Programs & Examples On #Django nonrel

Django-nonrel is an independent branch of Django that adds NoSQL database support to the ORM. The long-term goal is to add NoSQL support to the official Django release.

What is the attribute property="og:title" inside meta tag?

The property in meta tags allows you to specify values to property fields which come from a property library. The property library (RDFa format) is specified in the head tag.

For example, to use that code you would have to have something like this in your <head tag. <head xmlns:og=""> and inside the there would be a specification for title (og:title).

The tag from your example was almost definitely from the Open Graph Protocol, the purpose is to specify structured information about your website for the use of Facebook (and possibly other search engines).

Why do we need to install gulp globally and locally?

When installing a tool globally it's to be used by a user as a command line utility anywhere, including outside of node projects. Global installs for a node project are bad because they make deployment more difficult.

npm 5.2+

The npx utility bundled with npm 5.2 solves this problem. With it you can invoke locally installed utilities like globally installed utilities (but you must begin the command with npx). For example, if you want to invoke a locally installed eslint, you can do:

npx eslint .

npm < 5.2

When used in a script field of your package.json, npm searches node_modules for the tool as well as globally installed modules, so the local install is sufficient.

So, if you are happy with (in your package.json):

"devDependencies": {
    "gulp": "3.5.2"
"scripts": {
    "test": "gulp test"

etc. and running with npm run test then you shouldn't need the global install at all.

Both methods are useful for getting people set up with your project since sudo isn't needed. It also means that gulp will be updated when the version is bumped in the package.json, so everyone will be using the same version of gulp when developing with your project.


It appears that gulp has some unusual behaviour when used globally. When used as a global install, gulp looks for a locally installed gulp to pass control to. Therefore a gulp global install requires a gulp local install to work. The answer above still stands though. Local installs are always preferable to global installs.

How do I make a checkbox required on an ASP.NET form?

C# version of andrew's answer:

<asp:CustomValidator ID="CustomValidator1" runat="server" 
        ErrorMessage="Please accept the terms..." 
    <asp:CheckBox ID="CheckBox1" runat="server" />


protected void CustomValidator1_ServerValidate(object source, ServerValidateEventArgs args)
    args.IsValid = CheckBox1.Checked;

difference between variables inside and outside of __init__()

class User(object):
    email = 'none'
    firstname = 'none'
    lastname = 'none'

    def __init__(self, email=None, firstname=None, lastname=None): = email
        self.firstname = firstname
        self.lastname = lastname

    def print_var(cls, obj):
        print (" obj.firstname obj.lastname")
        print(, obj.firstname, obj.lastname)
        print(" cls.firstname cls.lastname")
        print(, cls.firstname, cls.lastname)

u1 = User(email='abc@xyz', firstname='first', lastname='last')

In the above code, the User class has 3 global variables, each with value 'none'. u1 is the object created by instantiating this class. The method print_var prints the value of class variables of class User and object variables of object u1. In the output shown below, each of the class variables, User.firstname and User.lastname has value 'none', while the object variables, u1.firstname and u1.lastname have values 'abc@xyz', 'first' and 'last'. obj.firstname obj.lastname
('abc@xyz', 'first', 'last') cls.firstname cls.lastname
('none', 'none', 'none')

How to remove "onclick" with JQuery?

What if onclick event is not directly on element, but from parent element? This should work:

    return false;

"Multiple definition", "first defined here" errors

I had a similar issue when not using inline for my global function that was included in two places.

Confusion: @NotNull vs. @Column(nullable = false) with JPA and Hibernate

The JPA @Column Annotation

The nullable attribute of the @Column annotation has two purposes:

  • it's used by the schema generation tool
  • it's used by Hibernate during flushing the Persistence Context

Schema Generation Tool

The HBM2DDL schema generation tool translates the @Column(nullable = false) entity attribute to a NOT NULL constraint for the associated table column when generating the CREATE TABLE statement.

As I explained in the Hibernate User Guide, it's better to use a tool like Flyway instead of relying on the HBM2DDL mechanism for generating the database schema.

Persistence Context Flush

When flushing the Persistence Context, Hibernate ORM also uses the @Column(nullable = false) entity attribute:

new Nullability( session ).checkNullability( values, persister, true );

If the validation fails, Hibernate will throw a PropertyValueException, and prevents the INSERT or UPDATE statement to be executed needesly:

if ( !nullability[i] && value == null ) {
    //check basic level one nullablilty
    throw new PropertyValueException(
            "not-null property references a null or transient value",

The Bean Validation @NotNull Annotation

The @NotNull annotation is defined by Bean Validation and, just like Hibernate ORM is the most popular JPA implementation, the most popular Bean Validation implementation is the Hibernate Validator framework.

When using Hibernate Validator along with Hibernate ORM, Hibernate Validator will throw a ConstraintViolation when validating the entity.

error LNK2005, already defined?

Why this error?

You broke the one definition rule and hence the linking error.

Suggested Solutions:

If you need the same named variable in the two cpp files then You need to use Nameless namespace(Anonymous Namespace) to avoid the error.

    int k;

If you need to share the same variable across multiple files then you need to use extern.


extern int k;


#include "A.h"
int k = 0;


#include "A.h"

//Use `k` anywhere in the file 

How to set a Fragment tag by code?

Nowadays there's a simpler way to achieve this if you are using a DialogFragment (not a Fragment):

val yourDialogFragment = YourDialogFragment()

Under the hood, the show() method does create a FragmentTransaction and adds the tag by using the add() method. But it's much more convenient to use the show() method in my opinion.

You could shorten it for Fragment too, by using a Kotlin Extension :)

What is a None value?

None is just a value that commonly is used to signify 'empty', or 'no value here'. It is a signal object; it only has meaning because the Python documentation says it has that meaning.

There is only one copy of that object in a given Python interpreter session.

If you write a function, and that function doesn't use an explicit return statement, None is returned instead, for example. That way, programming with functions is much simplified; a function always returns something, even if it is only that one None object.

You can test for it explicitly:

if foo is None:
    # foo is set to None

if bar is not None:
    # bar is set to something *other* than None

Another use is to give optional parameters to functions an 'empty' default:

def spam(foo=None):
    if foo is not None:
        # foo was specified, do something clever!

The function spam() has a optional argument; if you call spam() without specifying it, the default value None is given to it, making it easy to detect if the function was called with an argument or not.

Other languages have similar concepts. SQL has NULL; JavaScript has undefined and null, etc.

Note that in Python, variables exist by virtue of being used. You don't need to declare a variable first, so there are no really empty variables in Python. Setting a variable to None is then not the same thing as setting it to a default empty value; None is a value too, albeit one that is often used to signal emptyness. The book you are reading is misleading on that point.

Fatal error: Call to undefined function mysql_connect()

Verify that your installation of PHP has been compiled with mysql support. Create a test web page containing <?php phpinfo(); exit(); ?> and load it in your browser. Search the page for MySQL. If you don't see it, you need to recompile PHP with MySQL support, or reinstall a PHP package that has it built-in

exception in thread 'main' java.lang.NoClassDefFoundError:

I had the same problem, and stumbled onto a solution with 'Build Main Project F11'. The ide brought up an "option" that I might want to uncheck 'Compile on Save' in the Build > Compiling portion of the Project configuration dialog. Unchecking 'Complile on Save' and then doing the usual (for me) 'Clean and Build' did the trick for me.

Change one value based on another value in pandas

The original question addresses a specific narrow use case. For those who need more generic answers here are some examples:

Creating a new column using data from other columns

Given the dataframe below:

import pandas as pd
import numpy as np

df = pd.DataFrame([['dog', 'hound', 5],
                   ['cat', 'ragdoll', 1]],
                  columns=['animal', 'type', 'age'])

  animal     type  age
0    dog    hound    5
1    cat  ragdoll    1

Below we are adding a new description column as a concatenation of other columns by using the + operation which is overridden for series. Fancy string formatting, f-strings etc won't work here since the + applies to scalars and not 'primitive' values:

df['description'] = 'A ' + df.age.astype(str) + ' years old ' \
                    + df.type + ' ' + df.animal

In [2]: df
  animal     type  age                description
0    dog    hound    5    A 5 years old hound dog
1    cat  ragdoll    1  A 1 years old ragdoll cat

We get 1 years for the cat (instead of 1 year) which we will be fixing below using conditionals.

Modifying an existing column with conditionals

Here we are replacing the original animal column with values from other columns, and using np.where to set a conditional substring based on the value of age:

# append 's' to 'age' if it's greater than 1
df.animal = df.animal + ", " + df.type + ", " + \
    df.age.astype(str) + " year" + np.where(df.age > 1, 's', '')

In [3]: df
                 animal     type  age
0   dog, hound, 5 years    hound    5
1  cat, ragdoll, 1 year  ragdoll    1

Modifying multiple columns with conditionals

A more flexible approach is to call .apply() on an entire dataframe rather than on a single column:

def transform_row(r):
    r.animal = 'wild ' + r.type
    r.type = r.animal + ' creature'
    r.age = "{} year{}".format(r.age, r.age > 1 and 's' or '')
    return r

df.apply(transform_row, axis=1)

         animal            type      age
0    wild hound    dog creature  5 years
1  wild ragdoll    cat creature   1 year

In the code above the transform_row(r) function takes a Series object representing a given row (indicated by axis=1, the default value of axis=0 will provide a Series object for each column). This simplifies processing since we can access the actual 'primitive' values in the row using the column names and have visibility of other cells in the given row/column.

How to allow only integers in a textbox?

An even easier method is to use the TextMode attribute:

<asp:TextBox runat="server" ID="txtTextBox" TextMode="Number">

Check if a list contains an item in Ansible

Ansible has a version_compare filter since 1.6. You can do something like below in when conditional:

when: ansible_distribution_version | version_compare('12.04', '>=')

This will give you support for major & minor versions comparisons and you can compare versions using operators like:

<, lt, <=, le, >, gt, >=, ge, ==, =, eq, !=, <>, ne

You can find more information about this here: Ansible - Version comparison filters

Otherwise if you have really simple case you can use what @ProfHase85 suggested

Link to Flask static files with url_for

In my case I had special instruction into nginx configuration file:

location ~ \.(js|css|png|jpg|gif|swf|ico|pdf|mov|fla|zip|rar)$ {
            try_files $uri =404;

All clients have received '404' because nginx nothing known about Flask.

I hope it help someone.

Removing leading zeroes from a field in a SQL statement

select CASE
         WHEN TRY_CONVERT(bigint,Mtrl_Nbr) = 0
           THEN ''
           ELSE substring(Mtrl_Nbr, patindex('%[^0]%',Mtrl_Nbr), 18)

if (boolean condition) in Java

Assuming state is having a valid boolean value set in your actual code, then the following condition will succeed


when state is boolean value is TRUE

If condition checks for the expression whether it is evaluated to TRUE/FALSE. If the expression is simple true then the condition will succeed.

What is the difference between __dirname and ./ in node.js?

The gist

In Node.js, __dirname is always the directory in which the currently executing script resides (see this). So if you typed __dirname into /d1/d2/myscript.js, the value would be /d1/d2.

By contrast, . gives you the directory from which you ran the node command in your terminal window (i.e. your working directory) when you use libraries like path and fs. Technically, it starts out as your working directory but can be changed using process.chdir().

The exception is when you use . with require(). The path inside require is always relative to the file containing the call to require.

For example...

Let's say your directory structure is


and pathtest.js contains

var path = require("path");
console.log(". = %s", path.resolve("."));
console.log("__dirname = %s", path.resolve(__dirname));

and you do

cd /dir1/dir2
node pathtest.js

you get

. = /dir1/dir2
__dirname = /dir1/dir2

Your working directory is /dir1/dir2 so that's what . resolves to. Since pathtest.js is located in /dir1/dir2 that's what __dirname resolves to as well.

However, if you run the script from /dir1

cd /dir1
node dir2/pathtest.js

you get

. = /dir1
__dirname = /dir1/dir2

In that case, your working directory was /dir1 so that's what . resolved to, but __dirname still resolves to /dir1/dir2.

Using . inside require...

If inside dir2/pathtest.js you have a require call into include a file inside dir1 you would always do


because the path inside require is always relative to the file in which you are calling it. It has nothing to do with your working directory.

How to call VS Code Editor from terminal / command line

In the case of Linux and Mac, you want to navigate to the directory that you extracted the VSCode files using the 'cd' command. For example:

cd ~/Downloads/VSCode

Then you start the application by running..


'Code' being the name of the executable.

If you have root access on the machine, you can configure the system to allow you to start VSCode from anywhere by linking it to /usr/bin, where links to executables are often stored.

sudo ln -s /path/to/VSCode/folder/Code /usr/bin/Code    

You can now launch VSCode from anywhere by typing:


How to escape % in String.Format?

To complement the previous stated solution, use:

str = str.replace("%", "%%");

Regular expression for exact match of a string

You may also try appending a space at the start and end of keyword: /\s+123456\s+/i.

What is the best way to give a C# auto-property an initial value?

class Person 
    /// Gets/sets a value indicating whether auto 
    /// save of review layer is enabled or not
    public bool AutoSaveReviewLayer { get; set; }

'^M' character at end of lines

The easiest way is to use vi. I know that sounds terrible but its simple and already installed on most UNIX environments. The ^M is a new line from Windows/DOS environment.

from the command prompt: $ vi filename

Then press ":" to get to command mode.

Search and Replace all Globally is :%s/^M//g "Press and hold control then press V then M" which will replace ^M with nothing.

Then to write and quit enter ":wq" Done!

Incrementing in C++ - When to use x++ or ++x?

I agree with @BeowulfOF, though for clarity I would always advocate splitting the statements so that the logic is absolutely clear, i.e.:

x += i;


x += i;

So my answer is if you write clear code then this should rarely matter (and if it matters then your code is probably not clear enough).

Dynamic LINQ OrderBy on IEnumerable<T> / IQueryable<T>

An alternate solution uses the following class/interface. It's not truly dynamic, but it works.

public interface IID
    int ID
        get; set;

public static class Utils
    public static int GetID<T>(ObjectQuery<T> items) where T:EntityObject, IID
        if (items.Count() == 0) return 1;
        return items.OrderByDescending(u => u.ID).FirstOrDefault().ID + 1;

ssh_exchange_identification: Connection closed by remote host under Git bash

Just enter on the server side :

echo 'SSHD: ALL' >> /etc/hosts.allow

It sorted it out for me.

How do I automatically scroll to the bottom of a multiline text box?

I use a function for this :

private void Log (string s) {
    TB1.AppendText(Environment.NewLine + s);

Where to find the win32api module for Python?

I've found that UC Irvine has a great collection of python modules, pywin32 (win32api) being one of many listed there. I'm not sure how they do with keeping up with the latest versions of these modules but it hasn't let me down yet.

UC Irvine Python Extension Repository -

pywin32 module -

WPF - add static items to a combo box

Like this:

<ComboBox Text="MyCombo">
<ComboBoxItem  Name="cbi1">Item1</ComboBoxItem>
<ComboBoxItem  Name="cbi2">Item2</ComboBoxItem>
<ComboBoxItem  Name="cbi3">Item3</ComboBoxItem>

What is 'PermSize' in Java?

lace to store your loaded class definition and metadata. If a large code-base project is loaded, the insufficient Perm Gen size will cause the popular Java.Lang.OutOfMemoryError: PermGen.

css ellipsis on second line

Just use line-clamp for the browsers that support it(most modern browsers) and fall back to 1 line for older.

  .text {
    white-space: nowrap;
    text-overflow: ellipsis;
    overflow: hidden;

    @supports (-webkit-line-clamp: 2) {
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: initial;
      display: -webkit-box;
      -webkit-line-clamp: 2;
      -webkit-box-orient: vertical;

browser support

"Logging out" of phpMyAdmin?

Simple seven step to solve issue in case of WampServer:

  1. Start WampServer
  2. Click on Folder icon Mysql -> Mysql Console
  3. Press Key Enter without password
  4. Execute Statement

    SET PASSWORD FOR root@localhost=PASSWORD('root');
  5. open D:\wamp\apps\phpmyadmin4.1.14\ file set value

    $cfg['Servers'][$i]['auth_type'] = 'cookie';
    $cfg['Servers'][$i]['user'] = '';
  6. Restart All services

  7. Open phpMyAdmin in browser enter user root and pass root

Is there a bash command which counts files?

Here's what I always do:

ls log* | awk 'END{print NR}'

Reset C int array to zero : the fastest way?

zero(myarray); is all you need in C++.

Just add this to a header:

template<typename T, size_t SIZE> inline void zero(T(&arr)[SIZE]){
    memset(arr, 0, SIZE*sizeof(T));

Artisan, creating tables in database

in laravel 5 first we need to create migration and then run the migration

Step 1.

php artisan make:migration create_users_table --create=users

Step 2.

php artisan migrate

XPath using starts-with function



Note: Unless your host language can't handle element instance as result, do not use text nodes specially in mixed content data model. Do not start expressions with // operator when the schema is well known.

TypeError: 'str' object cannot be interpreted as an integer

I'm guessing you're running python3, in which input(prompt) returns a string. Try this.


Visual Studio debugger error: Unable to start program Specified file cannot be found

Guessing from the information I have, you're not actually compiling the program, but trying to run it. That is, ALL_BUILD is set as your startup project. (It should be in a bold font, unlike the other projects in your solution) If you then try to run/debug, you will get the error you describe, because there is simply nothing to run.

The project is most likely generated via CMAKE and included in your Visual Studio solution. Set any of the projects that do generate a .exe as the startup project (by right-clicking on the project and selecting "set as startup project") and you will most likely will be able to start those from within Visual Studio.

Turn a single number into single digits Python

The easiest way is to turn the int into a string and take each character of the string as an element of your list:

>>> n = 43365644 
>>> digits = [int(x) for x in str(n)]
>>> digits
[4, 3, 3, 6, 5, 6, 4, 4]
>>> lst.extend(digits)  # use the extends method if you want to add the list to another

It involves a casting operation, but it's readable and acceptable if you don't need extreme performance.

How to get the range of occupied cells in excel sheet

You should try the currentRegion property, if you know from where you are to find the range. This will give you the boundaries of your used range.

Batch script to find and replace a string in text file within a minute for files up to 12 MB

Give this a shot:

@echo off

call :FindReplace "findstr" "replacestr" input.txt

exit /b 

:FindReplace <findstr> <replstr> <file>
set tmp="%temp%\tmp.txt"
If not exist %temp%\_.vbs call :MakeReplace
for /f "tokens=*" %%a in ('dir "%3" /s /b /a-d /on') do (
  for /f "usebackq" %%b in (`Findstr /mic:"%~1" "%%a"`) do (
    echo(&Echo Replacing "%~1" with "%~2" in file %%~nxa
    <%%a cscript //nologo %temp%\_.vbs "%~1" "%~2">%tmp%
    if exist %tmp% move /Y %tmp% "%%~dpnxa">nul
del %temp%\_.vbs
exit /b

>%temp%\_.vbs echo with Wscript
>>%temp%\_.vbs echo set args=.arguments
>>%temp%\_.vbs echo .StdOut.Write _
>>%temp%\_.vbs echo Replace(.StdIn.ReadAll,args(0),args(1),1,-1,1)
>>%temp%\_.vbs echo end with

Getting Python error "from: can't read /var/mail/Bio"

I got same error because I was trying to run on

XXX-Macmini:Python-Project XXX.XXX$ from classDemo import MyClass

from: can't read /var/mail/classDemo

To solve this, type command python and when you get these >>> then run any python commands

>>>from classDemo import MyClass
>>>f = MyClass()

PHP $_POST not working?

I had something similar this evening which was driving me batty. Submitting a form was giving me the values in $_REQUEST but not in $_POST.

Eventually I noticed that there were actually two requests going through on the network tab in firebug; first a POST with a 301 response, then a GET with a 200 response.

Hunting about the interwebs it sounded like most people thought this was to do with mod_rewrite causing the POST request to redirect and thus change to a GET.

In my case it wasn't mod_rewrite to blame, it was something far simpler... my URL for the POST also contained a GET query string which was starting without a trailing slash on the URL. It was this causing apache to redirect.

Spot the difference...


The bottom one doesn't cause a redirect and gives me $_POST!

What are some great online database modeling tools?

S.Lott inserted a comment, but it should be an answer: see the same question.


Since it wasn't as obvious as I intended it to be, here follows a verbatim copy of S.Lott's answer in the other question:

I'm a big fan of ARGO UML from Draws nice pictures using standard UML notation. It does some code generation, but mostly Java classes, which isn't SQL DDL, so that may not be close enough to what you want to do.

You can look at the Data Modelling Tools list and see if anything there is better than Argo UML. Many of the items on this list are free or cheap.

Also, if you're using Eclipse or NetBeans, there are many design plug-ins, some of which may have the features you're looking for.

How can I schedule a daily backup with SQL Server Express?

We have used the combination of:

  1. Cobian Backup for scheduling/maintenance

  2. ExpressMaint for backup

Both of these are free. The process is to script ExpressMaint to take a backup as a Cobian "before Backup" event. I usually let this overwrite the previous backup file. Cobian then takes a zip/7zip out of this and archives these to the backup folder. In Cobian you can specify the number of full copies to keep, make multiple backup cycles etc.

ExpressMaint command syntax example:

expressmaint -S HOST\SQLEXPRESS -D ALL_USER -T DB -R logpath -RU WEEKS -RV 1 -B backuppath -BU HOURS -BV 3 

Responsive width Facebook Page Plugin

We have overcome some limitations of the responsiveness of the Facebook plugin by using it as an IFRAME, but bootstrapping at render time with some JavaScript that dynamically sizes the frame (and width/height parameters in the SRC URL) to fill the container element.

If the container is greater than 500px, to avoid having an obvious gutter on the right hand side, we simply add a scale transform with some simple math.

The IFRAME onload event fires when SRC is initially empty (when we bootstrap it) and then again after it finishes loading when we set the SRC, but we simply short-out if SRC attribute already exists.

In our usage, we don't change the width of the Facebook feed for desktop usage, and for handheld/tablet viewports, those widths are fixed by nature (yes, we trap orientation change) but if you want yours to continually adjust if the browser window dimensions change, you could just re-fire the code as an exercise for yourself.

This is tested in with Chrome and Safari, on desktop and iOS/Android:

    function setupFBframe(frame) {

        if(frame.src) return; // already set up

        // get parent container dimensions to use in src attrib
        var container = frame.parentNode;

        var containerWidth = container.offsetWidth;
        var containerHeight = container.offsetHeight;

        var src = '' +
                '?' +
                '&tabs=timeline' +
                '&width=' + containerWidth +
                '&height=' + containerHeight +
                '&small_header=true' +
                '&adapt_container_width=false' + /* doesn't seem to matter */
                '&hide_cover=true' +
                '&hide_cta=true' +
                '&show_facepile=false' +

        frame.width = containerWidth;
        frame.height = containerHeight;
        frame.src = src;

        // scale up if container > 500px wide
        if(containerWidth) > 500) {
            var scale = (containerWidth / 500 );
   = 'scale(' + scale + ')';
    #facebook_iframe {
        transform-origin: 0 0;
        -webkit-transform-origin: 0px 0px;
        -moz-transform-origin: 0px 0px;
<iframe frameborder="0" height="0" width="0" onload="var _this = this; window.setTimeout(function(){ setupFBframe(_this); },500 /* let dom settle before eval parent dimensions */ );"></iframe>

EDIT: Forgot about transform-origin, removed need for adjusting left/top to accommodate scale. Thanks Io Ctaptceb

Eloquent ->first() if ->exists()

(ps - I couldn't comment) I think your best bet is something like you've done, or similar to:

$user = User::where('mobile', Input::get('mobile'));
$user->exists() and $user = $user->first();

Oh, also: count() instead if exists but this could be something used after get.

What is a faster alternative to Python's http.server (or SimpleHTTPServer)?

If you have PHP installed you could use the builtin server.

php -S 0:8080

text-align: right on <select> or <option>

The following CSS will right-align both the arrow and the options:

select { text-align-last: right; }_x000D_
option { direction: rtl; }
<!-- example usage -->_x000D_
Choose one: <select>_x000D_
  <option>The first option</option>_x000D_
  <option>A second, fairly long option</option>_x000D_

Check if table exists without using "select from"

This has been my 'go-to' EXISTS procedure that checks both temp and normal tables. This procedure works in MySQL version 5.6 and above. The @DEBUG parameter is optional. The default schema is assumed, but can be concatenated to the table in the @s statement.

drop procedure if exists `prcDoesTableExist`;
delimiter #
CREATE PROCEDURE `prcDoesTableExist`(IN pin_Table varchar(100), OUT pout_TableExists BOOL)
    DECLARE `boolTableExists` TINYINT(1) DEFAULT 1;
    DECLARE CONTINUE HANDLER FOR 1243, SQLSTATE VALUE '42S02' SET `boolTableExists` := 0;
        SET @s = concat('SELECT null FROM `', pin_Table, '` LIMIT 0 INTO @resultNm');
    PREPARE stmt1 FROM @s;
    EXECUTE stmt1;
    set pout_TableExists = `boolTableExists`; -- Set output variable
    IF @DEBUG then
        select IF(`boolTableExists`
            , CONCAT('TABLE `', pin_Table, '` exists: ', pout_TableExists)
            , CONCAT('TABLE `', pin_Table, '` does not exist: ', pout_TableExists)
        ) as result;
    END IF;
delimiter ;

Here is the example call statement with @debug on:

set @DEBUG = true;
call prcDoesTableExist('tempTable', @tblExists);
select @tblExists as '@tblExists';

The variable @tblExists returns a boolean.

How can I calculate an md5 checksum of a directory?

find /path/to/dir/ -type f -name "*.py" -exec md5sum {} + | awk '{print $1}' | sort | md5sum

The find command lists all the files that end in .py. The md5sum is computed for each .py file. awk is used to pick off the md5sums (ignoring the filenames, which may not be unique). The md5sums are sorted. The md5sum of this sorted list is then returned.

I've tested this by copying a test directory:

rsync -a ~/pybin/ ~/pybin2/

I renamed some of the files in ~/pybin2.

The find...md5sum command returns the same output for both directories.

2bcf49a4d19ef9abd284311108d626f1  -

PHP-FPM doesn't write to error log

I gathered insights from a bunch of answers here and I present a comprehensive solution:

So, if you setup nginx with php5-fpm and log a message using error_log() you can see it in /var/log/nginx/error.log by default.

A problem can arise if you want to log a lot of data (say an array) using error_log(print_r($myArr, true));. If an array is large enough, it seems that nginx will truncate your log entry.

To get around this you can configure fpm ( fpm config) to manage logs. Here are the steps to do so.

  1. Open /etc/php5/fpm/pool.d/www.conf:

    $ sudo nano /etc/php5/fpm/pool.d/www.conf

  2. Uncomment the following two lines by removing ; at the beginning of the line: (error_log is defined here:

    ;php_admin_value[error_log] = /var/log/fpm-php.www.log ;php_admin_flag[log_errors] = on

  3. Create /var/log/fpm-php.www.log:

    $ sudo touch /var/log/fpm-php.www.log;

  4. Change ownership of /var/log/fpm-php.www.log so that php5-fpm can edit it:

    $ sudo chown vagrant /var/log/fpm-php.www.log

    Note: vagrant is the user that I need to give ownership to. You can see what user this should be for you by running $ ps aux | grep php.*www and looking at first column.

  5. Restart php5-fpm:

    $ sudo service php5-fpm restart

Now your logs will be in /var/log/fpm-php.www.log.

unix - count of columns in file

You could try

cat FILE | awk '{print NF}'

Send email by using codeigniter library via localhost

$insert = $this->db->insert('email_notification', $data);
                $this->session->set_flashdata("msg", "<div class='alert alert-success'> Cafe has been added Successfully.</div>");

                //require ("plugins/mailer/PHPMailerAutoload.php");
                $mail = new PHPMailer;
                $mail->SMTPOptions = array(
                    'ssl' => array(
                    'verify_peer' => false,
                    'verify_peer_name' => false,
                    'allow_self_signed' => true,

                     Your Account Has beed created successfully by Admin:
                    Username: ".$this->input->post('username')." <br><br>
                    Email: ".$this->input->post('sender_email')." <br><br>
                    <div class='background-color:#666;color:#fff;padding:6px;
                         Bookly Admin.
                $mail->isSMTP(); // Set mailer to use SMTP
                $mail->Host = ''; // Specify main and backup SMTP servers
                $mail->SMTPAuth = true; 
                $subject = "Hello  ".$this->input->post('username');
                $email = $this->input->post('sender_email'); //this email is user email
                $from_label = "Account Creation";
                $mail->Username = 'your email'; // SMTP username
                $mail->Password = 'password'; // SMTP password
                $mail->SMTPSecure = 'ssl'; // Enable TLS encryption, `ssl` also accepted
                $mail->Port = 465;
                $mail->addAddress($email, 'Bookly Admin');
                $mail->Subject = $subject;
                $mail->Body = $message;
                $mail->AltBody = 'This is the body in plain text for non-HTML mail clients';


Uninstalling Android ADT

I found a solution by myself after doing some research:

  • Go to Eclipse home folder.
  • Search for 'android' => In Windows 7 you can use search bar.
  • Delete all the file related to android, which is shown in the results.
  • Restart Eclipse.
  • Install the ADT plugin again and Restart plugin.

Now everything works fine.

What are the different NameID format used for?

About this I think you can reference to

Here're my understandings about this, with the Identity Federation Use Case to give a details for those concepts:

  • Persistent identifiers-

IdP provides the Persistent identifiers, they are used for linking to the local accounts in SPs, but they identify as the user profile for the specific service each alone. For example, the persistent identifiers are kind of like : johnForAir, jonhForCar, johnForHotel, they all just for one specified service, since it need to link to its local identity in the service.

  • Transient identifiers-

Transient identifiers are what IdP tell the SP that the users in the session have been granted to access the resource on SP, but the identities of users do not offer to SP actually. For example, The assertion just like “Anonymity(Idp doesn’t tell SP who he is) has the permission to access /resource on SP”. SP got it and let browser to access it, but still don’t know Anonymity' real name.

  • unspecified identifiers-

The explanation for it in the spec is "The interpretation of the content of the element is left to individual implementations". Which means IdP defines the real format for it, and it assumes that SP knows how to parse the format data respond from IdP. For example, IdP gives a format data "UserName=XXXXX Country=US", SP get the assertion, and can parse it and extract the UserName is "XXXXX".

How do I use the conditional operator (? :) in Ruby?

Easiest way:

param_a = 1
param_b = 2

result = param_a === param_b ? 'Same!' : 'Not same!'

since param_a is not equal to param_b then the result's value will be Not same!

Generate a random date between two other dates

Since Python 3 timedelta supports multiplication with floats, so now you can do:

import random
random_date = start + (end - start) * random.random()

given that start and end are of the type datetime.datetime. For example, to generate a random datetime within the next day:

import random
from datetime import datetime, timedelta

start =
end = start + timedelta(days=1)
random_date = start + (end - start) * random.random()

How to use subList()

I've implemented and tested this one; it should cover most bases:

public static <T> List<T> safeSubList(List<T> list, int fromIndex, int toIndex) {
    int size = list.size();
    if (fromIndex >= size || toIndex <= 0 || fromIndex >= toIndex) {
        return Collections.emptyList();

    fromIndex = Math.max(0, fromIndex);
    toIndex = Math.min(size, toIndex);

    return list.subList(fromIndex, toIndex);

How do I run Java .class files?

  1. Go to the path where you saved the java file you want to compile.
  2. Replace path by typing cmd and press enter.
  3. Command Prompt Directory will pop up containing the path file like C:/blah/blah/foldercontainJava
  4. Enter javac
  5. Press Enter. It will automatically generate java class file

Javascript Error Null is not an Object

I think the error because the elements are undefined ,so you need to add window.onload event which this event will defined your elements when the window is loaded.


    function Loaded(){
    var myButton = document.getElementById("myButton");
    var myTextfield = document.getElementById("myTextfield");

    function greetUser(userName) {
    var greeting = "Hello " + userName + "!";
    document.getElementsByTagName ("h2")[0].innerHTML = greeting;

    myButton.onclick = function() {
    var userName = myTextfield.value;

    return false;

Do you recommend using semicolons after every statement in JavaScript?

Yes, you should use semicolons after every statement in JavaScript.

Compute elapsed time

This is what I am using:

Milliseconds to a pretty format time string:

function ms2Time(ms) {
    var secs = ms / 1000;
    ms = Math.floor(ms % 1000);
    var minutes = secs / 60;
    secs = Math.floor(secs % 60);
    var hours = minutes / 60;
    minutes = Math.floor(minutes % 60);
    hours = Math.floor(hours % 24);
    return hours + ":" + minutes + ":" + secs + "." + ms;  

Get $_POST from multiple checkboxes

<input type="checkbox" name="check_list[<? echo $row['Report ID'] ?>]" value="<? echo $row['Report ID'] ?>">

And after the post, you can loop through them:

     foreach($_POST['check_list'] as $report_id){
        echo "$report_id was checked! ";

Or get a certain value posted from previous page:

  echo $report_id . " was checked!<br/>";

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

That is correct behaviour, it's up to you to create the contents for the 404 page.
The 404 header is used by spiders and download-managers to determine if the file exists.
(A page with a 404 header won't be indexed by google or other search-engines)

Normal users however don't look at http-headers and use the page as a normal page.

Reset/remove CSS styles for element only

I do not recommend using the answer that has been marked as correct here. It is a huge blob of CSS which tries to cover everything.

I would suggest that you evaluate how to remove the style from an element on a per case basis.

Lets say for SEO purposes you need to include an H1 on a page which has no actual heading in the design. You might want to make the nav link of that page an H1 but ofcourse you do not want that navigation link to display as a giant H1 on the page.

What you should do is wrap that element in an h1 tag and inspect it. See what CSS styles are being applied specifically to the h1 element.

Lets say I see the following styles applied to the element.

h1 {
    font-size: 65px;
    font-family: 'rubikbold'!important;
    font-weight: normal;
    font-style: normal;
    text-transform: uppercase;

h1, .h1 {
    font-size: 36px;

h1, .h1, h2, .h2, h3, .h3 {
    margin-top: 20px;
    margin-bottom: 10px;

h1, h2, h3, h4, h5, h6, .h1, .h2, .h3, .h4, .h5, .h6 {
    font-family: inherit;
    font-weight: 500;
    line-height: 1.1;
    color: inherit;

h1 {
    margin: .67em 0;
    font-size: 2em;

//user agent stylesheet
h1 {
    display: block;
    font-size: 2em;
    -webkit-margin-before: 0.67em;
    -webkit-margin-after: 0.67em;
    -webkit-margin-start: 0px;
    -webkit-margin-end: 0px;
    font-weight: bold;

Now you need to pin point the exact style which are applied to the H1 and unset them in a css class. This would look something like the following:

.no-style-h1 {
    font-size: unset !important;
    font-family: unset !important;
    font-weight: unset !important;
    font-style: unset !important;
    text-transform: unset !important;
    margin-top: unset !important;
    margin-bottom: unset !important;
    line-height: unset !important;
    color: unset !important;
    margin: unset !important;
    display: unset !important;
    -webkit-margin-before: unset !important;
    -webkit-margin-after: unset !important;
    -webkit-margin-start: unset !important;
    -webkit-margin-end: unset !important;

This is much cleaner and does not just dump a random blob of code into your css which you don't know what it's actually doing.

Now you can add this class to your h1

<h1 class="no-style-h1">

Php multiple delimiters in explode

You can try this solution.... It works great

function explodeX( $delimiters, $string )
    return explode( chr( 1 ), str_replace( $delimiters, chr( 1 ), $string ) );
$list = 'Thing 1&Thing 2,Thing 3|Thing 4';

$exploded = explodeX( array('&', ',', '|' ), $list );

echo '<pre>';
echo '</pre>';

Source :

Make multiple-select to adjust its height to fit options without scroll bar

friends: if you retrieve de data from a DB: you can call this $registers = *_num_rows( Result_query ) then

<select size=<?=$registers + 1; ?>"> 

Extracting just Month and Year separately from Pandas Datetime column

SINGLE LINE: Adding a column with 'year-month'-paires: ('pd.to_datetime' first changes the column dtype to date-time before the operation)

df['yyyy-mm'] = pd.to_datetime(df['ArrivalDate']).dt.strftime('%Y-%m')?

Accordingly for an extra 'year' or 'month' column:

df['yyyy'] = pd.to_datetime(df['ArrivalDate']).dt.strftime('%Y')?
df['mm'] = pd.to_datetime(df['ArrivalDate']).dt.strftime('%m')?

Regex to replace everything except numbers and a decimal point

Try this:

document.getElementById(target).value = newVal.replace(/^\d+(\.\d{0,2})?$/, "");

org.hibernate.MappingException: Unknown entity

You should call .addAnnotatedClass(Message.class) on your AnnotationConfiguration.

If you want your entities to be auto-discovered, use EntityManager (JPA)


Update: it appears you have listed the class in hibernate.cfg.xml. So auto-discovery is not necessary. Btw, try javax.persistence.Entity

How to execute a command prompt command from python

how about simply:

import os
os.system('dir c:\\')

How do I fetch multiple columns for use in a cursor loop?

Here is slightly modified version. Changes are noted as code commentary.


declare @cnt int
declare @test nvarchar(128)
-- variable to hold table name
declare @tableName nvarchar(255)
declare @cmd nvarchar(500) 
-- local means the cursor name is private to this code
-- fast_forward enables some speed optimizations
declare Tests cursor local fast_forward for

open Tests
-- Instead of fetching twice, I rather set up no-exit loop
while 1 = 1
  -- And then fetch
  fetch next from Tests into @test, @tableName
  -- And then, if no row is fetched, exit the loop
  if @@fetch_status <> 0
  -- Quotename is needed if you ever use special characters
  -- in table/column names. Spaces, reserved words etc.
  -- Other changes add apostrophes at right places.
  set @cmd = N'exec sp_rename ''' 
           + quotename(@tableName) 
           + '.' 
           + quotename(@test) 
           + N''',''' 
           + RIGHT(@test,LEN(@test)-3) 
           + '_Pct''' 
           + N', ''column''' 

  print @cmd

  EXEC sp_executeSQL @cmd

close Tests 
deallocate Tests


Java split string to array

Consider this example:

public class StringSplit {
  public static void main(String args[]) throws Exception{
    String testString = "Real|How|To|||";
    // output : [Real, How, To]

The result does not include the empty strings between the "|" separator. To keep the empty strings :

public class StringSplit {
  public static void main(String args[]) throws Exception{
    String testString = "Real|How|To|||";
       (java.util.Arrays.toString(testString.split("\\|", -1)));
    // output : [Real, How, To, , , ]

For more details go to this website:

Why is there still a row limit in Microsoft Excel?

In a word - speed. An index for up to a million rows fits in a 32-bit word, so it can be used efficiently on 32-bit processors. Function arguments that fit in a CPU register are extremely efficient, while ones that are larger require accessing memory on each function call, a far slower operation. Updating a spreadsheet can be an intensive operation involving many cell references, so speed is important. Besides, the Excel team expects that anyone dealing with more than a million rows will be using a database rather than a spreadsheet.

Read file from line 2 or skip header row

If you want to read multiple CSV files starting from line 2, this works like a charm

for files in csv_file_list:
        with open(files, 'r') as r: 
            next(r)                  #skip headers             
            rr = csv.reader(r)
            for row in rr:
                #do something

(this is part of Parfait's answer to a different question)

How to select a radio button by default?

This doesn't exactly answer the question but for anyone using AngularJS trying to achieve this, the answer is slightly different. And actually the normal answer won't work (at least it didn't for me).

Your html will look pretty similar to the normal radio button:

<input type='radio' name='group' ng-model='mValue' value='first' />First
<input type='radio' name='group' ng-model='mValue' value='second' /> Second

In your controller you'll have declared the mValue that is associated with the radio buttons. To have one of these radio buttons preselected, assign the $scope variable associated with the group to the desired input's value:


This makes the "second" radio button selected on loading the page.

EDIT: Since AngularJS 2.x

The above approach does not work if you're using version 2.x and above. Instead use ng-checked attribute as follows:

<input type='radio' name='gender' ng-model='genderValue' value='male' ng-checked='genderValue === male'/>Male
<input type='radio' name='gender' ng-model='genderValue' value='female' ng-checked='genderValue === female'/> Female

HTTPS setup in Amazon EC2

You need to register a domain(on GoDaddy for example) and put a load balancer in front of your ec2 instance - as DigaoParceiro said in his answer.

The issue is that domains generated by amazon on your ec2 instances are ephemeral. Today the domain is belonging to you, tomorrow it may not.

For that reason, let's encrypt throws an error when you try to register a certificate on amazon generated domain that states:

The ACME server refuses to issue a certificate for this domain name, because it is forbidden by policy

More details about this here:

Tools to get a pictorial function call graph of code

Our DMS Software Reengineering Toolkit has static control/dataflow/points-to/call graph analysis that has been applied to huge systems (~~25 million lines) of C code, and produced such call graphs, including functions called via function pointers.

Convert Month Number to Month Name Function in SQL

select monthname(curdate());


select monthname('2013-12-12');

How to keep form values after post

you can save them into a $_SESSION variable and then when the user calls that page again populate all the inputs with their respective session variables.

Conditional Count on a field

SELECT  Priority, COALESCE(cnt, 0)
FROM    (
        SELECT  1 AS Priority
        UNION ALL
        SELECT  2 AS Priority
        UNION ALL
        SELECT  3 AS Priority
        UNION ALL
        SELECT  4 AS Priority
        UNION ALL
        SELECT  5 AS Priority
        ) p
        SELECT  Priority, COUNT(*) AS cnt
        FROM    jobs
        GROUP BY
        ) j
ON      j.Priority = p.Priority

Can you style an html radio button to look like a checkbox?

Pure Vanilla CSS / HTML solution in 2021. It uses the CSS appearance: none; property.

Seems to be compatible with all major browsers at this time:

   appearance: none;
   border: 1px solid #d3d3d3;
   width: 30px;
   height: 30px;
   content: none;
   outline: none;
   margin: 0;
   box-shadow: rgba(0, 0, 0, 0.24) 0px 3px 8px;

input[type="radio"]:checked {
  appearance: none;
  outline: none;
  padding: 0;
  content: none;
  border: none;

  position: absolute;
  color: green !important;
  content: "\00A0\2713\00A0" !important;
  border: 1px solid #d3d3d3;
  font-weight: bolder;
  font-size: 21px;
<input type="radio" name="radio" checked>
<input type="radio" name="radio">
<input type="radio" name="radio">

Round up double to 2 decimal places

Adding to above answer if we want to format Double multiple times, we can use protocol extension of Double like below:

extension Double {
    var dollarString:String {
        return String(format: "$%.2f", self)

let a = 45.666

print(a.dollarString) //will print "$45.67"

How do you create a foreign key relationship in a SQL Server CE (Compact Edition) Database?

Visual Studio 2008 does have a designer that allows you to add FK's. Just right-click the table... Table Properties, then go to the "Add Relations" section.

How to style a checkbox using CSS

From my googling, this is the easiest way for checkbox styling. Just add :after and :checked:after CSS based on your design.

  background: #DDD;_x000D_
  margin-left: 30px;_x000D_
input[type=checkbox] {_x000D_
    cursor: pointer;_x000D_
    font-size: 17px;_x000D_
    visibility: hidden;_x000D_
    position: absolute;_x000D_
    top: 0;_x000D_
    left: 0;_x000D_
    transform: scale(1.5);_x000D_
input[type=checkbox]:after {_x000D_
    content: " ";_x000D_
    background-color: #fff;_x000D_
    display: inline-block;_x000D_
    color: #00BFF0;_x000D_
    width: 14px;_x000D_
    height: 19px;_x000D_
    visibility: visible;_x000D_
    border: 1px solid #FFF;_x000D_
    padding: 0 3px;_x000D_
    margin: 2px 0;_x000D_
    border-radius: 8px;_x000D_
    box-shadow: 0 0 15px 0 rgba(0,0,0,0.08), 0 0 2px 0 rgba(0,0,0,0.16);_x000D_
input[type=checkbox]:checked:after {_x000D_
    content: "\2714";_x000D_
    display: unset;_x000D_
    font-weight: bold;_x000D_
<input type="checkbox"> <span>Select Text</span>

Java Loop every minute

ScheduledExecutorService executor = Executors.newScheduledThreadPool(1);
executor.schedule(yourRunnable, 1L, TimeUnit.MINUTES);
// when done...

Python initializing a list of lists

The problem is that they're all the same exact list in memory. When you use the [x]*n syntax, what you get is a list of n many x objects, but they're all references to the same object. They're not distinct instances, rather, just n references to the same instance.

To make a list of 3 different lists, do this:

x = [[] for i in range(3)]

This gives you 3 separate instances of [], which is what you want

[[]]*n is similar to

l = []
x = []
for i in range(n):

While [[] for i in range(3)] is similar to:

x = []
for i in range(n):
    x.append([])   # appending a new list!

In [20]: x = [[]] * 4

In [21]: [id(i) for i in x]
Out[21]: [164363948, 164363948, 164363948, 164363948] # same id()'s for each list,i.e same object

In [22]: x=[[] for i in range(4)]

In [23]: [id(i) for i in x]
Out[23]: [164382060, 164364140, 164363628, 164381292] #different id(), i.e unique objects this time

Find duplicate records in MongoDB

    {$group: { 
            _id: {name: "$name"},
            uniqueIds: {$addToSet: "$_id"},
            count: {$sum: 1}
    {$match: { 
        count: {"$gt": 1}

First Group Query the group according to the fields.

Then we check the unique Id and count it, If count is greater then 1 then the field is duplicate in the entire collection so that thing is to be handle by $match query.

Mapping US zip code to time zone

If you want, you can also get a feel for the timezone by asking the browser Josh Fraser has a nice write up on it here

var rightNow = new Date();
var jan1 = new Date(rightNow.getFullYear(), 0, 1, 0, 0, 0, 0);
var temp = jan1.toGMTString();
var jan2 = new Date(temp.substring(0, temp.lastIndexOf(" ")-1));
var std_time_offset = (jan1 - jan2) / (1000 * 60 * 60);

The second thing that you need to know is whether the location observes daylight savings time (DST) or not. Since DST is always observed during the summer, we can compare the time offset between two dates in January, to the time offset between two dates in June. If the offsets are different, then we know that the location observes DST. If the offsets are the same, then we know that the location DOES NOT observe DST.

var june1 = new Date(rightNow.getFullYear(), 6, 1, 0, 0, 0, 0);
temp = june1.toGMTString();
var june2 = new Date(temp.substring(0, temp.lastIndexOf(" ")-1));
var daylight_time_offset = (june1 - june2) / (1000 * 60 * 60);
var dst;
if (std_time_offset == daylight_time_offset) {
    dst = "0"; // daylight savings time is NOT observed
} else {
    dst = "1"; // daylight savings time is observed

All credit for this goes to Josh Fraser.

This might help you with customers outside the US, and it might complement your zip approach.

Here is a SO questions that touch on getting the timezone from javascript

Django URL Redirect

In Django 1.8, this is how I did mine.

from django.views.generic.base import RedirectView

url(r'^$', views.comingSoon, name='homepage'),
# whatever urls you might have in here
# make sure the 'catch-all' url is placed last
url(r'^.*$', RedirectView.as_view(pattern_name='homepage', permanent=False))

Instead of using url, you can use the pattern_name, which is a bit un-DRY, and will ensure you change your url, you don't have to change the redirect too.

Calling another different view from the controller using ASP.NET MVC 4

You have to specify the name of the custom view and its related model in Controller Action method.

public ActionResult About()
   return View("NameOfViewYouWantToReturn",Model); 

How to use underscore.js as a template engine?

I wanted to share one more important finding.

use of <%= variable => would result in cross-site scripting vulnerability. So its more safe to use <%- variable -> instead.

We had to replace <%= with <%- to prevent cross-site scripting attacks. Not sure, whether this will it have any impact on the performance

set gvim font in .vimrc file

When I try:

set guifont=Consolas:h16

I get: Warning: Font "Consolas" reports bad fixed pitch metrics

and the following is work, and don't show the waring.

autocmd vimenter * GuiFont! Consolas:h16

by the way, if you want to use the mouse wheel to control the font-size, then you can add:

function! AdjustFontSize(amount)
    let s:font_size = s:font_size + a:amount
    :execute "GuiFont! Consolas:h" . s:font_size

noremap <C-ScrollWheelUp> :call AdjustFontSize(1)<CR>
noremap <C-ScrollWheelDown> :call AdjustFontSize(-1)<CR>

and if you want to pick the font, you can set

set guifont=*

will bring up a font requester, where you can pick the font you want.

enter image description here

Angular 2 ngfor first, last, index loop

By this you can get any index in *ngFor loop in ANGULAR ...

  <li *ngFor="let object of myArray; let i = index; let first = first ;let last = last;">
    <div *ngIf="first">
       // write your code...

    <div *ngIf="last">
       // write your code...

We can use these alias in *ngFor

  • index : number : let i = index to get all index of object.
  • first : boolean : let first = first to get first index of object.
  • last : boolean : let last = last to get last index of object.
  • odd : boolean : let odd = odd to get odd index of object.
  • even : boolean : let even = even to get even index of object.

How do I copy the contents of one stream to another?

There is actually, a less heavy-handed way of doing a stream copy. Take note however, that this implies that you can store the entire file in memory. Don't try and use this if you are working with files that go into the hundreds of megabytes or more, without caution.

public static void CopySmallTextStream(Stream input, Stream output)
  using (StreamReader reader = new StreamReader(input))
  using (StreamWriter writer = new StreamWriter(output))

NOTE: There may also be some issues concerning binary data and character encodings.

How do you get/set media volume (not ringtone volume) in Android?

AudioManager audio = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
int currentVolume = audio.getStreamVolume(AudioManager.STREAM_MUSIC);
int maxVolume = audio.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
float percent = 0.7f;
int seventyVolume = (int) (maxVolume*percent);
audio.setStreamVolume(AudioManager.STREAM_MUSIC, seventyVolume, 0);

How to remove the arrow from a select element in Firefox

I was having the same issue. It's easy to make it work on FF and Chrome, but on IE (8+ that we need to support) things get complicated. The easiest solution I could find for custom select elements that works "everywhere I tried", including IE8, is using .customSelect()

Submit form using AJAX and jQuery

There is a nice form plugin that allows you to send an HTML form asynchroniously.

$(document).ready(function() { 



to submit the form immediately

How do I specify the columns and rows of a multiline Editor-For in ASP.MVC?

Use TextAreaFor

@Html.TextAreaFor(model => model.Description, new { @class = "whatever-class", @cols = 80, @rows = 10 })

or use style for multi-line class.

You could also write EditorTemplate for this.

How to overlay density plots in R?

Just to provide a complete set, here's a version of Chase's answer using lattice:

dat <- data.frame(dens = c(rnorm(100), rnorm(100, 10, 5))
                   , lines = rep(c("a", "b"), each = 100))

densityplot(~dens,data=dat,groups = lines,
            plot.points = FALSE, ref = TRUE, 
            auto.key = list(space = "right"))

which produces a plot like this: enter image description here

Can I use an HTML input type "date" to collect only a year?

No you can not but you may want to use input type number as a workaround. Look at the following example:

<input type="number" min="1900" max="2099" step="1" value="2016" />

What's causing my Connection reset?

The Exception means that the socket was closed unexpectedly from the other side. Since you are calling a web service, this should not happen - most likely you're sending a request that triggers a bug in the web service.

Try logging the entire request in those cases, and see if you notice anything unusual. Otherwise, get in contact with the web service provider and send them your logged problematical request.

Regex to remove all special characters from string?

For my purposes I wanted all English ASCII chars, so this worked.

html = Regex.Replace(html, "[^\x00-\x80]+", "")

Explain the "setUp" and "tearDown" Python methods used in test cases

In general you add all prerequisite steps to setUp and all clean-up steps to tearDown.

You can read more with examples here.

When a setUp() method is defined, the test runner will run that method prior to each test. Likewise, if a tearDown() method is defined, the test runner will invoke that method after each test.

For example you have a test that requires items to exist, or certain state - so you put these actions(creating object instances, initializing db, preparing rules and so on) into the setUp.

Also as you know each test should stop in the place where it was started - this means that we have to restore app state to it's initial state - e.g close files, connections, removing newly created items, calling transactions callback and so on - all these steps are to be included into the tearDown.

So the idea is that test itself should contain only actions that to be performed on the test object to get the result, while setUp and tearDown are the methods to help you to leave your test code clean and flexible.

You can create a setUp and tearDown for a bunch of tests and define them in a parent class - so it would be easy for you to support such tests and update common preparations and clean ups.

If you are looking for an easy example please use the following link with example

Angular2 multiple router-outlet in the same template

You can not use multiple router outlets in the same template with ngIf condition. But you can use it in the way shown below:

<div *ngIf="loading">
  <span>loading true</span>
  <ng-container *ngTemplateOutlet="template"></ng-container>

<div *ngIf="!loading">
  <span>loading false</span>
  <ng-container *ngTemplateOutlet="template"></ng-container>

  <ng-template #template>
    <router-outlet> </router-outlet>

How to set the project name/group/version, plus {source,target} compatibility in the same file?

I found the solution to a similar problem. I am using Gradle 1.11 (as April, 2014). The project name can be changed directly in settings.gradle file as following:'YourNewName'

This takes care of uploading to repository (Artifactory w/ its plugin for me) with the correct artifactId.

What's the difference between process.cwd() vs __dirname?

As per node js doc process.cwd()

cwd is a method of global object process, returns a string value which is the current working directory of the Node.js process.

As per node js doc __dirname

The directory name of current script as a string value. __dirname is not actually a global but rather local to each module.

Let me explain with example,

suppose we have a main.js file resides inside C:/Project/main.js and running node main.js both these values return same file

or simply with following folder structure

+-- main.js
   +-- script.js


// C:\Project
// C:\Project
// true

suppose we have another file script.js files inside a sub directory of project ie C:/Project/lib/script.js and running node main.js which require script.js


// C:\Project
// C:\Project
// true


// C:\Project
// C:\Project\lib
// false

How to get the current user in ASP.NET MVC

If you are inside your login page, in LoginUser_LoggedIn event for instance, Current.User.Identity.Name will return an empty value, so you have to use yourLoginControlName.UserName property.

MembershipUser u = Membership.GetUser(LoginUser.UserName);

What's the difference between Apache's Mesos and Google's Kubernetes

Kubernetes is an open source project that brings 'Google style' cluster management capabilities to the world of virtual machines, or 'on the metal' scenarios. It works very well with modern operating system environments (like CoreOS or Red Hat Atomic) that offer up lightweight computing 'nodes' that are managed for you. It is written in Golang and is lightweight, modular, portable and extensible. We (the Kubernetes team) are working with a number of different technology companies (including Mesosphere who curate the Mesos open source project) to establish Kubernetes as the standard way to interact with computing clusters. The idea is to reproduce the patterns that we see people needing to build cluster applications based on our experience at Google. Some of these concepts include:

  • pods — a way to group containers together
  • replication controllers — a way to handle the lifecycle of containers
  • labels — a way to find and query containers, and
  • services — a set of containers performing a common function.

So with Kubernetes alone you will have something that is simple, easy to get up-and-running, portable and extensible that adds 'cluster' as a noun to the things that you manage in the lightest weight manner possible. Run an application on a cluster, and stop worrying about an individual machine. In this case, cluster is a flexible resource just like a VM. It is a logical computing unit. Turn it up, use it, resize it, turn it down quickly and easily.

With Mesos, there is a fair amount of overlap in terms of the basic vision, but the products are at quite different points in their lifecycle and have different sweet spots. Mesos is a distributed systems kernel that stitches together a lot of different machines into a logical computer. It was born for a world where you own a lot of physical resources to create a big static computing cluster. The great thing about it is that lots of modern scalable data processing application run well on Mesos (Hadoop, Kafka, Spark) and it is nice because you can run them all on the same basic resource pool, along with your new age container packaged apps. It is somewhat more heavy weight than the Kubernetes project, but is getting easier and easier to manage thanks to the work of folks like Mesosphere.

Now what gets really interesting is that Mesos is currently being adapted to add a lot of the Kubernetes concepts and to support the Kubernetes API. So it will be a gateway to getting more capabilities for your Kubernetes app (high availability master, more advanced scheduling semantics, ability to scale to a very large number of nodes) if you need them, and is well suited to run production workloads (Kubernetes is still in an alpha state).

When asked, I tend to say:

  1. Kubernetes is a great place to start if you are new to the clustering world; it is the quickest, easiest and lightest way to kick the tires and start experimenting with cluster oriented development. It offers a very high level of portability since it is being supported by a lot of different providers (Microsoft, IBM, Red Hat, CoreOs, MesoSphere, VMWare, etc).

  2. If you have existing workloads (Hadoop, Spark, Kafka, etc), Mesos gives you a framework that let's you interleave those workloads with each other, and mix in a some of the new stuff including Kubernetes apps.

  3. Mesos gives you an escape valve if you need capabilities that are not yet implemented by the community in the Kubernetes framework.

The ternary (conditional) operator in C

The ternary operator is a syntactic and readability convenience, not a performance shortcut. People are split on the merits of it for conditionals of varying complexity, but for short conditions, it can be useful to have a one-line expression.

Moreover, since it's an expression, as Charlie Martin wrote, that means it can appear on the right-hand side of a statement in C. This is valuable for being concise.

Reduce size of legend area in barplot

The cex parameter will do that for you.

a <- c(3, 2, 2, 2, 1, 2 )
barplot(a, beside = T,
        col = 1:6, space = c(0, 2))
       legend = c("a", "b", "c", "d", "e", "f"), 
       fill = 1:6, ncol = 2,
       cex = 0.75)

The plot

How do I import a specific version of a package using go get?

dep is the official experiment for dependency management for Go language. It requires Go 1.8 or newer to compile.

To start managing dependencies using dep, run the following command from your project's root directory:

dep init

After execution two files will be generated: Gopkg.toml ("manifest"), Gopkg.lock and necessary packages will be downloaded into vendor directory.

Let's assume that you have the project which uses package. dep will generate following files:


# Gopkg.toml example
# Refer to
# for detailed Gopkg.toml documentation.
# required = [""]
# ignored = ["", ""]
# [[constraint]]
#   name = ""
#   version = "1.0.0"
# [[constraint]]
#   name = ""
#   branch = "dev"
#   source = ""
# [[override]]
#  name = ""
#  version = "2.4.0"

  name = ""
  version = "1.2.0"


# This file is autogenerated, do not edit; changes may be undone by the next 'dep ensure'.

  name = ""
  packages = ["."]
  revision = "ea4d1f681babbce9545c9c5f3d5194a789c89f5b"
  version = "v1.2.0"

  analyzer-name = "dep"
  analyzer-version = 1
  inputs-digest = "941e8dbe52e16e8a7dff4068b7ba53ae69a5748b29fbf2bcb5df3a063ac52261"
  solver-name = "gps-cdcl"
  solver-version = 1

There are commands which help you to update/delete/etc packages, please find more info on official github repo of dep (dependency management tool for Go).

Laravel password validation rule

This doesn't quite match the OP requirements, though hopefully it helps. With Laravel you can define your rules in an easy-to-maintain format like so:

    $inputs = [
        'email'    => 'foo',
        'password' => 'bar',

    $rules = [
        'email'    => 'required|email',
        'password' => [
            'min:10',             // must be at least 10 characters in length
            'regex:/[a-z]/',      // must contain at least one lowercase letter
            'regex:/[A-Z]/',      // must contain at least one uppercase letter
            'regex:/[0-9]/',      // must contain at least one digit
            'regex:/[@$!%*#?&]/', // must contain a special character

    $validation = \Validator::make( $inputs, $rules );

    if ( $validation->fails() ) {
        print_r( $validation->errors()->all() );

Would output:

        'The email must be a valid email address.',
        'The password must be at least 10 characters.',
        'The password format is invalid.',

(The regex rules share an error message by default—i.e. four failing regex rules result in one error message)

Convert Xml to Table SQL Server

This is the answer, hope it helps someone :)

First there are two variations on how the xml can be written:




       Tbl.Col.value('IdInvernadero[1]', 'smallint'),  
       Tbl.Col.value('IdProducto[1]', 'smallint'),  
       Tbl.Col.value('IdCaracteristica1[1]', 'smallint'),
       Tbl.Col.value('IdCaracteristica2[1]', 'smallint'),
       Tbl.Col.value('Cantidad[1]', 'int'),
       Tbl.Col.value('Folio[1]', 'varchar(7)')
FROM   @xml.nodes('//row') Tbl(Col)  


<row IdInvernadero="8" IdProducto="3" IdCaracteristica1="8" IdCaracteristica2="8" Cantidad ="25" Folio="4568457" />                         
<row IdInvernadero="3" IdProducto="3" IdCaracteristica1="1" IdCaracteristica2="2" Cantidad ="72" Folio="4568457" />


       Tbl.Col.value('@IdInvernadero', 'smallint'),  
       Tbl.Col.value('@IdProducto', 'smallint'),  
       Tbl.Col.value('@IdCaracteristica1', 'smallint'),
       Tbl.Col.value('@IdCaracteristica2', 'smallint'),
       Tbl.Col.value('@Cantidad', 'int'),
       Tbl.Col.value('@Folio', 'varchar(7)')

FROM   @xml.nodes('//row') Tbl(Col)

Taken from:



Filtering DataSet

The above were really close. Here's my solution:

Private Sub getDsClone(ByRef inClone As DataSet, ByVal matchStr As String, ByRef outClone As DataSet)
    Dim i As Integer

    outClone = inClone.Clone
    Dim dv As DataView = inClone.Tables(0).DefaultView
    dv.RowFilter = matchStr
    Dim dt As New DataTable
    dt = dv.ToTable
    For i = 0 To dv.Count - 1
End Sub

java.lang.ClassNotFoundException: sun.jdbc.odbc.JdbcOdbcDriver Exception occurring. Why?

in JDK 8, jdbc odbc bridge is no longer used and thus removed fro the JDK. to use Microsoft Access database in JAVA, you need 5 extra JAR libraries.

1- hsqldb.jar

2- jackcess 2.0.4.jar

3- commons-lang-2.6.jar

4- commons-logging-1.1.1.jar

5- ucanaccess-2.0.8.jar

add these libraries to your java project and start with following lines.

Connection conn=DriverManager.getConnection("jdbc:ucanaccess://<Path to your database i.e. MS Access DB>");
Statement s = conn.createStatement();

path could be like E:/Project/JAVA/DBApp

and then your query to be executed. Like

ResultSet rs = s.executeQuery("SELECT * FROM Course");
    System.out.println(rs.getString("Title") + " " + rs.getString("Code") + " " + rs.getString("Credits"));

certain imports to be used. try catch block must be used and some necessary things no to be forgotten.

Remember, no need of bridging drivers like jdbc odbc or any stuff.

Excel - Using COUNTIF/COUNTIFS across multiple sheets/same column

This could be solved without VBA by the following technique.

In this example I am counting all the threes (3) in the range A:A of the sheets Page M904, Page M905 and Page M906.

List all the sheet names in a single continuous range like in the following example. Here listed in the range D3:D5.

enter image description here

Then by having the lookup value in cell B2, the result can be found in cell B4 by using the following formula:


How do I set the selected item in a comboBox to match my string using C#?

All methods, tricks, and lines of code setting ComboBox item will not work until the ComboBox has a parent.

JQuery .each() backwards

You can also try

var arr = []$('li'))
arr.each(function(){ ... })

Resolving require paths with webpack

If you're using create-react-app, you can simply add a .env file containing



How to define object in array in Mongoose schema correctly with 2d geo index

You can declare trk by the following ways : - either

trk : [{
    lat : String,
    lng : String


trk : { type : Array , "default" : [] }

In the second case during insertion make the object and push it into the array like

db.update({'Searching criteria goes here'},
 $push : {
    trk :  {
             "lat": 50.3293714,
             "lng": 6.9389939
           } //inserted data is the object to be inserted 

or you can set the Array of object by

db.update ({'seraching criteria goes here ' },
 $set : {
          trk : [ {
                     "lat": 50.3293714,
                     "lng": 6.9389939
                     "lat": 50.3293284,
                     "lng": 6.9389634
               ]//'inserted Array containing the list of object'

Resolving PKIX path building failed Error?

It is possible to disable SSL verification programmatically. Works in a pinch for dev, but not recommended for production since you'll want to either use "real" SSL verification there or install and use your own trusted keys and then still use "real" SSL verification.

Below code works for me:



public class TrustAnyTrustManager implements X509TrustManager {

  public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {

  public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {

  public X509Certificate[] getAcceptedIssuers() {
    return null;

             HttpsURLConnection conn = null;
             URL url = new URL(serviceUrl);
             conn = (HttpsURLConnection) url.openConnection();
             SSLContext sc = SSLContext.getInstance("SSL");  
             sc.init(null, new TrustManager[]{new TrustAnyTrustManager()}, new;  
                    // Create all-trusting host name verifier
             HostnameVerifier allHostsValid = new HostnameVerifier() {
               public boolean verify(String hostname, SSLSession session) {
                return true;

Or if you don't control the Connections underneath, you can also override SSL verification globally for all connections

If you are using Apache HTTPClient you must disable it "differently" (sadly):

Change the color of a bullet in a html list?

Wrap the text within the list item with a span (or some other element) and apply the bullet color to the list item and the text color to the span.

The database cannot be opened because it is version 782. This server supports version 706 and earlier. A downgrade path is not supported

For me using solution provided by codedom did not worked. Here we can only changed compatibility version of exiting database.

But actual problem lies that, internal database version which do not matches due to changes in there storage format.

Check out more details about SQL Server version and their internal db version & Db compatibility level here So it would be good if you create your database using SQL Server 2012 Express version or below. Or start using Visual Studio 2015 Preview.

What is the maximum length of a URL in different browsers?

It seems that Chrome at least has raised this limit. I pasted 20,000 characters into the bookmarklet and it took it.

show and hide divs based on radio button click

You were pretty close. You're description div tags didn't have the .desc class defined. For your scenario you should have the radio button value equal to the div that you're trying to show.


<div id="myRadioGroup">

    2 Cars<input type="radio" name="cars" checked="checked" value="twoCarDiv"  />

    3 Cars<input type="radio" name="cars" value="threeCarDiv" />

    <div id="twoCarDiv" class="desc">
        2 Cars Selected
    <div id="threeCarDiv" class="desc">
        3 Cars Selected


$(document).ready(function() {
    $("input[name$='cars']").click(function() {
        var test = $(this).val();
        $("#" + test).show();

working example:

Binding ConverterParameter

No, unfortunately this will not be possible because ConverterParameter is not a DependencyProperty so you won't be able to use bindings

But perhaps you could cheat and use a MultiBinding with IMultiValueConverter to pass in the 2 Tag properties.

Change the name of a key in dictionary

I haven't seen this exact answer:

dict['key'] = value

You can even do this to object attributes. Make them into a dictionary by doing this:

dict = vars(obj)

Then you can manipulate the object attributes like you would a dictionary:

dict['attribute'] = value

PHP how to get local IP of system

A reliable way to get the external IP address of the local machine would be to query the routing table, although we have no direct way to do it in PHP.

However we can get the system to do it for us by binding a UDP socket to a public address, and getting its address:

$sock = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
socket_connect($sock, "", 53);
socket_getsockname($sock, $name); // $name passed by reference

// This is the local machine's external IP address
$localAddr = $name;

socket_connect will not cause any network traffic because it's an UDP socket.

Java : Cannot format given Object as a Date

SimpleDateFormat.format(...) takes a Date as parameter and format Date to String. So you need have a look API carefully

c# - approach for saving user settings in a WPF application?

I wanted to use an xml control file based on a class for my desktop WPF application. The above code to do this all in one is excellent and set me in the right direction. In case anyone is searching for a solution here is the class I built:

Imports System.IO
Imports System.Xml.Serialization

Public Class XControl

Private _person_ID As Integer
Private _person_UID As Guid

'load from file
Public Function XCRead(filename As String) As XControl
    Using sr As StreamReader = New StreamReader(filename)
        Dim xmls As New XmlSerializer(GetType(XControl))
        Return CType(xmls.Deserialize(sr), XControl)
    End Using
End Function

'save to file
Public Sub XCSave(filename As String)
    Using sw As StreamWriter = New StreamWriter(filename)
        Dim xmls As New XmlSerializer(GetType(XControl))
        xmls.Serialize(sw, Me)
    End Using
End Sub

'all the get/set is below here

Public Property Person_ID() As Integer
        Return _person_ID
    End Get
    Set(value As Integer)
        _person_ID = value
    End Set
End Property

Public Property Person_UID As Guid
        Return _person_UID
    End Get
    Set(value As Guid)
        _person_UID = value
    End Set
End Property

End Class

Rounding integer division (instead of truncating)

int a, b;
int c = a / b;
if(a % b) { c++; }

Checking if there is a remainder allows you to manually roundup the quotient of integer division.

What is the maximum length of a valid email address?


And the segments look like this


64 + 1 + 255 = 320

You should also read this if you are validating emails

Simulating a click in jQuery/JavaScript on a link

Try this

function submitRequest(buttonId) {
    if (document.getElementById(buttonId) == null
            || document.getElementById(buttonId) == undefined) {
    if (document.getElementById(buttonId).dispatchEvent) {
        var e = document.createEvent("MouseEvents");
        e.initEvent("click", true, true);
    } else {

and you can use it like


Left function in c#

It sounds like you're asking about a function

string Left(string s, int left)

that will return the leftmost left characters of the string s. In that case you can just use String.Substring. You can write this as an extension method:

public static class StringExtensions
    public static string Left(this string value, int maxLength)
        if (string.IsNullOrEmpty(value)) return value;
        maxLength = Math.Abs(maxLength);

        return ( value.Length <= maxLength 
               ? value 
               : value.Substring(0, maxLength)

and use it like so:

string left = s.Left(number);

For your specific example:

string s = fac.GetCachedValue("Auto Print Clinical Warnings").ToLower() + " ";
string left = s.Substring(0, 1);

How to get the client IP address in PHP

Try this one:


How to check in Javascript if one element is contained within another

try this one:

x = document.getElementById("td35");
if (x.childElementCount > 0) {
    x = document.getElementById("LastRow"); = "block";
else {
    x = document.getElementById("LastRow"); = "none";

Remove element of a regular array

Here's how I did it...

    public static ElementDefinitionImpl[] RemoveElementDefAt(
        ElementDefinition[] oldList,
        int removeIndex
        ElementDefinitionImpl[] newElementDefList = new ElementDefinitionImpl[ oldList.Length - 1 ];

        int offset = 0;
        for ( int index = 0; index < oldList.Length; index++ )
            ElementDefinitionImpl elementDef = oldList[ index ] as ElementDefinitionImpl;
            if ( index == removeIndex )
                //  This is the one we want to remove, so we won't copy it.  But 
                //  every subsequent elementDef will by shifted down by one.
                offset = -1;
                newElementDefList[ index + offset ] = elementDef;
        return newElementDefList;

phpinfo() is not working on my CentOS server

It happened to me as well. On a newly provisioned Red Hat Linux 7 server.

When I run a PHP page, i.e. info.php, I could see plain text PHP scripts instead of executing them.

I just installed PHP:

[root@localhost ~]# yum install php

And then restarted Apache HTTP Server:

[root@localhost ~]# systemctl restart httpd

What are "res" and "req" parameters in Express functions?

I noticed one error in Dave Ward's answer (perhaps a recent change?): The query string paramaters are in request.query, not request.params. (See )

request.params by default is filled with the value of any "component matches" in routes, i.e.

app.get('/user/:id', function(request, response){
  response.send('user ' +;

and, if you have configured express to use its bodyparser (app.use(express.bodyParser());) also with POST'ed formdata. (See How to retrieve POST query parameters? )

Two Divs next to each other, that then stack with responsive change

With a mediaquery based on a min-width you could achieve something like


.wrapper { 
  border : 2px dotted #ccc; padding: 2px; 

.wrapper div {
   width: 100%; 
   min-height: 200px;
   padding: 10px;
   -webkit-box-sizing: border-box;
   -moz-box-sizing: border-box;
   box-sizing: border-box;
#one { background-color: gray; }
#two { background-color: white; }

@media screen and (min-width: 600px) {
   .wrapper {
      height: auto; overflow: hidden; // clearing 
   #one { width: 200px; float: left; }
   #two { margin-left: 200px; }

In my example the breakpoint is 600px but you could adapt it to your needs.

How can I scroll up more (increase the scroll buffer) in iTerm2?

macOS default termianl

macOS 10.15.7

  1. open Terminal
  2. click Prefrences...
  3. select Window tab
  4. just change Scrollback to Limit number of rows to: what your wanted.

my screenshots

enter image description here

enter image description here

enter image description here

Column order manipulation using col-lg-push and col-lg-pull in Twitter Bootstrap 3

This answer is in three parts, see below for the official release (v3 and v4)

I couldn't even find the col-lg-push-x or pull classes in the original files for RC1 i downloaded, so check your bootstrap.css file. hopefully this is something they will sort out in RC2.

anyways, the col-push-* and pull classes did exist and this will suit your needs. Here is a demo

<div class="row">
    <div class="col-sm-5 col-push-5">
        Content B
    <div class="col-sm-5 col-pull-5">
        Content A
    <div class="col-sm-2">
        Content C


Also see This blog post on the subject

  • col-vp-push-x = push the column to the right by x number of columns, starting from where the column would normally render -> position: relative, on a vp or larger view-port.

  • col-vp-pull-x = pull the column to the left by x number of columns, starting from where the column would normally render -> position: relative, on a vp or larger view-port.

    vp = xs, sm, md, or lg

    x = 1 thru 12

I think what messes most people up, is that you need to change the order of the columns in your HTML markup (in the example below, B comes before A), and that it only does the pushing or pulling on view-ports that are greater than or equal to what was specified. i.e. col-sm-push-5 will only push 5 columns on sm view-ports or greater. This is because Bootstrap is a "mobile first" framework, so your HTML should reflect the mobile version of your site. The Pushing and Pulling are then done on the larger screens.

  • (Desktop) Larger view-ports get pushed and pulled.
  • (Mobile) Smaller view-ports render in normal order.


<div class="row">
    <div class="col-sm-5 col-sm-push-5">
        Content B
    <div class="col-sm-5 col-sm-pull-5">
        Content A
    <div class="col-sm-2">
        Content C

View-port >= sm


View-port < sm



With v4 comes flexbox and other changes to the grid system and the push\pull classes have been removed in favor of using flexbox ordering.

  • Use .order-* classes to control visual order (where * = 1 thru 12)
  • This can also be grid tier specific .order-md-*
  • Also .order-first (-1) and .order-last (13) avalable

<div class="row">_x000D_
  <div class="col order-2">1st yet 2nd</div>_x000D_
  <div class="col order-1">2nd yet 1st</div>_x000D_

How to update a single pod without touching other dependencies

Just a small notice.

pod update POD_NAME

will work only if this pod was already installed. Otherwise you will have to update all of them with

pod update


Soft hyphen in HTML (<wbr> vs. &shy;)

There is an ongoing effort to standardize hyphenation in CSS3.

Some modern browsers, notably Safari and Firefox, already support this. Here is a good and up to date reference on browser support.

Once the CSS hyphenation gets implemented universally, that would be the best solution. In the meantime, I can recommend Hyphenator - a JS script that figures out how to hyphenate your text in the way most appropriate for a particular browser.


  • relies on Franklin M. Liangs hyphenation algorithm, commonly known from LaTeX and OpenOffice.
  • uses CSS3 hyphenation where it is available,
  • automatically inserts &shy; on most other browsers,
  • supports multiple languages,
  • is highly configurable,
  • gracefully falls back in case javascript is not enabled.

I've used it and it works great!

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

Your data.frame mat is rectangular (n_rows!= n_cols).

Therefore, you cannot make a data.frame out of the column- and rownames, because each column in a data.frame must be the same length.

Maybe this suffices your needs:

mat$id <- rownames(mat) 

IE throws JavaScript Error: The value of the property 'googleMapsQuery' is null or undefined, not a Function object (works in other browsers)

So I had a similar situation with the same error. I forgot I changed the compatibility mode on my dev machine and I had a console.log command in my javascript as well. I changed compatibility mode back in IE, and removed the console.log command. No more issue.

How do I consume the JSON POST data in an Express application

I think you're conflating the use of the response object with that of the request.

The response object is for sending the HTTP response back to the calling client, whereas you are wanting to access the body of the request. See this answer which provides some guidance.

If you are using valid JSON and are POSTing it with Content-Type: application/json, then you can use the bodyParser middleware to parse the request body and place the result in request.body of your route.

For earlier versions of Express (< 4)

var express = require('express')
  , app = express.createServer();

app.use(express.bodyParser());'/', function(request, response){
  console.log(request.body);      // your JSON
  response.send(request.body);    // echo the result back


Test along the lines of:

$ curl -d '{"MyKey":"My Value"}' -H "Content-Type: application/json"
{"MyKey":"My Value"}

Updated for Express 4+

Body parser was split out into it's own npm package after v4, requires a separate install npm install body-parser

var express = require('express')
  , bodyParser = require('body-parser');

var app = express();

app.use(bodyParser.json());'/', function(request, response){
  console.log(request.body);      // your JSON
   response.send(request.body);    // echo the result back


Update for Express 4.16+

Starting with release 4.16.0, a new express.json() middleware is available.

var express = require('express');

var app = express();

app.use(express.json());'/', function(request, response){
  console.log(request.body);      // your JSON
   response.send(request.body);    // echo the result back


return query based on date

Find with a specific date:

db.getCollection('CollectionName').find({"DepartureDate" : new ISODate("2019-06-21T00:00:00.000Z")})

Find with greater gte or little lt :

db.getCollection('CollectionName').find({"DepartureDate" : { $gte : new ISODate("2019-06-11T00:00:00.000Z") }})

Find by range:

    "DepartureDate": { 
        $lt: new Date(), 
        $gte: new Date(new Date().setDate(new Date().getDate()-15))

What does '--set-upstream' do?

When you push to a remote and you use the --set-upstream flag git sets the branch you are pushing to as the remote tracking branch of the branch you are pushing.

Adding a remote tracking branch means that git then knows what you want to do when you git fetch, git pull or git push in future. It assumes that you want to keep the local branch and the remote branch it is tracking in sync and does the appropriate thing to achieve this.

You could achieve the same thing with git branch --set-upstream-to or git checkout --track. See the git help pages on tracking branches for more information.

Flatten list of lists

I would use itertools.chain - this will also cater for > 1 element in each sublist:

from itertools import chain
list(chain.from_iterable([[180.0], [173.8], [164.2], [156.5], [147.2], [138.2]]))

Assigning out/ref parameters in Moq

For 'out', the following seems to work for me.

public interface IService
    void DoSomething(out string a);

public void Test()
    var service = new Mock<IService>();
    var expectedValue = "value";
    service.Setup(s => s.DoSomething(out expectedValue));

    string actualValue;
    service.Object.DoSomething(out actualValue);
    Assert.AreEqual(expectedValue, actualValue);

I'm guessing that Moq looks at the value of 'expectedValue' when you call Setup and remembers it.

For ref, I'm looking for an answer also.

I found the following QuickStart guide useful:

How to edit a JavaScript alert box title?

You can do this in IE:

<script language="VBScript">
Sub myAlert(title, content)
      MsgBox content, 0, title
End Sub

<script type="text/javascript">
myAlert("My custom title", "Some content");

(Although, I really wish you couldn't.)

How to set a header for a HTTP GET request, and trigger file download?

Pure jQuery.

  type: "GET",
  url: "",
  headers: {
    'Authorization': 'Bearer eyJraWQiFUDA.......TZxX1MGDGyg'
  xhrFields: {
    responseType: 'blob'
  success: function (blob) {
    var windowUrl = window.URL || window.webkitURL;
    var url = windowUrl.createObjectURL(blob);
    var anchor = document.createElement('a');
    anchor.href = url; = '';;
  error: function (error) {

How to select current date in Hive SQL

According to the LanguageManual, you can use unix_timestamp() to get the "current time stamp using the default time zone." If you need to convert that to something more human-readable, you can use from_unixtime(unix_timestamp()).

Hope that helps.

How to set Grid row and column positions programmatically

For attached properties you can either call SetValue on the object for which you want to assign the value:

tblock.SetValue(Grid.RowProperty, 4);

Or call the static Set method (not as an instance method like you tried) for the property on the owner type, in this case SetRow:

Grid.SetRow(tblock, 4);

Moving x-axis to the top of a plot in matplotlib

tick_params is very useful for setting tick properties. Labels can be moved to the top with:


Change bundle identifier in Xcode when submitting my first app in IOS

Just edit the Project name by single click on the Top of project navigator window, will work in this case. You need not to try any other thing. :)

Center Oversized Image in Div

It's simple with some flex and overflow set to hidden.

enter image description here

<!DOCTYPE html>
<html lang="en">
        div {
            height: 150px;
            width: 150px;
            border: 2px solid red;
            overflow: hidden;
            display: flex;
            align-items: center;
            justify-content: center;
        <img src="sun.jpg" alt="">

Pass array to mvc Action via AJAX

I work with core 2.2 and jquery and have to submit a complex object ('main class') from a view to a controller with simple data fields and some array's.
As soon as I have added the array in the c# 'main class' definition (see below) and submitted the (correct filled) array over ajax (post), the whole object was null in the controller.
First, I thought, the missing "traditional: true," to my ajax call was the reason, but this is not the case.
In my case the reason was the definition in the c# 'main class'.
In the 'main class', I had:

public List<EreignisTagNeu> oEreignistageNeu { get; set; }

and EreignisTagNeu was defined as:

public class EreignisTagNeu
 public int iHME_Key { get; set; } 

I had to change the definition in the 'main class' to:

 public List<int> oEreignistageNeu { get; set; }

Now it works.
So... for me it seems as core has a problem (with post), if the list for an array is not defined completely in the 'main class'.
Note: In my case this works with or without "traditional: true," to the ajax call

Performance of Arrays vs. Lists

Since I had a similar question this got me a fast start.

My question is a bit more specific, 'what is the fastest method for a reflexive array implementation'

The testing done by Marc Gravell shows a lot, but not exactly access timing. His timing include the looping over the array's and lists as well. Since I also came up with a third method that I wanted to test, a 'Dictionary', just to compare, I extended hist test code.

Firts, I do a test using a constant, which gives me a certain timing including the loop. This is a 'bare' timing, excluding the actual access. Then I do a test with accessing the subject structure, this gives me and 'overhead included' timing, looping and actual access.

The difference between 'bare' timing and 'overhead indluded' timing gives me an indication of the 'structure access' timing.

But how accurate is this timing? During the test windows will do some time slicing for shure. I have no information about the time slicing but I asume it is evenly distributed during the test and in the order of tens of msec which means that the accuracy for the timing should be in the order of +/- 100 msec or so. A bit rough estimate? Anyway a source of a systematic mearure error.

Also, the tests were done in 'Debug' mode with no optimalisation. Otherwise the compiler might change the actual test code.

So, I get two results, one for a constant, marked '(c)', and one for access marked '(n)' and the difference 'dt' tells me how much time the actual access takes.

And this are the results:

          Dictionary(c)/for: 1205ms (600000000)
          Dictionary(n)/for: 8046ms (589725196)
 dt = 6841

                List(c)/for: 1186ms (1189725196)
                List(n)/for: 2475ms (1779450392)
 dt = 1289

               Array(c)/for: 1019ms (600000000)
               Array(n)/for: 1266ms (589725196)
 dt = 247

 Dictionary[key](c)/foreach: 2738ms (600000000)
 Dictionary[key](n)/foreach: 10017ms (589725196)
 dt = 7279

            List(c)/foreach: 2480ms (600000000)
            List(n)/foreach: 2658ms (589725196)
 dt = 178

           Array(c)/foreach: 1300ms (600000000)
           Array(n)/foreach: 1592ms (589725196)
 dt = 292

 dt +/-.1 sec   for    foreach
 Dictionary     6.8       7.3
 List           1.3       0.2
 Array          0.2       0.3

 Same test, different system:
 dt +/- .1 sec  for    foreach
 Dictionary     14.4   12.0
       List      1.7    0.1
      Array      0.5    0.7

With better estimates on the timing errors (how to remove the systematic measurement error due to time slicing?) more could be said about the results.

It looks like List/foreach has the fastest access but the overhead is killing it.

The difference between List/for and List/foreach is stange. Maybe some cashing is involved?

Further, for access to an array it does not matter if you use a for loop or a foreach loop. The timing results and its accuracity makes the results 'comparible'.

Using a dictionary is by far the slowest, I only considered it because on the left side (the indexer) I have a sparse list of integers and not a range as is used in this tests.

Here is the modified test code.

Dictionary<int, int> dict = new Dictionary<int, int>(6000000);
List<int> list = new List<int>(6000000);
Random rand = new Random(12345);
for (int i = 0; i < 6000000; i++)
    int n = rand.Next(5000);
    dict.Add(i, n);
int[] arr = list.ToArray();

int chk = 0;
Stopwatch watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    int len = dict.Count;
    for (int i = 0; i < len; i++)
        chk += 1; // dict[i];
long c_dt = watch.ElapsedMilliseconds;
Console.WriteLine("         Dictionary(c)/for: {0}ms ({1})", c_dt, chk);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    int len = dict.Count;
    for (int i = 0; i < len; i++)
        chk += dict[i];
long n_dt = watch.ElapsedMilliseconds;
Console.WriteLine("         Dictionary(n)/for: {0}ms ({1})", n_dt, chk);
Console.WriteLine("dt = {0}", n_dt - c_dt);

watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    int len = list.Count;
    for (int i = 0; i < len; i++)
        chk += 1; // list[i];
c_dt = watch.ElapsedMilliseconds;
Console.WriteLine("               List(c)/for: {0}ms ({1})", c_dt, chk);

watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    int len = list.Count;
    for (int i = 0; i < len; i++)
        chk += list[i];
n_dt = watch.ElapsedMilliseconds;
Console.WriteLine("               List(n)/for: {0}ms ({1})", n_dt, chk);
Console.WriteLine("dt = {0}", n_dt - c_dt);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    for (int i = 0; i < arr.Length; i++)
        chk += 1; // arr[i];
c_dt = watch.ElapsedMilliseconds;
Console.WriteLine("              Array(c)/for: {0}ms ({1})", c_dt, chk);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    for (int i = 0; i < arr.Length; i++)
        chk += arr[i];
n_dt = watch.ElapsedMilliseconds;
Console.WriteLine("Array(n)/for: {0}ms ({1})", n_dt, chk);
Console.WriteLine("dt = {0}", n_dt - c_dt);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    foreach (int i in dict.Keys)
        chk += 1; // dict[i]; ;
c_dt = watch.ElapsedMilliseconds;
Console.WriteLine("Dictionary[key](c)/foreach: {0}ms ({1})", c_dt, chk);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    foreach (int i in dict.Keys)
        chk += dict[i]; ;
n_dt = watch.ElapsedMilliseconds;
Console.WriteLine("Dictionary[key](n)/foreach: {0}ms ({1})", n_dt, chk);
Console.WriteLine("dt = {0}", n_dt - c_dt);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    foreach (int i in list)
        chk += 1; // i;
c_dt = watch.ElapsedMilliseconds;
Console.WriteLine("           List(c)/foreach: {0}ms ({1})", c_dt, chk);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    foreach (int i in list)
        chk += i;
n_dt = watch.ElapsedMilliseconds;
Console.WriteLine("           List(n)/foreach: {0}ms ({1})", n_dt, chk);
Console.WriteLine("dt = {0}", n_dt - c_dt);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    foreach (int i in arr)
        chk += 1; // i;
c_dt = watch.ElapsedMilliseconds;
Console.WriteLine("          Array(c)/foreach: {0}ms ({1})", c_dt, chk);

chk = 0;
watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
    foreach (int i in arr)
        chk += i;
n_dt = watch.ElapsedMilliseconds;
Console.WriteLine("Array(n)/foreach: {0}ms ({1})", n_dt, chk);
Console.WriteLine("dt = {0}", n_dt - c_dt);

Interfaces — What's the point?

No one has really explained in plain terms how interfaces are useful, so I'm going to give it a shot (and steal an idea from Shamim's answer a bit).

Lets take the idea of a pizza ordering service. You can have multiple types of pizzas and a common action for each pizza is preparing the order in the system. Each pizza has to be prepared but each pizza is prepared differently. For example, when a stuffed crust pizza is ordered the system probably has to verify certain ingredients are available at the restaurant and set those aside that aren't needed for deep dish pizzas.

When writing this in code, technically you could just do

public class Pizza()
    public void Prepare(PizzaType tp)
        switch (tp)
            case PizzaType.StuffedCrust:
                // prepare stuffed crust ingredients in system

            case PizzaType.DeepDish:
                // prepare deep dish ingredients in system

            //.... etc.

However, deep dish pizzas (in C# terms) may require different properties to be set in the Prepare() method than stuffed crust, and thus you end up with a lot of optional properties, and the class doesn't scale well (what if you add new pizza types).

The proper way to solve this is to use interface. The interface declares that all Pizzas can be prepared, but each pizza can be prepared differently. So if you have the following interfaces:

public interface IPizza
    void Prepare();

public class StuffedCrustPizza : IPizza
    public void Prepare()
        // Set settings in system for stuffed crust preparations

public class DeepDishPizza : IPizza
    public void Prepare()
        // Set settings in system for deep dish preparations

Now your order handling code does not need to know exactly what types of pizzas were ordered in order to handle the ingredients. It just has:

public PreparePizzas(IList<IPizza> pizzas)
    foreach (IPizza pizza in pizzas)

Even though each type of pizza is prepared differently, this part of the code doesn't have to care what type of pizza we are dealing with, it just knows that it's being called for pizzas and therefore each call to Prepare will automatically prepare each pizza correctly based on its type, even if the collection has multiple types of pizzas.

JQuery: dynamic height() with window resize()

I feel like there should be a no javascript solution, but how is this?

$(window).resize(function() {
    $('#content').height($(window).height() - 46);


Composer Warning: openssl extension is missing. How to enable in WAMP

WAMP uses different php.ini files in the CLI and for Apache. when you enable php_openssl through the WAMP UI, you enable it for Apache, not for the CLI. You need to modify C:\wamp\bin\php\php-5.4.3\php.ini to enable it for the CLI.

How to print values separated by spaces instead of new lines in Python 2.7

First of all print isn't a function in Python 2, it is a statement.

To suppress the automatic newline add a trailing ,(comma). Now a space will be used instead of a newline.


print 1,
print 2


1 2

Or use Python 3's print() function:

from __future__ import print_function
print(1, end=' ') # default value of `end` is '\n'

As you can clearly see print() function is much more powerful as we can specify any string to be used as end rather a fixed space.

How to subtract hours from a date in Oracle so it affects the day also

you should divide hours by 24 not 11
like this:
select to_char(sysdate - 2/24, 'dd-mon-yyyy HH24') from dual

How to select element using XPATH syntax on Selenium for Python?


<div id='a'>
    <a class='click'>abc</a>

You could use the XPATH as :



<a class="click">abc</a>

That said your Python code should be as :


How can I open two pages from a single click without using JavaScript?

Without JavaScript, it's not possible to open two pages by clicking one link unless both pages are framed on the one page that opens from clicking the link. With JS it's trivial:

<p><a href="#" onclick="'');'');">Click to open Google and Yahoo</a></p>

Do note that this will be blocked by popup blockers built into web browsers but you are usually notified of this.

Google maps API V3 method fitBounds()

This happens because LatLngBounds() does not take two arbitrary points as parameters, but SW and NE points

use the .extend() method on an empty bounds object

var bounds = new google.maps.LatLngBounds();

Demo at

Div show/hide media query

It sounds like you may be wanting to access the viewport of the device. You can do this by inserting this meta tag in your header.

<meta name="viewport" content="width=device-width, initial-scale=1.0">

Best method to download image from url in Android

Add This Dependency For Android Networking Into Your Project

compile ''

    String url = "";
    File file;
    String dirPath, fileName;
    Button downldImg;

    protected void onCreate(Bundle savedInstanceState) {

        // Initialization Of DownLoad Button
        downldImg = (Button) findViewById(;

        // Initialization Of DownLoad Button

        //Folder Creating Into Phone Storage
        dirPath = Environment.getExternalStorageDirectory() + "/Image";

        fileName = "image.jpeg";

        //file Creating With Folder & Fle Name
        file = new File(dirPath, fileName);

        //Click Listener For DownLoad Button
        downldImg.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {

      , dirPath, fileName)
                        .startDownload(new DownloadListener() {
                            public void onDownloadComplete() {

                                Toast.makeText(MainActivity.this, "DownLoad Complete", Toast.LENGTH_SHORT).show();

                            public void onError(ANError anError) {


After Run This Code Check Your Phone Memory You Can See There A Folder - Image Check Inside This Folder , You see There a Image File with name of "image.jpeg"

Thank You !!!

C++ callback using class member

A complete working example from the code above.... for C++11:

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

#if __cplusplus <= 199711L
  #error This file needs at least a C++11 compliant compiler, try using:
  #error    $ g++ -std=c++11 ..

using namespace std;

class EventHandler {
        void addHandler(std::function<void(int)> callback) {
            printf("\nHandler added...");
            // Let's pretend an event just occured

class MyClass
        // Note: No longer marked `static`, and only takes the actual argument
        void Callback(int x);

        EventHandler *pHandler;
        int private_x;

MyClass::MyClass(int value) {
    using namespace std::placeholders; // for `_1`

    pHandler = new EventHandler();
    private_x = value;
    pHandler->addHandler(std::bind(&MyClass::Callback, this, _1));

void MyClass::Callback(int x) {
    // No longer needs an explicit `instance` argument,
    // as `this` is set up properly
    printf("\nResult:%d\n\n", (x+private_x));

// Main method
int main(int argc, char const *argv[]) {

    printf("\nCompiler:%ld\n", __cplusplus);
    new MyClass(5);
    return 0;

// where $1 is your .cpp file name... this is the command used:
// g++ -std=c++11 -Wall -o $1 $1.cpp
// chmod 700 $1
// ./$1

Output should be:


Handler added...

Large Numbers in Java

Checkout BigDecimal and BigInteger.

Interview Question: Merge two sorted singly linked lists without creating new nodes

void printLL(){
    NodeLL cur = head;
    if(cur.getNext() == null){
        System.out.println("LL is emplty");
        //System.out.println("printing Node");
        while(cur.getNext() != null){
            cur = cur.getNext();
            System.out.print(cur.getData()+ " ");


void mergeSortedList(NodeLL node1, NodeLL node2){
    NodeLL cur1 = node1.getNext();
    NodeLL cur2 = node2.getNext();

    NodeLL cur = head;
    if(cur1 == null){
        cur = node2;

    if(cur2 == null){
        cur = node1;
    while(cur1 != null && cur2 != null){

        if(cur1.getData() <= cur2.getData()){
            cur1 = cur1.getNext();
            cur2 = cur2.getNext();
        cur = cur.getNext();
    while(cur1 != null){
        cur1 = cur1.getNext();
        cur = cur.getNext();
    while(cur2 != null){
        cur2 = cur2.getNext();
        cur = cur.getNext();

How to add a JAR in NetBeans

If your project's source code has import statements that reference classes that are in widget.jar, you should add the jar to your projects Compile-time Libraries. (The jar widget.jar will automatically be added to your project's Run-time Libraries). That corresponds to (1).

If your source code has imports for classes in some other jar and the source code for those classes has import statements that reference classes in widget.jar, you should add widget.jar to the Run-time libraries list. That corresponds to (2).

You can add the jars directly to the Libraries list in the project properties. You can also create a Library that contains the jar file and then include that Library in the Compile-time or Run-time Libraries list.

If you create a NetBeans Library for widget.jar, you can also associate source code for the jar's content and Javadoc for the APIs defined in widget.jar. This additional information about widget.jar will be used by NetBeans as you debug code. It will also be used to provide addition information when you use code completion in the editor.

You should avoid using Tools >> Java Platform to add a jar to a project. That dialog allows you to modify the classpath that is used to compile and run all projects that use the Java Platform that you create. That may be useful at times but hides your project's dependency on widget.jar almost completely.

Find length (size) of an array in jquery

If length is undefined you can use:

function count(array){

    var c = 0;
    for(i in array) // in returns key, not object
        if(array[i] != undefined)

    return c;

var total = count(array);

Clone an image in cv2 python

Using python 3 and opencv-python version 4.4.0, the following code should work:

img_src = cv2.imread('image.png')
img_clone = img_src.copy()

List of Java class file format major version numbers?

If you have a class file at build/com/foo/Hello.class, you can check what java version it is compiled at using the command:

javap -v build/com/foo/Hello.class | grep "major"

Example usage:

$ javap -v build/classes/java/main/org/aguibert/liberty/Book.class | grep major
  major version: 57

According to the table in the OP, major version 57 means the class file was compiled to JDK 13 bytecode level

Very Simple, Very Smooth, JavaScript Marquee

My text marquee for more text, and position absolute enabled

(function($) {
$.fn.textWidth = function() {
var calc = document.createElement('span');
  position: 'absolute',
  visibility: 'hidden',
  height: 'auto',
  width: 'auto',
  'white-space': 'nowrap'
var width = $(calc).width();
return width;

$.fn.marquee = function(args) {
var that = $(this);
var textWidth = that.textWidth(),
    offset = that.width(),
    width = offset,
    css = {
        'text-indent': that.css('text-indent'),
        'overflow': that.css('overflow'),
        'white-space': that.css('white-space')
    marqueeCss = {
        'text-indent': width,
        'overflow': 'hidden',
        'white-space': 'nowrap'
    args = $.extend(true, {
        count: -1,
        speed: 1e1,
        leftToRight: false
    }, args),
    i = 0,
    stop = textWidth * -1,
    dfd = $.Deferred();

function go() {
    if (that.css('overflow') != "hidden") {
        that.css('text-indent', width + 'px');
        return false;
    if (!that.length) return dfd.reject();

    if (width <= stop) {
        if (i == args.count) {
            return dfd.resolve();
        if (args.leftToRight) {
            width = textWidth * -1;
        } else {
            width = offset;
    that.css('text-indent', width + 'px');
    if (args.leftToRight) {
    } else {
    setTimeout(go, args.speed);

if (args.leftToRight) {
    width = textWidth * -1;
    stop = offset;
} else {
return dfd.promise();
// $('h1').marquee();
$("h1").mouseover(function () {     
}).mouseout(function () {

Adding input elements dynamically to form

Try this JQuery code to dynamically include form, field, and delete/remove behavior:

$(document).ready(function() {_x000D_
    var max_fields = 10;_x000D_
    var wrapper = $(".container1");_x000D_
    var add_button = $(".add_form_field");_x000D_
    var x = 1;_x000D_
    $(add_button).click(function(e) {_x000D_
        if (x < max_fields) {_x000D_
            $(wrapper).append('<div><input type="text" name="mytext[]"/><a href="#" class="delete">Delete</a></div>'); //add input box_x000D_
        } else {_x000D_
            alert('You Reached the limits')_x000D_
    $(wrapper).on("click", ".delete", function(e) {_x000D_
<script src=""></script>_x000D_
<div class="container1">_x000D_
    <button class="add_form_field">Add New Field &nbsp; _x000D_
      <span style="font-size:16px; font-weight:bold;">+ </span>_x000D_
    <div><input type="text" name="mytext[]"></div>_x000D_

Refer Demo Here

Get the contents of a table row with a button click

The selector ".nr:first" is specifically looking for the first, and only the first, element having class "nr" within the selected table element. If you instead call .find(".nr") you will get all of the elements within the table having class "nr". Once you have all of those elements, you could use the .each method to iterate over them. For example:

$(".use-address").click(function() {
    $("#choose-address-table").find(".nr").each(function(i, nrElt) {
        var id = nrElt.text();
        $("#resultas").append("<p>" + id + "</p>"); // Testing: append the contents of the td to a div

However, that would get you all of the elements in the table, not just the one in the row that was clicked. To further limit your selection to the row containing the clicked button, use the .closest method, like so:

$(".use-address").click(function() {
    $(this).closest("tr").find(".nr").each(function(i, nrElt) {
        var id = nrElt.text();
        $("#resultas").append("<p>" + id + "</p>"); // Testing: append the contents of the td to a div

Useful example of a shutdown hook in Java?

Shutdown Hooks are unstarted threads that are registered with Runtime.addShutdownHook().JVM does not give any guarantee on the order in which shutdown hooks are started.For more info refer

Generate an integer that is not among four billion given ones

If you have one integer missing from the range [0, 2^x - 1] then just xor them all together. For example:

>>> 0 ^ 1 ^ 3
>>> 0 ^ 1 ^ 2 ^ 3 ^ 4 ^ 6 ^ 7

(I know this doesn't answer the question exactly, but it's a good answer to a very similar question.)

Anaconda vs. miniconda

Anaconda is a very large installation ~ 2 GB and is most useful for those users who are not familiar with installing modules or packages with other package managers.

Anaconda seems to be promoting itself as the official package manager of Jupyter. It's not. Anaconda bundles Jupyter, R, python, and many packages with its installation.

Anaconda is not necessary for installing Jupyter Lab or the R kernel. There is plenty of information available elsewhere for installing Jupyter Lab or Notebooks. There is also plenty of information elsewhere for installing R studio. The following shows how to install the R kernel directly from R Studio:

To install the R kernel, without Anaconda, start R Studio. In the R terminal window enter these three commands:


Done. Next time Jupyter is opened, the R kernel will be available.

Creating a file only if it doesn't exist in Node.js

You can do something like this:

function writeFile(i){
    var i = i || 0;
    var fileName = 'a_' + i + '.jpg';
    fs.exists(fileName, function (exists) {
        } else {

Is it possible to set a number to NaN or infinity?

Yes, you can use numpy for that.

import numpy as np
a = arange(3,dtype=float)

a[0] = np.nan
a[1] = np.inf
a[2] = -np.inf

a # is now [nan,inf,-inf]

np.isnan(a[0]) # True
np.isinf(a[1]) # True
np.isinf(a[2]) # True

How to view transaction logs in SQL Server 2008

I accidentally deleted a whole bunch of data in the wrong environment and this post was one of the first ones I found.

Because I was simultaneously panicking and searching for a solution, I went for the first thing I saw - ApexSQL Logs, which was $2000 which was an acceptable cost.

However, I've since found out that Toad for Sql Server can generate undo scripts from transaction logs and it is only $655.

Lastly, found an even cheaper option SysToolsGroup Log Analyzer and it is only $300.

Convert Enum to String

In my tests, Enum.GetName was faster and by decent margin. Internally ToString calls Enum.GetName. From source for .NET 4.0, the essentials:

public override String ToString()
     return Enum.InternalFormat((RuntimeType)GetType(), GetValue());

private static String InternalFormat(RuntimeType eT, Object value)
    if (!eT.IsDefined(typeof(System.FlagsAttribute), false))
        String retval = GetName(eT, value); //<== the one
        if (retval == null)
            return value.ToString();
            return retval;
        return InternalFlagsFormat(eT, value);

I cant say that is the reason for sure, but tests state one is faster than the other. Both the calls involve boxing (in fact they are reflection calls, you're essentially retrieving field names) and can be slow for your liking.

Test setup: enum with 8 values, no. of iterations = 1000000

Result: Enum.GetName => 700 ms, ToString => 2000 ms

If speed isn't noticeable, I wouldn't care and use ToString since it offers a much cleaner call. Contrast

Enum.GetName(typeof(Bla), value)



Use component from another module

You have to export it from your NgModule:

  declarations: [TaskCardComponent],
  exports: [TaskCardComponent],
  imports: [MdCardModule],
  providers: []
export class TaskModule{}

How to programmatically set the SSLContext of a JAX-WS client?

You can move your proxy authentication and ssl staff to soap handler

  port = new SomeService().getServicePort();
  Binding binding = ((BindingProvider) port).getBinding();
  binding.setHandlerChain(Collections.<Handler>singletonList(new ProxyHandler()));

This is my example, do all network ops

  class ProxyHandler implements SOAPHandler<SOAPMessageContext> {
    static class TrustAllHost implements HostnameVerifier {
      public boolean verify(String urlHostName, SSLSession session) {
        return true;

    static class TrustAllCert implements X509TrustManager {
      public[] getAcceptedIssuers() {
        return null;

      public void checkClientTrusted([] certs, String authType) {

      public void checkServerTrusted([] certs, String authType) {

    private SSLSocketFactory socketFactory;

    public SSLSocketFactory getSocketFactory() throws Exception {
      // just an example
      if (socketFactory == null) {
        SSLContext sc = SSLContext.getInstance("SSL");
        TrustManager[] trustAllCerts = new TrustManager[] { new TrustAllCert() };
        sc.init(null, trustAllCerts, new;
        socketFactory = sc.getSocketFactory();

      return socketFactory;

    @Override public boolean handleMessage(SOAPMessageContext msgCtx) {
      if (!Boolean.TRUE.equals(msgCtx.get(MessageContext.MESSAGE_OUTBOUND_PROPERTY)))
        return true;

      HttpURLConnection http = null;

      try {
        SOAPMessage outMessage = msgCtx.getMessage();
        outMessage.setProperty(SOAPMessage.CHARACTER_SET_ENCODING, "UTF-8");
        // outMessage.setProperty(SOAPMessage.WRITE_XML_DECLARATION, true); // Not working. WTF?

        ByteArrayOutputStream message = new ByteArrayOutputStream(2048);
        message.write("<?xml version='1.0' encoding='UTF-8'?>".getBytes("UTF-8"));

        String endpoint = (String) msgCtx.get(BindingProvider.ENDPOINT_ADDRESS_PROPERTY);
        URL service = new URL(endpoint);

        Proxy proxy = Proxy.NO_PROXY;
        //Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress("{proxy.url}", {proxy.port}));

        http = (HttpURLConnection) service.openConnection(proxy);
        http.setReadTimeout(60000); // set your timeout

        if (http instanceof HttpsURLConnection) {
          HttpsURLConnection https = (HttpsURLConnection) http;
          https.setHostnameVerifier(new TrustAllHost());

        http.setRequestProperty("Content-Type", "application/soap+xml; charset=utf-8");
        http.setRequestProperty("Content-Length", Integer.toString(message.size()));
        http.setRequestProperty("SOAPAction", "");
        http.setRequestProperty("Host", service.getHost());
        //http.setRequestProperty("Proxy-Authorization", "Basic {proxy_auth}");

        InputStream in = null;
        OutputStream out = null;

        try {
          out = http.getOutputStream();
        } finally {
          if (out != null) {

        int responseCode = http.getResponseCode();
        MimeHeaders responseHeaders = new MimeHeaders();

        try {
          in = http.getInputStream();
          IOUtils.copy(in, message);
        } catch (final IOException e) {
          try {
            in = http.getErrorStream();
            IOUtils.copy(in, message);
          } catch (IOException e1) {
            throw new RuntimeException("Unable to read error body", e);
        } finally {
          if (in != null)

        for (Map.Entry<String, List<String>> header : http.getHeaderFields().entrySet()) {
          String name = header.getKey();

          if (name != null)
            for (String value : header.getValue())
              responseHeaders.addHeader(name, value);

        SOAPMessage inMessage = MessageFactory.newInstance()
          .createMessage(responseHeaders, new ByteArrayInputStream(message.toByteArray()));

        if (inMessage == null)
          throw new RuntimeException("Unable to read server response code " + responseCode);

        return false;
      } catch (Exception e) {
        throw new RuntimeException("Proxy error", e);
      } finally {
        if (http != null)

    @Override public boolean handleFault(SOAPMessageContext context) {
      return false;

    @Override public void close(MessageContext context) {

    @Override public Set<QName> getHeaders() {
      return Collections.emptySet();

It use UrlConnection, you can use any library you want in handler. Have fun!

How to format a URL to get a file from Amazon S3?

Perhaps not what the OP was after, but for those searching the URL to simply access a readable object on S3 is more like:


Where <region> is something like s3-ap-southeast-2.

Click on the item in the S3 GUI to get the link for your bucket.

How to find pg_config path

sudo find / -name "pg_config" -print

The answer is /Library/PostgreSQL/9.1/bin/pg_config in my configuration (MAC Maverick)

How to count the number of occurrences of an element in a List

A slightly more efficient approach might be

Map<String, AtomicInteger> instances = new HashMap<String, AtomicInteger>();

void add(String name) {
     AtomicInteger value = instances.get(name);
     if (value == null) 
        instances.put(name, new AtomicInteger(1));

Setting a max character length in CSS


<div id="dash">
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin nisi ligula, dapibus a volutpat sit amet, mattis et dui. Nunc porttitor accumsan orci id luctus. Phasellus ipsum metus, tincidunt non rhoncus id, dictum a lectus. Nam sed ipsum a urna ac


var p = $('#dash p');
var ks = $('#dash').height();
while ($(p).outerHeight() > ks) {
  $(p).text(function(index, text) {
    return text.replace(/\W*\s(\S)*$/, '...');


#dash {
  width: 400px;
  height: 60px;
  overflow: hidden;

#dash p {
  padding: 10px;
  margin: 0;


Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin nisi ligula, dapibus a volutpat sit amet, mattis et...


How to get request URL in Spring Boot RestController

Allows getting any URL on your system, not just a current one.

import org.springframework.hateoas.mvc.ControllerLinkBuilder
ControllerLinkBuilder linkBuilder = ControllerLinkBuilder.linkTo(methodOn(YourController.class).getSomeEntityMethod(parameterId, parameterTwoId))

URI methodUri = linkBuilder.Uri()
String methodUrl = methodUri.getPath()