowercase letter.

PHP-FPM doesn't write to error log

In your fpm.conf file you haven't set 2 variable which are only for error logging.

The variables are error_log (file path of your error log file) and log_level (error logging level).

; Error log file
; Note: the default prefix is /usr/local/php/var
; Default Value: log/php-fpm.log

error_log = log/php-fpm.log

; Log level
; Possible Values: alert, error, warning, notice, debug
; Default Value: notice

log_level = notice

What is the best way to dump entire objects to a log in C#?

Here is a stupidly simple way to write a flat object, nicely formatted:

using Newtonsoft.Json.Linq;

Debug.WriteLine("The object is " + JObject.FromObject(theObjectToDump).ToString());

What's going on is that the object is first converted to a JSON internal representation by JObject.FromObject, and then converted to JSON string by ToString. (And of course a JSON string is a very nice representation of a simple object, especially since ToString will include newlines and indents.) The "ToString" is of course extraneous (as it's implied by using + to concat a string and an object), but I kinda like to specify it here.

Adding elements to object

function addValueInObject(object, key, value) {
    var res = {};
    var textObject = JSON.stringify(object);
    if (textObject === '{}') {
        res = JSON.parse('{"' + key + '":"' + value + '"}');
    } else {
        res = JSON.parse('{' + textObject.substring(1, textObject.length - 1) + ',"' + key + '":"' + value + '"}');
    return res;

this code is worked.

Append column to pandas dataframe

Both join() and concat() way could solve the problem. However, there is one warning I have to mention: Reset the index before you join() or concat() if you trying to deal with some data frame by selecting some rows from another DataFrame.

One example below shows some interesting behavior of join and concat:

dat1 = pd.DataFrame({'dat1': range(4)})
dat2 = pd.DataFrame({'dat2': range(4,8)})
dat1.index = [1,3,5,7]
dat2.index = [2,4,6,8]

# way1 join 2 DataFrames
# output
   dat1  dat2
1     0   NaN
3     1   NaN
5     2   NaN
7     3   NaN

# way2 concat 2 DataFrames
   dat1  dat2
1   0.0   NaN
2   NaN   4.0
3   1.0   NaN
4   NaN   5.0
5   2.0   NaN
6   NaN   6.0
7   3.0   NaN
8   NaN   7.0

#reset index 
dat1 = dat1.reset_index(drop=True)
dat2 = dat2.reset_index(drop=True)
#both 2 ways to get the same result

   dat1  dat2
0     0     4
1     1     5
2     2     6
3     3     7

   dat1  dat2
0     0     4
1     1     5
2     2     6
3     3     7

Visual Studio Code: format is not using indent settings

Most likely you have some formatting extension installed, e.g. JS-CSS-HTML Formatter.

If it is the case, then just open Command Palette, type "Formatter" and select Formatter Config. Then edit the value of "indent_size" as you like.

P.S. Don't forget to restart Visual Studio Code after editing :)

Where can I download IntelliJ IDEA Color Schemes?

I know I'm late to the party but just wanted to mention that the Jumpout II theme really is amazing.. I have a lot of themes and this one really is great for a # of reasons..

  1. it handles glare very well (yes even pure black on matte screens can produce glare, unfortunately my new matte monitor - has a more "glary" coating than my old one).. this is a grayish-black background

  2. it has enough colors that you can easily see read even dense code - some themes that look nice at first use too much of one color and it makes dense code harder to digest

  3. the comments are all gray, this is even better than dark green which is my 2nd favorite choice.. it really helps the code pop out..

so basically this is a great anti-glare, anti-dense-code theme

honorable mentions (I think these all can be found on that same site, although I'm not sure I spelled all of them correctly)

  1. Dark Flash Builder (really great but at first the use of red can be confusing, but it is really one of its strengths. I had to modify it to make my error text highlighting different - I settled on some bright red underlined text)
  2. Gedit Original Oblivion
  3. Leone Dark II
  4. Visual Studio 2013
  5. Retta (very halloweeny)

and for white / beige / blue (in that order)

  1. Oughsumm (wow best white ever, possibly the most legible theme I've ever seen - however, white is too bright for me in my current office situation, although occasionally I do switch to this when I want to quickly review a lot of code before a commit), also it is comfortably legible at 1 point smaller than all dark themes I've used.
  2. humane-ist
  3. rubyblue

p.s. please note I change the font of all the themes I use to Consolas 11 or 12 depending on the monitor. Consolas I find to be the best programming font out there. It looks great, easy to read and very well suited to LCD anti-aliasing. I tried so many programming fonts but I always come back to this one quickly. And it is not too narrow.. I'm not in the narrow camp, I believe narrow font aficionados don't program with ultra wide monitors - maybe program on a macbook or something just as bad :)

p.p.s I know solarized is supposed to be some kind of ultimate, magical, life-enhancing nirvana-inducing theme but I just don't get it.. I tried but failed to find it anything but annoying

jquery function setInterval

// simple example using the concept of setInterval

var g = $('.jumping');
function blink(){
  g.animate({ 'left':'50px' 

Laravel Migration Change to Make a Column Nullable

Adding to Dmitri Chebotarev's answer, as for Laravel 5+.

After requiring the doctrine/dbal package:

composer require doctrine/dbal

You can then make a migration with nullable columns, like so:

public function up()
    Schema::table('users', function (Blueprint $table) {
        // change() tells the Schema builder that we are altering a table

To revert the operation, do:

public function down()
    /* turn off foreign key checks for a moment */
    DB::statement('SET FOREIGN_KEY_CHECKS = 0');
    /* set null values to 0 first */
    DB::statement('UPDATE `users` SET `user_id` = 0 WHERE `user_id` IS NULL;');
    /* alter table */
    DB::statement('ALTER TABLE `users` MODIFY `user_id` INTEGER UNSIGNED NOT NULL;');
    /* finally turn foreign key checks back on */
    DB::statement('SET FOREIGN_KEY_CHECKS = 1');

How Can I Resolve:"can not open 'git-upload-pack' " error in eclipse?

I was getting the same issue "Cannot open git-upload-pack" in eclipse Juno while trying to clone ('Git Repository Exploring' perspective). https://[username]@[hostName]:[portNumber]/scm/TestRepo.git

Solution : Issue got solved after adding "-Dhttps.protocols=TLSv1" to the eclipse.ini file.

Possible Reason for Error : Some servers does not support TLSv1.2, or TLSv1.1, they might support only TLSv1.0. Java 8 default TLS protocol is 1.2 whereas it is 1.0 with Java 7. For an unknown reason, when Egit connects to the server, it does not fallback to TLSv1.1 after TLS1.2 fails to establish the connection. Don't know if it's an Egit or a Java 8 issue Courtesy :

Paste a multi-line Java String in Eclipse

The EclipsePasteAsJavaString plug-in allows you to insert text as a Java string by Ctrl + Shift + V


Paste as usual via Ctrl+V:

some text with tabs and new lines

Paste as Java string via Ctrl+Shift+V

"some text\twith tabs\r\n" + "and new \r\n" + "lines"

Label points in geom_point

Instead of using the ifelse as in the above example, one can also prefilter the data prior to labeling based on some threshold values, this saves a lot of work for the plotting device:

xlimit <- 36
ylimit <- 24
    geom_label(data=myData[myData$myX > xlimit & myData$myY> ylimit,], aes(myX,myY,myLabel))

What are metaclasses in Python?

The type() function can return the type of an object or create a new type,

for example, we can create a Hi class with the type() function and do not need to use this way with class Hi(object):

def func(self, name='mike'):
    print('Hi, %s.' % name)

Hi = type('Hi', (object,), dict(hi=func))
h = Hi()
Hi, mike.



In addition to using type() to create classes dynamically, you can control creation behavior of class and use metaclass.

According to the Python object model, the class is the object, so the class must be an instance of another certain class. By default, a Python class is instance of the type class. That is, type is metaclass of most of the built-in classes and metaclass of user-defined classes.

class ListMetaclass(type):
    def __new__(cls, name, bases, attrs):
        attrs['add'] = lambda self, value: self.append(value)
        return type.__new__(cls, name, bases, attrs)

class CustomList(list, metaclass=ListMetaclass):

lst = CustomList()

['custom_list_1', 'custom_list_2']

Magic will take effect when we passed keyword arguments in metaclass, it indicates the Python interpreter to create the CustomList through ListMetaclass. new (), at this point, we can modify the class definition, for example, and add a new method and then return the revised definition.

Arrays in cookies PHP

To store the array values in cookie, first you need to convert them to string, so here is some options.

Storing cookies as JSON

Storing code

setcookie('your_cookie_name', json_encode($info), time()+3600);

Reading code

$data = json_decode($_COOKIE['your_cookie_name'], true);

JSON can be good choose also if you need read cookie in front end with JavaScript.

Actually you can use any encrypt_array_to_string/decrypt_array_from_string methods group that will convert array to string and convert string back to same array. For example you can also use explode/implode for array of integers.

Warning: Do not use serialize/unserialize


enter image description here

Do not pass untrusted user input to unserialize(). - Anything that coming by HTTP including cookies is untrusted!

References related to security

As an alternative solution, you can do it also without converting array to string.

setcookie('my_array[0]', 'value1' , time()+3600);
setcookie('my_array[1]', 'value2' , time()+3600);
setcookie('my_array[2]', 'value3' , time()+3600);

And after if you will print $_COOKIE variable, you will see the following

echo '<pre>';
print_r( $_COOKIE );
    [my_array] => Array
            [0] => value1
            [1] => value2
            [2] => value3


This is documented PHP feature.


Cookies names can be set as array names and will be available to your PHP scripts as arrays but separate cookies are stored on the user's system.

How to hide collapsible Bootstrap 4 navbar on click

I am using ANGULAR and since it gave me problems the routerLink just add the data-toggle and target in the li tag.... or use jquery like "ZimSystem"

<div class="collapse navbar-collapse" id="navbarSupportedContent">_x000D_
      <ul class="navbar-nav mr-auto">_x000D_
        <li class="nav-item" data-toggle="collapse" data-target="">_x000D_
          <a class="nav-link" routerLink="/inicio" routerLinkActive="active" >Inicio</a>_x000D_

The data-toggle attributes in Twitter Bootstrap

The presence of this data-attribute tells Bootstrap to switch between visual or a logical states of another element on user interaction.

It is used to show modals, tab content, tooltips and popover menus as well as setting a pressed-state for a toggle-button. It is used in multiple ways without a clear documentation.

Change the background color of CardView programmatically

I finally got the corners to stay. This is c#, Xamarin.Android

in ViewHolder:

CardView = itemView.FindViewById<CardView>(Resource.Id.cdvTaskList);

In Adapter:


C# declare empty string array

Your syntax is invalid.

string[] arr = new string[5];

That will create arr, a referenced array of strings, where all elements of this array are null. (Since strings are reference types)

This array contains the elements from arr[0] to arr[4]. The new operator is used to create the array and initialize the array elements to their default values. In this example, all the array elements are initialized to null.

Single-Dimensional Arrays (C# Programming Guide)

Android view layout_width - how to change programmatically?

try using

View view_instance = (View)findViewById(;

use Layoutparams to do so where you can set width and height like below.

LayoutParams lp = new LayoutParams(10,LayoutParams.wrap_content);

CSS3 transform: rotate; in IE9

I know this is old, but I was having this same issue, found this post, and while it didn't explain exactly what was wrong, it helped me to the right answer - so hopefully my answer helps someone else who might be having a similar problem to mine.

I had an element I wanted rotated vertical, so naturally I added the filter: for IE8 and then the -ms-transform property for IE9. What I found is that having the -ms-transform property AND the filter applied to the same element causes IE9 to render the element very poorly. My solution:

  1. If you are using the transform-origin property, add one for MS too (-ms-transform-origin: left bottom;). If you don't see your element, it could be that it's rotating on it's middle axis and thus leaving the page somehow - so double check that.

  2. Move the filter: property for IE7&8 to a separate style sheet and use an IE conditional to insert that style sheet for browsers less than IE9. This way it doesn't affect the IE9 styles and all should work fine.

  3. Make sure to use the correct DOCTYPE tag as well; if you have it wrong IE9 will not work properly.

How do I get the HTTP status code with jQuery?

I think you should also implement the error function of the $.ajax method.

error(XMLHttpRequest, textStatus, errorThrown)Function

A function to be called if the request fails. The function is passed three arguments: The XMLHttpRequest object, a string describing the type of error that occurred and an optional exception object, if one occurred. Possible values for the second argument (besides null) are "timeout", "error", "notmodified" and "parsererror".

    url: "http://my-ip/test/test.php",
    data: {},
    complete: function(xhr, statusText){
    error: function(xhr, statusText, err){
        alert("Error:" + xhr.status); 

Show Image View from file path?

onLoadImage Full load

private void onLoadImage(final String imagePath) {
    ImageSize targetSize = new ImageSize(imageView.getWidth(), imageView.getHeight()); // result Bitmap will be fit to this size

    //ImageLoader imageLoader = ImageLoader.getInstance(); // Get singleto
    com.nostra13.universalimageloader.core.ImageLoader imageLoader = com.nostra13.universalimageloader.core.ImageLoader.getInstance();

    imageLoader.loadImage(imagePath, targetSize, new SimpleImageLoadingListener() {
        public void onLoadingStarted(final String imageUri, View view) {
            super.onLoadingStarted(imageUri, view);


            new Handler().post(new Runnable() {
                public void run() {
                    progress2.setColorSchemeResources(android.R.color.holo_green_light, android.R.color.holo_orange_light, android.R.color.holo_red_light);

                    // Picasso.with(getContext()).load(imagePath).into(imageView);
                    // Picasso.with(getContext()).load(imagePath) .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE).into(imageView);


        public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
            if (view == null) {
            // else { 
              Log.e("onLoadImage", "onLoadingComplete");
            //   progress2.setVisibility(View.INVISIBLE);
            // }
            // setLoagingCompileImage();

        public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
            super.onLoadingFailed(imageUri, view, failReason);
            if (view == null) {
            Log.e("onLoadingFailed", imageUri);
            Log.e("onLoadingFailed", failReason.toString());

        public void onLoadingCancelled(String imageUri, View view) {
            super.onLoadingCancelled(imageUri, view);
            if (view == null) {
            Log.e("onLoadImage", "onLoadingCancelled");

String, StringBuffer, and StringBuilder

Note that if you are using Java 5 or newer, you should use StringBuilder instead of StringBuffer. From the API documentation:

As of release JDK 5, this class has been supplemented with an equivalent class designed for use by a single thread, StringBuilder. The StringBuilder class should generally be used in preference to this one, as it supports all of the same operations but it is faster, as it performs no synchronization.

In practice, you will almost never use this from multiple threads at the same time, so the synchronization that StringBuffer does is almost always unnecessary overhead.

How can jQuery deferred be used?

Another use that I've been putting to good purpose is fetching data from multiple sources. In the example below, I'm fetching multiple, independent JSON schema objects used in an existing application for validation between a client and a REST server. In this case, I don't want the browser-side application to start loading data before it has all the schemas loaded. $.when.apply().then() is perfect for this. Thank to Raynos for pointers on using then(fn1, fn2) to monitor for error conditions.

fetch_sources = function (schema_urls) {
    var fetch_one = function (url) {
            return $.ajax({
                url: url,
                data: {},
                contentType: "application/json; charset=utf-8",
                dataType: "json",
    return $.map(schema_urls, fetch_one);

var promises = fetch_sources(data['schemas']);
$.when.apply(null, promises).then(

function () {
    var schemas = $.map(arguments, function (a) {
        return a[0]
}, function () {
    console.log("FAIL", this, arguments);

CodeIgniter : Unable to load the requested file:

I error occor. When you are trying to access a file which is not in the director. Carefully check path in the view


default root path of view function is application/view .

I had the same error. I was trying to access files like this


Actually I have the class Pages and function. I built the function with one argument to call the any files from the director application/view/pages . I was put the wrong path. The above path pages/view/files can be used when you are trying to access the controller. Not for the view. MVC gave a lot confusion. I had this problem. I just solve it. Thanks.

Regular expression include and exclude special characters

For the allowed characters you can use

^[a-zA-Z0-9~@#$^*()_+=[\]{}|\\,.?: -]*$

to validate a complete string that should consist of only allowed characters. Note that - is at the end (because otherwise it'd be a range) and a few characters are escaped.

For the invalid characters you can use


to check for them.

To combine both into a single regex you can use

^(?=[a-zA-Z0-9~@#$^*()_+=[\]{}|\\,.?: -]*$)(?!.*[<>'"/;`%])

but you'd need a regex engine that allows lookahead.

How to show progress bar while loading, using ajax

try this it may help you

  beforeSend: function(  ) {
    // load your loading fiel here
  .done(function( data ) {
    //hide your loading file here

How to group by month from Date field using sql

I would use this:

SELECT  Closing_Date = DATEADD(MONTH, DATEDIFF(MONTH, 0, Closing_Date), 0), 
        COUNT(Status) TotalCount 
FROM    MyTable
WHERE   Closing_Date >= '2012-02-01' 
AND     Closing_Date <= '2012-12-31'
AND     Defect_Status1 IS NOT NULL
GROUP BY DATEADD(MONTH, DATEDIFF(MONTH, 0, Closing_Date), 0), Category;

This will group by the first of every month, so

`DATEADD(MONTH, DATEDIFF(MONTH, 0, '20130128'), 0)` 

will give '20130101'. I generally prefer this method as it keeps dates as dates.

Alternatively you could use something like this:

SELECT  Closing_Year = DATEPART(YEAR, Closing_Date),
        Closing_Month = DATEPART(MONTH, Closing_Date),
        COUNT(Status) TotalCount 
FROM    MyTable
WHERE   Closing_Date >= '2012-02-01' 
AND     Closing_Date <= '2012-12-31'
AND     Defect_Status1 IS NOT NULL
GROUP BY DATEPART(YEAR, Closing_Date), DATEPART(MONTH, Closing_Date), Category;

It really depends what your desired output is. (Closing Year is not necessary in your example, but if the date range crosses a year boundary it may be).

What Content-Type value should I send for my XML sitemap?

The difference between text/xml and application/xml is the default character encoding if the charset parameter is omitted:

Text/xml and application/xml behave differently when the charset parameter is not explicitly specified. If the default charset (i.e., US-ASCII) for text/xml is inconvenient for some reason (e.g., bad web servers), application/xml provides an alternative (see "Optional parameters" of application/xml registration in Section 3.2).

For text/xml:

Conformant with [RFC2046], if a text/xml entity is received with the charset parameter omitted, MIME processors and XML processors MUST use the default charset value of "us-ascii"[ASCII]. In cases where the XML MIME entity is transmitted via HTTP, the default charset value is still "us-ascii".

For application/xml:

If an application/xml entity is received where the charset parameter is omitted, no information is being provided about the charset by the MIME Content-Type header. Conforming XML processors MUST follow the requirements in section 4.3.3 of [XML] that directly address this contingency. However, MIME processors that are not XML processors SHOULD NOT assume a default charset if the charset parameter is omitted from an application/xml entity.

So if the charset parameter is omitted, the character encoding of text/xml is US-ASCII while with application/xml the character encoding can be specified in the document itself.

Now a rule of thumb on the internet is: “Be strict with the output but be tolerant with the input.” That means make sure to meet the standards as much as possible when delivering data over the internet. But build in some mechanisms to overlook faults or to guess when receiving and interpreting data over the internet.

So in your case just pick one of the two types (I recommend application/xml) and make sure to specify the used character encoding properly (I recommend to use the respective default character encoding to play safe, so in case of application/xml use UTF-8 or UTF-16).

What causes: "Notice: Uninitialized string offset" to appear?

Check out the contents of your array with

echo '<pre>' . print_r( $arr, TRUE ) . '</pre>';

Show Error on the tip of the Edit Text Android

u can use this :

        public void afterTextChanged(Editable s) {
            if (s.length() == Bank.PAN_MINIMUM_RECOGNIZABLE_LENGTH + 10) {
                Bank bank = BankUtil.findByPan(s.toString());
                if (null != bank && mNewPanEntered && !mNameDefined) {
                    mNewPanEntered = false;

private void suggestCardName(Bank bank) {
    mLastSuggestTime = System.currentTimeMillis();
    if (!bank.getName().trim().matches(getActivity().getString(R.string.bank_eghtesadnovin))) {
        inputCardNumber.setError(R.string.balance_not_enmb, true);


jQuery: Uncheck other checkbox on one checked

Bind a change handler, then just uncheck all of the checkboxes, apart from the one checked:

$('input.example').on('change', function() {
    $('input.example').not(this).prop('checked', false);  

Here's a fiddle

GlobalConfiguration.Configure() not present after Web API 2 and .NET 4.5.1 migration

If the issue remain after uninstalling and installing Microsoft.AspNet.WebApi.WebHost then also add followings in web.config for globalconfiguration to work

        <assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="" newVersion="" />

How to center HTML5 Videos?

I was having the same problem. This worked for me:

.center {
    margin: 0 auto; 
    width: 400px;

How do I use cx_freeze?

I'm really not sure what you're doing to get that error, it looks like you're trying to run cx_Freeze on its own, without arguments. So here is a short step-by-step guide on how to do it in windows (Your screenshot looks rather like the windows command line, so I'm assuming that's your platform)

  1. Write your file. Your script above looks correct so it should work, assuming that your script exists.

  2. Open the command line (Start -> Run -> "cmd")

  3. Go to the location of your file and run python build


  1. There may be a problem with the name of your script. "" contains upper case letters, which might cause confusion since windows' file names are not case sensitive, but python is. My approach is to always use lower case for scripts to avoid any conflicts.

  2. Make sure that python is on your PATH (read

  3. Make sure are are looking at the new cx_Freeze documentation. Google often seems to bring up the old docs.

How can I get input radio elements to horizontally align?

Here is updated Fiddle

Simply remove </br> between input radio's

<div class="clearBoth"></div>
<input type="radio" name="editList" value="always">Always
<input type="radio" name="editList" value="never">Never
<input type="radio" name="editList" value="costChange">Cost Change
<div class="clearBoth"></div>

Java 8 Streams: multiple filters vs. complex condition

The code that has to be executed for both alternatives is so similar that you can’t predict a result reliably. The underlying object structure might differ but that’s no challenge to the hotspot optimizer. So it depends on other surrounding conditions which will yield to a faster execution, if there is any difference.

Combining two filter instances creates more objects and hence more delegating code but this can change if you use method references rather than lambda expressions, e.g. replace filter(x -> x.isCool()) by filter(ItemType::isCool). That way you have eliminated the synthetic delegating method created for your lambda expression. So combining two filters using two method references might create the same or lesser delegation code than a single filter invocation using a lambda expression with &&.

But, as said, this kind of overhead will be eliminated by the HotSpot optimizer and is negligible.

In theory, two filters could be easier parallelized than a single filter but that’s only relevant for rather computational intense tasks¹.

So there is no simple answer.

The bottom line is, don’t think about such performance differences below the odor detection threshold. Use what is more readable.

¹…and would require an implementation doing parallel processing of subsequent stages, a road currently not taken by the standard Stream implementation

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

In JavaScript ES6:

function range(start, end) {_x000D_
  return Array(end - start + 1).fill().map((_, idx) => start + idx)_x000D_
var result = range(9, 18); // [9, 10, 11, 12, 13, 14, 15, 16, 17, 18]_x000D_

For completeness, here it is with an optional step parameter.

function range(start, end, step = 1) {_x000D_
  const len = Math.floor((end - start) / step) + 1_x000D_
  return Array(len).fill().map((_, idx) => start + (idx * step))_x000D_
var result = range(9, 18, 0.83);_x000D_

I would use range-inclusive from npm in an actual project. It even supports backwards steps, so that's cool.

How do I remove time part from JavaScript date?

Parse that string into a Date object:

var myDate = new Date('10/11/1955 10:40:50 AM');

Then use the usual methods to get the date's day of month (getDate) / month (getMonth) / year (getFullYear).

var noTime = new Date(myDate.getFullYear(), myDate.getMonth(), myDate.getDate());

ES6 Class Multiple inheritance

I have been using a pattern like this to program complex multi inheritance things:

var mammal = {
    lungCapacity: 200,
    breath() {return 'Breathing with ' + this.lungCapacity + ' capacity.'}

var dog = {
    catchTime: 2,
    bark() {return 'woof'},
    playCatch() {return 'Catched the ball in ' + this.catchTime + ' seconds!'}

var robot = {
    beep() {return 'Boop'}

var robotDogProto = Object.assign({}, robot, dog, {catchTime: 0.1})
var robotDog = Object.create(robotDogProto)

var livingDogProto = Object.assign({}, mammal, dog)
var livingDog = Object.create(livingDogProto)

This method uses very little code, and allows for things like overwriting default properties (like I do with a custom catchTime in robotDogProto)

Why shouldn't `&apos;` be used to escape single quotes?

If you really need single quotes, apostrophes, you can use

html    | numeric | hex
&lsquo; | &#145;  | &#x91; // for the left/beginning single-quote and
&rsquo; | &#146;  | &#x92; // for the right/ending single-quote

How can I determine browser window size on server side C#

You can use Javascript to get the viewport width and height. Then pass the values back via a hidden form input or ajax.

At its simplest

var width = $(window).width();
var height = $(window).height();

Complete method using hidden form inputs

Assuming you have: JQuery framework.

First, add these hidden form inputs to store the width and height until postback.

<asp:HiddenField ID="width" runat="server" />
<asp:HiddenField ID="height" runat="server" />

Next we want to get the window (viewport) width and height. JQuery has two methods for this, aptly named width() and height().

Add the following code to your .aspx file within the head element.

<script type="text/javascript">
$(document).ready(function() {

    $("#width").val() = $(window).width();
    $("#height").val() = $(window).height();    



This will result in the width and height of the browser window being available on postback. Just access the hidden form inputs like this:

var TheBrowserWidth = width.Value;
var TheBrowserHeight = height.Value;

This method provides the height and width upon postback, but not on the intial page load.

Note on UpdatePanels: If you are posting back via UpdatePanels, I believe the hidden inputs need to be within the UpdatePanel.

Alternatively you can post back the values via an ajax call. This is useful if you want to react to window resizing.

Update for jquery 3.1.1

I had to change the JavaScript to:


JavaScript get clipboard data on paste event (Cross browser)

Solution that works for me is adding event listener to paste event if you are pasting to a text input. Since paste event happens before text in input changes, inside my on paste handler I create a deferred function inside which I check for changes in my input box that happened on paste:

onPaste: function() {
    var oThis = this;
    setTimeout(function() { // Defer until onPaste() is done
        console.log('paste', oThis.input.value);
        // Manipulate pasted input
    }, 1);

Why do I get the "Unhandled exception type IOException"?

add "throws IOException" to your method like this:

public static void main(String args[]) throws  IOException{

        FileReader reader=new FileReader("");

        Properties p=new Properties();


Top 1 with a left join

Because the TOP 1 from the ordered sub-query does not have profile_id = 'u162231993' Remove where = 'u162231993' and see results then.

Run the sub-query separately to understand what's going on.

mysqli::mysqli(): (HY000/2002): Can't connect to local MySQL server through socket 'MySQL' (2)

Please check the following file


The line which bind the host name with ip is probably missing a line which bind them togather  localhost

If the given line is missing. Add the line in the file

Could you also check your MySQL database's user table and tell us the host column value for the user which you are using. You should have user privilege for both the host "" and "localhost" and use % as it is a wild char for generic host name.

Changing datagridview cell color based on condition

You need to do this

private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
    foreach (DataGridViewRow Myrow in dataGridView1.Rows) 
    {            //Here 2 cell is target value and 1 cell is Volume
        if (Convert.ToInt32(Myrow .Cells[2].Value)<Convert.ToInt32(Myrow .Cells[1].Value))// Or your condition 
            Myrow .DefaultCellStyle.BackColor = Color.Red; 
            Myrow .DefaultCellStyle.BackColor = Color.Green; 

Meanwhile also take a look at Cell Formatting

RVM is not a function, selecting rubies with 'rvm use ...' will not work

     Usually this is caused by shell initialization files. Search for PATH=... entries.
     You can also re-add RVM to your profile by running: rvm get stable --auto-dotfiles
     To fix it temporarily in this shell session run: rvm use ruby-2.6.5
     To ignore this error add "rvm_silence_path_mismatch_check_flag=1" to your "~/.rvmrc" file.

Get error message if ModelState.IsValid fails?

If you're looking to generate a single error message string that contains the ModelState error messages you can use SelectMany to flatten the errors into a single list:

if (!ModelState.IsValid)
    var message = string.Join(" | ", ModelState.Values
        .SelectMany(v => v.Errors)
        .Select(e => e.ErrorMessage));
    return new HttpStatusCodeResult(HttpStatusCode.BadRequest, message);

What is the purpose of using -pedantic in GCC/G++ compiler?

<-ansi is an obsolete switch that requests the compiler to compile according to the 30-year-old obsolete revision of C standard, ISO/IEC 9899:1990, which is essentially a rebranding of the ANSI standard X3.159-1989 "Programming Language C. Why obsolete? Because after C90 was published by ISO, ISO has been in charge of the C standardization, and any technical corrigenda to C90 have been standardized by ISO. Thus it is more apt to use the -std=c90.

Without this switch, the recent GCC C compilers will conform to the C language standardized in ISO/IEC 9899:2011, or the newest 2018 revision.

Unfortunately there are some lazy compiler vendors that believe it is acceptable to stick to an older obsolete standard revision, for which the standardization document is not even available from standard bodies.

Using the switch helps ensuring that the code should compile in these obsolete compilers.

The -pedantic is an interesting one. In absence of -pedantic, even when a specific standard is requested, GCC will still allow some extensions that are not acceptable in the C standard. Consider for example the program

struct test {
    int zero_size_array[0];

The C11 draft n1570 paragraph says:

In addition to optional type qualifiers and the keyword static, the [ and ] may delimit an expression or *. If they delimit an expression (which specifies the size of an array), the expression shall have an integer type. If the expression is a constant expression, it shall have a value greater than zero.[...]

The C standard requires that the array length be greater than zero; and this paragraph is in the constraints; the standard says the following

A conforming implementation shall produce at least one diagnostic message (identified in an implementation-defined manner) if a preprocessing translation unit or translation unit contains a violation of any syntax rule or constraint, even if the behavior is also explicitly specified as undefined or implementation-defined. Diagnostic messages need not be produced in other circumstances.9)

However, if you compile the program with gcc -c -std=c90 pedantic_test.c, no warning is produced.

-pedantic causes the compiler to actually comply to the C standard; so now it will produce a diagnostic message, as is required by the standard:

gcc -c -pedantic -std=c90 pedantic_test.c
pedantic_test.c:2:9: warning: ISO C forbids zero-size array ‘zero_size_array’ [-Wpedantic]
     int zero_size_array[0];

Thus for maximal portability, specifying the standard revision is not enough, you must also use -pedantic (or -pedantic-errors) to ensure that GCC actually does comply to the letter of the standard.

The last part of the question was about using -ansi with C++. ANSI never standardized the C++ language - only adopting it from ISO, so this makes about as much sense as saying "English as standardized by France". However GCC still seems to accept it for C++, as stupid as it sounds.

How to use nanosleep() in C? What are `tim.tv_sec` and `tim.tv_nsec`?

I usually use some #define and constants to make the calculation easy:

#define NANO_SECOND_MULTIPLIER  1000000  // 1 millisecond = 1,000,000 Nanoseconds

Hence my code would look like this:

timespec sleepValue = {0};

sleepValue.tv_nsec = INTERVAL_MS;
nanosleep(&sleepValue, NULL);

Refresh Fragment at reload

I think you want to refresh the fragment contents upon db update

If so, detach the fragment and reattach it

// Reload current fragment
Fragment frg = null;
frg = getSupportFragmentManager().findFragmentByTag("Your_Fragment_TAG");
final FragmentTransaction ft = getSupportFragmentManager().beginTransaction();

Your_Fragment_TAG is the name you gave your fragment when you created it

This code is for support library.

If you're not supporting older devices, just use getFragmentManager instead of getSupportFragmentManager


This method requires the Fragment to have a tag.
In case you don't have it, then @Hammer's method is what you need.

Foreach value from POST from form

i wouldn't do it this way

I'd use name arrays in the form elements

so i'd get the layout

$_POST['field'][0]['name'] = 'value';
$_POST['field'][0]['price'] = 'value';
$_POST['field'][1]['name'] = 'value';
$_POST['field'][1]['price'] = 'value';

then you could do an array slice to get the amount you need

JFrame: How to disable window resizing?

Use setResizable on your JFrame


But extending JFrame is generally a bad idea.

What is the difference between properties and attributes in HTML?

After reading Sime Vidas's answer, I searched more and found a very straight-forward and easy-to-understand explanation in the angular docs.

HTML attribute vs. DOM property


Attributes are defined by HTML. Properties are defined by the DOM (Document Object Model).

  • A few HTML attributes have 1:1 mapping to properties. id is one example.

  • Some HTML attributes don't have corresponding properties. colspan is one example.

  • Some DOM properties don't have corresponding attributes. textContent is one example.

  • Many HTML attributes appear to map to properties ... but not in the way you might think!

That last category is confusing until you grasp this general rule:

Attributes initialize DOM properties and then they are done. Property values can change; attribute values can't.

For example, when the browser renders <input type="text" value="Bob">, it creates a corresponding DOM node with a value property initialized to "Bob".

When the user enters "Sally" into the input box, the DOM element value property becomes "Sally". But the HTML value attribute remains unchanged as you discover if you ask the input element about that attribute: input.getAttribute('value') returns "Bob".

The HTML attribute value specifies the initial value; the DOM value property is the current value.

The disabled attribute is another peculiar example. A button's disabled property is false by default so the button is enabled. When you add the disabled attribute, its presence alone initializes the button's disabled property to true so the button is disabled.

Adding and removing the disabled attribute disables and enables the button. The value of the attribute is irrelevant, which is why you cannot enable a button by writing <button disabled="false">Still Disabled</button>.

Setting the button's disabled property disables or enables the button. The value of the property matters.

The HTML attribute and the DOM property are not the same thing, even when they have the same name.

How to select an element by classname using jqLite?

Essentially, and as-noted by @kevin-b:

// find('#id')

//find('.classname'), assumes you already have the starting elem to search from

Note: If you're looking to do this from your controllers you may want to have a look at the "Using Controllers Correctly" section in the developers guide and refactor your presentation logic into appropriate directives (such as <a2b ...>).

Disable a Button

Let's say in Swift 4 you have a button set up for a segue as an IBAction like this @IBAction func nextLevel(_ sender: UIButton) {} and you have other actions occurring within your app (i.e. a timer, gamePlay, etc.). Rather than disabling the segue button, you might want to give your user the option to use that segue while the other actions are still occurring and WITHOUT CRASHING THE APP. Here's how:

var appMode = 0

@IBAction func mySegue(_ sender: UIButton) {

    if appMode == 1 {  // avoid crash if button pressed during other app actions and/or conditions
        let conflictingAction = sender as UIButton
        conflictingAction.isEnabled = false

Please note that you will likely have other conditions within if appMode == 0 and/or if appMode == 1 that will still occur and NOT conflict with the mySegue button. Thus, AVOIDING A CRASH.

No connection could be made because the target machine actively refused it

Add new WebProxy() for the proxy setting , where you are creating a web request.

Example :-

  string url =  "Your URL";
  System.Net.WebRequest req = System.Net.WebRequest.Create(url);
  req.Proxy = new WebProxy();
  System.Net.WebResponse resp = req.GetResponse();

Where req.Proxy = new WebProxy() handle the proxy setting & helps the code to work fine.

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'

in my case, I had a line Class.forName("com.mysql.jdbc.Driver"); after removing this line code works fine if you have any line for loading "com.mysql.jdbc.Driver" remove it, it doesn't require any more

How to turn off caching on Firefox?

The Web Developer Toolbar has an option to disable caching which makes it very easy to turn it on and off when you need it.

Sending commands and strings to with Applescript

I could be mistaken, but I think Applescript Terminal integration is a one-shot deal...That is, each do script call is like opening a different terminal window, so I don't think you can interact with it at all.

You could copy over the SSH public keys to prevent the password prompt, then execute all the commands joined together (warning: the following is totally untested):

tell application "Terminal"
    do script "ssh [email protected] '/home/jdoe/ && /home/jdoe/'"
end tell

Alternatively, you could wrap the ssh and subsequent commands in a shell script using Expect, and then call said shell script from your Applescript.

How do I install a pip package globally instead of locally?

Maybe --force-reinstall would work, otherwise --ignore-installed should do the trick.

jQuery.inArray(), how to use it right?

Just no one use $ instead of jQuery:

if ($.inArray(, array)>=0){
   console.log("is in array");
   console.log("is not in array");

Pipe output and capture exit status in Bash

Base on @brian-s-wilson 's answer; this bash helper function:

pipestatus() {
  local S=("${PIPESTATUS[@]}")

  if test -n "$*"
  then test "$*" = "${S[*]}"
  else ! [[ "${S[@]}" =~ [^0\ ] ]]

used thus:

1: get_bad_things must succeed, but it should produce no output; but we want to see output that it does produce

get_bad_things | grep '^'
pipeinfo 0 1 || return

2: all pipeline must succeed

thing | something -q | thingy
pipeinfo || return

How to bring view in front of everything?

bringToFront() is the right way, but, NOTE that you must call bringToFront() and invalidate() method on highest-level view (under your root view), for e.g.:

Your view's hierarchy is:


So, when you animate back your buttons (1->6), your buttons will under (below) the ImageView. To bring it over (above) the ImageView you must call bringToFront() and invalidate() method on your LinearLayouts. Then it will work :) **NOTE: Remember to set android:clipChildren="false" for your root layout or animate-view's gradparent_layout. Let's take a look at my real code:


<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android=""
    android:orientation="vertical" >

        hw:titleText="@string/app_name" >

        android:clipChildren="false" >

            android:orientation="horizontal" >

            android:src="@drawable/ic_launcher" />

            android:orientation="horizontal" >


Some code in .java

private LinearLayout layoutTop, layoutBottom;
layoutTop = (LinearLayout) rootView.findViewById(;
layoutBottom = (LinearLayout) rootView.findViewById(;
//when animate back
//dragedView is my layoutTop's child view (i added programmatically) (like buttons in above example) 
dragedView.startAnimation(animation); // TranslateAnimation


How to convert a NumPy array to PIL image applying matplotlib colormap

The method described in the accepted answer didn't work for me even after applying changes mentioned in its comments. But the below simple code worked:

import matplotlib.pyplot as plt
plt.imsave(filename, np_array, cmap='Greys')

np_array could be either a 2D array with values from 0..1 floats o2 0..255 uint8, and in that case it needs cmap. For 3D arrays, cmap will be ignored.

failed to open stream: No such file or directory in

include() needs a full file path, relative to the file system's root directory.

This should work:


How can I change the text inside my <span> with jQuery?

Try this

$("#abc").html('<span class = "xyz"> SAMPLE TEXT</span>');

Handle all the css relevant to that span within xyz

Calling a JavaScript function named in a variable

This is kinda ugly, but its the first thing that popped in my head. This also should allow you to pass in arguments:

eval('var myfunc = ' + variable);  myfunc(args, ...);

If you don't need to pass in arguments this might be simpler.

eval(variable + '();');

Standard dry-code warning applies.

how to display excel sheet in html page

Note that Office Web Components are dead, see does-office-xp-web-components-compatable-with-windows-7. OWC was discontinued from XP onward for security reasons.

Since then, and only recently, Microsoft pushes Excel Web App as alternative (a poor alternative IMHO)

As a side note: Microsoft also deprecated the other way round, i.e. embedding the webbrowser control into an excel sheet, see adding-web-browser-control-to-excel-2013. As an alternative Microsoft offers Office Apps (a very limited alternative with respect to interfacing Excel and IE)

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

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

How to reload a page after the OK click on the Alert Page

Bojan Milic answer work in a way but it error out with a message below,

enter image description here

This can be avoid with,

function message() 
alert("Successful message");
window.location = 'url_Of_Redirected_Page' // i.e. window.location='default.aspx'

Network tools that simulate slow network connection

For Linux or OSX, you can use ipfw.

From Quora (

Essentially using a firewall to throttle all network data:

Define a rule that uses a pipe to reroute all traffic from any source address to any destination address, execute the following command (as root, or using sudo):

$ ipfw add pipe 1 all from any to any

To configure this rule to limit bandwidth to 300Kbit/s and impose 200ms of latency each way:

$ ipfw pipe 1 config bw 300Kbit/s delay 200ms

To remove all rules and recover your original network connection:

$ ipfw flush

How can I print a circular structure in a JSON-like format?

Based on the other answers I end up with the following code. It works pretty well with circular references, objects with custom constructors.

From the given object to be serialized,

  • Cache all the object you come across while traversing the object and assign each of them a unique hashID (an auto-incrementing number also works)
  • Once a circular reference is found mark that field in the new object as circular and store the hashID of the original object as an attribute.

Github Link - DecycledJSON

DJSHelper = {};
DJSHelper.Cache = [];
DJSHelper.currentHashID = 0;
DJSHelper.ReviveCache = [];

function DJSNode(name, object, isRoot){ = name;
    // [ATTRIBUTES] contains the primitive fields of the Node
    this.attributes = {};

    // [CHILDREN] contains the Object/Typed fields of the Node
    // All [CHILDREN] must be of type [DJSNode]
    this.children = []; //Array of DJSNodes only

    // If [IS-ROOT] is true reset the Cache and currentHashId
    // before encoding
    isRoot = typeof isRoot === 'undefined'? true:isRoot;
    this.isRoot = isRoot;
        DJSHelper.Cache = [];
        DJSHelper.currentHashID = 0;

        // CACHE THE ROOT
        object.hashID = DJSHelper.currentHashID++;

    for(var a in object){
            var val = object[a];

            if (typeof val === 'object') {
                // IF OBJECT OR NULL REF.

                if(val !== null) {
                    if (DJSHelper.Cache.indexOf(val) === -1) {
                        // VAL NOT IN CACHE
                        val.hashID = DJSHelper.currentHashID++;
                        //console.log("Assigned", val.hashID, "to", a);

                        if (!(val instanceof Array)) {
                            // VAL NOT AN [ARRAY]
                            try {
                                this.children.push(new DJSNode(a, val, false));
                            } catch (err) {
                                console.log(err.message, a);
                                throw err;
                        } else {
                            // VAL IS AN [ARRAY]
                            var node = new DJSNode(a, {
                                array: true,
                                hashID: val.hashID // HashID of array
                            }, false);
                            val.forEach(function (elem, index) {
                                node.children.push(new DJSNode("elem", {val: elem}, false));
                    } else {
                        // VAL IN CACHE
                        // ADD A CYCLIC NODE WITH HASH-ID
                        this.children.push(new DJSNode(a, {
                            cyclic: true,
                            hashID: val.hashID
                        }, false));
                    // PUT NULL AS AN ATTRIBUTE
                    this.attributes[a] = 'null';
            } else if (typeof val !== 'function') {
                // MUST BE A PRIMITIVE
                // ADD IT AS AN ATTRIBUTE
                this.attributes[a] = val;

        DJSHelper.Cache = null;
    this.constructorName =;
DJSNode.Revive = function (xmlNode, isRoot) {
    // Default value of [isRoot] is True
    isRoot = typeof isRoot === 'undefined'?true: isRoot;
    var root;
        DJSHelper.ReviveCache = []; //Garbage Collect
    if(window[xmlNode.constructorName].toString().indexOf('[native code]') > -1 ) {
        // yep, native in the browser
        if(xmlNode.constructorName == 'Object'){
            root = {};
            return null;
    }else {
        eval('root = new ' + xmlNode.constructorName + "()");

    DJSHelper.ReviveCache[xmlNode.attributes.hashID] = root;

    for(var k in xmlNode.attributes){
        if(xmlNode.attributes.hasOwnProperty(k)) {
            var a = xmlNode.attributes[k];
            if(a == 'null'){
                root[k] = null;
            }else {
                root[k] = a;

    xmlNode.children.forEach(function (value) {
        // Each children is an [DJSNode]
        // [Array]s are stored as [DJSNode] with an positive Array attribute
        // So is value

            // ITS AN [ARRAY]
            root[] = [];
            value.children.forEach(function (elem) {
            //console.log("Caching", value.attributes.hashID);
            DJSHelper.ReviveCache[value.attributes.hashID] = root[];
        }else if(!value.attributes.cyclic){
            // ITS AN [OBJECT]
            root[] = DJSNode.Revive(value, false);
            //console.log("Caching", value.attributes.hashID);
            DJSHelper.ReviveCache[value.attributes.hashID] = root[];

    xmlNode.children.forEach(function (value) {
        // Each children is an [DJSNode]
        // [Array]s are stored as [DJSNode] with an positive Array attribute
        // So is value

            root[] = DJSHelper.ReviveCache[value.attributes.hashID];

        DJSHelper.ReviveCache = null; //Garbage Collect
    return root;

DecycledJSON = {};
DecycledJSON.stringify = function (obj) {
    return JSON.stringify(new DJSNode("root", obj));
DecycledJSON.parse = function (json, replacerObject) {
    // use the replacerObject to get the null values
    return DJSNode.Revive(JSON.parse(json));
DJS = DecycledJSON;

Example Usage 1:

var obj = {
    box: {
        owner: null,
        key: 'storm'

console.log(obj); // ORIGINAL

var jsonObj = DJS.stringify(obj);

Example Usage 2:


function Person() { = null;
    this.child = null; = null; = null;
var Dad = new Person(); = 'John';
var Mom = new Person(); = 'Sarah';
var Child = new Person(); = 'Kiddo';

Dad.child = Mom.child = Child; = Dad; = Mom;

console.log(Child); // ORIGINAL

var jsonChild = DJS.stringify(Child);

Nodejs cannot find installed module on Windows

To make it short, use npm link jade in your app directory.

Partition Function COUNT() OVER possible using DISTINCT

I think the only way of doing this in SQL-Server 2008R2 is to use a correlated subquery, or an outer apply:

SELECT  datekey,
        COALESCE(RunningTotal, 0) AS RunningTotal,
        COALESCE(RunningCount, 0) AS RunningCount,
        COALESCE(RunningDistinctCount, 0) AS RunningDistinctCount
FROM    document
        (   SELECT  SUM(Amount) AS RunningTotal,
                    COUNT(1) AS RunningCount,
                    COUNT(DISTINCT d2.dateKey) AS RunningDistinctCount
            FROM    Document d2
            WHERE   d2.DateKey <= document.DateKey
        ) rt;

This can be done in SQL-Server 2012 using the syntax you have suggested:

SELECT  datekey,
        SUM(Amount) OVER(ORDER BY DateKey) AS RunningTotal
FROM    document

However, use of DISTINCT is still not allowed, so if DISTINCT is required and/or if upgrading isn't an option then I think OUTER APPLY is your best option

In SSRS, why do I get the error "item with same key has already been added" , when I'm making a new report?

I face the same issue. After debug I fixed the same. if the column name in your sql query has multiple times then this issue occur. Hence use alias in sql query to differ the column name. Ex: The below query will work proper in sql query but create issue in SSRS report:

Select P.ID, P.FirstName, P.LastName, D.ID, D.City, D.Area, D.Address From PersonalDetails P Left Join CommunicationDetails D On P.ID = D.PersonalDetailsID

Reason : ID has mentioned twice (Multiple Times)

Correct Query:

Select P.ID As PersonalDetailsID, P.FirstName, P.LastName, D.ID, D.City, D.Area, D.Address From PersonalDetails P Left Join CommunicationDetails D On P.ID = D.PersonalDetailsID

Create list or arrays in Windows Batch

Yes, you may use both ways. If you just want to separate the elements and show they in separated lines, a list is simpler:

set list=A B C D

A list of values separated by space may be easily processed by for command:

(for %%a in (%list%) do (
   echo %%a
)) > theFile.txt

You may also create an array this way:

setlocal EnableDelayedExpansion
set n=0
for %%a in (A B C D) do (
   set vector[!n!]=%%a
   set /A n+=1

and show the array elements this way:

(for /L %%i in (0,1,3) do (
   echo !vector[%%i]!
)) > theFile.txt

For further details about array management in Batch files, see: Arrays, linked lists and other data structures in cmd.exe (batch) script

ATTENTION! You must know that all characters included in set command are inserted in the variable name (at left of equal sign), or in the variable value. For example, this command:

set list = "A B C D"

create a variable called list (list-space) with the value "A B C D" (space, quote, A, etc). For this reason, it is a good idea to never insert spaces in set commands. If you need to enclose the value in quotes, you must enclose both the variable name and its value:

set "list=A B C D"

PS - You should NOT use ECHO. in order to left blank lines! An alternative is ECHO/. For further details about this point, see:

How can one run multiple versions of PHP 5.x on a development LAMP server?

For testing I just run multiple instances of httpd on different IP addresses, so I have php7 running on and php5.6 running on In production I have a site running an old oscommerce running php5.3 and I just have a different conf file for the site

httpd -f /etc/apache2/php70.conf
httpd -f /etc/apache2/php53.conf

It's also a clean way to have different php.ini files for different sites. If you just have a couple of sites if a nice way to keep things organized and you don't have to worry about more then 1 site at a time when you upgrade something

How to remove non UTF-8 characters from text file

This command:

iconv -f utf-8 -t utf-8 -c file.txt

will clean up your UTF-8 file, skipping all the invalid characters.

-f is the source format
-t the target format
-c skips any invalid sequence

jQuery function to get all unique elements from an array?

Walk the array and push items into a hash as you come across them. Cross-reference the hash for each new element.

Note that this will ONLY work properly for primitives (strings, numbers, null, undefined, NaN) and a few objects that serialize to the same thing (functions, strings, dates, possibly arrays depending on content). Hashes in this will collide as they all serialize to the same thing, e.g. "[object Object]"

Array.prototype.distinct = function(){
   var map = {}, out = [];

   for(var i=0, l=this.length; i<l; i++){
      if(map[this[i]]){ continue; }

      map[this[i]] = 1;

   return out;

There's also no reason you can't use jQuery.unique. The only thing I don't like about it is that it destroys the ordering of your array. Here's the exact code for it if you're interested:

Sizzle.uniqueSort = function(results){
    if ( sortOrder ) {
        hasDuplicate = baseHasDuplicate;

        if ( hasDuplicate ) {
            for ( var i = 1; i < results.length; i++ ) {
                if ( results[i] === results[i-1] ) {
                    results.splice(i--, 1);

    return results;

MySQL show status - active or total connections?

In order to check the maximum allowed connections, you can run the following query:

SHOW VARIABLES LIKE "max_connections";

To check the number of active connections, you can run the following query:

SHOW VARIABLES LIKE "max_used_connections";

Hope it helps.

Element-wise addition of 2 lists?

[list1[i] + list2[i] for i in range(len(list1))]

PHP Get Highest Value from Array

You could use max() for getting the largest value, but it will return just a value without an according index of array. Then, you could use array_search() to find the according key.

$array = array("a"=>1,"b"=>2,"c"=>4,"d"=>5);
$maxValue = max($array);
$maxIndex = array_search(max($array), $array);
var_dump($maxValue, $maxIndex);


int 5
string 'd' (length=1)

If there are multiple elements with the same value, you'll have to loop through array to get all the keys.

It's difficult to suggest something good without knowing the problem. Why do you need it? What is the input, what is the desired output?

How to watch for form changes in Angular

UPD. The answer and demo are updated to align with latest Angular.

You can subscribe to entire form changes due to the fact that FormGroup representing a form provides valueChanges property which is an Observerable instance:

this.form.valueChanges.subscribe(data => console.log('Form changes', data));

In this case you would need to construct form manually using FormBuilder. Something like this:

export class App {
  constructor(private formBuilder: FormBuilder) {
    this.form ={
      firstName: 'Thomas',
      lastName: 'Mann'

    this.form.valueChanges.subscribe(data => {
      console.log('Form changes', data)
      this.output = data

Check out valueChanges in action in this demo:

How to implement the Java comparable interface?

You would need to implement the interface and define the compareTo() method. For a good tutorial go to - Tutorials point link or MyKongLink

Get first 100 characters from string, respecting full words

This function shortens a string by adding "..." at a word boundary whenever possible. The returned string will have a maximum length of $len including "...".

function truncate($str, $len) {
  $tail = max(0, $len-10);
  $trunk = substr($str, 0, $tail);
  $trunk .= strrev(preg_replace('~^..+?[\s,:]\b|^...~', '...', strrev(substr($str, $tail, $len-$tail))));
  return $trunk;

Examples outputs:

  • truncate("Thanks for contributing an answer to Stack Overflow!", 15)
    returns "Thanks for..."
  • truncate("To learn more, see our tips on writing great answers.", 15)
    returns "To learn more..." (comma also truncated)
  • truncate("Pseudopseudohypoparathyroidism", 15)
    returns "Pseudopseudo..."

How to connect to a remote MySQL database with Java?

to access database from remote machine , you need to give grant all privileges to you data base.

run the following script to give permissions: GRANT ALL PRIVILEGES ON . TO user@'%' IDENTIFIED BY 'password';

git returns http error 407 from proxy after CONNECT

What worked for me is something similar to what rohitmohta is proposing ; in regular DOS command prompt (not on git bash) :


git config --global http.proxy http://username:password@proxiURL:proxiPort

and in some cases also

git config --global https.proxy http://username:password@proxiURL:proxiPort


git config --global http.sslVerify false

(I confirm it's necessary : if set to true getting "SSL certificate problem: unable to get local issuer certificate" error)

in my case, no need of defining all_proxy variable

and finally

git clone

Getting datarow values into a string?

Your rows object holds an Item attribute where you can find the values for each of your columns. You can not expect the columns to concatenate themselves when you do a .ToString() on the row. You should access each column from the row separately, use a for or a foreach to walk the array of columns.

Here, take a look at the class:

java.lang.UnsupportedClassVersionError: Bad version number in .class file?

I also got the same error. Reason for that I was compiling the project using Maven. I had JAVA_HOME pointing to JDK7 and hence java 1.7 was being used for compilation and when running the project I was using JDK1.5. Changing the below entry in .classpath file or change in the eclipse as in the screenshot resolved the issue.

classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/J2SE-1.5

or change in the run configuarions of eclipse as enter image description here

How can I store and retrieve images from a MySQL database using PHP?

My opinion is, Instead of storing images directly to the database, It is recommended to store the image location in the database. As we compare both options, Storing images in the database is safe for security purpose. Disadvantage are

  1. If database is corrupted, no way to retrieve.

  2. Retrieving image files from db is slow when compare to other option.

On the other hand, storing image file location in db will have following advantages.

  1. It is easy to retrieve.

  2. If more than one images are stored, we can easily retrieve image information.