Programs & Examples On #Cooliris


Change output format for MySQL command line results to CSV

mysql client can detect the output fd, if the fd is S_IFIFO(pipe) then don't output ASCII TABLES, if the fd is character device(S_IFCHR) then output ASCII TABLES.

you can use --table to force output the ASCII TABLES like:

$mysql -t -N -h127.0.0.1 -e "select id from sbtest1 limit 1" | cat
| 100024 |

-t, --table Output in table format.

java.lang.NoClassDefFoundError:failed resolution of :Lorg/apache/http/ProtocolVersion

If you are using or below and your app is targeting API level 28 (Android 9.0) or above, you must include the following declaration within the element of AndroidManifest.xml.

      android:required="false" />

This is handled for you if you are using and is not necessary if your app is targeting a lower API level.

Get Client Machine Name in PHP

In opposite to the most comments, I think it is possible to get the client's hostname (machine name) in plain PHP, but it's a little bit "dirty".

By requesting "NTLM" authorization via HTTP header...

if (!isset($headers['AUTHORIZATION']) || substr($headers['AUTHORIZATION'],0,4) !== 'NTLM'){
    header('HTTP/1.1 401 Unauthorized');
    header('WWW-Authenticate: NTLM');

You can force the client to send authorization credentials via NTLM format. The NTLM hash sent by the client to server contains, besides the login credtials, the clients machine name. This works cross-browser and PHP only.

$auth = $headers['AUTHORIZATION'];

if (substr($auth,0,5) == 'NTLM ') {
    $msg = base64_decode(substr($auth, 5));
    if (substr($msg, 0, 8) != "NTLMSSPx00")
            die('error header not recognised');

    if ($msg[8] == "x01") {
            $msg2 = "NTLMSSPx00x02"."x00x00x00x00".

            header('HTTP/1.1 401 Unauthorized');
            header('WWW-Authenticate: NTLM '.trim(base64_encode($msg2)));
    else if ($msg[8] == "x03") {
            function get_msg_str($msg, $start, $unicode = true) {
                    $len = (ord($msg[$start+1]) * 256) + ord($msg[$start]);
                    $off = (ord($msg[$start+5]) * 256) + ord($msg[$start+4]);
                    if ($unicode)
                            return str_replace("\0", '', substr($msg, $off, $len));
                            return substr($msg, $off, $len);
            $user = get_msg_str($msg, 36);
            $domain = get_msg_str($msg, 28);
            $workstation = get_msg_str($msg, 44);
            print "You are $user from $workstation.$domain";

And yes, it's not a plain and easy "read the machine name function", because the user is prompted with an dialog, but it's an example, that it is indeed possible (against the other statements here).

Full code can be found here:

How to access session variables from any class in ASP.NET?

In core this works differerently:

public class SomeOtherClass
    private readonly IHttpContextAccessor _httpContextAccessor;
    private ISession _session => _httpContextAccessor.HttpContext.Session;

    public SomeOtherClass(IHttpContextAccessor httpContextAccessor)
        _httpContextAccessor = httpContextAccessor;

    public void TestSet()
        _session.SetString("Test", "Ben Rules!");

    public void TestGet()
        var message = _session.GetString("Test");


How to run cron once, daily at 10pm

To run once, daily at 10PM you should do something like this:

0 22 * * *

enter image description here

Full size image:


Disable future dates in jQuery UI Datepicker

Date for the future 1 year can be done by

$('.date').datepicker({dateFormat: 'yy-mm-dd', minDate:(0), maxDate:(365)});

you can change the date format too by the parameter dateFormat

How to stop Python closing immediately when executed in Microsoft Windows

In Python 2.7 adding this to the end of my py file (if __name__ == '__main__':) works:

closeInput = raw_input("Press ENTER to exit")
print "Closing..."

Set up DNS based URL forwarding in Amazon Route53

I was running into the exact same problem that Saurav described, but I really needed to find a solution that did not require anything other than Route 53 and S3. I created a how-to guide for my blog detailing what I did.

Here is what I came up with.


Using only the tools available in Amazon S3 and Amazon Route 53, create a URL Redirect that automatically forwards to the AWS Console sign-in page aliased to "MyAccount", located at .

This guide will teach you set up URL forwarding to any URL, not just ones from Amazon. You will learn how to set up forwarding to specific folders (like "/console" in my example), and how to change the protocol of the redirect from HTTP to HTTPS (or vice versa).

Step One: Create Your S3 Bucket

Open the S3 Management Console and click "Create Bucket"

Open the S3 management console and click "Create Bucket".

Step Two: Name Your S3 Bucket

Name your S3 Bucket

  1. Choose a Bucket Name. This step is really important! You must name the bucket EXACTLY the same as the URL you want to set up for forwarding. For this guide, I'll use the name "".

  2. Select whatever region works best for you. If you don't know, keep the default.

  3. Don't worry about setting up logging. Just click the "Create" button when you're ready.

Step 3: Enable Static Website Hosting and Specify Routing Rules

Enable Static Website Hosting and Specify Routing Rules

  1. In the properties window, open the settings for "Static Website Hosting".
  2. Select the option to "Enable website hosting".
  3. Enter a value for the "Index Document". This object (document) will never be served by S3, and you never have to upload it. Just use any name you want.
  4. Open the settings for "Edit Redirection Rules".
  5. Paste the following XML snippet in it's entirety.


If you're curious about what the above XML is doing, visit the AWM Documentation for "Syntax for Specifying Routing Rules". A bonus technique (not covered here) is forwarding to specific pages at the destination host, for example Read about the <ReplaceKeyWith> element if you need this functionality.

Step 4: Make Note of Your Redirect Bucket's "Endpoint"

Make a note of your Redirect Bucket's Endpoint

Make note of the Static Website Hosting "endpoint" that Amazon automatically created for this bucket. You'll need this for later, so highlight the entire URL, then copy and paste it to notepad.

CAUTION! At this point you can actually click this link to check to see if your Redirection Rules were entered correctly, but be careful! Here's why...

Let's say you entered the wrong value inside the <Hostname> tags in your Redirection Rules. Maybe you accidentally typed, instead of If you click the link to test the Endpoint URL, AWS will happily redirect your browser to the wrong address!

After noticing your mistake, you will probably edit the <Hostname> in your Redirection Rules to fix the error. Unfortunately, when you try to click the link again, you'll most likely end up being redirected back to the wrong address! Even though you fixed the <Hostname> entry, your browser is caching the previous (incorrect!) entry. This happens because we're using an HTTP 301 (permanent) redirect, which browsers like Chrome and Firefox will cache by default.

If you copy and paste the Endpoint URL to a different browser (or clear the cache in your current one), you'll get another chance to see if your updated <Hostname> entry is finally the correct one.

To be safe, if you want to test your Endpoint URL and Redirect Rules, you should open a private browsing session, like "Incognito Mode" in Chrome. Copy, paste, and test the Endpoint URL in Incognito Mode and anything cached will go away once you close the session.

Step 5: Open the Route53 Management Console and Go To the Record Sets for Your Hosted Zone (Domain Name)

Open the Route 53 Management Console to Add Record Sets to your Hosted Zone

  1. Select the Hosted Zone (domain name) that you used when you created your bucket. Since I named my bucket "", I'm going to select the Hosted Zone.
  2. Click on the "Go to Record Sets" button.

Step 6: Click the "Create Record Set" Button

Click the Create Record Set button

Clicking "Create Record Set" will open up the Create Record Set window on the right side of the Route53 Management Console.

Step 7: Create a CNAME Record Set

Create a CNAME Record Set

  1. In the Name field, enter the hostname portion of the URL that you used when naming your S3 bucket. The "hostname portion" of the URL is everything to the LEFT of your Hosted Zone's name. I named my S3 bucket "", and my Hosted Zone is "", so the hostname portion I need to enter is "url-redirect-example".

  2. Select "CNAME - Canonical name" for the Type of this Record Set.

  3. For the Value, paste in the Endpoint URL of the S3 bucket we created back in Step 3.

  4. Click the "Create Record Set" button. Assuming there are no errors, you'll now be able to see a new CNAME record in your Hosted Zone's list of Record Sets.

Step 8: Test Your New URL Redirect

Open up a new browser tab and type in the URL that we just set up. For me, that's If everything worked right, you should be sent directly to an AWS sign-in page.

Because we used the alias as our redirect's destination URL, Amazon knows exactly which account we're trying to access, and takes us directly there. This can be very handy if you want to give a short, clean, branded AWS login link to employees or contractors.

All done! Your URL forwarding should take you to the AWS sign-in page.


I personally love the various AWS services, but if you've decided to migrate DNS management to Amazon Route 53, the lack of easy URL forwarding can be frustrating. I hope this guide helped make setting up URL forwarding for your Hosted Zones a bit easier.

If you'd like to learn more, please take a look at the following pages from the AWS Documentation site.


scipy.misc module has no attribute imread?

python -m pip install pillow

This worked for me.

What's the best way to detect a 'touch screen' device using JavaScript?

Right so there is a huge debate over detecting touch/non-touch devices. The number of window tablets and the size of tablets is increasing creating another set of headaches for us web developers.

I have used and tested blmstr's answer for a menu. The menu works like this: when the page loads the script detects if this is a touch or non touch device. Based on that the menu would work on hover (non-touch) or on click/tap (touch).

In most of the cases blmstr's scripts seemed to work just fine (specifically the 2018 one). BUT there was still that one device that would be detected as touch when it is not or vice versa.

For this reason I did a bit of digging and thanks to this article I replaced a few lines from blmstr's 4th script into this:

function is_touch_device4() {
    if ("ontouchstart" in window)
        return true;

    if (window.DocumentTouch && document instanceof DocumentTouch)
        return true;

    return window.matchMedia( "(pointer: coarse)" ).matches;

alert('Is touch device: '+is_touch_device4());
console.log('Is touch device: '+is_touch_device4());

Because of the lockdown have a limited supply of touch devices to test this one but so far the above works great.

I would appreceate if anyone with a desktop touch device (ex. surface tablet) can confirm if script works all right.

Now in terms of support the pointer: coarse media query seems to be supported. I kept the lines above since I had (for some reason) issues on mobile firefox but the lines above the media query do the trick.


invalid target release: 1.7

Other than setting JAVA_HOME environment variable, you got to make sure you are using the correct JDK in your Maven run configuration. Go to Run -> Run Configuration, select your Maven Build configuration, go to JRE tab and set the correct Runtime JRE.

Maven run configuration

how does int main() and void main() work

If you really want to understand ANSI C 89, I need to correct you in one thing; In ANSI C 89 the difference between the following functions:

int main()
int main(void)
int main(int argc, char* argv[])


int main()

  • a function that expects unknown number of arguments of unknown types. Returns an integer representing the application software status.

int main(void)

  • a function that expects no arguments. Returns an integer representing the application software status.

int main(int argc, char * argv[])

  • a function that expects argc number of arguments and argv[] arguments. Returns an integer representing the application software status.

About when using each of the functions

int main(void)

  • you need to use this function when your program needs no initial parameters to run/ load (parameters received from the OS - out of the program it self).

int main(int argc, char * argv[])

  • you need to use this function when your program needs initial parameters to load (parameters received from the OS - out of the program it self).

About void main()

In ANSI C 89, when using void main and compiling the project AS -ansi -pedantic (in Ubuntu, e.g) you will receive a warning indicating that your main function is of type void and not of type int, but you will be able to run the project. Most C developers tend to use int main() on all of its variants, though void main() will also compile.

How do I use a file grep comparison inside a bash if/else statement?

if takes a command and checks its return value. [ is just a command.

if grep -q ...

How can I get customer details from an order in WooCommerce?

And another example to get the customer details from the database:

$order = new WC_Order($order_id);
$order_detail['status']              = $order->get_status();
$order_detail['customer_first_name'] = get_post_meta($order_id, '_billing_first_name', true);
$order_detail['customer_last_name']  = get_post_meta($order_id, '_billing_last_name', true);
$order_detail['customer_email']      = get_post_meta($order_id, '_billing_email', true);
$order_detail['customer_company']    = get_post_meta($order_id, '_billing_company', true);
$order_detail['customer_address']    = get_post_meta($order_id, '_billing_address_1', true);
$order_detail['customer_city']       = get_post_meta($order_id, '_billing_city', true);
$order_detail['customer_state']      = get_post_meta($order_id, '_billing_state', true);
$order_detail['customer_postcode']   = get_post_meta($order_id, '_billing_postcode', true);

Bash scripting, multiple conditions in while loop

The correct options are (in increasing order of recommendation):

# Single POSIX test command with -o operator (not recommended anymore).
# Quotes strongly recommended to guard against empty or undefined variables.
while [ "$stats" -gt 300 -o "$stats" -eq 0 ]

# Two POSIX test commands joined in a list with ||.
# Quotes strongly recommended to guard against empty or undefined variables.
while [ "$stats" -gt 300 ] || [ "$stats" -eq 0 ]

# Two bash conditional expressions joined in a list with ||.
while [[ $stats -gt 300 ]] || [[ $stats -eq 0 ]]

# A single bash conditional expression with the || operator.
while [[ $stats -gt 300 || $stats -eq 0 ]]

# Two bash arithmetic expressions joined in a list with ||.
# $ optional, as a string can only be interpreted as a variable
while (( stats > 300 )) || (( stats == 0 ))

# And finally, a single bash arithmetic expression with the || operator.
# $ optional, as a string can only be interpreted as a variable
while (( stats > 300 || stats == 0 ))

Some notes:

  1. Quoting the parameter expansions inside [[ ... ]] and ((...)) is optional; if the variable is not set, -gt and -eq will assume a value of 0.

  2. Using $ is optional inside (( ... )), but using it can help avoid unintentional errors. If stats isn't set, then (( stats > 300 )) will assume stats == 0, but (( $stats > 300 )) will produce a syntax error.

How to remove leading zeros using C#

I just crafted this as I needed a good, simple way.

If it gets to the final digit, and if it is a zero, it will stay.

You could also use a foreach loop instead for super long strings.

I just replace each leading oldChar with the newChar.

This is great for a problem I just solved, after formatting an int into a string.

    /* Like this: */
    int counterMax = 1000;
    int counter = ...;
    string counterString = counter.ToString($"D{counterMax.ToString().Length}");
    counterString = RemoveLeadingChars('0', ' ', counterString);
    string fullCounter = $"({counterString}/{counterMax})";
    // = (   1/1000) ... ( 430/1000) ... (1000/1000)

    static string RemoveLeadingChars(char oldChar, char newChar, char[] chars)
        string result = "";
        bool stop = false;
        for (int i = 0; i < chars.Length; i++)
            if (i == (chars.Length - 1)) stop = true;
            if (!stop && chars[i] == oldChar) chars[i] = newChar;
            else stop = true;
            result += chars[i];
        return result;

    static string RemoveLeadingChars(char oldChar, char newChar, string text)
        return RemoveLeadingChars(oldChar, newChar, text.ToCharArray());

I always tend to make my functions suitable for my own library, so there are options.

href="tel:" and mobile numbers

The BlackBerry browser and Safari for iOS (iPhone/iPod/iPad) automatically detect phone numbers and email addresses and convert them to links. If you don’t want this feature, you should use the following meta tags.

For Safari:

<meta name="format-detection" content="telephone=no">

For BlackBerry:

<meta http-equiv="x-rim-auto-match" content="none">


How to change angular port from 4200 to any other

In angular.json:

"serve": {
          "builder": "@angular-devkit/build-angular:dev-server",
          "options": {
          "browserTarget": "projectname:build",
          "port": 5000

I am using angular-cli. This worked for me.

CSS transition fade on hover

I recommend you to use an unordered list for your image gallery.

You should use my code unless you want the image to gain instantly 50% opacity after you hover out. You will have a smoother transition.

#photos li {
    opacity: .5;
    transition: opacity .5s ease-out;
    -moz-transition: opacity .5s ease-out;
    -webkit-transition: opacity .5s ease-out;
    -o-transition: opacity .5s ease-out;

#photos li:hover {
    opacity: 1;

Using headers with the Python requests library's get method

This answer taught me that you can set headers for an entire session:

s = requests.Session()
s.auth = ('user', 'pass')
s.headers.update({'x-test': 'true'})

# both 'x-test' and 'x-test2' are sent
s.get('', headers={'x-test2': 'true'})

Bonus: Sessions also handle cookies.

drag drop files into standard html file input

What you could do, is display a file-input and overlay it with your transparent drop-area, being careful to use a name like file[1]. {Be sure to have the enctype="multipart/form-data" inside your FORM tag.}

Then have the drop-area handle the extra files by dynamically creating more file inputs for files 2..number_of_files, be sure to use the same base name, populating the value-attribute appropriately.

Lastly (front-end) submit the form.

All that's required to handle this method is to alter your procedure to handle an array of files.

<strong> vs. font-weight:bold & <em> vs. font-style:italic

The problem is an issue of semantic meaning (as BoltClock mentions) and visual rendering.

Originally HTML used <b> and <i> for these purposes, entirely stylistic commands, laid down in the semantic environment of the document markup. CSS is an attempt to separate out as far as possible the stylistic elements of the medium. Thus style information such as bold and italics should go in CSS.

<strong> and <em> were introduced to fill the semantic need for text to be marked as more important or stressed. They have default stylistic interpretations akin to bold and italic, but they are not bound to that fate.

How to add SHA-1 to android application

If you are using Google Play App Signing, you don't need to add your SHA-1 keys manually, just login into Firebase go into "project settings"->"integration" and press a button to link Google Play with firebase, SHA-1 will be added automatically.

not finding android sdk (Unity)

1- Just open

2- scroll down to the bottom of that page

3- download last version of tools for your OS (for example

4- Unzip it

5- Delete folder tools from previous Android Sdk folder

6- Copy new folder tools to Android SDK Folder like this image:

enter image description here

Send request to curl with post data sourced from a file

If you are using form data to upload file,in which a parameter name must be specified , you can use:

curl -X POST -i -F "parametername=@filename" -F "additional_parm=param2" host:port/xxx

Floating Div Over An Image

Actually just adding margin-bottom: -20px; to the tag class fixed it right up.

Being block elements, div's naturally have defined borders that they try not to violate. To get them to layer for images, which have no content beside the image because they have no closing tag, you just have to force them to do what they do not want to do, like violate their natural boundaries.

.container {
  border: 1px solid #DDDDDD;
  width: 200px;
  height: 200px;
.tag {
  float: left;
  position: relative;
  left: 0px;
  top: 0px;
  background-color: green;
  z-index: 1000;
  margin-bottom: -20px;

Another toue to take would be to create div's using an image as the background, and then place content where ever you like.

<div id="imgContainer" style="
         background-image: url("foo.jpg"); 
         background-repeat: no-repeat; 
         background-size: cover; 
         -webkit-background-size: cover; 
         -mox-background-size: cover; 
         -o-background-size: cover;">
  <div id="theTag">BLAH BLAH BLAH</div>

Twitter Bootstrap 3, vertically center content

Option 1 is to use display:table-cell. You need to unfloat the Bootstrap col-* using float:none..

.center {

Option 2 is display:flex to vertical align the row with flexbox: {
   display: flex;
   align-items: center;

Vertical centering is very different in Bootstrap 4. See this answer for Bootstrap 4

'node' is not recognized as an internal or external command

Everytime I install node.js it needs a reboot and then the path is recognized.

Call a stored procedure with another in Oracle

Sure, you just call it from within the SP, there's no special syntax.


   PROCEDURE some_sp
      some_other_sp('parm1', 10, 20.42);

If the procedure is in a different schema than the one the executing procedure is in, you need to prefix it with schema name.

   PROCEDURE some_sp
      other_schema.some_other_sp('parm1', 10, 20.42);

Better way to revert to a previous SVN revision of a file?

I recently had to revert to a particular revision to debug an older build and this worked like magic:

svn up -r 3340 (or what ever your desired revision number)

I had to resolve all conflicts using "tc" option as I did not care about local changes (checked in everything I cared about prior to reverting)

To get back to head revision was simple too:

svn up

Calling a javascript function recursively

Using Named Function Expressions:

You can give a function expression a name that is actually private and is only visible from inside of the function ifself:

var factorial = function myself (n) {
    if (n <= 1) {
        return 1;
    return n * myself(n-1);
typeof myself === 'undefined'

Here myself is visible only inside of the function itself.

You can use this private name to call the function recursively.

See 13. Function Definition of the ECMAScript 5 spec:

The Identifier in a FunctionExpression can be referenced from inside the FunctionExpression's FunctionBody to allow the function to call itself recursively. However, unlike in a FunctionDeclaration, the Identifier in a FunctionExpression cannot be referenced from and does not affect the scope enclosing the FunctionExpression.

Please note that Internet Explorer up to version 8 doesn't behave correctly as the name is actually visible in the enclosing variable environment, and it references a duplicate of the actual function (see patrick dw's comment below).

Using arguments.callee:

Alternatively you could use arguments.callee to refer to the current function:

var factorial = function (n) {
    if (n <= 1) {
        return 1;
    return n * arguments.callee(n-1);

The 5th edition of ECMAScript forbids use of arguments.callee() in strict mode, however:

(From MDN): In normal code arguments.callee refers to the enclosing function. This use case is weak: simply name the enclosing function! Moreover, arguments.callee substantially hinders optimizations like inlining functions, because it must be made possible to provide a reference to the un-inlined function if arguments.callee is accessed. arguments.callee for strict mode functions is a non-deletable property which throws when set or retrieved.

Creating an Arraylist of Objects

ArrayList<Matrices> list = new ArrayList<Matrices>();
list.add( new Matrices(1,1,10) );
list.add( new Matrices(1,2,20) );

Bind TextBox on Enter-key press

Answered here quite elegantly using attached behaviors, my preferred method for almost anything.

WPF how to make textbox lose focus after hitting enter

Linker error: "linker input file unused because linking not done", undefined reference to a function in that file

I think you are confused about how the compiler puts things together. When you use -c flag, i.e. no linking is done, the input is C++ code, and the output is object code. The .o files thus don't mix with -c, and compiler warns you about that. Symbols from object file are not moved to other object files like that.

All object files should be on the final linker invocation, which is not the case here, so linker (called via g++ front-end) complains about missing symbols.

Here's a small example (calling g++ explicitly for clarity):

PROG ?= myprog
OBJS = worker.o main.o

all: $(PROG)

        g++ -Wall -pedantic -ggdb -O2 -c -o $@ $<

$(PROG): $(OBJS)
        g++ -Wall -pedantic -ggdb -O2 -o $@ $(OBJS)

There's also makedepend utility that comes with X11 - helps a lot with source code dependencies. You might also want to look at the -M gcc option for building make rules.

How do I determine whether an array contains a particular value in Java?

Actually, if you use HashSet<String> as Tom Hawtin proposed you don't need to worry about sorting, and your speed is the same as with binary search on a presorted array, probably even faster.

It all depends on how your code is set up, obviously, but from where I stand, the order would be:

On an unsorted array:

  1. HashSet
  2. asList
  3. sort & binary

On a sorted array:

  1. HashSet
  2. Binary
  3. asList

So either way, HashSet for the win.

ClassNotFoundException: org.slf4j.LoggerFactory

I had the same on Android. This is how i fixed it:

including ONLY the file:


in my libs/ folder

Having any additional slf4j* file, caused the NoClassDefFoundError.

Obviously, the rest of the libs can be there (android-support-v4, etc)

Versions: Eclipse Kepler 2013 06 14 - 02 29 ADT 22.3 Android SDK: 4.4.2

Hope someone saves the time i wasted thanks to this!

Cut Java String at a number of character

Use substring

String strOut = "abcdefghijklmnopqrtuvwxyz"
String result = strOut.substring(0, 8) + "...";// count start in 0 and 8 is excluded

Note: substring(int first, int second) takes two parameters. The first is inclusive and the second is exclusive.

Peak-finding algorithm for Python/SciPy

There are standard statistical functions and methods for finding outliers to data, which is probably what you need in the first case. Using derivatives would solve your second. I'm not sure for a method which solves both continuous functions and sampled data, however.

Check if input value is empty and display an alert

Also you can try this, if you want to focus on same text after error.

If you wants to show this error message in a paragraph then you can use this one:

 $(document).ready(function () {
    $("#submit").click(function () {
        if($('#selBooks').val() === '') {
            $("#Paragraph_id").text("Please select a book and then proceed.").show();
            return false;

How can I get just the first row in a result set AFTER ordering?

In 12c, here's the new way:

select bla
  from bla
 where bla
 order by finaldate desc
 fetch first 1 rows only; 

How nice is that!

Android emulator doesn't take keyboard input - SDK tools rev 20

I have used an emulator for API Level 23, which does not take keyboard input for installed apk. So I have created new emulator for API Level 29, and then it works. Following is the step to install new emulator.

  1. Open "Android Virtual Device Manager"
  2. Create new Virtual Device.
  3. When you select a system image, please choose and download the last version(API Level29) on "Virtual Device Configuration" window

How do I check if a C++ string is an int?

template <typename T>
const T to(const string& sval)
        T val;
        stringstream ss;
        ss << sval;
        ss >> val;
                throw runtime_error((string)typeid(T).name() + " type wanted: " + sval);
        return val;

And then you can use it like that:

double d = to<double>("4.3");


int i = to<int>("4123");

Open Windows Explorer and select a file

Check out this snippet:

Private Sub openDialog()
    Dim fd As Office.FileDialog

    Set fd = Application.FileDialog(msoFileDialogFilePicker)

   With fd

      .AllowMultiSelect = False

      ' Set the title of the dialog box.
      .Title = "Please select the file."

      ' Clear out the current filters, and add our own.
      .Filters.Add "Excel 2003", "*.xls"
      .Filters.Add "All Files", "*.*"

      ' Show the dialog box. If the .Show method returns True, the
      ' user picked at least one file. If the .Show method returns
      ' False, the user clicked Cancel.
      If .Show = True Then
        txtFileName = .SelectedItems(1) 'replace txtFileName with your textbox

      End If
   End With
End Sub

I think this is what you are asking for.

When to use @QueryParam vs @PathParam

  1. @QueryParam can be conveniently used with the Default Value annotation so that you can avoid a null pointer exception if no query parameter is passed.

When you want to parse query parameters from a GET request, you can simply define respective parameter to the method that will handle the GET request and annotate them with @QueryParam annotation

  1. @PathParam extracts the URI values and matches to @Path. And hence gets the input parameter. 2.1 @PathParam can be more than one and is set to methods arguments

    public class Abc {
        public String add(@PathParam("p0") Integer param1, @PathParam("p1")  Integer param2 )
            return String.valueOf(param1+param2);

In the above example,
p0 matches param1 and p1 matches param2. So for the URI
we get the result 10.

In REST Service, JAX-RS provides @QueryParam and @FormParam both for accepting data from HTTP request. An HTTP form can be submitted by different methods like GET and POST.

@QueryParam : Accepts GET request and reads data from query string.

@FormParam: Accepts POST request and fetches data from HTML form or any request of the media

Calculating text width

Neither Rune's nor Brain's was working for me in case when the element that was holding the text had fixed width. I did something similar to Okamera. It uses less selectors.

EDIT: It won't probably work for elements that uses relative font-size, as following code inserts htmlCalc element into body thus looses the information about parents relation.

$.fn.textWidth = function() {
    var htmlCalc = $('<span>' + this.html() + '</span>');
    htmlCalc.css('font-size', this.css('font-size'))
    var width = htmlCalc.width();
    return width;

Python style - line continuation with strings?

Just pointing out that it is use of parentheses that invokes auto-concatenation. That's fine if you happen to already be using them in the statement. Otherwise, I would just use '\' rather than inserting parentheses (which is what most IDEs do for you automatically). The indent should align the string continuation so it is PEP8 compliant. E.g.:

my_string = "The quick brown dog " \
            "jumped over the lazy fox"

Check if certain value is contained in a dataframe column in pandas

I think you need str.contains, if you need rows where values of column date contains string 07311954:

print df[df['date'].astype(str).str.contains('07311954')]

Or if type of date column is string:

print df[df['date'].str.contains('07311954')]

If you want check last 4 digits for string 1954 in column date:

print df[df['date'].astype(str).str[-4:].str.contains('1954')]


print df['date']
0    8152007
1    9262007
2    7311954
3    2252011
4    2012011
5    2012011
6    2222011
7    2282011
Name: date, dtype: int64

print df['date'].astype(str).str[-4:].str.contains('1954')
0    False
1    False
2     True
3    False
4    False
5    False
6    False
7    False
Name: date, dtype: bool

print df[df['date'].astype(str).str[-4:].str.contains('1954')]
     cmte_id trans_typ entity_typ state  employer  occupation     date  \
2  C00119040       24K        CCM    MD       NaN         NaN  7311954   

   amount     fec_id    cand_id  
2    1000  C00140715  H2MD05155  

How to perform grep operation on all files in a directory?

Use find. Seriously, it is the best way because then you can really see what files it's operating on:

find . -name "*.sql" -exec grep -H "slow" {} \;

Note, the -H is mac-specific, it shows the filename in the results.

How can I change the Y-axis figures into percentages in a barplot?


+ scale_y_continuous(labels = scales::percent)

Or, to specify formatting parameters for the percent:

+ scale_y_continuous(labels = scales::percent_format(accuracy = 1))

(the command labels = percent is obsolete since version 2.2.1 of ggplot2)

How to activate JMX on my JVM for access with jconsole?

Note, Java 6 in the latest incarnation allows for jconsole to attach itself to a running process even after it has been started without JMX incantations.

If that is available to you, also consider jvisualvm as it provides a wealth of information on running processes, including a profiler.

Fade In on Scroll Down, Fade Out on Scroll Up - based on element position in window

I tweaked your code a bit and made it more robust. In terms of progressive enhancement it's probaly better to have all the fade-in-out logic in JavaScript. In the example of myfunksyde any user without JavaScript sees nothing because of the opacity: 0;.

    $(window).on("load",function() {
    function fade() {
        var animation_height = $(window).innerHeight() * 0.25;
        var ratio = Math.round( (1 / animation_height) * 10000 ) / 10000;

        $('.fade').each(function() {

            var objectTop = $(this).offset().top;
            var windowBottom = $(window).scrollTop() + $(window).innerHeight();

            if ( objectTop < windowBottom ) {
                if ( objectTop < windowBottom - animation_height ) {
                    $(this).html( 'fully visible' );
                    $(this).css( {
                        transition: 'opacity 0.1s linear',
                        opacity: 1
                    } );

                } else {
                    $(this).html( 'fading in/out' );
                    $(this).css( {
                        transition: 'opacity 0.25s linear',
                        opacity: (windowBottom - objectTop) * ratio
                    } );
            } else {
                $(this).html( 'not visible' );
                $(this).css( 'opacity', 0 );
    $('.fade').css( 'opacity', 0 );
    $(window).scroll(function() {fade();});

See it here:

Cheers, Martin

Linux command-line call not returning what it should from os.system?

What gets returned is the return value of executing this command. What you see in while executing it directly is the output of the command in stdout. That 0 is returned means, there was no error in execution.

Use popen etc for capturing the output .

Some thing along this line:

import subprocess as sub
p = sub.Popen(['your command', 'arg1', 'arg2', ...],stdout=sub.PIPE,stderr=sub.PIPE)
output, errors = p.communicate()
print output


import os
p = os.popen('command',"r")
while 1:
    line = p.readline()
    if not line: break
    print line

ON SO : Popen and python

Generate a range of dates using SQL

Date range between 12/31/1996 and 12/31/2020

SELECT dt, to_char(dt, 'MM/DD/YYYY') as date_name, 
  EXTRACT(year from dt) as year, 
  EXTRACT(year from fiscal_dt) as fiscal_year,
  initcap(to_char(dt, 'MON')) as month,
  to_char(dt, 'YYYY')        || ' ' || initcap(to_char(dt, 'MON')) as year_month,
  to_char(fiscal_dt, 'YYYY') || ' ' || initcap(to_char(dt, 'MON')) as fiscal_year_month,
  EXTRACT(year from dt)*100        + EXTRACT(month from dt) as year_month_id,
  EXTRACT(year from fiscal_dt)*100 + EXTRACT(month from fiscal_dt) as fiscal_year_month_id,
  to_char(dt, 'YYYY')        || ' Q' || to_char(dt, 'Q') as quarter,
  to_char(fiscal_dt, 'YYYY') || ' Q' || to_char(fiscal_dt, 'Q') as fiscal_quarter
  --, EXTRACT(day from dt) as day_of_month, to_char(dt, 'YYYY-WW') as week_of_year, to_char(dt, 'D') as day_of_week
  FROM (
    SELECT dt, add_months(dt, 6) as fiscal_dt --starts July 1st
    FROM (
      SELECT TO_DATE('12/31/1996', 'mm/dd/yyyy') + ROWNUM as dt 
      FROM DUAL CONNECT BY ROWNUM < 366 * 30 --30 years
    WHERE dt <= TO_DATE('12/31/2020', 'mm/dd/yyyy')

How to count the number of columns in a table using SQL?

Maybe something like this:

SELECT count(*) FROM user_tab_columns WHERE table_name = 'FOO'

this will count number of columns in a the table FOO

You can also just

select count(*) from all_tab_columns where owner='BAR' and table_name='FOO';

where the owner is schema and note that Table Names are upper case

How to Validate a DateTime in C#?

One liner:

if (DateTime.TryParse(value, out _)) {//dostuff}

Nested ifelse statement

Try something like the following:

# some sample data
idnat <- sample(c("french","foreigner"),100,TRUE)
idbp <- rep(NA,100)
idbp[idnat=="french"] <- sample(c("mainland","overseas","colony"),sum(idnat=="french"),TRUE)

# recoding
out <- ifelse(idnat=="french" & !idbp %in% c("overseas","colony"), "mainland",
              ifelse(idbp %in% c("overseas","colony"),"overseas",
cbind(idnat,idbp,out) # check result

Your confusion comes from how SAS and R handle if-else constructions. In R, if and else are not vectorized, meaning they check whether a single condition is true (i.e., if("french"=="french") works) and cannot handle multiple logicals (i.e., if(c("french","foreigner")=="french") doesn't work) and R gives you the warning you're receiving.

By contrast, ifelse is vectorized, so it can take your vectors (aka input variables) and test the logical condition on each of their elements, like you're used to in SAS. An alternative way to wrap your head around this would be to build a loop using if and else statements (as you've started to do here) but the vectorized ifelse approach will be more efficient and involve generally less code.

setBackground vs setBackgroundDrawable (Android)

It's deprecated but it still works so you could just use it. But if you want to be completly correct, just for the completeness of it... You'd do something like following:

int sdk = android.os.Build.VERSION.SDK_INT;
if(sdk < android.os.Build.VERSION_CODES.JELLY_BEAN) {
} else {

For this to work you need to set buildTarget api 16 and min build to 7 or something similar.

Java GUI frameworks. What to choose? Swing, SWT, AWT, SwingX, JGoodies, JavaFX, Apache Pivot?

I would go with Swing. For layout I would use JGoodies form layout. Its worth studying the white paper on the Form Layout here -

Also if you are going to start developing a huge desktop application, you will definitely need a framework. Others have pointed out the netbeans framework. I didnt like it much so wrote a new one that we now use in my company. I have put it onto sourceforge, but didnt find the time to document it much. Here's the link to browse the code:

The showcase should show you how to do a simple logon actually..

Let me know if you have any questions on it I could help.

Posting raw image data as multipart/form-data in curl

As of PHP 5.6 @$filePath will not work in CURLOPT_POSTFIELDS without CURLOPT_SAFE_UPLOAD being set and it is completely removed in PHP 7. You will need to use a CurlFile object, RFC here.

$fields = [
    'name' => new \CurlFile($filePath, 'image/png', 'filename.png')
curl_setopt($resource, CURLOPT_POSTFIELDS, $fields);

Lua string to int

tonumber (e [, base])

tonumber takes two arguments, first is string which is converted to number and second is base of e.

Return value tonumber is in base 10.

If no base is provided it converts number to base 10.

> a = '101'
> tonumber(a)

If base is provided, it converts it to the given base.

> a = '101'
> tonumber(a, 2)
> tonumber(a, 8)
> tonumber(a, 10)
> tonumber(a, 16)

If e contains invalid character then it returns nil.

> --[[ Failed because base 2 numbers consist (0 and 1) --]]
> a = '112'
> tonumber(a, 2)
> --[[ similar to above one, this failed because --]]
> --[[ base 8 consist (0 - 7) --]]
> --[[ base 10 consist (0 - 9) --]]
> a = 'AB'
> tonumber(a, 8)
> tonumber(a, 10)
> tonumber(a, 16)

I answered considering Lua5.3

Remove non-ASCII characters from CSV

I appreciate the tips I found on this site.

But, on my Windows 10, I had to use double quotes for this to work ...

sed -i "s/[\d128-\d255]//g" FILENAME

Noticed these things ...

  1. For FILENAME the entire path\name needs to be quoted This didn't work -- %TEMP%\"FILENAME" This did -- %TEMP%\FILENAME"

  2. sed leaves behind temp files in the current directory, named sed*

How can I fix WebStorm warning "Unresolved function or method" for "require" (Firefox Add-on SDK)

Working with Intellj 2016, Angular2, and Typescript... the only thing that worked for me was to get the Typescript Definitions for NodeJS

Get node.d.ts from DefinitelyTyped on GitHub

Or just run:

npm install @types/node --save-dev

Then in tsconfig.json, include

"types": [

Excel VBA - Range.Copy transpose paste

Here's an efficient option that doesn't use the clipboard.

Sub transposeAndPasteRow(rowToCopy As Range, pasteTarget As Range)
    pasteTarget.Resize(rowToCopy.Columns.Count) = Application.WorksheetFunction.Transpose(rowToCopy.Value)
End Sub

Use it like this.

Sub test()
    Call transposeAndPasteRow(Worksheets("Sheet1").Range("A1:A5"), Worksheets("Sheet2").Range("A1"))
End Sub

NVIDIA NVML Driver/library version mismatch

First I installed the Nvidia driver.

Next I installed cuda.

Ater that I got the "Driver/library version mismatch" ERROR but I could see the cuda version so I purged the Nvidia driver and reinstall it.

Then it worked correctly.

How to get autocomplete in jupyter notebook without using tab?

I would suggest hinterland extension.

In other answers I couldn't find the method for how to install it from pip, so this is how you install it.

First, install jupyter contrib nbextensions by running

pip install jupyter_contrib_nbextensions

Next install js and css file for jupyter by running

jupyter contrib nbextension install --user

and at the end run,

jupyter nbextension enable hinterland/hinterland

The output of last command will be

Enabling notebook extension hinterland/hinterland...
      - Validating: OK

Limit on the WHERE col IN (...) condition

You did not specify the database engine in question; in Oracle, an option is to use tuples like this:

SELECT * FROM table WHERE (Col, 1) IN ((123,1),(123,1),(222,1),....)

This ugly hack only works in Oracle SQL, see

However, a much better option is to use stored procedures and pass the values as an array.

C#, Looping through dataset and show each record from a dataset column

I believe you intended it more this way:

foreach (DataTable table in ds.Tables)
    foreach (DataRow dr in table.Rows)
        DateTime TaskStart = DateTime.Parse(dr["TaskStart"].ToString());
        rpt.SetParameterValue("TaskStartDate", TaskStart);

You always accessed your first row in your dataset.

How to add background-image using ngStyle (angular2)?

I think you could try this:

<div [ngStyle]="{'background-image': 'url(' + photo + ')'}"></div>

From reading your ngStyle expression, I guess that you missed some "'"...

SyntaxError: non-default argument follows default argument

Let me clarify two points here :

  • Firstly non-default argument should not follow the default argument, it means you can't define (a = 'b',c) in function. The correct order of defining parameter in function are :
  • positional parameter or non-default parameter i.e (a,b,c)
  • keyword parameter or default parameter i.e (a = 'b',r= 'j')
  • keyword-only parameter i.e (*args)
  • var-keyword parameter i.e (**kwargs)

def example(a, b, c=None, r="w" , d=[], *ae, **ab):

(a,b) are positional parameter

(c=none) is optional parameter

(r="w") is keyword parameter

(d=[]) is list parameter

(*ae) is keyword-only

(*ab) is var-keyword parameter

so first re-arrange your parameters

  • now the second thing is you have to define len1 when you are doing hgt=len1 the len1 argument is not defined when default values are saved, Python computes and saves default values when you define the function len1 is not defined, does not exist when this happens (it exists only when the function is executed)

so second remove this "len1 = hgt" it's not allowed in python.

keep in mind the difference between argument and parameters.

Entity Framework code-first: migration fails with update-database, forces unneccessary(?) add-migration

In answer to your general question of

So I am curious: What did I do to disorientate migrations? And what can I do to get it working with just one initial migration?

I've just had the same error message as you after I merged several branches and the migrations got confused about the current state of the database. Worst of all, this was only happening on the client's server, not on our development systems.

In trying to work out what was happening there, I came across this superb Microsoft guide:

Microsoft's guide to Code First Migrations in Team Environments

Whilst that guide was written to explain migrations in teams, it also gives the best explanation I've found of how the migrations work internally, which may well lead to an explanation for the behaviour your seeing. It's very worth putting an hour aside to read all of that for anyone who works with EF6 or below.

For anyone brought to this question by that error message after merging migrations, the trick of generating a blank migration with the current state of the database solved things for me, but do be very sure to have read the whole guide to know if that solution is appropriate in your case.

SQL select max(date) and corresponding value

You can use a subquery. The subquery will get the Max(CompletedDate). You then take this value and join on your table again to retrieve the note associate with that date:

select ET1.TrainingID,
from HR_EmployeeTrainings ET1
inner join
  select Max(CompletedDate) CompletedDate, TrainingID
  from HR_EmployeeTrainings
  --where AvantiRecID IS NULL OR AvantiRecID = @avantiRecID
  group by TrainingID
) ET2
  on ET1.TrainingID = ET2.TrainingID
  and ET1.CompletedDate = ET2.CompletedDate
where ET1.AvantiRecID IS NULL OR ET1.AvantiRecID = @avantiRecID

How to make nginx to listen to server_name:port

The server_namedocs directive is used to identify virtual hosts, they're not used to set the binding.

netstat tells you that nginx listens on which means that it will accept connections from any IP.

If you want to change the IP nginx binds on, you have to change the listendocs rule.
So, if you want to set nginx to bind to localhost, you'd change that to:


In this way, requests that are not coming from localhost are discarded (they don't even hit nginx).

Docker expose all ports or range of ports from 7000 to 8000

Since Docker 1.5 you can now expose a range of ports to other linked containers using:

The Dockerfile EXPOSE command:

EXPOSE 7000-8000

or The Docker run command:

docker run --expose=7000-8000

Or instead you can publish a range of ports to the host machine via Docker run command:

docker run -p 7000-8000:7000-8000

Android - drawable with rounded corners at the top only

Create roung_top_corners.xml on drawable and copy the below code

<shape xmlns:android="" android:shape="rectangle" >
    android:type="linear" />

What is the LDF file in SQL Server?

The LDF is the transaction log. It keeps a record of everything done to the database for rollback purposes.

You do not want to delete, but you can shrink it with the dbcc shrinkfile command. You can also right-click on the database in SQL Server Management Studio and go to Tasks > Shrink.

Determine whether an array contains a value

Since ECMAScript6, one can use Set:

var myArray = ['A', 'B', 'C'];
var mySet = new Set(myArray);
var hasB = mySet.has('B'); // true
var hasZ = mySet.has('Z'); // false

What is web.xml file and what are all things can I do with it?

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="" xmlns="" xmlns:web="" xsi:schemaLocation="" version="3.0">

How can I force a hard reload in Chrome for Android

How to reset all data for a given URL / Website on Chrome Mobile for android:

1 - Open the Chrome menu, and tap on the "i (info)" icon


2 - tap "Site settings"


3 - Tap the trashcan icon


That's it, even the most deeply ensconsed service worker for that URL will now die.

Redirect all output to file in Bash

You can use exec command to redirect all stdout/stderr output of any commands later.

sample script:

exec 2> your_file2 > your_file1
your other commands.....


Try this

UPDATE `table` SET `uid` = CASE
    WHEN id = 1 THEN 2952
    WHEN id = 2 THEN 4925
    WHEN id = 3 THEN 1592
    ELSE `uid`
WHERE id  in (1,2,3)

How do I add a delay in a JavaScript loop?

This will work

for (var i = 0; i < 10; i++) {
  (function(i) {
    setTimeout(function() { console.log(i); }, 100 * i);

Try this fiddle:

Posting JSON Data to ASP.NET MVC

If you've got ther JSON data coming in as a string (e.g. '[{"id":1,"name":"Charles"},{"id":8,"name":"John"},{"id":13,"name":"Sally"}]')

Then I'd use and use Linq to JSON to get the values out...

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

public partial class _Default : System.Web.UI.Page
protected void Page_Load(object sender, EventArgs e)

    if (Request["items"] != null)
        var items = Request["items"].ToString(); // Get the JSON string
        JArray o = JArray.Parse(items); // It is an array so parse into a JArray
        var a = o.SelectToken("[0].name").ToString(); // Get the name value of the 1st object in the array
        // a == "Charles"

How can I store JavaScript variable output into a PHP variable?

You can solve this problem by using AJAX. You don't need to load JQuery for AJAX but it has a better error and success handling than native JS.

I would do it like so:

1) add an click eventlistener to all my anchors on the page. 2) on click, you can setup an ajax-request to your php, in the POST-DATA you set the anchor id or the text-value 3) the php gets the value and you can setup a request to your database. Then you return the value which you need and echo it to the ajax-request. 4) your success function of the ajax-request is doing some stuff

For more information about ajax-requests look back here:

-> Ajax-Request NATIVE

A simple JQuery examle:

  $.ajax({url: "demo_test.txt", success: function(result){

jQuery not working with IE 11

Place this meta tag after head tag

<meta http-equiv="x-ua-compatible" content="IE=edge">

How to force cp to overwrite without confirmation

Another way to call the command without the alias is to use the command builtin in bash.

command cp -rf /zzz/zzz/*

How can I remove or replace SVG content?

If you want to get rid of all children,


will remove all content associated with the svg.

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

I copied remote origin url from another .git/config file, doing so my new .git/config file was missing following line in [remote "origin"] section

fetch = +refs/heads/*:refs/remotes/origin/*

Adding above line fixed error: pathspec 'master' did not match any file(s) known to git.

Handling of non breaking space: <p>&nbsp;</p> vs. <p> </p>

How about a workaround? In my case I took the value of the textarea in a jQuery variable, and changed all "<p>&nbsp" to <p class="clear"> and clear class to have certain height and margin, as the following example:


var val = $('textarea').val();
val = val.replace(/<p>&nbsp/g, '<p class="clear">');

the val is then saved to the database with the new val.


p.clear{height: 2px; margin-bottom: 3px;}

You can adjust the height & margin as you wish. And since 'p' is a display: block element. it should give you the expected output.

Hope that helps!

Run react-native application on iOS device directly from command line?

First install the required library globally on your computer:

npm install -g ios-deploy

Go to your settings on your iPhone to find the name of the device.

Then provide that below like:

react-native run-ios --device "______\'s iPhone"

Sometimes this will fail and output a message like this:

Found Xcode project ________.xcodeproj
Could not find device with the name: "_______'s iPhone".
Choose one of the following:
______’s iPhone Udid: _________

That udid is used like this:

react-native run-ios --udid 0412e2c230a14e23451699

Optionally you may use:

react-native run-ios --udid 0412e2c230a14e23451699 -- configuration Release

How to check if a String contains any of some strings

If you are looking for single characters, you can use String.IndexOfAny().

If you want arbitrary strings, then I'm not aware of a .NET method to achieve that "directly", although a regular expression would work.

Sorting A ListView By Column

I sort using column name to set any sorting specifics that may need to be handled based on data type stored in the column and or if the column has already been sorted on(asc/desc). Here's a snippet from my ColumnClick event handler.

private void listView_ColumnClick(object sender, ColumnClickEventArgs e)
        ListViewItemComparer sorter = GetListViewSorter(e.Column);

        listView.ListViewItemSorter = sorter;

    private ListViewItemComparer GetListViewSorter(int columnIndex)
        ListViewItemComparer sorter = (ListViewItemComparer)listView.ListViewItemSorter;
        if (sorter == null)
            sorter = new ListViewItemComparer();

        sorter.ColumnIndex = columnIndex;

        string columnName = packagedEstimateListView.Columns[columnIndex].Name;
        switch (columnName)
            case ApplicationModel.DisplayColumns.DateCreated:
            case ApplicationModel.DisplayColumns.DateUpdated:
                sorter.ColumnType = ColumnDataType.DateTime;
            case ApplicationModel.DisplayColumns.NetTotal:
            case ApplicationModel.DisplayColumns.GrossTotal:
                sorter.ColumnType = ColumnDataType.Decimal;
                sorter.ColumnType = ColumnDataType.String;

        if (sorter.SortDirection == SortOrder.Ascending)
            sorter.SortDirection = SortOrder.Descending;
            sorter.SortDirection = SortOrder.Ascending;

        return sorter;

Below is my ListViewItemComparer

public class ListViewItemComparer : IComparer
    private int _columnIndex;
    public int ColumnIndex
            return _columnIndex;
            _columnIndex = value;

    private SortOrder _sortDirection;
    public SortOrder SortDirection
            return _sortDirection;
            _sortDirection = value;

    private ColumnDataType _columnType;
    public ColumnDataType ColumnType
            return _columnType;
            _columnType = value;

    public ListViewItemComparer()
        _sortDirection = SortOrder.None;

    public int Compare(object x, object y)
        ListViewItem lviX = x as ListViewItem;
        ListViewItem lviY = y as ListViewItem;

        int result;

        if (lviX == null && lviY == null)
            result = 0;
        else if (lviX == null)
            result = -1;

        else if (lviY == null)
            result = 1;

        switch (ColumnType)
            case ColumnDataType.DateTime:
                DateTime xDt = DataParseUtility.ParseDate(lviX.SubItems[ColumnIndex].Text);
                DateTime yDt = DataParseUtility.ParseDate(lviY.SubItems[ColumnIndex].Text);
                result = DateTime.Compare(xDt, yDt);

            case ColumnDataType.Decimal:
                Decimal xD = DataParseUtility.ParseDecimal(lviX.SubItems[ColumnIndex].Text.Replace("$", string.Empty).Replace(",", string.Empty));
                Decimal yD = DataParseUtility.ParseDecimal(lviY.SubItems[ColumnIndex].Text.Replace("$", string.Empty).Replace(",", string.Empty));
                result = Decimal.Compare(xD, yD);
            case ColumnDataType.Short:
                short xShort = DataParseUtility.ParseShort(lviX.SubItems[ColumnIndex].Text);
                short yShort = DataParseUtility.ParseShort(lviY.SubItems[ColumnIndex].Text);
                result = xShort.CompareTo(yShort);
            case ColumnDataType.Int:
                int xInt = DataParseUtility.ParseInt(lviX.SubItems[ColumnIndex].Text);
                int yInt = DataParseUtility.ParseInt(lviY.SubItems[ColumnIndex].Text);
                return xInt.CompareTo(yInt);
            case ColumnDataType.Long:
                long xLong = DataParseUtility.ParseLong(lviX.SubItems[ColumnIndex].Text);
                long yLong = DataParseUtility.ParseLong(lviY.SubItems[ColumnIndex].Text);
                return xLong.CompareTo(yLong);

                result = string.Compare(


        if (SortDirection == SortOrder.Descending)
            return -result;
            return result;

Changing the action of a form with JavaScript/jQuery

just to add a detail to what Tamlyn wrote, instead of
$('form').get(0).setAttribute('action', 'baz'); //this works

$('form')[0].setAttribute('action', 'baz');
works equally well

Build Error - missing required architecture i386 in file

I'd just experienced something slightly different, because I work on my own library (WM_GSRecognizerLib), but the error is the same.

What'd happen: due to some updates, the path targeting the lib to include (.a) was from the "Debug-iphoneos" folder (where it is generated). Compiling for Generic iOS Devices worked fine, but not for simulator, complaining for the missing i386 architecture.

What I did for this issue, is to also include the binaries from the "Debug-iphonesimulator" folder.

It can help for this topic, because the explanation is here: devices require binaries for arm64/armv7/armv7s, while simulator does need i386.

read string from .resx file in C#

This example is from the MSDN page on ResourceManager.GetString():

// Create a resource manager to retrieve resources.
ResourceManager rm = new ResourceManager("items", Assembly.GetExecutingAssembly());

// Retrieve the value of the string resource named "welcome".
// The resource manager will retrieve the value of the  
// localized resource using the caller's current culture setting.
String str = rm.GetString("welcome");

What is stability in sorting algorithms and why is it important?

Sorting stability means that records with the same key retain their relative order before and after the sort.

So stability matters if, and only if, the problem you're solving requires retention of that relative order.

If you don't need stability, you can use a fast, memory-sipping algorithm from a library, like heapsort or quicksort, and forget about it.

If you need stability, it's more complicated. Stable algorithms have higher big-O CPU and/or memory usage than unstable algorithms. So when you have a large data set, you have to pick between beating up the CPU or the memory. If you're constrained on both CPU and memory, you have a problem. A good compromise stable algorithm is a binary tree sort; the Wikipedia article has a pathetically easy C++ implementation based on the STL.

You can make an unstable algorithm into a stable one by adding the original record number as the last-place key for each record.

Can anyone explain python's relative imports?

You are importing from package "sub". is not itself in a package even if there is a present.

You would need to start your program from one directory over




import pkg.sub.relative

Now pkg is the top level package and your relative import should work.

If you want to stick with your current layout you can just use import parent. Because you use to launch your interpreter, the directory where is located is in your python path. lives there as a separate module.

You can also safely delete the top level, if you don't import anything into a script further up the directory tree.

It says that TypeError: document.getElementById(...) is null

All these results in null:


You need to do a null check in updateHTML like this:

function updateHTML(elmId, value) {
  var elem = document.getElementById(elmId);
  if(typeof elem !== 'undefined' && elem !== null) {
    elem.innerHTML = value;

is there something like isset of php in javascript/jQuery?

Not naturally, no... However, a googling of the thing gave this:

How to get 0-padded binary representation of an integer in java?

You can use lib It accept a number and return bynary string, padded and/or grouped.

String s = new BitSequence(2, 16).toBynaryString(ALIGN.RIGHT, GROUP.CONTINOUSLY));  

another examples:

[10, -20, 30]->00001010 11101100 00011110
sh=10->00 0000 0000 1010
l=10->00000001 010
i=-10->bc->11111111 11111111 11111111 11110110


Since you want to pivot multiple columns of data, I would first suggest unpivoting the result, score and grade columns so you don't have multiple columns but you will have multiple rows.

Depending on your version of SQL Server you can use the UNPIVOT function or CROSS APPLY. The syntax to unpivot the data will be similar to:

select ratio, col, value
cross apply
  select 'result', cast(result as varchar(10)) union all
  select 'score', cast(score as varchar(10)) union all
  select 'grade', grade
) c(col, value)

See SQL Fiddle with Demo. Once the data has been unpivoted, then you can apply the PIVOT function:

select ratio = col,
  [current ratio], [gearing ratio], [performance ratio], total
  select ratio, col, value
  cross apply
    select 'result', cast(result as varchar(10)) union all
    select 'score', cast(score as varchar(10)) union all
    select 'grade', grade
  ) c(col, value)
) d
  for ratio in ([current ratio], [gearing ratio], [performance ratio], total)
) piv;

See SQL Fiddle with Demo. This will give you the result:

|  grade |          Good |          Good |      Satisfactory |      Good |
| result |       1.29400 |       0.33840 |           0.04270 |    (null) |
|  score |      60.00000 |      70.00000 |          50.00000 | 180.00000 |

How to fix getImageData() error The canvas has been tainted by cross-origin data?

As matt burns says in his answer, you may need to enable CORS on the server where the problem images are hosted.

If the server is Apache, this can be done by adding the following snippet (from here) to either your VirtualHost config or an .htaccess file:

<IfModule mod_setenvif.c>
    <IfModule mod_headers.c>
        <FilesMatch "\.(cur|gif|ico|jpe?g|png|svgz?|webp)$">
            SetEnvIf Origin ":" IS_CORS
            Header set Access-Control-Allow-Origin "*" env=IS_CORS

...if adding it to a VirtualHost, you'll probably need to reload Apache's config too (eg. sudo service apache2 reload if Apache's running on a Linux server)

Right query to get the current number of connections in a PostgreSQL DB

Aggregation of all postgres sessions per their status (how many are idle, how many doing something...)

select state, count(*) from pg_stat_activity  where pid <> pg_backend_pid() group by 1 order by 1;

CSS Selector "(A or B) and C"?

is there a better syntax?

No. CSS' or operator (,) does not permit groupings. It's essentially the lowest-precedence logical operator in selectors, so you must use .a.c,.b.c.

Read next word in java

you're better off reading a line and then doing a split.

File file = new File("path/to/file");
String words[]; // I miss C
String line;
HashMap<String, String> hm = new HashMap<>();
try (BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file), "UTF-8")))
    while((line = br.readLine() != null)){
        words = line.split("\\s");
        if (hm.containsKey(words[0])){
                System.out.println("Found duplicate ... handle logic");
        hm.put(words[0],words[1]); //if index==0 is ur key

} catch (FileNotFoundException e) {
} catch (IOException e) {

Difference between using bean id and name in Spring configuration file

Both id and name are bean identifiers in Spring IOC container/ApplicationContecxt. The id attribute lets you specify exactly one id but using name attribute you can give alias name to that bean.

You can check the spring doc here.

Get all table names of a particular database by SQL query?

Building from Michael Baylon's answer, I needed a list which also included schema information and this is how I modified his query.

SELECT TABLE_SCHEMA + '.' + TABLE_NAME as 'Schema.Table'

Function pointer as parameter

The correct way to do this is:

typedef void (*callback_function)(void); // type for conciseness

callback_function disconnectFunc; // variable to store function pointer type

void D::setDisconnectFunc(callback_function pFunc)
    disconnectFunc = pFunc; // store

void D::disconnected()
    disconnectFunc(); // call
    connected = false;

Pythonic way to combine FOR loop and IF statement

a = [2,3,4,5,6,7,8,9,0]
xyz = [0,12,4,6,242,7,9]  
set(a) & set(xyz)  
set([0, 9, 4, 6, 7])

pow (x,y) in Java

In Java x ^ y is an XOR operation.

Getting index value on razor foreach

Or you could simply do this:

@foreach(var myItem in Model.Members)

Removing Spaces from a String in C?

In C, you can replace some strings in-place, for example a string returned by strdup():

char *str = strdup(" a b c ");

char *write = str, *read = str;
do {
   if (*read != ' ')
       *write++ = *read;
} while (*read++);

printf("%s\n", str);

Other strings are read-only, for example those declared in-code. You'd have to copy those to a newly allocated area of memory and fill the copy by skipping the spaces:

char *oldstr = " a b c ";

char *newstr = malloc(strlen(oldstr)+1);
char *np = newstr, *op = oldstr;
do {
   if (*op != ' ')
       *np++ = *op;
} while (*op++);

printf("%s\n", newstr);

You can see why people invented other languages ;)

Copy file remotely with PowerShell

None of the above answers worked for me. I kept getting this error:

Copy-Item : Access is denied
+ CategoryInfo          : PermissionDenied: (\\\Shared\test.txt:String) [Copy-Item], UnauthorizedAccessException>   
+ FullyQualifiedErrorId : ItemExistsUnauthorizedAccessError,Microsoft.PowerShell.Commands.CopyItemCommand

So this did it for me:

netsh advfirewall firewall set rule group="File and Printer Sharing" new enable=yes

Then from my host my machine in the Run box I just did this:

\\{IP address of nanoserver}\C$

How to get the selected item from ListView?

By default, when you click on a ListView item it doesn't change its state to "selected". So, when the event fires and you do:


The method doesn't have anything to return. What you have to do is to use the position and obtain the underlying object by doing:


Immutable array in Java

Another one answer

static class ImmutableArray<T> {
    private final T[] array;

    private ImmutableArray(T[] a){
        array = Arrays.copyOf(a, a.length);

    public static <T> ImmutableArray<T> from(T[] a){
        return new ImmutableArray<T>(a);

    public T get(int index){
        return array[index];

    final ImmutableArray<String> sample = ImmutableArray.from(new String[]{"a", "b", "c"});

How to find which columns contain any NaN value in Pandas dataframe

You can use df.isnull().sum(). It shows all columns and the total NaNs of each feature.

Create Elasticsearch curl query for not null and not empty("")

The only solution here that worked for me in 5.6.5 was bigstone1998's regex answer. I'd prefer not to use a regex search though for performance reasons. I believe the reason the other solutions don't work is because a standard field will be analyzed and as a result have no empty string token to negate against. The exists query won't help on it's own either since an empty string is considered non-null.

If you can't change the index the regex approach may be your only option, but if you can change the index then adding a keyword subfield will solve the problem.

In the mappings for the index:

"myfield": {
    "type": "text",
    "fields": {
        "keyword": {
            "ignore_above": 256,
            "type": "keyword"

Then you can simply use the query:

  "query": {
    "bool": {
      "must": {
        "exists": {
          "field": "myfield"
      "must_not": {
        "term": {
          "myfield.keyword": ""

Note the .keyword in the must_not component.

How to properly override clone method?

As much as the most of the answers here are valid, I need to tell that your solution is also how the actual Java API developers do it. (Either Josh Bloch or Neal Gafter)

Here is an extract from openJDK, ArrayList class:

public Object clone() {
    try {
        ArrayList<?> v = (ArrayList<?>) super.clone();
        v.elementData = Arrays.copyOf(elementData, size);
        v.modCount = 0;
        return v;
    } catch (CloneNotSupportedException e) {
        // this shouldn't happen, since we are Cloneable
        throw new InternalError(e);

As you have noticed and others mentioned, CloneNotSupportedException has almost no chance to be thrown if you declared that you implement the Cloneable interface.

Also, there is no need for you to override the method if you don't do anything new in the overridden method. You only need to override it when you need to do extra operations on the object or you need to make it public.

Ultimately, it is still best to avoid it and do it using some other way.

How to use a WSDL

Use WSDL.EXE utility to generate a Web Service proxy from WSDL.

You'll get a long C# source file that contains a class that looks like this:

/// <remarks/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("wsdl", "2.0.50727.42")]
[System.Web.Services.WebServiceBindingAttribute(Name="MyService", Namespace="")]
public partial class MyService : System.Web.Services.Protocols.SoapHttpClientProtocol {

In your client-side, Web-service-consuming code:

  1. instantiate MyService.
  2. set its Url property
  3. invoke Web methods

curl_init() function not working

Had this problem but found the answer here:

Had to:

sudo a2dismod php7.0


sudo a2enmod php7.2


sudo service apache2 restart

This was after a system upgrade to next version of Ubuntu. All the other answers I found were stale, due to a bad cert apparently on the PPA most of them pointed out, but would probably not have worked anyway. The real issue was disabling the old versions of php, apparently.

Found the solution here:

Java String to Date object of the format "yyyy-mm-dd HH:mm:ss"

its work for me SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); sdf.format(new Date));

OVER clause in Oracle

You can use it to transform some aggregate functions into analytic:

FROM    mytable

will return 1 row with a single maximum,

FROM    mytable

will return all rows with a running maximum.

PostgreSQL, checking date relative to "today"

You could also check using the age() function

select * from mytable where age( mydate, now() ) > '1 year';

age() wil return an interval.

For example age( '2015-09-22', now() ) will return -1 years -7 days -10:56:18.274131

See postgresql documentation

Python os.path.join on Windows

Windows has a concept of current directory for each drive. Because of that, "c:sourcedir" means "sourcedir" inside the current C: directory, and you'll need to specify an absolute directory.

Any of these should work and give the same result, but I don't have a Windows VM fired up at the moment to double check:

os.path.join("/", "c:", "sourcedir")
os.path.join("c:/", "sourcedir")

Can't install Scipy through pip

For windows(7 in my case):

  1. download scipy-0.19.1-cp36-cp36m-win32.whl from
  2. create one some.bat file with content

    @echo off C:\Python36\python.exe -m pip -V C:\Python36\python.exe -m pip install scipy-0.19.1-cp36-cp36m-win32.whl C:\Python36\python.exe -m pip list pause

  3. then run this batch file some.bat

  4. call python shell "C:\Python36\pythonw.exe "C:\Python36\Lib\idlelib\idle.pyw" and test if scipy was installed with

import scipy

Delete all but the most recent X files in bash

fileCount=$(ls -1 *.log | wc -l)
tailCount=$((fileCount - leaveCount))

# avoid negative tail argument
[[ $tailCount < 0 ]] && tailCount=0

ls -t *.log | tail -$tailCount | xargs rm -f

Grouped bar plot in ggplot

First you need to get the counts for each category, i.e. how many Bads and Goods and so on are there for each group (Food, Music, People). This would be done like so:

raw <- read.csv("",sep=",")
raw[,2]<-factor(raw[,2],levels=c("Very Bad","Bad","Good","Very Good"),ordered=FALSE)
raw[,3]<-factor(raw[,3],levels=c("Very Bad","Bad","Good","Very Good"),ordered=FALSE)
raw[,4]<-factor(raw[,4],levels=c("Very Bad","Bad","Good","Very Good"),ordered=FALSE)

raw=raw[,c(2,3,4)] # getting rid of the "people" variable as I see no use for it

freq=table(col(raw), as.matrix(raw)) # get the counts of each factor level

Then you need to create a data frame out of it, melt it and plot it:

Names=c("Food","Music","People")     # create list of names
data=data.frame(cbind(freq),Names)   # combine them into a data frame
data=data[,c(5,3,1,2,4)]             # sort columns

# melt the data frame for plotting
data.m <- melt(data, id.vars='Names')

# plot everything
ggplot(data.m, aes(Names, value)) +   
  geom_bar(aes(fill = variable), position = "dodge", stat="identity")

Is this what you're after?

enter image description here

To clarify a little bit, in ggplot multiple grouping bar you had a data frame that looked like this:

> head(df)
1  1    A  1980   450   338   154    36    13     9
2  2    A  2000   288   407   212    54    16    23
3  3    A  2020   196   434   246    68    19    36
4  4    B  1980   111   326   441    90    21    11
5  5    B  2000    63   298   443   133    42    21
6  6    B  2020    36   257   462   162    55    30

Since you have numerical values in columns 4-9, which would later be plotted on the y axis, this can be easily transformed with reshape and plotted.

For our current data set, we needed something similar, so we used freq=table(col(raw), as.matrix(raw)) to get this:

> data
   Names Very.Bad Bad Good Very.Good
1   Food        7   6    5         2
2  Music        5   5    7         3
3 People        6   3    7         4

Just imagine you have Very.Bad, Bad, Good and so on instead of X1PCE, X2PCE, X3PCE. See the similarity? But we needed to create such structure first. Hence the freq=table(col(raw), as.matrix(raw)).

Android button background color

If you want to keep the general styling (rounded corners etc.) and just change the background color then I use the backgroundTint property


Script parameters in Bash

In bash $1 is the first argument passed to the script, $2 second and so on

/usr/local/bin/abbyyocr9 -rl Swedish -if "$1" -of "$2" 2>&1

So you can use:

./ some_source_file.png destination_file.txt

Explanation on double quotes;

consider three scripts:

bash $1

# cat
bash "$1"

echo "1-$1" "2-$2"

Now invoke:

$ bash "a b"
1-a 2-b

$ bash "a b"
1-a b 2-

When you invoke "a b" then it invokes a b (two arguments), and with "a b" it invokes "a b" (1 argument). Always have in mind how parameters are passed and expaned in bash, it will save you a lot of headache.

How do I make a Docker container start automatically on system boot?

To start a container and set it to restart automatically on system reboot use

docker run -d --restart unless-stopped ecstatic_ritchie

Where ecstatic_ritchie is an example name specifying the container in interest. Use docker ps -a to list all container names.

To make particular running containers start automatically on system reboot

docker update --restart unless-stopped ecstatic_ritchie

To make all running containers start automatically on system reboot

docker update --restart unless-stopped $(docker ps -q)

See more on Docker homepage

SEVERE: ContainerBase.addChild: start:org.apache.catalina.LifecycleException: Failed to start error

In my case the servlet name defined in the web.xml was not same as the sevlet name in the servlet mapping tag. I have corrected this and the WAR was deployed successfully.

Laravel Migration table already exists, but I want to add new not the older

I solved your problem by deleting the "user" table in sequel-pro (there is no data in my user table) and then you can run php artisan migrate

Here are before and after screen shots

before I delete the user table user

enter image description here

after I delete the table user enter image description here

MIN and MAX in C

If you need min/max in order to avoid an expensive branch, you shouldn't use the ternary operator, as it will compile down to a jump. The link below describes a useful method for implementing a min/max function without branching.

Difference between return 1, return 0, return -1 and exit?

return in function return execution back to caller and exit from function terminates the program.

in main function return 0 or exit(0) are same but if you write exit(0) in different function then you program will exit from that position.

returning different values like return 1 or return -1 means that program is returning error .

When exit(0) is used to exit from program, destructors for locally scoped non-static objects are not called. But destructors are called if return 0 is used.

datatable jquery - table header width not aligned with body width answer to problem was totally correct but his solution will not work in all cases. A more general approach is to add the following outside your document.ready function:

$(document).on( 'init.dt', function ( e, settings ) {
    var api = new $.fn.dataTable.Api( settings );
    window.setTimeout(function () {
} );

How to correctly use "section" tag in HTML5?

In the W3 wiki page about structuring HTML5, it says:

<section>: Used to either group different articles into different purposes or subjects, or to define the different sections of a single article.

And then displays an image that I cleaned up:

enter image description here

It's also important to know how to use the <article> tag (from the same W3 link above):

<article> is related to <section>, but is distinctly different. Whereas <section> is for grouping distinct sections of content or functionality, <article> is for containing related individual standalone pieces of content, such as individual blog posts, videos, images or news items. Think of it this way - if you have a number of items of content, each of which would be suitable for reading on their own, and would make sense to syndicate as separate items in an RSS feed, then <article> is suitable for marking them up.

In our example, <section id="main"> contains blog entries. Each blog entry would be suitable for syndicating as an item in an RSS feed, and would make sense when read on its own, out of context, therefore <article> is perfect for them:

<section id="main">
      <!-- first blog post -->

      <!-- second blog post  -->

      <!-- third blog post -->

Simple huh? Be aware though that you can also nest sections inside articles, where it makes sense to do so. For example, if each one of these blog posts has a consistent structure of distinct sections, then you could put sections inside your articles as well. It could look something like this:

  <section id="introduction">

  <section id="content">

  <section id="summary">

Pandas groupby: How to get a union of strings

Named aggregations with pandas >= 0.25.0

Since pandas version 0.25.0 we have named aggregations where we can groupby, aggregate and at the same time assign new names to our columns. This way we won't get the MultiIndex columns, and the column names make more sense given the data they contain:

aggregate and get a list of strings

grp = df.groupby('A').agg(B_sum=('B','sum'),
                          C=('C', list)).reset_index()

   A     B_sum               C
0  1  1.615586  [This, string]
1  2  0.421821         [is, !]
2  3  0.463468             [a]
3  4  0.643961        [random]

aggregate and join the strings

grp = df.groupby('A').agg(B_sum=('B','sum'),
                          C=('C', ', '.join)).reset_index()

   A     B_sum             C
0  1  1.615586  This, string
1  2  0.421821         is, !
2  3  0.463468             a
3  4  0.643961        random

Convert from List into IEnumerable format

You don't need to convert it. List<T> implements the IEnumerable<T> interface so it is already an enumerable.

This means that it is perfectly fine to have the following:

public IEnumerable<Book> GetBooks()
    List<Book> books = FetchEmFromSomewhere();    
    return books;

as well as:

public void ProcessBooks(IEnumerable<Book> books)
    // do something with those books

which could be invoked:

List<Book> books = FetchEmFromSomewhere();    

Android basics: running code in the UI thread

None of those are precisely the same, though they will all have the same net effect.

The difference between the first and the second is that if you happen to be on the main application thread when executing the code, the first one (runOnUiThread()) will execute the Runnable immediately. The second one (post()) always puts the Runnable at the end of the event queue, even if you are already on the main application thread.

The third one, assuming you create and execute an instance of BackgroundTask, will waste a lot of time grabbing a thread out of the thread pool, to execute a default no-op doInBackground(), before eventually doing what amounts to a post(). This is by far the least efficient of the three. Use AsyncTask if you actually have work to do in a background thread, not just for the use of onPostExecute().

Is it possible to specify condition in Count()?

Here is what I did to get a data set that included both the total and the number that met the criteria, within each shipping container. That let me answer the question "How many shipping containers have more than X% items over size 51"

   COUNT (UniqueID) as Total,
   SUM (
         Size > 51 
) as NumOverSize 
   customer like '%PEPSI%' 
group by
   Schedule, PackageNum

adding css class to multiple elements

try this:

.button input, .button a {
//css here

That will apply the style to all a tags nested inside of <p class="button"></p>

how to configure apache server to talk to HTTPS backend server?

In my case, my server was configured to work only in https mode, and error occured when I try to access http mode. So changing http://my-service to https://my-service helped.

Conda: Installing / upgrading directly from github

The answers are outdated. You simply have to conda install pip and git. Then you can use pip normally:

  1. Activate your conda environment source activate myenv

  2. conda install git pip

  3. pip install git+git://

Bash script plugin for Eclipse?

EDIT (8/3/2013): Use for latest version

EDIT (2/25/2013): Non need to install linux tool for shelled 2.0.2 on Eclipse 4.2.1. Also, no need to download zip file. Here's the update site of shelled 2.0.2:


I like Shelled as well. If you install it now, you need to download the zip file and point to it in the install new software wizard in Eclipse. You'll also need to install the man plugin from

How do you set the Content-Type header for an HttpClient request?

Ok, it's not HTTPClient but if u can use it, WebClient is quite easy:

using (var client = new System.Net.WebClient())
    client.Headers.Add("Accept", "application/json");
    client.Headers.Add("Content-Type", "application/json; charset=utf-8");

Attribute Error: 'list' object has no attribute 'split'

The problem is that readlines is a list of strings, each of which is a line of filename. Perhaps you meant:

for line in readlines:
    Type = line.split(",")
    x = Type[1]
    y = Type[2]

Set selected radio from radio group with a value

Or you can just write value attribute to it:


This works for me.

How to check if a file exists in the Documents directory in Swift?

works at Swift 5

    do {
        let documentDirectory = try FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
        let fileUrl = documentDirectory.appendingPathComponent("userInfo").appendingPathExtension("sqlite3")
        if FileManager.default.fileExists(atPath: fileUrl.path) {
            print("FILE AVAILABLE")
        } else {
            print("FILE NOT AVAILABLE")
    } catch {

where "userInfo" - file's name, and "sqlite3" - file's extension

How to provide a mysql database connection in single file in nodejs

I think that you should use a connection pool instead of share a single connection. A connection pool would provide a much better performance, as you can check here.

As stated in the library documentation, it occurs because the MySQL protocol is sequential (this means that you need multiple connections to execute queries in parallel).

Connection Pool Docs

Set bootstrap modal body height by percentage

This should work for everyone, any screen resolutions:

.modal-body {
    max-height: calc(100vh - 143px);
    overflow-y: auto; }

First, count your modal header and footer height, in my case I have H4 heading so I have them on 141px, already counted default modal margin in 20px(top+bottom).

So that subtract 141px is the max-height for my modal height, for the better result there are both border top and bottom by 1px, for this, 143px will work perfectly.

In some case of styling you may like to use overflow-y: auto; instead of overflow-y: scroll;, try it.

Try it, and you get the best result in both computer or mobile devices. If you have a heading larger than H4, recount it see how much px you would like to subtract.

If you don't know what I am telling, just change the number of 143px, see what is the best result for your case.

Last, I'd suggest have it an inline CSS.

How to run only one unit test class using Gradle

Below is the command to run a single test class using gradlew command line option:

gradlew.bat Connected**your bundleVariant**AndroidTest -Pandroid.testInstrumentationRunnerArguments.class=com.example.TestClass

Below example to run class com.example.TestClass with variant Variant_1:

gradlew.bat ConnectedVariant_1AndroidTest -Pandroid.testInstrumentationRunnerArguments.class=com.example.TestClass 

vertical divider between two columns in bootstrap

Well here's another option which I've been using for some time now. It works great for me since I mostly need it do visually separate 2 cols. And it's also responsive. Which means that if I have columns next to each other in medium and large screen sizes, then I would use the class col-md-border, which would hide the separator on smaller screen sizes.


@media (min-width: 992px) {
    .col-md-border:not(:last-child) {
        border-right: 1px solid #d7d7d7;
    .col-md-border + .col-md-border {
        border-left: 1px solid #d7d7d7;
        margin-left: -1px;

In scss you can generate all needed classes probably from this:


@media(min-width: $screen-md-min) {
    .col-md-border {
        &:not(:last-child) {
            border-right: 1px solid #d7d7d7;

        & + .col-md-border {
            border-left: 1px solid #d7d7d7;
            margin-left: -1px;


<div class="row">
    <div class="col-md-6 col-md-border"></div>
    <div class="col-md-6 col-md-border"></div>

How it works:

The cols must be inside an element where there are no other cols otherwise the selectors might not work as expected.

.col-md-border:not(:last-child) matches all but the last element before .row close and adds right border to it.

.col-md-border + .col-md-border matches the second div with the same class if these two are next to each other and adds left border and -1px negative margin. Negative margin is why it doesn't matter anymore which column has greater height and the separator will be 1px the same height as the highest column.

It does also have some problems...

  1. When you try to be clever/lazy and use col-XX-X class together with hidden-XX/visible-XX classes inside the same row element.
  2. When you have a lot of columns and need a pixel perfect thing. Since it moves n-1 column 1px to the left.

... But on the other hand it's responsive, works great for simple html and it's easy to create these classes for all bootstrap screen sizes.

Which MIME type to use for a binary file that's specific to my program?

mimetype headers are recognised by the browser for the purpose of a (fast) possible identifying a handler to use the downloaded file as target, for example, PDF would be downloaded and your Adobe Reader program would be executed with the path of the PDF file as an argument,

If your needs are to write a browser extension to handle your downloaded file, through your operation-system, or you simply want to make you project a more 'professional looking' go ahead and select a unique mimetype for you to use, it would make no difference since the operation-system would have no handle to open it with (some browsers has few bundled-plugins, for example new Google Chrome versions has a built-in PDF-reader),

if you want to make sure the file would be downloaded have a look at this answer:

if you want to make your file type especially organised, it might be worth adding a few letters in the first few bytes of the file, for example, every JPG has this at it's file start:

if you can afford a jump of 4 or 8 bytes it could be very helpful for you in the rest of the way


How to get the first and last date of the current year?

In Microsoft SQL Server (T-SQL) this can be done as follows

--beginning of year

--end of year

CURRENT_TIMESTAMP - returns the sql server date at the time of execution of the query.

YEAR - gets the year part of the current time stamp.

STR , LTRIM - these two functions are applied so that we can convert this into a varchar that can be concatinated with our desired prefix (in this case it's either first date of the year or the last date of the year). For whatever reason the result generated by the YEAR function has prefixing spaces. To fix them we use the LTRIM function which is left trim.

Why does ASP.NET webforms need the Runat="Server" attribute?

It's there because all controls in ASP .NET inherit from System.Web.UI.Control which has the "runat" attribute.

in the class System.Web.UI.HTMLControl, the attribute is not required, however, in the class System.Web.UI.WebControl the attribute is required.

edit: let me be more specific. since is pretty much an abstract of HTML, the compiler needs some sort of directive so that it knows that specific tag needs to run server-side. if that attribute wasn't there then is wouldn't know to process it on the server first. if it isn't there it assumes it is regular markup and passes it to the client.

Calculate execution time of a SQL query?

declare @sttime  datetime
set @sttime=getdate()
print @sttime
Select * from ProductMaster   

Box shadow for bottom side only

-webkit-box-shadow: 0 3px 5px -3px #000;
-moz-box-shadow: 0 3px 5px -3px #000;
box-shadow: 0 3px 5px -3px #000;

Dismissing a Presented View Controller

In addition to Michael Enriquez's answer, I can think of one other reason why this may be a good way to protect yourself from an undetermined state:

Say ViewControllerA presents ViewControllerB modally. But, since you may not have written the code for ViewControllerA you aren't aware of the lifecycle of ViewControllerA. It may dismiss 5 seconds (say) after presenting your view controller, ViewControllerB.

In this case, if you were simply using dismissViewController from ViewControllerB to dismiss itself, you would end up in an undefined state--perhaps not a crash or a black screen but an undefined state from your point of view.

If, instead, you were using the delegate pattern, you would be aware of the state of ViewControllerB and you can program for a case like the one I described.

Angularjs: Get element in controller

Create custom directive

masterApp.directive('ngRenderCallback', function() {
    return {
        restrict: "A",
        link: function ($scope, element, attrs) {
                $scope[attrs.ngEl] = element[0];
            }, 30);

code for html template

<div ng-render-callback="fnRenderCarousel('carouselA')" ng-el="carouselA"></div>

function in controller

$scope.fnRenderCarousel = function(elName){

How do I extract specific 'n' bits of a 32-bit unsigned integer in C?

Instead of thinking of it as 'extracting', I like to think of it as 'isolating'. Once the desired bits are isolated, you can do what you will with them.

To isolate any set of bits, apply an AND mask.

If you want the last X bits of a value, there is a simple trick that can be used.

unsigned  mask;
mask = (1 << X) - 1;
lastXbits = value & mask;

If you want to isolate a run of X bits in the middle of 'value' starting at 'startBit' ...

unsigned  mask;
mask = ((1 << X) - 1) << startBit;
isolatedXbits = value & mask;

Hope this helps.

Unsafe JavaScript attempt to access frame with URL

The problem is even if you create a proxy or load the content and inject it as if it's local, any scripts that that content defines will be loaded from the other domain and cause cross-domain problems.

Jackson - How to process (deserialize) nested JSON?

I'm quite late to the party, but one approach is to use a static inner class to unwrap values:

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

class Scratch {
    private final String aString;
    private final String bString;
    private final String cString;
    private final static String jsonString;

    static {
        jsonString = "{\n" +
                "  \"wrap\" : {\n" +
                "    \"A\": \"foo\",\n" +
                "    \"B\": \"bar\",\n" +
                "    \"C\": \"baz\"\n" +
                "  }\n" +

    Scratch(@JsonProperty("A") String aString,
            @JsonProperty("B") String bString,
            @JsonProperty("C") String cString) {
        this.aString = aString;
        this.bString = bString;
        this.cString = cString;

    public String toString() {
        return "Scratch{" +
                "aString='" + aString + '\'' +
                ", bString='" + bString + '\'' +
                ", cString='" + cString + '\'' +

    public static class JsonDeserializer {
        private final Scratch scratch;

        public JsonDeserializer(@JsonProperty("wrap") Scratch scratch) {
            this.scratch = scratch;

        public Scratch getScratch() {
            return scratch;

    public static void main(String[] args) throws JsonProcessingException {
        ObjectMapper objectMapper = new ObjectMapper();
        Scratch scratch = objectMapper.readValue(jsonString, Scratch.JsonDeserializer.class).getScratch();

However, it's probably easier to use objectMapper.configure(SerializationConfig.Feature.UNWRAP_ROOT_VALUE, true); in conjunction with @JsonRootName("aName"), as pointed out by pb2q

Laravel Eloquent limit and offset

laravel have own function skip for offset and take for limit. just like below example of laravel query :-


How do you get a timestamp in JavaScript?

As of writing this, the top answer is 9 years old, and a lot has changed since then - not least, we have near universal support for a non-hacky solution:

If you want to be absolutely certain that this won't break in some ancient (pre ie9) browser, you can put it behind a check, like so:

const currentTimestamp = (! ? +new Date() :;

This will return the milliseconds since epoch time, of course, not seconds.

MDN Documentation on

500 internal server error, how to debug

You can turn on your PHP errors with error_reporting:

ini_set('display_errors', 'on');

Edit: It's possible that even after putting this, errors still don't show up. This can be caused if there is a fatal error in the script. From PHP Runtime Configuration:

Although display_errors may be set at runtime (with ini_set()), it won't have any affect if the script has fatal errors. This is because the desired runtime action does not get executed.

You should set display_errors = 1 in your php.ini file and restart the server.

Exec : display stdout "live"

Don't use exec. Use spawn which is an EventEmmiter object. Then you can listen to stdout/stderr events (spawn.stdout.on('data',callback..)) as they happen.

From NodeJS documentation:

var spawn = require('child_process').spawn,
    ls    = spawn('ls', ['-lh', '/usr']);

ls.stdout.on('data', function (data) {
  console.log('stdout: ' + data.toString());

ls.stderr.on('data', function (data) {
  console.log('stderr: ' + data.toString());

ls.on('exit', function (code) {
  console.log('child process exited with code ' + code.toString());

exec buffers the output and usually returns it when the command has finished executing.

Defining Z order of views of RelativeLayout in Android

Please note, buttons and other elements in API 21 and greater have a high elevation, and therefore ignore the xml order of elements regardless of parent layout. Took me a while to figure that one out.

What is the meaning of single and double underscore before an object name?

Since so many people are referring to Raymond's talk, I'll just make it a little easier by writing down what he said:

The intention of the double underscores was not about privacy. The intention was to use it exactly like this

class Circle(object):

    def __init__(self, radius):
        self.radius = radius

    def area(self):
        p = self.__perimeter()
        r = p / math.pi / 2.0
        return math.pi * r ** 2.0

    def perimeter(self):
        return 2.0 * math.pi * self.radius

    __perimeter = perimeter  # local reference

class Tire(Circle):

    def perimeter(self):
        return Circle.perimeter(self) * 1.25

It's actually the opposite of privacy, it's all about freedom. It makes your subclasses free to override any one method without breaking the others.

Say you don't keep a local reference of perimeter in Circle. Now, a derived class Tire overrides the implementation of perimeter, without touching area. When you call Tire(5).area(), in theory it should still be using Circle.perimeter for computation, but in reality it's using Tire.perimeter, which is not the intended behavior. That's why we need a local reference in Circle.

But why __perimeter instead of _perimeter? Because _perimeter still gives derived class the chance to override:

class Tire(Circle):

    def perimeter(self):
        return Circle.perimeter(self) * 1.25

    _perimeter = perimeter

Double underscores has name mangling, so there's a very little chance that the local reference in parent class get override in derived class. thus "makes your subclasses free to override any one method without breaking the others".

If your class won't be inherited, or method overriding does not break anything, then you simply don't need __double_leading_underscore.

How to create json by JavaScript for loop?

If I want to create JavaScript Object from string generated by for loop then I would JSON to Object approach. I would generate JSON string by iterating for loop and then use any popular JavaScript Framework to evaluate JSON to Object.

I have used Prototype JavaScript Framework. I have two array with keys and values. I iterate through for loop and generate valid JSON string. I use evalJSON() function to convert JSON string to JavaScript object.

Here is example code. Tryout on your FireBug Console

var key = ["color", "size", "fabric"];
var value = ["Black", "XL", "Cotton"];

var json = "{ ";
for(var i = 0; i < key.length; i++) {
    (i + 1) == key.length ? json += "\"" + key[i] + "\" : \"" + value[i] + "\"" : json += "\"" + key[i] + "\" : \"" + value[i] + "\",";
json += " }";
var obj = json.evalJSON(true);

How to write log base(2) in c/c++

You have to include math.h (C) or cmath (C++) Of course keep on mind that you have to follow the maths that we know...only numbers>0.


#include <iostream>
#include <cmath>
using namespace std;

int main(){

How can I close a login form and show the main form without my application closing?

I would do this the other way round.

In the OnLoad event for your Main form show the Logon form as a dialog. If the dialog result of that is OK then allow Main to continue loading, if the result is authentication failure then abort the load and show the message box.

EDIT Code sample(s)

private void MainForm_Load(object sender, EventArgs e)

    LogonForm logon = new LogonForm();

    if (logon.ShowDialog() != DialogResult.OK)
        //Handle authentication failures as necessary, for example:

Another solution would be to show the LogonForm from the Main method in program.cs, something like this:

static void Main()

    LogonForm logon = new LogonForm();


    if (logon.LogonSuccessful)
        Application.Run(new MainForm());

In this example your LogonForm would have to expose out a LogonSuccessful bool property that is set to true when the user has entered valid credentials

How do I repair an InnoDB table?

First of all stop the server and image the disc. There's no point only having one shot at this. Then take a look here.

Purpose of #!/usr/bin/python3 shebang

  1. And this line is how.

  2. It is ignored.

  3. It will fail to run, and should be changed to point to the proper location. Or env should be used.

  4. It will fail to run, and probably fail to run under a different version regardless.

How can prepared statements protect from SQL injection attacks?

The key phrase is need not be correctly escaped. That means that you don't to worry about people trying to throw in dashes, apostrophes, quotes, etc...

It is all handled for you.

Why is Git better than Subversion?

Easy Git has a nice page comparing actual usage of Git and SVN which will give you an idea of what things Git can do (or do more easily) compared to SVN. (Technically, this is based on Easy Git, which is a lightweight wrapper on top of Git.)

Stupid error: Failed to load resource: net::ERR_CACHE_MISS

Try loading the website in another web browser such as Safari. Recently had this problem and for some reason, it worked after loading in a different browser.

List an Array of Strings in alphabetical order

By alphabetical-order I assume the order to be : A|a < B|b < C|c... Hope this is what @Nick is(or was) looking for and the answer follows the above assumption.

I would suggest to have a class implement compare method of Comparator-interface as :

public int compare(Object o1, Object o2) {
    return o1.toString().compareToIgnoreCase(o2.toString());

and from the calling method invoke the Arrays.sort method with custom Comparator as :

Arrays.sort(inputArray, customComparator);

Observed results: input Array : "Vani","Kali", "Mohan","Soni","kuldeep","Arun"

output(Alphabetical-order) is : Arun, Kali, kuldeep, Mohan, Soni, Vani

Output(Natural-order by executing Arrays.sort(inputArray) is : Arun, Kali, Mohan, Soni, Vani, kuldeep

Thus in case of natural ordering, [Vani < kuldeep] which to my understanding of alphabetical-order is not the thing desired.

for more understanding of natural and alphabetical/lexical order visit discussion here

Getting time difference between two times in PHP

You can also use DateTime class:

$time1 = new DateTime('09:00:59');
$time2 = new DateTime('09:01:00');
$interval = $time1->diff($time2);
echo $interval->format('%s second(s)');


1 second(s)

Do you have to put Task.Run in a method to make it async?

When you use Task.Run to run a method, Task gets a thread from threadpool to run that method. So from the UI thread's perspective, it is "asynchronous" as it doesn't block UI thread.This is fine for desktop application as you usually don't need many threads to take care of user interactions.

However, for web application each request is serviced by a thread-pool thread and thus the number of active requests can be increased by saving such threads. Frequently using threadpool threads to simulate async operation is not scalable for web applications.

True Async doesn't necessarily involving using a thread for I/O operations, such as file / DB access etc. You can read this to understand why I/O operation doesn't need threads.

In your simple example,it is a pure CPU-bound calculation, so using Task.Run is fine.

Dots in URL causes 404 with ASP.NET mvc and IIS

Also, (related) check the order of your handler mappings. We had a .ashx with a .svc (e.g. /foo.asmx/bar.svc/path) in the path after it. The .svc mapping was first so 404 for the .svc path which matched before the .asmx. Havn't thought too much but maybe url encodeing the path would take care of this.

Cassandra "no viable alternative at input"

Wrong syntax. Here you are:

insert into user_by_category (game_category,customer_id) VALUES ('Goku','12');


insert into user_by_category ("game_category","customer_id") VALUES ('Kakarot','12');

The second one is normally used for case-sensitive column names.

Format date and time in a Windows batch script

If PowerShell is installed, then you can easily and reliably get the Date/Time in any format you'd like, for example:

for /f %%a in ('powershell -Command "Get-Date -format yyyy_MM_dd__HH_mm_ss"') do set datetime=%%a
move "%oldfile%" "backup-%datetime%"

Of course nowadays PowerShell is always installed, but on Windows XP you'll probably only want to use this technique if your batch script is being used in a known environment where you know PS is available (or check in your batch file if PowerShell is available...)

You may reasonably ask: why use a batch file at all if you can use PowerShell to get the date/time, but I think some obvious reasons are: (a) you're not all that familiar with PowerShell and still prefer to do most things the old-fashioned way with batch files or (b) you're updating an old script and don't want to port the whole thing to PS.

Excel VBA: Copying multiple sheets into new workbook

This worked for me (I added an "if sheet visible" because in my case I wanted to skip hidden sheets)

   Sub Create_new_file()

Application.DisplayAlerts = False

Dim wb As Workbook
Dim wbNew As Workbook
Dim sh As Worksheet
Dim shNew As Worksheet
Dim pname, parea As String

Set wb = ThisWorkbook
Set wbNew = ActiveWorkbook

For Each sh In wb.Worksheets

    pname = sh.Name

    If sh.Visible = True Then

    sh.Copy After:=wbNew.Sheets(Sheets.Count)



    With Selection

        .PasteSpecial (xlValues)
        .PasteSpecial (xlFormats)
        .PasteSpecial (xlPasteColumnWidths)

    End With

    ActiveSheet.Name = pname

    End If



Application.DisplayAlerts = True

End Sub

Exception: "URI formats are not supported"

I solved the same error with the Path.Combine(MapPath()) to get the physical file path instead of the http:/// www one.

Auto number column in SharePoint list

Sharepoint Lists automatically have an column with "ID" which auto increments. You simply need to select this column from the "modify view" screen to view it.

Read file line by line using ifstream in C++

This is a general solution to loading data into a C++ program, and uses the readline function. This could be modified for CSV files, but the delimiter is a space here.

int n = 5, p = 2;

int X[n][p];

ifstream myfile;"data.txt");

string line;
string temp = "";
int a = 0; // row index 

while (getline(myfile, line)) { //while there is a line
     int b = 0; // column index
     for (int i = 0; i < line.size(); i++) { // for each character in rowstring
          if (!isblank(line[i])) { // if it is not blank, do this
              string d(1, line[i]); // convert character to string
              temp.append(d); // append the two strings
        } else {
              X[a][b] = stod(temp);  // convert string to double
              temp = ""; // reset the capture
              b++; // increment b cause we have a new number

  X[a][b] = stod(temp);
  temp = "";
  a++; // onto next row

Simple http post example in Objective-C?

From Apple's Official Website :

// In body data for the 'application/x-www-form-urlencoded' content type,
// form fields are separated by an ampersand. Note the absence of a
// leading ampersand.
NSString *bodyData = @"name=Jane+Doe&address=123+Main+St";

NSMutableURLRequest *postRequest = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@""]];

// Set the request's content type to application/x-www-form-urlencoded
[postRequest setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];

// Designate the request a POST request and specify its body data
[postRequest setHTTPMethod:@"POST"];
[postRequest setHTTPBody:[NSData dataWithBytes:[bodyData UTF8String] length:strlen([bodyData UTF8String])]];

// Initialize the NSURLConnection and proceed as described in
// Retrieving the Contents of a URL

From : code with chris

    // Create the request.
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@""]];

// Specify that it will be a POST request
request.HTTPMethod = @"POST";

// This is how we set header fields
[request setValue:@"application/xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];

// Convert your data and set your request's HTTPBody property
NSString *stringData = @"some data";
NSData *requestBodyData = [stringData dataUsingEncoding:NSUTF8StringEncoding];
request.HTTPBody = requestBodyData;

// Create url connection and fire request
NSURLConnection *conn = [[NSURLConnection alloc] initWithRequest:request delegate:self];

Set initial value in datepicker with jquery?

This simple example works for me...


<input type="text" id="datepicker">


var $datepicker = $('#datepicker');
$datepicker.datepicker('setDate', new Date());

I was able to create this by simply looking @ the manual and reading the explanation of setDate:

.datepicker( "setDate" , date )
Sets the current date for the datepicker. The new date may be a Date object or a string in the current date format (e.g. '01/26/2009'), a number of days from today (e.g. +7) or a string of values and periods ('y' for years, 'm' for months, 'w' for weeks, 'd' for days, e.g. '+1m +7d'), or null to clear the selected date.

What does the error "arguments imply differing number of rows: x, y" mean?

Though this isn't a DIRECT answer to your question, I just encountered a similar problem, and thought I'd mentioned it:

I had an instance where it was instantiating a new (no doubt very inefficent) record for data.frame (a result of recursive searching) and it was giving me the same error.

I had this:

    user_id = gift$email,
    sourced_from_agent_id = gift$source,
    method_used = method,
    given_to = gift$account,
    recurring_subscription_id = NULL,
    notes = notes,
    stringsAsFactors = FALSE

turns out... it was the = NULL. When I switched to = NA, it worked fine. Just in case anyone else with a similar problem hits THIS post as I did.

.mp4 file not playing in chrome

After running into the same issue - here're some of my thoughts:

  • due to Chrome removing support for h264, on some machines, mp4 videos encoded with it will either not work (throwing an Parser error when viewing under Firebug/Network tab - consistent with issue submitted here), or crash the browser, depending upon the encoding settings
  • it isn't consistent - it entirely depends upon the codecs installed on the computer - while I didn't encounter this issue on my machine, we did have one in the office where the issue occurred (and thus we used this one for testing)
  • it might to do with Quicktime / divX settings (the machine in question had an older version of Quicktime than my native one - we didn't want to loose our testing pc though, so we didn't update it).

As it affects only Chrome (other browsers work fine with VideoForEverybody solution) the solution I've used is:

for every mp4 file, create a Theora encoded mp4 file (example.mp4 -> example_c.mp4) apply following js:

if (
        $(this).attr('src', $(this).attr('src').replace(".mp4", "_c.mp4"));

Unfortunately it's a bad Chrome hack, but hey, at least it works.

Source: user: eithedog

This also can help: chrome could play html5 mp4 video but html5test said chrome did not support mp4 video codec

Also check your version of crome here: html5test

How to select all the columns of a table except one column?

Without creating new table you can do simply (e.g with mysqli):

  1. get all columns
  2. loop through all columns and remove wich you want
  3. make your query

$r = mysqli_query('SELECT column_name FROM information_schema.columns WHERE table_name = table_to_query');

$c = count($r); while($c--) if($r[$c]['column_name'] != 'column_to_remove_from_query') $a[] = $r[$c]['column_name']; else unset($r[$c]);

$r = mysqli_query('SELECT ' . implode(',', $a) . ' FROM table_to_query');

Adding open/closed icon to Twitter Bootstrap collapsibles (accordions)


RE Martin Wickman's CSS only version...

You can get around that problem by putting accordion-caret on the anchor tag and giving it a collapsed class by default. Like so:

<div class="accordion-group">
<div class="accordion-heading">
    <a class="accordion-toggle accordion-caret collapsed" data-toggle="collapse" href="#collapseOne">
<div id="collapseOne" class="accordion-body collapse in">
    <div class="accordion-inner">

That worked for me.

first-child and last-child with IE8

If you want to carry on using CSS3 selectors but need to support older browsers I would suggest using a polyfill such as Selectivizr.js

What does MissingManifestResourceException mean and how to fix it?

I had the with a newly created F# project. The solution was to uncheck "Use standard resource names" in the project properties -> Application -> Resources / Specify how application resources will be managed. If you do not see the checkbox then update your Visual Studio! I have 15.6.7 installed. In 15.3.2 this checkbox is not there.

The split() method in Java does not work on a dot (.)


String words[]=temp.split("\\.");

The method is:

String[] split(String regex) 

"." is a reserved char in regex

php, mysql - Too many connections to database error

Please check if you open up a new connection with each of your requests (mysql_connect(...)). If you do so, make sure you close the connection afterwards (using mysql_close($link)).

Also, you should consider changing this behaviour as keeping one steady connection for each user may be a better way to accomplish your task.

If you didn't already, take a look at this obvious, but nonetheless useful information resource:

How do I sort a vector of pairs based on the second element of the pair?

You can use boost like this:

std::sort(a.begin(), a.end(), 
          boost::bind(&std::pair<int, int>::second, _1) <
          boost::bind(&std::pair<int, int>::second, _2));

I don't know a standard way to do this equally short and concise, but you can grab boost::bind it's all consisting of headers.

How can you debug a CORS request with cURL?

Seems like just this works:

curl -I

Look for Access-Control-Allow-Origin: * in the returned headers

C#: what is the easiest way to subtract time?

These can all be done with DateTime.Add(TimeSpan) since it supports positive and negative timespans.

DateTime original = new DateTime(year, month, day, 8, 0, 0);
DateTime updated = original.Add(new TimeSpan(5,0,0));

DateTime original = new DateTime(year, month, day, 17, 0, 0);
DateTime updated = original.Add(new TimeSpan(-2,0,0));

DateTime original = new DateTime(year, month, day, 17, 30, 0);
DateTime updated = original.Add(new TimeSpan(0,45,0));

Or you can also use the DateTime.Subtract(TimeSpan) method analogously.