Programs & Examples On #Docutils

a general purpose document processing system written in Python.

reStructuredText tool support

Salvaging (and extending) the list from an old version of the Wikipedia page:



Although the reference implementation of reStructuredText is written in Python, there are reStructuredText parsers in other languages too.

Python - Docutils

The main distribution of reStructuredText is the Python Docutils package. It contains several conversion tools:

  • rst2html - from reStructuredText to HTML
  • rst2xml - from reStructuredText to XML
  • rst2latex - from reStructuredText to LaTeX
  • rst2odt - from reStructuredText to ODF Text (word processor) document.
  • rst2s5 - from reStructuredText to S5, a Simple Standards-based Slide Show System
  • rst2man - from reStructuredText to Man page

Haskell - Pandoc

Pandoc is a Haskell library for converting from one markup format to another, and a command-line tool that uses this library. It can read Markdown and (subsets of) reStructuredText, HTML, and LaTeX, and it can write Markdown, reStructuredText, HTML, LaTeX, ConTeXt, PDF, RTF, DocBook XML, OpenDocument XML, ODT, GNU Texinfo, MediaWiki markup, groff man pages, and S5 HTML slide shows.

There is an Pandoc online tool (POT) to try this library. Unfortunately, compared to the reStructuredText online renderer (ROR),

  • POT truncates input rather more shortly. The POT user must render input in chunks that could be rendered whole by the ROR.
  • POT output lacks the helpful error messages displayed by the ROR (and generated by docutils)

Java - JRst

JRst is a Java reStructuredText parser. It can currently output HTML, XHTML, DocBook xdoc and PDF, BUT seems to have serious problems: neither PDF or (X)HTML generation works using the current full download, result pages in (X)HTML are empty and PDF generation fails on IO problems with XSL files (not bundled??). Note that the original JRst has been removed from the website; a fork is found on GitHub.

Scala - Laika

Laika is a new library for transforming markup languages to other output formats. Currently it supports input from Markdown and reStructuredText and produce HTML output. The library is written in Scala but should be also usable from Java.





The Nim compiler features the commands rst2htmland rst2tex which transform reStructuredText files to HTML and TeX files. The standard library provides the following modules (used by the compiler) to handle reStructuredText files programmatically:

  • rst - implements a reStructuredText parser
  • rstast - implements an AST for the reStructuredText parser
  • rstgen - implements a generator of HTML/Latex from reStructuredText

Other 3rd party converters

Most (but not all) of these tools are based on Docutils (see above) and provide conversion to or from formats that might not be supported by the main distribution.

From reStructuredText

  • restview - This pip-installable python package requires docutils, which does the actual rendering. restview's major ease-of-use feature is that, when you save changes to your document(s), it automagically re-renders and re-displays them. restview
    1. starts a small web server
    2. calls docutils to render your document(s) to HTML
    3. calls your device's browser to display the output HTML.
  • rst2pdf - from reStructuredText to PDF
  • rst2odp - from reStructuredText to ODF Presentation
  • rst2beamer - from reStructuredText to LaTeX beamer Presentation class
  • Wikir - from reStructuredText to a Google (and possibly other) Wiki formats
  • rst2qhc - Convert a collection of reStructuredText files into a Qt (toolkit) Help file and (optional) a Qt Help Project file

To reStructuredText

  • xml2rst is an XSLT script to convert Docutils internal XML representation (back) to reStructuredText
  • Pandoc (see above) can also convert from Markdown, HTML and LaTeX to reStructuredText
  • db2rst is a simple and limited DocBook to reStructuredText translator
  • pod2rst - convert .pod files to reStructuredText files


Some projects use reStructuredText as a baseline to build on, or provide extra functionality extending the utility of the reStructuredText tools.


The Sphinx documentation generator translates a set of reStructuredText source files into various output formats, automatically producing cross-references, indices etc.


rest2web is a simple tool that lets you build your website from a single template (or as many as you want), and keep the contents in reStructuredText.


Pygments is a generic syntax highlighter for general use in all kinds of software such as forum systems, Wikis or other applications that need to prettify source code. See Using Pygments in reStructuredText documents.

Free Editors

While any plain text editor is suitable to write reStructuredText documents, some editors have better support than others.


The Emacs support via rst-mode comes as part of the Docutils package under /docutils/tools/editors/emacs/rst.el


The vim-common package for that comes with most GNU/Linux distributions has reStructuredText syntax highlight and indentation support of reStructuredText out of the box:


There is a rst mode for the Jed programmers editor.


gedit, the official text editor of the GNOME desktop environment. There is a gedit reStructuredText plugin.


Geany, a small and lightweight Integrated Development Environment include support for reStructuredText from version 0.12 (October 10, 2007).


Leo, an outlining editor for programmers, supports reStructuredText via rst-plugin or via "@auto-rst" nodes (it's not well-documented, but @auto-rst nodes allow editing rst files directly, parsing the structure into the Leo outline).

It also provides a way to preview the resulting HTML, in a "viewrendered" pane.


The FTE Folding Text Editor - a free (licensed under the GNU GPL) text editor for developers. FTE has a mode for reStructuredText support. It provides color highlighting of basic RSTX elements and special menu that provide easy way to insert most popular RSTX elements to a document.


PyK is a successor of PyEdit and reStInPeace, written in Python with the help of the Qt4 toolkit.


The Eclipse IDE with the ReST Editor plug-in provides support for editing reStructuredText files.


NoTex is a browser based (general purpose) text editor, with integrated project management and syntax highlighting. Plus it enables to write books, reports, articles etc. using rST and convert them to LaTex, PDF or HTML. The PDF files are of high publication quality and are produced via Sphinx with the Texlive LaTex suite.


Notepad++ is a general purpose text editor for Windows. It has syntax highlighting for many languages built-in and support for reStructuredText via a user defined language for reStructuredText.

Visual Studio Code

Visual Studio Code is a general purpose text editor for Windows/macOS/Linux. It has syntax highlighting for many languages built-in and supports reStructuredText via an extension from LeXtudio.

Dedicated reStructuredText Editors

Proprietary editors

Sublime Text

Sublime Text is a completely customizable and extensible source code editor available for Windows, OS X, and Linux. Registration is required for long-term use, but all functions are available in the unregistered version, with occasional reminders to purchase a license. Versions 2 and 3 (currently in beta) support reStructuredText syntax highlighting by default, and several plugins are available through the package manager Package Control to provide snippets and code completion, additional syntax highlighting, conversion to/from RST and other formats, and HTML preview in the browser.

BBEdit / TextWrangler

BBEdit (and its free variant TextWrangler) for Mac can syntax-highlight reStructuredText using this codeless language module.


TextMate, a proprietary general-purpose GUI text editor for Mac OS X, has a bundle for reStructuredText.


Intype is a proprietary text editor for Windows, that support reStructuredText out of the box.

E Text Editor

E is a proprietary Text Editor licensed under the "Open Company License". It supports TextMate's bundles, so it should support reStructuredText the same way TextMate does.


PyCharm (and other IntelliJ platform IDEs?) has ReST/Sphinx support (syntax highlighting, autocomplete and preview).instant preview)


here are some Wiki programs that support the reStructuredText markup as the native markup syntax, or as an add-on:


MediaWiki reStructuredText extension allows for reStructuredText markup in MediaWiki surrounded by <rst> and </rst>.


MoinMoin is an advanced, easy to use and extensible WikiEngine with a large community of users. Said in a few words, it is about collaboration on easily editable web pages.

There is a reStructuredText Parser for MoinMoin.


Trac is an enhanced wiki and issue tracking system for software development projects. There is a reStructuredText Support in Trac.

This Wiki

This Wiki is a Webware for Python Wiki written by Ian Bicking. This wiki uses ReStructuredText for its markup.


rstiki is a minimalist single-file personal wiki using reStructuredText syntax (via docutils) inspired by pwyky. It does not support authorship indication, versioning, hierarchy, chrome/framing/templating or styling. It leverages docutils/reStructuredText as the wiki syntax. As such, it's under 200 lines of code, and in a single file. You put it in a directory and it runs.


Ikiwiki is a wiki compiler. It converts wiki pages into HTML pages suitable for publishing on a website. Ikiwiki stores pages and history in a revision control system such as Subversion or Git. There are many other features, including support for blogging, as well as a large array of plugins. It's reStructuredText plugin, however is somewhat limited and is not recommended as its' main markup language at this time.

Web Services


An Online reStructuredText editor can be used to play with the markup and see the results immediately.

Blogging frameworks


WordPreSt reStructuredText plugin for WordPress. (PHP)


reStructuredText parser plugin for Zine (will become obsolete in version 0.2 when Zine is scheduled to get a native reStructuredText support). Zine is discontinued. (Python)


Pelican is a static blog generator that supports writing articles in ReST. (Python)


Hyde is a static website generator that supports ReST. (Python)


Acrylamid is a static blog generator that supports writing articles in ReST. (Python)


Nikola is a Static Site and Blog Generator that supports ReST. (Python)

ipsum genera

Ipsum genera is a static blog generator written in Nim.


Yozuch is a static blog generator written in Python.


What is the difference between LATERAL and a subquery in PostgreSQL?

What is a LATERAL join?

The feature was introduced with PostgreSQL 9.3.
Quoting the manual:

Subqueries appearing in FROM can be preceded by the key word LATERAL. This allows them to reference columns provided by preceding FROM items. (Without LATERAL, each subquery is evaluated independently and so cannot cross-reference any other FROM item.)

Table functions appearing in FROM can also be preceded by the key word LATERAL, but for functions the key word is optional; the function's arguments can contain references to columns provided by preceding FROM items in any case.

Basic code examples are given there.

More like a correlated subquery

A LATERAL join is more like a correlated subquery, not a plain subquery, in that expressions to the right of a LATERAL join are evaluated once for each row left of it - just like a correlated subquery - while a plain subquery (table expression) is evaluated once only. (The query planner has ways to optimize performance for either, though.)
Related answer with code examples for both side by side, solving the same problem:

For returning more than one column, a LATERAL join is typically simpler, cleaner and faster.
Also, remember that the equivalent of a correlated subquery is LEFT JOIN LATERAL ... ON true:

Things a subquery can't do

There are things that a LATERAL join can do, but a (correlated) subquery cannot (easily). A correlated subquery can only return a single value, not multiple columns and not multiple rows - with the exception of bare function calls (which multiply result rows if they return multiple rows). But even certain set-returning functions are only allowed in the FROM clause. Like unnest() with multiple parameters in Postgres 9.4 or later. The manual:

This is only allowed in the FROM clause;

So this works, but cannot (easily) be replaced with a subquery:

CREATE TABLE tbl (a1 int[], a2 int[]);
SELECT * FROM tbl, unnest(a1, a2) u(elem1, elem2);  -- implicit LATERAL

The comma (,) in the FROM clause is short notation for CROSS JOIN.
LATERAL is assumed automatically for table functions.
About the special case of UNNEST( array_expression [, ... ] ):

Set-returning functions in the SELECT list

You can also use set-returning functions like unnest() in the SELECT list directly. This used to exhibit surprising behavior with more than one such function in the same SELECT list up to Postgres 9.6. But it has finally been sanitized with Postgres 10 and is a valid alternative now (even if not standard SQL). See:

Building on above example:

SELECT *, unnest(a1) AS elem1, unnest(a2) AS elem2
FROM   tbl;


dbfiddle for pg 9.6 here
dbfiddle for pg 10 here

Clarify misinformation

The manual:

For the INNER and OUTER join types, a join condition must be specified, namely exactly one of NATURAL, ON join_condition, or USING (join_column [, ...]). See below for the meaning.
For CROSS JOIN, none of these clauses can appear.

So these two queries are valid (even if not particularly useful):

FROM   tbl t

FROM   tbl t, LATERAL (SELECT * FROM b WHERE b.t_id = t.t_id) t;

While this one is not:

FROM   tbl t
LEFT   JOIN LATERAL (SELECT * FROM b WHERE b.t_id = t.t_id) t;

That's why Andomar's code example is correct (the CROSS JOIN does not require a join condition) and Attila's is was not.

What are OLTP and OLAP. What is the difference between them?

The difference is quite simple:

OLTP (Online Transaction Processing)

OLTP is a class of information systems that facilitate and manage transaction-oriented applications. OLTP has also been used to refer to processing in which the system responds immediately to user requests. Online transaction processing applications are high throughput and insert or update-intensive in database management. Some examples of OLTP systems include order entry, retail sales, and financial transaction systems.

OLAP (Online Analytical Processing)

OLAP is part of the broader category of business intelligence, which also encompasses relational database, report writing and data mining. Typical applications of OLAP include business reporting for sales, marketing, management reporting, business process management (BPM), budgeting and forecasting, financial reporting and similar areas.

See more details OLTP and OLAP

Pure Javascript listen to input value change

Default usage

el.addEventListener('input', function () {

But, if you want to fire event when you change inputs value manualy via JS you should use custom event(any name, like 'myEvent' \ 'ev' etc.) IF you need to listen forms 'change' or 'input' event and you change inputs value via JS - you can name your custom event 'change' \ 'input' and it will work too.

var event = new Event('input');
el.addEventListener('input', function () { 
form.addEventListener('input', function () { 

el.value = 'something';

In Java, how to find if first character in a string is upper case without regex

Don't forget to check whether the string is empty or null. If we forget checking null or empty then we would get NullPointerException or StringIndexOutOfBoundException if a given String is null or empty.

public class StartWithUpperCase{

        public static void main(String[] args){

            String str1 = ""; //StringIndexOfBoundException if 
                              //empty checking not handled
            String str2 = null; //NullPointerException if 
                                //null checking is not handled.
            String str3 = "Starts with upper case";
            String str4 = "starts with lower case";

            System.out.println(startWithUpperCase(str1)); //false
            System.out.println(startWithUpperCase(str2)); //false
            System.out.println(startWithUpperCase(str3)); //true
            System.out.println(startWithUpperCase(str4)); //false


        public static boolean startWithUpperCase(String givenString){

            if(null == givenString || givenString.isEmpty() ) return false;
            else return (Character.isUpperCase( givenString.codePointAt(0) ) );


Are multi-line strings allowed in JSON?

JSON doesn't allow breaking lines for readability.

Your best bet is to use an IDE that will line-wrap for you.

Extract digits from a string in Java

public String extractDigits(String src) {
    StringBuilder builder = new StringBuilder();
    for (int i = 0; i < src.length(); i++) {
        char c = src.charAt(i);
        if (Character.isDigit(c)) {
    return builder.toString();

AngularJS: Service vs provider vs factory

1.Services are singleton objects that are created when necessary and are never cleaned up until the end of the application life-cycle (when the browser is closed). Controllers are destroyed and cleaned up when they are no longer needed.

2.The easiest way to create a service is by using the factory() method. The factory() method allows us to define a service by returning an object that contains service functions and service data. The service definition function is where we place our injectable services, such as $http and $q. Ex:

.factory('User', function($http) { // injectables go here
var backendUrl = "http://localhost:3000"; var service = {
    // our factory definition
user: {},
setName: function(newName) {
      service.user['name'] = newName;
setEmail: function(newEmail) { service.user['email'] = newEmail;
save: function() {
return $ + '/users', { user: service.user
}); }
return service; });

Using the factory() in our app

It’s easy to use the factory in our application as we can simply inject it where we need it at run-time.

.controller('MainController', function($scope, User) {
  $scope.saveUser =;
  1. The service() method, on the other hand allows us to create a service by defining a constructor function. We can use a prototypical object to define our service, instead of a raw javascript object. Similar to the factory() method, we’ll also set the injectables in the function definition.
  2. The lowest level way to create a service is by using the provide() method. This is the only way to create a service that we can configure using the .config() function. Unlike the previous to methods, we’ll set the injectables in a defined this.$get() function definition.

Static nested class in Java, why?

Non static inner classes can result in memory leaks while static inner class will protect against them. If the outer class holds considerable data, it can lower the performance of the application.

SVG gradient using CSS

Here is how to set a linearGradient on a target element:

<style type="text/css">
    <linearGradient id="MyGradient">
        <stop offset="0%" stop-color="#e4e4e3" ></stop>
        <stop offset="80%" stop-color="#fff" ></stop>

How to view kafka message

Use the Kafka consumer provided by Kafka :

bin/ --bootstrap-server BROKERS --topic TOPIC_NAME

It will display the messages as it will receive it. Add --from-beginning if you want to start from the beginning.

Excel Calculate the date difference from today from a cell of "7/6/2012 10:26:42"

You can use the datedif function to find out difference in days.


Quote from

The mysterious datedif function in Microsoft Excel

The Datedif function is used to calculate interval between two dates in days, months or years.

This function is available in all versions of Excel but is not documented. It is not even listed in the "Insert Function" dialog box. Hence it must be typed manually in the formula box. Syntax

DATEDIF( start_date, end_date, interval_unit )

start_date from date end_date to date (must be after start_date) interval_unit Unit to be used for output interval Values for interval_unit

interval_unit Description

D Number of days

M Number of complete months

Y Number of complete years

YD Number of days excluding years

MD Number of days excluding months and years

YM Number of months excluding years


Error Description

#NUM! The end_date is later than (greater than) the start_date or interval_unit has an invalid value. #VALUE! end_date or start_date is invalid.

How can I find all of the distinct file extensions in a folder hierarchy?

Find everythin with a dot and show only the suffix.

find . -type f -name "*.*" | awk -F. '{print $NF}' | sort -u

if you know all suffix have 3 characters then

find . -type f -name "*.???" | awk -F. '{print $NF}' | sort -u

or with sed shows all suffixes with one to four characters. Change {1,4} to the range of characters you are expecting in the suffix.

find . -type f | sed -n 's/.*\.\(.\{1,4\}\)$/\1/p'| sort -u

What does servletcontext.getRealPath("/") mean and when should I use it

A web application's context path is the directory that contains the web application's WEB-INF directory. It can be thought of as the 'home' of the web app. Often, when writing web applications, it can be important to get the actual location of this directory in the file system, since this allows you to do things such as read from files or write to files.

This location can be obtained via the ServletContext object's getRealPath() method. This method can be passed a String parameter set to File.separator to get the path using the operating system's file separator ("/" for UNIX, "\" for Windows).

How to use addTarget method in swift 3

Try this

button.addTarget(self, action:#selector(handleRegister()), for: .touchUpInside). 

Just add parenthesis with name of method.

Also you can refer link : Value of type 'CustomButton' has no member 'touchDown'

Java - Change int to ascii

In fact in the last answer String strAsciiTab = Character.toString((char) iAsciiValue); the essential part is (char)iAsciiValue which is doing the job (Character.toString useless)

Meaning the first answer was correct actually char ch = (char) yourInt;

if in yourint=49 (or 0x31), ch will be '1'

How to validate an e-mail address in swift?

Create simple extension:

extension NSRegularExpression {

    convenience init(pattern: String) {
        try! self.init(pattern: pattern, options: [])

extension String {

    var isValidEmail: Bool {
        return isMatching(expression: NSRegularExpression(pattern: "^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$"))

    //MARK: - Private

    private func isMatching(expression: NSRegularExpression) -> Bool {
        return expression.numberOfMatches(in: self, range: NSRange(location: 0, length: characters.count)) > 0


"[email protected]".isValidEmail //true
"b@bb".isValidEmail //false

You can extend following extension to anything you need: isValidPhoneNumber, isValidPassword etc...

How do I change the default port (9000) that Play uses when I execute the "run" command?

for play 2.5.x

Step 1: Stop the netty server (if it is running) using control + D

Step 2: go to sbt-dist/conf

Step 3: edit this file 'sbtConfig.txt' with this


Step 4: Start the server

Step 5: http://host:9005/

The iOS Simulator deployment targets is set to 7.0, but the range of supported deployment target version for this platform is 8.0 to 12.1

If your are come from react-native and facing this error just do this

  1. Open Podfile(your project > ios>Podfile)
  2. comment flipper functions in podfile as below
 #post_install do |installer|
  1. In terminal inside IOS folder enter this command pod install

yep, that is it hope it works to you

List of foreign keys and the tables they reference in Oracle DB

SELECT a.table_name, a.column_name, a.constraint_name, c.owner, 
       -- referenced pk
       c.r_owner, c_pk.table_name r_table_name, c_pk.constraint_name r_pk
  FROM all_cons_columns a
  JOIN all_constraints c ON a.owner = c.owner
                        AND a.constraint_name = c.constraint_name
  JOIN all_constraints c_pk ON c.r_owner = c_pk.owner
                           AND c.r_constraint_name = c_pk.constraint_name
 WHERE c.constraint_type = 'R'
   AND a.table_name :=TABLE_NAME
   AND c.owner :=OWNER_NAME;

Oracle SQL Developer: Failure - Test failed: The Network Adapter could not establish the connection?

I am answering this for the benefit of future community users. There were multiple issues. If you encounter this problem, I suggest you look for the following:

  • Make sure your tnsnames.ora is complete and has the databases you wish to connect to
  • Make sure you can tnsping the server you wish to connect to
  • On the server, make sure it will be open on the port you desire with the specific application you are using.

Once I did these three things, I solved my problem.

How to list active connections on PostgreSQL?

SELECT * FROM pg_stat_activity WHERE datname = 'dbname' and state = 'active';

Since pg_stat_activity contains connection statistics of all databases having any state, either idle or active, database name and connection state should be included in the query to get the desired output.

How to handle ETIMEDOUT error?

This is caused when your request response is not received in given time(by timeout request module option).

Basically to catch that error first, you need to register a handler on error, so the unhandled error won't be thrown anymore: out.on('error', function (err) { /* handle errors here */ }). Some more explanation here.

In the handler you can check if the error is ETIMEDOUT and apply your own logic: if (err.message.code === 'ETIMEDOUT') { /* apply logic */ }.

If you want to request for the file again, I suggest using node-retry or node-backoff modules. It makes things much simpler.

If you want to wait longer, you can set timeout option of request yourself. You can set it to 0 for no timeout.

How to Set OnClick attribute with value containing function in ie8?

You don't need to use setAttribute for that - This code works (IE8 also)

<div id="something" >Hello</div>
<script type="text/javascript" >
    (function() {
        document.getElementById("something").onclick = function() { 

How to programmatically close a JFrame

Not only to close the JFrame but also to trigger WindowListener events, try this:

myFrame.dispatchEvent(new WindowEvent(myFrame, WindowEvent.WINDOW_CLOSING));

Convert object string to JSON

Maybe you have to try this:

str = jQuery.parseJSON(str)


To avoid x !instance of Long prob Add

<property name="openjpa.Compatibility" value="StrictIdentityValues=false"/>

in your persistence.xml

Java: Getting a substring from a string starting after a particular character

You can use Apache commons:

For substring after last occurrence use this method.

And for substring after first occurrence equivalent method is here.

Select info from table where row has max date

SELECT group,MAX(date) as max_date
FROM table
WHERE checks>0
GROUP BY group

That works to get the max date..join it back to your data to get the other columns:

Select group,max_date,checks
from table t
inner join 
(SELECT group,MAX(date) as max_date
FROM table
WHERE checks>0
GROUP BY group)a
on = and a.max_date = date

Inner join functions as the filter to get the max record only.

FYI, your column names are horrid, don't use reserved words for columns (group, date, table).

Convert XML String to Object

You have two possibilities.

Method 1. XSD tool

Suppose that you have your XML file in this location C:\path\to\xml\file.xml

  1. Open Developer Command Prompt
    You can find it in Start Menu > Programs > Microsoft Visual Studio 2012 > Visual Studio Tools Or if you have Windows 8 can just start typing Developer Command Prompt in Start screen
  2. Change location to your XML file directory by typing cd /D "C:\path\to\xml"
  3. Create XSD file from your xml file by typing xsd file.xml
  4. Create C# classes by typing xsd /c file.xsd

And that's it! You have generated C# classes from xml file in C:\path\to\xml\file.cs

Method 2 - Paste special

Required Visual Studio 2012+ with .Net Framework >= 4.5 as project target and 'Windows Communication Foundation' individual component installed

  1. Copy content of your XML file to clipboard
  2. Add to your solution new, empty class file (Shift+Alt+C)
  3. Open that file and in menu click Edit > Paste special > Paste XML As Classes
    enter image description here

And that's it!


Usage is very simple with this helper class:

using System;
using System.IO;
using System.Web.Script.Serialization; // Add reference: System.Web.Extensions
using System.Xml;
using System.Xml.Serialization;

namespace Helpers
    internal static class ParseHelpers
        private static JavaScriptSerializer json;
        private static JavaScriptSerializer JSON { get { return json ?? (json = new JavaScriptSerializer()); } }

        public static Stream ToStream(this string @this)
            var stream = new MemoryStream();
            var writer = new StreamWriter(stream);
            stream.Position = 0;
            return stream;

        public static T ParseXML<T>(this string @this) where T : class
            var reader = XmlReader.Create(@this.Trim().ToStream(), new XmlReaderSettings() { ConformanceLevel = ConformanceLevel.Document });
            return new XmlSerializer(typeof(T)).Deserialize(reader) as T;

        public static T ParseJSON<T>(this string @this) where T : class
            return JSON.Deserialize<T>(@this.Trim());

All you have to do now, is:

    public class JSONRoot
        public catalog catalog { get; set; }
    // ...

    string xml = File.ReadAllText(@"D:\file.xml");
    var catalog1 = xml.ParseXML<catalog>();

    string json = File.ReadAllText(@"D:\file.json");
    var catalog2 = json.ParseJSON<JSONRoot>();

Multi value Dictionary

If you are trying to group values together this may be a great opportunity to create a simple struct or class and use that as the value in a dictionary.

public struct MyValue
    public object Value1;
    public double Value2;

then you could have your dictionary

var dict = new Dictionary<int, MyValue>();

you could even go a step further and implement your own dictionary class that will handle any special operations that you would need. for example if you wanted to have an Add method that accepted an int, object, and double

public class MyDictionary : Dictionary<int, MyValue>
    public void Add(int key, object value1, double value2)
        MyValue val;
        val.Value1 = value1;
        val.Value2 = value2;
        this.Add(key, val);

then you could simply instantiate and add to the dictionary like so and you wouldn't have to worry about creating 'MyValue' structs:

var dict = new MyDictionary();
dict.Add(1, new Object(), 2.22);

How can I provide multiple conditions for data trigger in WPF?

@jasonk - if you want to have "or" then negate all conditions since (A and B) <=> ~(~A or ~B)

but if you have values other than boolean try using type converters:

    <Condition Value="True">
            <MultiBinding Converter="{StaticResource conditionConverter}">
                <Binding Path="Name" />
                <Binding Path="State" />
        <Setter Property="Background" Value="Cyan" />

you can use the values in Convert method any way you like to produce a condition which suits you.

'this' implicitly has type 'any' because it does not have a type annotation

For method decorator declaration with configuration "noImplicitAny": true, you can specify type of this variable explicitly depends on @tony19's answer

function logParameter(this:any, target: Object, propertyName: string) {

jQuery scrollTop() doesn't seem to work in Safari or Chrome (Windows)

I was facing this problem, I created this link at the bottom and implemented the jQuery scrollTop code and it worked perfectly in Firefox, IE, Opera but didn't work in Chrome and Safari. I'm learning jQuery so I don't know if this solution is technically perfect but this worked for me. I just implemented 2 ScrollTop codes the first one uses $('html') which works for Firefox, etc. The second one uses $('html body') this works for Chrome and Safari.

$('a#top').click(function() {

    $('html').animate({scrollTop: 0}, 'slow');
    return false;

    $('html body').animate({scrollTop: 0}, 'slow');
    return false;

Uploading multiple files using formData()

Adding [] when appending to fd works, but if you prefer to have your data grouped by file then I'd suggest doing it this way:

var files= document.getElementById('inpFile').files
var fd = new FormData()

for (let i = 0; i < files.length; i++) {
  fd.append(i, files[i])

Now your data will be sent grouped by file instead of grouped by attribute.

How to check heap usage of a running JVM from the command line?

If you start execution with gc logging turned on you get the info on file. Otherwise 'jmap -heap ' will give you what you want. See the jmap doc page for more.

Please note that jmap should not be used in a production environment unless absolutely needed as the tool halts the application to be able to determine actual heap usage. Usually this is not desired in a production environment.

How to read one single line of csv data in Python?

From the Python documentation:

And while the module doesn’t directly support parsing strings, it can easily be done:

import csv
for row in csv.reader(['one,two,three']):
    print row

Just drop your string data into a singleton list.

Header div stays at top, vertical scrolling div below with scrollbar only attached to that div

You need to use js get better height for body div

<div id="head" style="height:50px; width=100%; font-size:50px;">This is head</div>
<div id="body" style="height:700px; font-size:100px; white-space:pre-wrap;    overflow:scroll;">
This is body



Error: macro names must be identifiers using #ifdef 0

Use the following to evaluate an expression (constant 0 evaluates to false).

#if 0

CSS3 Continuous Rotate Animation (Just like a loading sundial)

You also might notice a little lag because 0deg and 360deg are the same spot, so it is going from spot 1 in a circle back to spot 1. It is really insignificant, but to fix it, all you have to do is change 360deg to 359deg

my jsfiddle illustrates your animation:

#myImg {
    -webkit-animation: rotation 2s infinite linear;

@-webkit-keyframes rotation {
    from {-webkit-transform: rotate(0deg);}
    to   {-webkit-transform: rotate(359deg);}

Also what might be more resemblant of the apple loading icon would be an animation that transitions the opacity/color of the stripes of gray instead of rotating the icon.

How do I write a compareTo method which compares objects?

Listen to @milkplusvellocet, I'd recommend you to implement the Comparable interface to your class as well.

Just contributing to the answers of others:

String.compareTo() will tell you how different a string is from another.

e.g. System.out.println( "Test".compareTo("Tesu") ); will print -1 and System.out.println( "Test".compareTo("Tesa") ); will print 19

and nerdy and geeky one-line solution to this task would be:

return this.lastName.equals(s.getLastName()) ? this.lastName.compareTo(s.getLastName()) : this.firstName.compareTo(s.getFirstName());


this.lastName.equals(s.getLastName()) checks whether lastnames are the same or not this.lastName.compareTo(s.getLastName()) if yes, then returns comparison of last name. this.firstName.compareTo(s.getFirstName()) if not, returns the comparison of first name.

Removing items from a ListBox in

Already tested by me, it works fine

For i =0 To ListBox2.items.count - 1

Android ListView in fragment example

Your Fragment can subclass ListFragment.
And onCreateView() from ListFragment will return a ListView you can then populate.

What techniques can be used to speed up C++ compilation times?

Here are some:

  • Use all processor cores by starting a multiple-compile job (make -j2 is a good example).
  • Turn off or lower optimizations (for example, GCC is much faster with -O1 than -O2 or -O3).
  • Use precompiled headers.

A Space between Inline-Block List Items

just remove the breaks between li's in your html code... make the li's in one line only..

Get environment value in controller

As @Rajib pointed out, You can't access your env variables using config('myVariable')

  1. You have to add the variable to .env file first.
  2. Add the variable to some config file in config directory. I usually add to config/app.php
  3. Once done, will access them like Config::get('fileWhichContainsVariable.Variable'); using the Config Facade

Probably You will have to clear config cache using php artisan config:clear AND you will also have to restart server.

What is thread safe or non-thread safe in PHP?

Apache MPM prefork with modphp is used because it is easy to configure/install. Performance-wise it is fairly inefficient. My preferred way to do the stack, FastCGI/PHP-FPM. That way you can use the much faster MPM Worker. The whole PHP remains non-threaded, but Apache serves threaded (like it should).

So basically, from bottom to top


Apache + MPM Worker + ModFastCGI (NOT FCGI) |(or)| Cherokee |(or)| Nginx


ModFCGI does not correctly support PHP-FPM, or any external FastCGI applications. It only supports non-process managed FastCGI scripts. PHP-FPM is the PHP FastCGI process manager.

How to do a num_rows() on COUNT query in codeigniter?

I'd suggest instead of doing another query with the same parameters just immediately running a SELECT FOUND_ROWS()

How to generate List<String> from SQL query?

Loop through the Items and Add to the Collection. You can use the Add method

List<string>items=new List<string>();
using (var con= new SqlConnection("yourConnectionStringHere")
    string qry="SELECT Column1 FROM Table1";
    var cmd= new SqlCommand(qry, con);
    cmd.CommandType = CommandType.Text;
    using (SqlDataReader objReader = cmd.ExecuteReader())
        if (objReader.HasRows)
            while (objReader.Read())
              //I would also check for DB.Null here before reading the value.
               string item= objReader.GetString(objReader.GetOrdinal("Column1"));

How to test if a string contains one of the substrings in a list, in pandas?

Here is a one line lambda that also works:

df["TrueFalse"] = df['col1'].apply(lambda x: 1 if any(i in x for i in searchfor) else 0)


searchfor = ['og', 'at']

df = pd.DataFrame([('cat', 1000.0), ('hat', 2000000.0), ('dog', 1000.0), ('fog', 330000.0),('pet', 330000.0)], columns=['col1', 'col2'])

   col1  col2
0   cat 1000.0
1   hat 2000000.0
2   dog 1000.0
3   fog 330000.0
4   pet 330000.0

Apply Lambda:

df["TrueFalse"] = df['col1'].apply(lambda x: 1 if any(i in x for i in searchfor) else 0)


    col1    col2        TrueFalse
0   cat     1000.0      1
1   hat     2000000.0   1
2   dog     1000.0      1
3   fog     330000.0    1
4   pet     330000.0    0

How to add scroll bar to the Relative Layout?

I used the

<ScrollView xmlns:android=""
android:layout_height="match_parent" >


and works perfectly

How to make war file in Eclipse

File -> Export -> Web -> WAR file

OR in Kepler follow as shown below :

enter image description here

JSON to TypeScript class instance?

You can now use Object.assign(target, ...sources). Following your example, you could use it like this:

class Foo {
  name: string;
  getName(): string { return };

let fooJson: string = '{"name": "John Doe"}';
let foo: Foo = Object.assign(new Foo(), JSON.parse(fooJson));

console.log(foo.getName()); //returns John Doe

Object.assign is part of ECMAScript 2015 and is currently available in most modern browsers.

git rm - fatal: pathspec did not match any files

git stash 

did the job, It restored the files that I had deleted using rm instead of git rm.

I did first a checkout of the last hash, but I do not believe it is required.

Clear listview content?

Call clear() method from your custom adapter .

Android setOnClickListener method - How does it work?

That what manual says about setOnClickListener method is:

public void setOnClickListener (View.OnClickListener l)

Added in API level 1 Register a callback to be invoked when this view is clicked. If this view is not clickable, it becomes clickable.


l View.OnClickListener: The callback that will run

And normally you have to use it like this

public class ExampleActivity extends Activity implements OnClickListener {
    protected void onCreate(Bundle savedValues) {
        Button button = (Button)findViewById(;

    // Implement the OnClickListener callback
    public void onClick(View v) {
      // do something when the button is clicked

Take a look at this lesson as well Building a Simple Calculator using Android Studio.

Is it possible to remove inline styles with jQuery?

you can create a jquery plugin like this :

jQuery.fn.removeInlineCss = (function(){
    var rootStyle =;
    var remover = 
        rootStyle.removeProperty    // modern browser
        || rootStyle.removeAttribute   // old browser (ie 6-8)
    return function removeInlineCss(properties){
        if(properties == null)
            return this.removeAttr('style');
        proporties = properties.split(/\s+/);
        return this.each(function(){
            for(var i = 0 ; i < proporties.length ; i++)
      , proporties[i]);


$(".foo").removeInlineCss(); //remove all inline styles
$(".foo").removeInlineCss("display"); //remove one inline style
$(".foo").removeInlineCss("color font-size font-weight"); //remove several inline styles

Using multiple parameters in URL in express

app.get('/fruit/:fruitName/:fruitColor', function(req, res) {
    var data = {
        "fruit": {
            "apple": req.params.fruitName,
            "color": req.params.fruitColor


If that doesn't work, try using console.log(req.params) to see what it is giving you.

Is there a way to delete created variables, functions, etc from the memory of the interpreter?

This worked for me.

You need to run it twice once for globals followed by locals

for name in dir():
    if not name.startswith('_'):
        del globals()[name]

for name in dir():
    if not name.startswith('_'):
        del locals()[name]

Changing image sizes proportionally using CSS?

transform: scale(0.5);


<div class="scaled">Scaled</div>
div {
  width: 80px;
  height: 80px;
  background-color: skyblue;

.scaled {
  transform: scale(0.7); /* Equal to scaleX(0.7) scaleY(0.7) */
  background-color: pink;


Can I change the headers of the HTTP request sent by the browser?

I would partially disagree with Milan's suggestion of embedding the requested representation in the URI.

If anyhow possible, URIs should only be used for addressing resources and not for tunneling HTTP methods/verbs. Eventually, specific business action (edit, lock, etc.) could be embedded in the URI if create (POST) or update (PUT) alone do not serve the purpose:


In the case of requesting a particular representation in URI you would need to disrupt your URI design eventually making it uglier, mixing two distinct REST concepts in the same place (i.e. URI) and making it harder to generically process requests on the server-side. What Milan is suggesting and many are doing the same, incl. Flickr, is exactly this.

Instead, a more RESTful approach would be using a separate place to encode preferred representation by using Accept HTTP header which is used for content negotiation where client tells to the server which content types it can handle/process and server tries to fulfill client's request. This approach is a part of HTTP 1.1 standard, software compliant and supported by web browsers as well.

Compare this:

GET /orders/08/165.xml HTTP/1.1
GET /orders/08/165&format=xml HTTP/1.1

to this:

GET /orders/08/165 HTTP/1.1
Accept: application/xml

From a web browser you can request any content type by using setRequestHeader method of XMLHttpRequest object. For example:

function getOrder(year, yearlyOrderId, contentType) {
 var client = new XMLHttpRequest();"GET", "/order/" + year + "/" + yearlyOrderId);
 client.setRequestHeader("Accept", contentType);

To sum it up: the address, i.e. the URI of a resource should be independent of its representation and XMLHttpRequest.setRequestHeader method allows you to request any representation using the Accept HTTP header.


JPA CriteriaBuilder - How to use "IN" comparison operator

If I understand well, you want to Join ScheduleRequest with User and apply the in clause to the userName property of the entity User.

I'd need to work a bit on this schema. But you can try with this trick, that is much more readable than the code you posted, and avoids the Join part (because it handles the Join logic outside the Criteria Query).

List<String> myList = new ArrayList<String> ();
for (User u : usersList) {
Expression<String> exp = scheduleRequest.get("createdBy");
Predicate predicate =;

In order to write more type-safe code you could also use Metamodel by replacing this line:

Expression<String> exp = scheduleRequest.get("createdBy");

with this:

Expression<String> exp = scheduleRequest.get(ScheduleRequest_.createdBy);

If it works, then you may try to add the Join logic into the Criteria Query. But right now I can't test it, so I prefer to see if somebody else wants to try.

Not a perfect answer though may be code snippets might help.

public <T> List<T> findListWhereInCondition(Class<T> clazz,
            String conditionColumnName, Serializable... conditionColumnValues) {
        QueryBuilder<T> queryBuilder = new QueryBuilder<T>(clazz);
        addWhereInClause(queryBuilder, conditionColumnName,
        return queryBuilder.getResultList();


private <T> void addWhereInClause(QueryBuilder<T> queryBuilder,
            String conditionColumnName, Serializable... conditionColumnValues) {

        Path<Object> path = queryBuilder.root.get(conditionColumnName);
        In<Object> in =;
        for (Serializable conditionColumnValue : conditionColumnValues) {


Error in Python IOError: [Errno 2] No such file or directory: 'data.csv'

It's looking for the file in the current directory.

First, go to that directory

cd /users/gcameron/Desktop/map

And then try to run it


How to copy a file to multiple directories using the gnu cp command

No, cp can copy multiple sources but will only copy to a single destination. You need to arrange to invoke cp multiple times - once per destination - for what you want to do; using, as you say, a loop or some other tool.

How to generate Javadoc from command line

its simple go to the folder where your all java code is saved say E:/javaFolder and then javadoc *.java


E:\javaFolder> javadoc *.java

SQL Server JOIN missing NULL values

Use Left Outer Join instead of Inner Join to include rows with NULLS.

SELECT Table1.Col1, Table1.Col2, Table1.Col3, Table2.Col4
    Table2 ON Table1.Col1 = Table2.Col1 
    AND Table1.Col2 = Table2.Col2

For more information, see here:


  1. PYTHONPATH is an environment variable
  2. Yes (see
  3. /usr/lib/python2.7 on Ubuntu
  4. you shouldn't install packages manually. Instead, use pip. When a package isn't in pip, it usually has a setuptools setup script which will install the package into the proper location (see point 3).
  5. if you use pip or setuptools, then you don't need to set PYTHONPATH explicitly

If you look at the instructions for pyopengl, you'll see that they are consistent with points 4 and 5.

What is a Maven artifact?

Q. What is Artifact in maven?
ANS: ARTIFACT is a JAR,(WAR or EAR), but it could be also something else. Each artifact has,

  • a group ID (like com.your.package),
  • an artifact ID (just a name), and
  • a version string.
    The three together uniquely identify the artifact.

Q.Why does Maven need them?
Ans: Maven is used to make them available for our applications.

How do I add a Font Awesome icon to input field?

simple way for new font awesome

  <div class="input-group">
                    <input type="text" class="form-control" placeholder="Search" name="txtSearch"  >
                    <div class="input-group-btn">
                        <button class="btn btn-default" type="submit"><i class="fas fa-search"></i></button>

Center the nav in Twitter Bootstrap

.navbar-right { 
    max-width :40%;   
    float:none !important;

just copy this code and change max-width as you like

How can I enable the Windows Server Task Scheduler History recording?

I think the confusion is that on my server I had to right click the Task Scheduler Library on left hand side and right click to get the option to enable or disable all tasks history.

Hope this helps

How to count the occurrence of certain item in an ndarray?

For your case you could also look into numpy.bincount

In [56]: a = np.array([0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1])

In [57]: np.bincount(a)
Out[57]: array([8, 4])  #count of zeros is at index 0 : 8
                        #count of ones is at index 1 : 4

How to pass parameter to function using in addEventListener?

In the first line of your JS code:

select.addEventListener('change', getSelection(this), false);

you're invoking getSelection by placing (this) behind the function reference. That is most likely not what you want, because you're now passing the return value of that call to addEventListener, instead of a reference to the actual function itself.

In a function invoked by addEventListener the value for this will automatically be set to the object the listener is attached to, productLineSelect in this case.

If that is what you want, you can just pass the function reference and this will in this example be select in invocations from addEventListener:

select.addEventListener('change', getSelection, false);

If that is not what you want, you'd best bind your value for this to the function you're passing to addEventListener:

var thisArg = { custom: 'object' };
select.addEventListener('change', getSelection.bind(thisArg), false);

The .bind part is also a call, but this call just returns the same function we're calling bind on, with the value for this inside that function scope fixed to thisArg, effectively overriding the dynamic nature of this-binding.

To get to your actual question: "How to pass parameters to function in addEventListener?"

You would have to use an additional function definition:

var globalVar = 'global';

productLineSelect.addEventListener('change', function(event) {
    var localVar = 'local';
    getSelection(event, this, globalVar, localVar);
}, false);

Now we pass the event object, a reference to the value of this inside the callback of addEventListener, a variable defined and initialised inside that callback, and a variable from outside the entire addEventListener call to your own getSelection function.

We also might again have an object of our choice to be this inside the outer callback:

var thisArg = { custom: 'object' };
var globalVar = 'global';

productLineSelect.addEventListener('change', function(event) {
    var localVar = 'local';
    getSelection(event, this, globalVar, localVar);
}.bind(thisArg), false);

Combining a class selector and an attribute selector with jQuery

This will also work:

$(".myclass[reference='12345']").css('border', '#000 solid 1px');

php mysqli_connect: authentication method unknown to the client [caching_sha2_password]

Like many many people, I have had the same problem. Although the user is set to use mysql_native_password, and I can connect from the command line, the only way I could get mysqli() to connect is to add


to the [mysqld] section of, in my setup on ubuntu 19.10, /etc/mysql/mysql.conf.d/mysqld.cnf

IntelliJ how to zoom in / out

Update: This answer is old. Intellij has since added actions to adjust font size. Check out Wilker's answer for assigning the new actions to keymaps.

Try Ctrl+Mouse Wheel which can be enabled under File > Settings... > Editor > General : Change font size (Zoom) with Ctrl+Mouse Wheel

What is the boundary in multipart/form-data?

The exact answer to the question is: yes, you can use an arbitrary value for the boundary parameter, given it does not exceed 70 bytes in length and consists only of 7-bit US-ASCII (printable) characters.

If you are using one of multipart/* content types, you are actually required to specify the boundary parameter in the Content-Type header, otherwise the server (in the case of an HTTP request) will not be able to parse the payload.

You probably also want to set the charset parameter to UTF-8 in your Content-Type header, unless you can be absolutely sure that only US-ASCII charset will be used in the payload data.

A few relevant excerpts from the RFC2046:

  • 4.1.2. Charset Parameter:

    Unlike some other parameter values, the values of the charset parameter are NOT case sensitive. The default character set, which must be assumed in the absence of a charset parameter, is US-ASCII.

  • 5.1. Multipart Media Type

    As stated in the definition of the Content-Transfer-Encoding field [RFC 2045], no encoding other than "7bit", "8bit", or "binary" is permitted for entities of type "multipart". The "multipart" boundary delimiters and header fields are always represented as 7bit US-ASCII in any case (though the header fields may encode non-US-ASCII header text as per RFC 2047) and data within the body parts can be encoded on a part-by-part basis, with Content-Transfer-Encoding fields for each appropriate body part.

    The Content-Type field for multipart entities requires one parameter, "boundary". The boundary delimiter line is then defined as a line consisting entirely of two hyphen characters ("-", decimal value 45) followed by the boundary parameter value from the Content-Type header field, optional linear whitespace, and a terminating CRLF.

    Boundary delimiters must not appear within the encapsulated material, and must be no longer than 70 characters, not counting the two leading hyphens.

    The boundary delimiter line following the last body part is a distinguished delimiter that indicates that no further body parts will follow. Such a delimiter line is identical to the previous delimiter lines, with the addition of two more hyphens after the boundary parameter value.

Here is an example using an arbitrary boundary:

Content-Type: multipart/form-data; charset=utf-8; boundary="another cool boundary"

--another cool boundary
Content-Disposition: form-data; name="foo"

--another cool boundary
Content-Disposition: form-data; name="baz"

--another cool boundary--

C Programming: How to read the whole file contents into a buffer

A portable solution could use getc.

#include <stdio.h>

char buffer[MAX_FILE_SIZE];
size_t i;

for (i = 0; i < MAX_FILE_SIZE; ++i)
    int c = getc(fp);

    if (c == EOF)
        buffer[i] = 0x00;

    buffer[i] = c;

If you don't want to have a MAX_FILE_SIZE macro or if it is a big number (such that buffer would be to big to fit on the stack), use dynamic allocation.

What's the difference between 'r+' and 'a+' when open file in python?

Python opens files almost in the same way as in C:

  • r+ Open for reading and writing. The stream is positioned at the beginning of the file.

  • a+ Open for reading and appending (writing at end of file). The file is created if it does not exist. The initial file position for reading is at the beginning of the file, but output is appended to the end of the file (but in some Unix systems regardless of the current seek position).

VB.Net .Clear() or txtbox.Text = "" textbox clear methods

The two methods are 100% equivalent.

I’m not sure why Microsoft felt the need to include this extra Clear method but since it’s there, I recommend using it, as it clearly expresses its purpose.

Forward declaring an enum in C++

Seems it can not be forward-declared in GCC!

Interesting discussion here

How to do joins in LINQ on multiple fields in single join

var result = from x in entity
   join y in entity2 on new { x.field1, x.field2 } equals new { y.field1, y.field2 }

Tomcat: How to find out running tomcat version

execute the script in your tomcat/bin directory:

sh tomcat/bin/

Server version: Apache Tomcat/7.0.42
Server built:   Jul 2 2013 08:57:41
Server number:
OS Name:        Linux
OS Version:     2.6.32-042stab084.26
Architecture:   amd64
JVM Version:    1.7.0_21-b11
JVM Vendor:     Oracle Corporation

jQuery Get Selected Option From Dropdown

$('#aioConceptName option:selected').val();

Switch statement equivalent in Windows batch file

I guess all other options would be more cryptic. For those who like readable and non-cryptic code:

IF        "%ID%"=="0" (
    REM do something

) ELSE IF "%ID%"=="1" (
    REM do something else

) ELSE IF "%ID%"=="2" (
    REM do another thing

) ELSE (
    REM default case...

It's like an anecdote:

Magician: Put the egg under the hat, do the magic passes ... Remove the hat and ... get the same egg but in the side view ...

The IF ELSE solution isn't that bad. It's almost as good as python's if elif else. More cryptic 'eggs' can be found here.

How to upgrade safely php version in wamp server

For someone who need to update the PHP version in WAMP, I can recommend this

I had a problems with updating too, but on this website are Wampserver addons like new php version (php 7.1.4 etc.) And you don't have to manually edit files like php.ini or phpForApache.


How to get last month/year in java?

private static String getPreviousMonthDate(Date date){
    final SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");

    Calendar cal = Calendar.getInstance();  
    cal.set(Calendar.DAY_OF_MONTH, 1);  
    cal.add(Calendar.DATE, -1);

    Date preMonthDate = cal.getTime();  
    return format.format(preMonthDate);

private static String getPreToPreMonthDate(Date date){
    final SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");

    Calendar cal = Calendar.getInstance();  
    cal.add(Calendar.MONTH, -1);  
    cal.add(Calendar.DATE, -1);  

    Date preToPreMonthDate = cal.getTime();  
    return format.format(preToPreMonthDate);

Change the class from factor to numeric of many columns in a data frame

I think that ucfagls found why your loop is not working.

In case you still don't want use a loop here is solution with lapply:

factorToNumeric <- function(f) as.numeric(levels(f))[as.integer(f)] 
cols <- c(1, 3:ncol(stats))
stats[cols] <- lapply(stats[cols], factorToNumeric)

Edit. I found simpler solution. It seems that as.matrix convert to character. So

stats[cols] <- as.numeric(as.matrix(stats[cols]))

should do what you want.

Any way to generate ant build.xml file automatically from Eclipse?

  • Select File > Export from main menu (or right click on the project name and select Export > Export…).
  • In the Export dialog, select General > Ant Buildfiles as follows: enter image description here

  • Click Next. In the Generate Ant Buildfilesscreen:

    • Check the project in list.
    • Uncheck the option "Create target to compile project using Eclipse compiler" - because we want to create a build file which is independent of Eclipse.
    • Leave the Name for Ant buildfile as default: build.xml

enter image description here

  • Click Finish, Eclipse will generate the build.xml file under project’s directory as follows:
    enter image description here
  • Double click on the build.xml file to open its content in Ant editor: enter image description here


Undoing a git rebase

git reset --hard origin/{branchName}

is the correct solution to reset all your local changes done by rebase.

How to add a recyclerView inside another recyclerView

you can use LayoutInflater to inflate your dynamic data as a layout file.

UPDATE : first create a LinearLayout inside your CardView's layout and assign an ID for it. after that create a layout file that you want to inflate. at last in your onBindViewHolder method in your "RAdaper" class. write these codes :

  mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

  view = mInflater.inflate(R.layout.my_list_custom_row, parent, false);

after that you can initialize data and ClickListeners with your RAdapter Data. hope it helps.

this and this may useful :)

URLEncoder not able to translate space character

If you want to encode URI path components, you can also use standard JDK functions, e.g.

public static String encodeURLPathComponent(String path) {
    try {
        return new URI(null, null, path, null).toASCIIString();
    } catch (URISyntaxException e) {
        // do some error handling
    return "";

The URI class can also be used to encode different parts of or whole URIs.

How to add class active on specific li on user click with jQuery

//Write a javascript method to bind click event of each "li" item

    function BindClickEvent()
    var selector = '.nav li';
    //Removes click event of each li
    $(selector ).unbind('click');
    //Add click event
    $(selector ).bind('click', function()


//first call this method when first time when page load

    $( document ).ready(function() {

//Call BindClickEvent method from server side

    protected void Page_Load(object sender, EventArgs e)
        ScriptManager.RegisterStartupScript(Page,GetType(), Guid.NewGuid().ToString(),"BindClickEvent();",true);

How can I easily add storage to a VirtualBox machine with XP installed?

The problem is that the file system on that disk was created when the disk had a certain geometry and you must modify it (while your OS is running on it).

So yes, making the virtual hard disk bigger is not a big issue. The issue is to make the new space available to your OS. To do that, you need tools like parted (Linux) or Partition Magic (Windows).

JavaScript: Difference between .forEach() and .map()

Performance Analysis For loops performs faster than map or foreach as number of elements in a array increases.

let array = [];
for (var i = 0; i < 20000000; i++) {

console.time('map'); => {
  return num * 4;

array.forEach((num, index) => {
  return array[index] = num * 4;

for (i = 0; i < array.length; i++) {
  array[i] = array[i] * 2;


can we use xpath with BeautifulSoup?

from lxml import etree
from bs4 import BeautifulSoup
soup = BeautifulSoup(open('path of your localfile.html'),'html.parser')
dom = etree.HTML(str(soup))
print dom.xpath('//*[@id="BGINP01_S1"]/section/div/font/text()')

Above used the combination of Soup object with lxml and one can extract the value using xpath

getResources().getColor() is deprecated

well it's deprecated in android M so you must make exception for android M and lower. Just add current theme on getColor function. You can get current theme with getTheme().

This will do the trick in fragment, you can replace getActivity() with getBaseContext(), yourContext, etc which hold your current context

    yourTitle.setTextColor(getActivity().getResources().getColor(android.R.color.white, getActivity().getTheme()));
}else {

*p.s : color is deprecated in M, but drawable is deprecated in L

Fixed page header overlaps in-page anchors

<div style="position:relative; top:-45px;">
    <a name="fragment"> </a>

This code should do the trick. Swap out 45px for the height of your header bar.

EDIT: If using jQuery is an option, I've also been successful using jQuery.localScroll with an offset value set. The offset option is a part of jQuery.scrollTo, which jQuery.localScroll is built upon. A demo is available here: (second window, under 'offset')

Running AngularJS initialization code when view is loaded

When your view loads, so does its associated controller. Instead of using ng-init, simply call your init() method in your controller:

$scope.init = function () {
    if ($routeParams.Id) {
        //get an existing object
    } else {
        //create a new object
    $scope.isSaving = false;

Since your controller runs before ng-init, this also solves your second issue.


As John David Five mentioned, you might not want to attach this to $scope in order to make this method private.

var init = function () {
    // do something

See jsFiddle

If you want to wait for certain data to be preset, either move that data request to a resolve or add a watcher to that collection or object and call your init method when your data meets your init criteria. I usually remove the watcher once my data requirements are met so the init function doesnt randomly re-run if the data your watching changes and meets your criteria to run your init method.

var init = function () {
    // do something
var unwatch = scope.$watch('myCollecitonOrObject', function(newVal, oldVal){
                    if( newVal && newVal.length > 0) {

Working with $scope.$emit and $scope.$on

The Easiest way :


  <div ng-app="myApp" ng-controller="myCtrl"> 

        <button ng-click="sendData();"> Send Data </button>



        var app = angular.module('myApp', []);
        app.controller('myCtrl', function($scope, $rootScope) {
            function sendData($scope) {
                var arrayData = ['sam','rumona','cubby'];
                $rootScope.$emit('someEvent', arrayData);

        app.controller('yourCtrl', function($scope, $rootScope) {
            $rootScope.$on('someEvent', function(event, data) {

How to execute my SQL query in CodeIgniter

$this->db->select('id, name, price, author, category, language, ISBN, publish_date');


How to convert an array of key-value tuples into an object

When I used the reduce function with acc[i] = cur; it returned a kind of object that I needed to access it like a array using this way obj[i].property. But using this way I have the Object that I wanted and I now can access it like

 function convertArraytoObject(arr) {
        var obj = arr.reduce(function (acc, cur, i) {
            acc = cur;
            return acc;
        }, {});
        return obj;

How to set zoom level in google map

For zooming your map two level then just add this small code of line map.setZoom(map.getZoom() + 2);

In JavaScript can I make a "click" event fire programmatically for a file input element?

Here is solution that work for me: CSS:

#uploadtruefield {
    left: 225px;
    opacity: 0;
    position: absolute;
    right: 0;
    top: 266px;
    width: 270px;
    z-index: 2;

.uploadmask {
    background:url(../img/browse.gif) no-repeat 100% 50%;

HTML with "small" JQuery help:

<div class="uploadmask">
    <input id="uploadmaskfield" type="text" name="uploadmaskfield">
<input id="uploadtruefield"  type="file" onchange="$('#uploadmaskfield').val(this.value)" >

Just be sure that maskfied is covered compeltly by true upload field.

JavaScript set object key by variable

You need to make the object first, then use [] to set it.

var key = "happyCount";
var obj = {};
obj[key] = someValueArray;

UPDATE 2018:

If you're able to use ES6 and Babel, you can use this new feature:

    [yourKeyVariable]: someValueArray,

How to view user privileges using windows cmd?

I'd start with:

secedit /export /areas USER_RIGHTS /cfg OUTFILE.CFG

Then examine the line for the relevant privilege. However, the problem now is that the accounts are listed as SIDs, not usernames.

Python copy files to a new directory and rename if file name already exists

For me shutil.copy is the best:

import shutil

#make a copy of the invoice to work with

You can change the path of the files as you want.

How do I assert my exception message with JUnit Test annotation?

If using @Rule, the exception set is applied to all the test methods in the Test class.

List files recursively in Linux CLI with path relative to the current directory

Use tree, with -f (full path) and -i (no indentation lines):

tree -if --noreport .
tree -if --noreport directory/

You can then use grep to filter out the ones you want.

If the command is not found, you can install it:

Type following command to install tree command on RHEL/CentOS and Fedora linux:

# yum install tree -y

If you are using Debian/Ubuntu, Mint Linux type following command in your terminal:

$ sudo apt-get install tree -y

What is the path that Django uses for locating and loading templates?

In django 3.1, go to setting of your project and import os

        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(BASE_DIR, "templates")],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [

AngularJS error: 'argument 'FirstCtrl' is not a function, got undefined'

remove ng-app="" from

<div ng-app="">

and simply make it


C# IPAddress from string

You've probably miss-typed something above that bit of code or created your own class called IPAddress. If you're using the .net one, that function should be available.

Have you tried using System.Net.IPAddress just in case?

System.Net.IPAddress ipaddress = System.Net.IPAddress.Parse("");  // as an example

The docs on Microsoft's site have a complete example which works fine on my machine.

What is jQuery Unobtrusive Validation?

With the unobtrusive way:

  • You don't have to call the validate() method.
  • You specify requirements using data attributes (data-val, data-val-required, etc.)

Jquery Validate Example:

<input type="text" name="email" class="required">
        $(function () {

Jquery Validate Unobtrusive Example:

<input type="text" name="email" data-val="true" 
data-val-required="This field is required.">  

<div class="validation-summary-valid" data-valmsg-summary="true">
    <ul><li style="display:none"></li></ul>

How to change value of a request parameter in laravel

Use add

$request->request->add(['img' => $img]);

NameError: name 'python' is not defined

It looks like you are trying to start the Python interpreter by running the command python.

However the interpreter is already started. It is interpreting python as a name of a variable, and that name is not defined.

Try this instead and you should hopefully see that your Python installation is working as expected:

print("Hello world!")

What does body-parser do with express?

To handle HTTP POST request in Express.js version 4 and above, you need to install middleware module called body-parser.

body-parser extract the entire body portion of an incoming request stream and exposes it on req.body.

The middleware was a part of Express.js earlier but now you have to install it separately.

This body-parser module parses the JSON, buffer, string and URL encoded data submitted using HTTP POST request. Install body-parser using NPM as shown below.

npm install body-parser --save

edit in 2019-april-2: in [email protected] the body-parser middleware bundled with express. for more details see this

What is a typedef enum in Objective-C?

A typedef allows the programmer to define one Objective-C type as another. For example,

typedef int Counter; defines the type Counter to be equivalent to the int type. This drastically improves code readability.

Java Garbage Collection Log messages

I just wanted to mention that one can get the detailed GC log with the


parameter. Then you see the PSYoungGen or PSPermGen output like in the answer.

Also -Xloggc:gc.log seems to generate the same output like -verbose:gc but you can specify an output file in the first.

Example usage:

java -Xloggc:./memory.log -XX:+PrintGCDetails Memory

To visualize the data better you can try gcviewer (a more recent version can be found on github).

Take care to write the parameters correctly, I forgot the "+" and my JBoss would not start up, without any error message!

No Application Encryption Key Has Been Specified

I actually had to add a .env file to my project and then copy the contents of .env.example so that the key:generate would work. Not sure why a .env file was not created when I started the project.

Laravel 5 error SQLSTATE[HY000] [1045] Access denied for user 'homestead'@'localhost' (using password: YES)

I was facing the same issue. Everything was fine but in


always had the incomplete password. Upon digging further, realized that the password had '#' character in it and that was getting dropped. As '#' is used to mark a line as a comment.

Programmatically set the initial view controller using Storyboards

You can set initial view controller using Interface Builder as well as programmatically.

Below is approach used for programmatically.

Objective-C :

        self.window = [[UIWindow alloc] initWithFrame:UIScreen.mainScreen.bounds];
        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];

        UIViewController *viewController = [storyboard instantiateViewControllerWithIdentifier:@"HomeViewController"]; // <storyboard id>

        self.window.rootViewController = viewController;
        [self.window makeKeyAndVisible];

        return YES;

Swift :

        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)

        var objMainViewController: MainViewController = mainStoryboard.instantiateViewControllerWithIdentifier("MainController") as! MainViewController

        self.window?.rootViewController = objMainViewController


        return true

Plotting time in Python with Matplotlib

7 years later and this code has helped me. However, my times still were not showing up correctly.

enter image description here

Using Matplotlib 2.0.0 and I had to add the following bit of code from Editing the date formatting of x-axis tick labels in matplotlib by Paul H.

import matplotlib.dates as mdates
myFmt = mdates.DateFormatter('%d')

I changed the format to (%H:%M) and the time displayed correctly. enter image description here

All thanks to the community.

How to get the request parameters in Symfony 2?

public function indexAction(Request $request)
   $data = $request->get('corresponding_arg');
   // this also works
   $data1 = $request->query->get('corresponding_arg1');

Using reflection in Java to create a new instance with the reference variable type set to the new instance class name?

You want to be able to pass in a Class and get a type-safe instance of that class? Try the following:

public static void main(String [] args) throws Exception {
    String s = instanceOf(String.class);

public static <T> T instanceOf (Class<T> clazz) throws Exception {
    return clazz.newInstance();

error C2220: warning treated as error - no 'object' file generated

As a side-note, you can enable/disable individual warnings using #pragma. You can have a look at the documentation here

From the documentation:

// pragma_warning.cpp
// compile with: /W1
#pragma warning(disable:4700)
void Test() {
   int x;
   int y = x;   // no C4700 here
   #pragma warning(default:4700)   // C4700 enabled after Test ends

int main() {
   int x;
   int y = x;   // C4700

Connect to external server by using phpMyAdmin

at version 4.0 or above, we need to create one '' or rename the '' to '';

In my case, I also work with one mysql server for each environment (dev and production):

/* others code*/  
$whoIam = gethostname();
switch($whoIam) {
    case 'devHost':
        $cfg['Servers'][$i]['host'] = 'localhost';
    case 'MasterServer':
        $cfg['Servers'][$i]['host'] = 'masterMysqlServer';
} /* others code*/ 

Java - How to find the redirected url of a url?

I'd actually suggest using a solid open-source library as an http client. If you take a look at http client by ASF you'll find life a lot easier. It is an easy-to-use,scalable and robust client for http.

How to remove a file from the index in git?

This should unstage a <file> for you (without removing or otherwise modifying the file):

git reset <file>

Colouring plot by factor in R

There are two ways that I know of to color plot points by factor and then also have a corresponding legend automatically generated. I'll give examples of both:

  1. Using ggplot2 (generally easier)
  2. Using R's built in plotting functionality in combination with the colorRampPallete function (trickier, but many people prefer/need R's built-in plotting facilities)

For both examples, I will use the ggplot2 diamonds dataset. We'll be using the numeric columns diamond$carat and diamond$price, and the factor/categorical column diamond$color. You can load the dataset with the following code if you have ggplot2 installed:


Using ggplot2 and qplot

It's a one liner. Key item here is to give qplot the factor you want to color by as the color argument. qplot will make a legend for you by default.

  x = carat,
  y = price,
  data = diamonds,
  color = diamonds$color # color by factor color (I know, confusing)

Your output should look like this: qplot output colored by factor "diamond$color"

Using R's built in plot functionality

Using R's built in plot functionality to get a plot colored by a factor and an associated legend is a 4-step process, and it's a little more technical than using ggplot2.

First, we will make a colorRampPallete function. colorRampPallete() returns a new function that will generate a list of colors. In the snippet below, calling color_pallet_function(5) would return a list of 5 colors on a scale from red to orange to blue:

color_pallete_function <- colorRampPalette(
  colors = c("red", "orange", "blue"),
  space = "Lab" # Option used when colors do not represent a quantitative scale

Second, we need to make a list of colors, with exactly one color per diamond color. This is the mapping we will use both to assign colors to individual plot points, and to create our legend.

num_colors <- nlevels(diamonds$color)
diamond_color_colors <- color_pallet_function(num_colors)

Third, we create our plot. This is done just like any other plot you've likely done, except we refer to the list of colors we made as our col argument. As long as we always use this same list, our mapping between colors and diamond$colors will be consistent across our R script.

  x = diamonds$carat,
  y = diamonds$price,
  xlab = "Carat",
  ylab = "Price",
  pch = 20, # solid dots increase the readability of this data plot
  col = diamond_color_colors[diamonds$color]

Fourth and finally, we add our legend so that someone reading our graph can clearly see the mapping between the plot point colors and the actual diamond colors.

  x ="topleft",
  legend = paste("Color", levels(diamonds$color)), # for readability of legend
  col = diamond_color_colors,
  pch = 19, # same as pch=20, just smaller
  cex = .7 # scale the legend to look attractively sized

Your output should look like this: standard R plot output colored by factor "diamond$color"

Nifty, right?

vuetify center items into v-flex

<v-layout justify-center>
    <v-btn primary>
    </v-btn>`enter code here`

How do I set the version information for an existing .exe, .dll?

Or you could check out the freeware StampVer for Win32 exe/dll files.
It will only change the file and product versions though if they have a version resource already. It cannot add a version resource if one doesn’t exist.

Using regular expression in css?

You can manage selecting those elements without any form of regex as the previous answers show, but to answer the question directly, yes you can use a form of regex in selectors:

#sections div[id^='s'] {
    color: red;  

That says select any div elements inside the #sections div that have an ID starting with the letter 's'.

See fiddle here.

W3 CSS selector docs here.

appending list but error 'NoneType' object has no attribute 'append'

When doing pan_list.append(p.last) you're doing an inplace operation, that is an operation that modifies the object and returns nothing (i.e. None).

You should do something like this :

if p.last_name==None or p.last_name=="": 
last_list.append(p.last)  # Here I modify the last_list, no affectation
print last_list

Cannot uninstall angular-cli

You have to use (without @)

npm uninstall -g angular/cli


If you're using Angular CLI beta.28 or less, you need to uninstall angular-cli package. It should be done due to changing of package's name and scope from angular-cli to @angular/cli

How to Install Sublime Text 3 using Homebrew

As per latest updates, caskroom packages have moved to homebrew. So try following commands:

brew tap homebrew/cask
brew cask install sublime-text

These 2 terminal commands will be enough for installing sublime.

Best way to strip punctuation from a string

Try that one :)

regex.sub(r'\p{P}','', s)

Error:Execution failed for task ':app:transformClassesWithJarMergingForDebug'

see if their duplicate jars or dependencies your adding remove it and your error will be gone: Eg: if you add android:supportv4 jar and also dependency you will get the error so remove the jar error will be gone

convert epoch time to date

Please take care that the epoch time is in second and Date object accepts Long value which is in milliseconds. Hence you would have to multiply epoch value with 1000 to use it as long value . Like below :-

SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddhhmmss");
Long dateLong=Long.parseLong(sdf.format(epoch*1000));

How to properly and completely close/reset a TcpClient connection?

Except for some internal logging, Close == Dispose.

Dispose calls tcpClient.Client.Shutdown( SocketShutdown.Both ), but its eats any errors. Maybe if you call it directly, you can get some useful exception information.

What is the most robust way to force a UIView to redraw?

The money-back guaranteed, reinforced-concrete-solid way to force a view to draw synchronously (before returning to the calling code) is to configure the CALayer's interactions with your UIView subclass.

In your UIView subclass, create a displayNow() method that tells the layer to “set course for display” then to “make it so”:


/// Redraws the view's contents immediately.
/// Serves the same purpose as the display method in GLKView.
public func displayNow()
    let layer = self.layer


/// Redraws the view's contents immediately.
/// Serves the same purpose as the display method in GLKView.
- (void)displayNow
    CALayer *layer = self.layer;
    [layer setNeedsDisplay];
    [layer displayIfNeeded];

Also implement a draw(_: CALayer, in: CGContext) method that'll call your private/internal drawing method (which works since every UIView is a CALayerDelegate):


/// Called by our CALayer when it wants us to draw
///     (in compliance with the CALayerDelegate protocol).
override func draw(_ layer: CALayer, in context: CGContext)


/// Called by our CALayer when it wants us to draw
///     (in compliance with the CALayerDelegate protocol).
- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)context
    [self internalDrawWithRect:self.bounds];

And create your custom internalDraw(_: CGRect) method, along with fail-safe draw(_: CGRect):


/// Internal drawing method; naming's up to you.
func internalDraw(_ rect: CGRect)
    // @FILLIN: Custom drawing code goes here.
    //  (Use `UIGraphicsGetCurrentContext()` where necessary.)

/// For compatibility, if something besides our display method asks for draw.
override func draw(_ rect: CGRect) {


/// Internal drawing method; naming's up to you.
- (void)internalDrawWithRect:(CGRect)rect
    // @FILLIN: Custom drawing code goes here.
    //  (Use `UIGraphicsGetCurrentContext()` where necessary.)

/// For compatibility, if something besides our display method asks for draw.
- (void)drawRect:(CGRect)rect {
    [self internalDrawWithRect:rect];

And now just call myView.displayNow() whenever you really-really need it to draw (such as from a CADisplayLink callback).  Our displayNow() method will tell the CALayer to displayIfNeeded(), which will synchronously call back into our draw(_:,in:) and do the drawing in internalDraw(_:), updating the visual with what's drawn into the context before moving on.

This approach is similar to @RobNapier's above, but has the advantage of calling displayIfNeeded() in addition to setNeedsDisplay(), which makes it synchronous.

This is possible because CALayers expose more drawing functionality than UIViews do— layers are lower-level than views and designed explicitly for the purpose of highly-configurable drawing within the layout, and (like many things in Cocoa) are designed to be used flexibly (as a parent class, or as a delegator, or as a bridge to other drawing systems, or just on their own). Proper usage of the CALayerDelegate protocol makes all this possible.

More information about the configurability of CALayers can be found in the Setting Up Layer Objects section of the Core Animation Programming Guide.

Convert String to Uri

What are you going to do with the URI?

If you're just going to use it with an HttpGet for example, you can just use the string directly when creating the HttpGet instance.

HttpGet get = new HttpGet("");

cmake and libpthread

The following should be clean (using find_package) and work (the find module is called FindThreads):

cmake_minimum_required (VERSION 2.6) 
find_package (Threads)
add_executable (myapp main.cpp ...)
target_link_libraries (myapp ${CMAKE_THREAD_LIBS_INIT})

How to hide close button in WPF window?

If the need is only to prohibit the user from closing the window, this is a simple solution.

XAML code: IsCloseButtonEnabled="False"

It's block the button.

Writing sqlplus output to a file

You may use the SPOOL command to write the information to a file.

Before executing any command type the following:

SPOOL <output file path>

All commands output following will be written to the output file.

To stop command output writing type


System.Data.SqlClient.SqlException: Invalid object name 'dbo.Projects'

The problem I had was because I had made a database in my LocalDb.
If that's the case then you have to write is as shown below:

    "SELECT * FROM <DatabaseName>.[dbo].[Projects]"

Replace with your database name.
You can probably also drop the "[ ]"

Printing out all the objects in array list

You have to define public String toString() method in your Student class. For example:

public String toString() {
  return "Student: " + studentName + ", " + studentNo;

How can I protect my .NET assemblies from decompilation?

If you want to fully protect your app from decompilation, look at Aladdin's Hasp. You can wrap your assemblies in an encrypted shell that can only be accessed by your application. Of course one wonders how they're able to do this but it works. I don't know however if they protect your app from runtime attachment/reflection which is what Crack.NET is able to do.

-- Edit Also be careful of compiling to native code as a solution...there are decompilers for native code as well.

Create file path from variables

You can also use an object-oriented path with pathlib (available as a standard library as of Python 3.4):

from pathlib import Path

start_path = Path('/my/root/directory')
final_path = start_path / 'in' / 'here'

What is the difference between git clone and checkout?

One thing to notice is the lack of any "Copyout" within git. That's because you already have a full copy in your local repo - your local repo being a clone of your chosen upstream repo. So you have effectively a personal checkout of everything, without putting some 'lock' on those files in the reference repo.

Git provides the SHA1 hash values as the mechanism for verifying that the copy you have of a file / directory tree / commit / repo is exactly the same as that used by whoever is able to declare things as "Master" within the hierarchy of trust. This avoids all those 'locks' that cause most SCM systems to choke (with the usual problems of private copies, big merges, and no real control or management of source code ;-) !

SQL SELECT everything after a certain character

Try this (it should work if there are multiple '=' characters in the string):

SELECT RIGHT(supplier_reference, (CHARINDEX('=',REVERSE(supplier_reference),0))-1) FROM ps_product

How to change Screen buffer size in Windows Command Prompt from batch script

I created the following utility to set the console size and scroll buffers.

I compiled it using DEV C++ (

An executable is included in

#include <iostream>
#include <windows.h> 

using namespace std;

// SetWindow(Width,Height,WidthBuffer,HeightBuffer) -- set console size and buffer dimensions
void SetWindow(int Width, int Height, int WidthBuffer, int HeightBuffer) { 
    _COORD coord; 
    coord.X = WidthBuffer; 
    coord.Y = HeightBuffer; 

    _SMALL_RECT Rect; 
    Rect.Top = 0; 
    Rect.Left = 0; 
    Rect.Bottom = Height - 1; 
    Rect.Right = Width - 1; 

    HANDLE Handle = GetStdHandle(STD_OUTPUT_HANDLE);      // Get Handle 
    SetConsoleScreenBufferSize(Handle, coord);            // Set Buffer Size 
    SetConsoleWindowInfo(Handle, TRUE, &Rect);            // Set Window Size 
}  // SetWindow

// main(Width,Height,WidthBuffer,HeightBuffer) -- main
int main(int argc, char *argv[]) {     
    int width = 80;
    int height = 25;
    int wbuffer = width + 200;
    int hbuffer = height + 1000;

    if ( argc == 5 ){
        width = atoi(argv[1]);
        height = atoi(argv[2]);
        wbuffer = atoi(argv[3]);
        hbuffer = atoi(argv[4]);
    } else if ( argc > 1 ) {
        cout << "Usage: " << argv[0] << " [ width height bufferwidth bufferheight ]" << endl << endl;
        cout << "  Where" << endl;
        cout << "    width            console width" << endl;
        cout << "    height           console height" << endl;
        cout << "    bufferwidth      scroll buffer width" << endl;
        cout << "    bufferheight     scroll buffer height" << endl;
        return 4;

    return 0;

A CORS POST request works from plain JavaScript, but why not with jQuery?

Cors change the request method before it's done, from POST to OPTIONS, so, your post data will not be sent. The way that worked to handle this cors issue, is performing the request with ajax, which does not support the OPTIONS method. example code:

            type: "POST",
            crossdomain: true,
            url: "http://localhost:1415/anything",
            dataType: "json",
            data: JSON.stringify({
                anydata1: "any1",
                anydata2: "any2",
            success: function (result) {
            error: function (xhr, status, err) {
                console.error(xhr, status, err);

with this headers on c# server:

                    if (request.HttpMethod == "OPTIONS")
                          response.AddHeader("Access-Control-Allow-Headers", "Content-Type, Accept, X-Requested-With");
                          response.AddHeader("Access-Control-Allow-Methods", "GET, POST");
                          response.AddHeader("Access-Control-Max-Age", "1728000");
                    response.AppendHeader("Access-Control-Allow-Origin", "*");

How to split a python string on new line characters

? Splitting line in Python:

Have you tried using str.splitlines() method?:

From the docs:


Return a list of the lines in the string, breaking at line boundaries. Line breaks are not included in the resulting list unless keepends is given and true.

For example:

>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()
['Line 1', '', 'Line 3', 'Line 4']

>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines(True)
['Line 1\n', '\n', 'Line 3\r', 'Line 4\r\n']

Which delimiters are considered?

This method uses the universal newlines approach to splitting lines.

The main difference between Python 2.X and Python 3.X is that the former uses the universal newlines approach to splitting lines, so "\r", "\n", and "\r\n" are considered line boundaries for 8-bit strings, while the latter uses a superset of it that also includes:

  • \v or \x0b: Line Tabulation (added in Python 3.2).
  • \f or \x0c: Form Feed (added in Python 3.2).
  • \x1c: File Separator.
  • \x1d: Group Separator.
  • \x1e: Record Separator.
  • \x85: Next Line (C1 Control Code).
  • \u2028: Line Separator.
  • \u2029: Paragraph Separator.

splitlines VS split:

Unlike str.split() when a delimiter string sep is given, this method returns an empty list for the empty string, and a terminal line break does not result in an extra line:

>>> ''.splitlines()

>>> 'Line 1\n'.splitlines()
['Line 1']

While str.split('\n') returns:

>>> ''.split('\n')

>>> 'Line 1\n'.split('\n')
['Line 1', '']

?? Removing additional whitespace:

If you also need to remove additional leading or trailing whitespace, like spaces, that are ignored by str.splitlines(), you could use str.splitlines() together with str.strip():

>>> [str.strip() for str in 'Line 1  \n  \nLine 3 \rLine 4 \r\n'.splitlines()]
['Line 1', '', 'Line 3', 'Line 4']

? Removing empty strings (''):

Lastly, if you want to filter out the empty strings from the resulting list, you could use filter():

>>> # Python 2.X:
>>> filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines())
['Line 1', 'Line 3', 'Line 4']

>>> # Python 3.X:
>>> list(filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()))
['Line 1', 'Line 3', 'Line 4']

Additional comment regarding the original question:

As the error you posted indicates and Burhan suggested, the problem is from the print. There's a related question about that could be useful to you: UnicodeEncodeError: 'charmap' codec can't encode - character maps to <undefined>, print function

What is the difference between a strongly typed language and a statically typed language?

Strong typing probably means that variables have a well-defined type and that there are strict rules about combining variables of different types in expressions. For example, if A is an integer and B is a float, then the strict rule about A+B might be that A is cast to a float and the result returned as a float. If A is an integer and B is a string, then the strict rule might be that A+B is not valid.

Static typing probably means that types are assigned at compile time (or its equivalent for non-compiled languages) and cannot change during program execution.

Note that these classifications are not mutually exclusive, indeed I would expect them to occur together frequently. Many strongly-typed languages are also statically-typed.

And note that when I use the word 'probably' it is because there are no universally accepted definitions of these terms. As you will already have seen from the answers so far.

What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function?

The first, curly braces. Otherwise, you run into consistency issues with keys that have odd characters in them, like =.

# Works fine.
a = {
    'a': 'value',
    'b=c': 'value',

# Eeep! Breaks if trying to be consistent.
b = dict( 

How to stop creating .DS_Store on Mac?

Put following line into your ".profile" file.

Open .profile file and copy this line

find ~/ -name '.DS_Store' -delete

When you open terminal window it will automatically delete your .DS_Store file for you.

Error : ORA-01704: string literal too long

To solve this issue on my side, I had to use a combo of what was already proposed there

  chunk1 CLOB; chunk2 CLOB; chunk3 CLOB;
  chunk1 := 'very long literal part 1';
  chunk2 := 'very long literal part 2';
  chunk3 := 'very long literal part 3';

  SELECT ( chunk1 || chunk2 || chunk3 ) FROM dual;

Hope this helps.

How to set the range of y-axis for a seaborn boxplot?

It is standard matplotlib.pyplot:

import matplotlib.pyplot as plt
plt.ylim(10, 40)

Or simpler, as mwaskom comments below:

ax.set(ylim=(10, 40))

enter image description here

How to vertically align into the center of the content of a div with defined width/height?

margin: all_four_margin

by providing 50% to all_four_margin will place the element at the center

style="margin: 50%"

you can apply it for following too

margin: top right bottom left

margin: top right&left bottom

margin: top&bottom right&left

by giving appropriate % we get the element wherever we want.

Create two blank lines in Markdown

You can do it perfectly using this:


When does SQLiteOpenHelper onCreate() / onUpgrade() run?

To further add missing points here, as per the request by Jaskey

Database version is stored within the SQLite database file.

catch is the constructor

SQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version)

So when the database helper constructor is called with a name (2nd param), platform checks if the database exists or not and if the database exists, it gets the version information from the database file header and triggers the right call back

As already explained in the older answer, if the database with the name doesn't exists, it triggers onCreate.

Below explanation explains onUpgrade case with an example.

Say, your first version of application had the DatabaseHelper (extending SQLiteOpenHelper) with constructor passing version as 1 and then you provided an upgraded application with the new source code having version passed as 2, then automatically when the DatabaseHelper is constructed, platform triggers onUpgrade by seeing the file already exists, but the version is lower than the current version which you have passed.

Now say you are planing to give a third version of application with db version as 3 (db version is increased only when database schema is to be modified). In such incremental upgrades, you have to write the upgrade logic from each version incrementally for a better maintainable code

Example pseudo code below:

public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
  switch(oldVersion) {
    case 1:
       //upgrade logic from version 1 to 2
    case 2:
       //upgrade logic from version 2 to 3
    case 3:
       //upgrade logic from version 3 to 4
       throw new IllegalStateException(
                "onUpgrade() with unknown oldVersion " + oldVersion);

Notice the missing break statement in case 1 and 2. This is what I mean by incremental upgrade.

Say if the old version is 2 and new version is 4, then the logic will upgrade the database from 2 to 3 and then to 4

If old version is 3 and new version is 4, it will just run the upgrade logic for 3 to 4

How to implement the ReLU function in Numpy

numpy didn't have the function of relu, but you define it by yourself as follow:

def relu(x):
    return np.maximum(0, x)

for example:

arr = np.array([[-1,2,3],[1,2,3]])

ret = relu(arr)
print(ret) # print [[0 2 3] [1 2 3]]

Word wrap for a label in Windows Forms

  1. Put the label inside a panel
  2. Handle the ClientSizeChanged event for the panel, making the label fill the space:

    private void Panel2_ClientSizeChanged(object sender, EventArgs e)
        label1.MaximumSize = new Size((sender as Control).ClientSize.Width - label1.Left, 10000);
  3. Set Auto-Size for the label to true

  4. Set Dock for the label to Fill

How to Convert datetime value to yyyymmddhhmmss in SQL server?

Since SQL Server Version 2012 you can use:

SELECT format(getdate(),'yyyyMMddHHmmssffff')

Combine multiple results in a subquery into a single comma-separated value

In MySQL there is a group_concat function that will return what you're asking for.

SELECT TableA.ID, TableA.Name, group_concat(TableB.SomeColumn) 
as SomColumnGroup FROM TableA LEFT JOIN TableB ON 
TableB.TableA_ID = TableA.ID

Default port for SQL Server

  1. The default SQL Server port is 1433 but only if it's a default install. Named instances get a random port number.

  2. The browser service runs on port UDP 1434.

  3. Reporting services is a web service - so it's port 80, or 443 if it's SSL enabled.

  4. Analysis services is 2382 but only if it's a default install. Named instances get a random port number.

Refer to a cell in another worksheet by referencing the current worksheet's name?

Here is how I made monthly page in similar manner as Fernando:

  1. I wrote manually on each page number of the month and named that place as ThisMonth. Note that you can do this only before you make copies of the sheet. After copying Excel doesn't allow you to use same name, but with sheet copy it does it still. This solution works also without naming.
  2. I added number of weeks in the month to location C12. Naming is fine also.
  3. I made five weeks on every page and on fifth week I made function


    that empties fifth week if this month has only four weeks. C12 holds the number of weeks.

  4. ...
  5. I created annual Excel, so I had 12 sheets in it: one for each month. In this example name of the sheet is "Month". Note that this solutions works also with the ODS file standard except you need to change all spaces as "_" characters.
  6. I renamed first "Month" sheet as "Month (1)" so it follows the same naming principle. You could also name it as "Month1" if you wish, but "January" would require a bit more work.
  7. Insert following function on the first day field starting sheet #2:

     =INDIRECT(CONCATENATE("'Month (",ThisMonth-1,")'!B15"))+INDIRECT(CONCATENATE("'Month (",ThisMonth-1,")'!C12"))*7

    So in another word, if you fill four or five weeks on the previous sheet, this calculates date correctly and continues from correct date.

Testing whether a value is odd or even

if (testNum == 0);
else if (testNum % 2  == 0);
else if ((testNum % 2) != 0 );

MySQL JOIN with LIMIT 1 on joined table

The With clause would do the trick. Something like this:

SELECT,, c.title FROM selection a JOIN categories c ON ( =;

How to change font size in Eclipse for Java text editors?

Press ctrl + - to decrease, and ctrl + + to increase the Font Size.

It's working for me in Eclipse Oxygen.

How to access cookies in AngularJS?

This answer has been updated to reflect latest stable angularjs version. One important note is that $cookieStore is a thin wrapper surrounding $cookies. They are pretty much the same in that they only work with session cookies. Although, this answers the original question, there are other solutions you may wish to consider such as using localstorage, or jquery.cookie plugin (which would give you more fine-grained control and do serverside cookies. Of course doing so in angularjs means you probably would want to wrap them in a service and use $scope.apply to notify angular of changes to models (in some cases).

One other note and that is that there is a slight difference between the two when pulling data out depending on if you used $cookie to store value or $cookieStore. Of course, you'd really want to use one or the other.

In addition to adding reference to the js file you need to inject ngCookies into your app definition such as:

angular.module('myApp', ['ngCookies']);

you should then be good to go.

Here is a functional minimal example, where I show that cookieStore is a thin wrapper around cookies:

<!DOCTYPE html>
<html ng-app="myApp">
   <link rel="stylesheet" type="text/css" href="//">
<body ng-controller="MyController">

  <h3>Cookie Store</h3>

  <script src="//"></script>
  <script src="//"></script>
    angular.module('myApp', ['ngCookies']);
                       function($scope,$cookies,$cookieStore) {
      var someSessionObj = { 'innerObj' : 'somesessioncookievalue'};

    $cookies.dotobject = someSessionObj;
    $scope.usingCookies = { 'cookies.dotobject' : $cookies.dotobject, "cookieStore.get" : $cookieStore.get('dotobject') };

    $cookieStore.put('obj', someSessionObj);
    $scope.usingCookieStore = { "cookieStore.get" : $cookieStore.get('obj'), 'cookies.dotobject' : $cookies.obj, };


The steps are:

  1. include angular.js
  2. include angular-cookies.js
  3. inject ngCookies into your app module (and make sure you reference that module in the ng-app attribute)
  4. add a $cookies or $cookieStore parameter to the controller
  5. access the cookie as a member variable using the dot (.) operator -- OR --
  6. access cookieStore using put/get methods

How can I remove an element from a list, with lodash?

Here is the simple lodash function with array and deleting it with the index number.

index_tobe_delete = 1

fruit = [{a: "apple"}, {b: "banana"}, {c: "choco"}]
_.filter(fruit, (value, key)=> {
return (key !== index_tobe_delete)

HRESULT: 0x80131040: The located assembly's manifest definition does not match the assembly reference

Just Check your webconfig file and remove this code :-

    <assemblyIdentity name="itextsharp" publicKeyToken="8354ae6d2174ddca" culture="neutral" />
    <bindingRedirect oldVersion="" newVersion="" />

Why is C so fast, and why aren't other languages as fast or faster?

With modern optimizing compilers, it's highly unlikely that a pure C program is going to be all that much faster than compiled .net code, if at all. With the productivity enhancement that frameworks like .net provide the developer, you can do things in a day that used to take weeks or months in regular C. Coupled with the cheap cost of hardware compared to a developer's salary, it's just WAY cheaper to write the stuff in a high-level language and throw hardware at any slowness.

The reason Jeff and Joel talk about C being the "real programmer" language is because there is no hand-holding in C. You must allocate your own memory, deallocate that memory, do your own bounds-checking, etc. There's no such thing as new object(); There's no garbage collection, classes, OOP, entity frameworks, LINQ, properties, attributes, fields, or anything like that. You have to know things like pointer arithmetic and how to dereference a pointer. And, for that matter, know and understand what a pointer is. You have to know what a stack frame is and what the instruction pointer is. You have to know the memory model of the CPU architecture you're working on. There is a lot of implicit understanding of the architecture of a microcomputer (usually the microcomputer you're working on) when programming in C that simply is not present nor necessary when programming in something like C# or Java. All of that information has been off-loaded to the compiler (or VM) programmer.

How long is the SHA256 hash?

I prefer to use BINARY(32) since it's the optimized way!

You can place in that 32 hex digits from (00 to FF).

Therefore BINARY(32)!

Access XAMPP Localhost from Internet

I guess you can do this in 5 minute without any further IP/port forwarding, for presenting your local websites temporary.

All you need to do it, go to Download small tool extract and run that tool as administrator enter image description here

Enter command
ngrok http 80

You will see it will connect to server and will create a temporary URL for you which you can share to your friend and let him browse localhost or any of its folder.

You can see detailed process here.
How do I access/share xampp or localhost website from another computer

Force unmount of NFS-mounted directory

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


The command for that is something roughly like:

ifconfig eth0:fakenfs netmask

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

ifconfig eth0:fakenfs down

FreeBSD and similar operating systems

The command would be something like:

ifconfig em0 alias netmask

And then to remove it:

ifconfig em0 delete

man ifconfig(8) for more!

What's the easiest way to install a missing Perl module?

I note some folks suggesting one run cpan under sudo. That used to be necessary to install into the system directory, but modern versions of the CPAN shell allow you to configure it to use sudo just for installing. This is much safer, since it means that tests don't run as root.

If you have an old CPAN shell, simply install the new cpan ("install CPAN") and when you reload the shell, it should prompt you to configure these new directives.

Nowadays, when I'm on a system with an old CPAN, the first thing I do is update the shell and set it up to do this so I can do most of my cpan work as a normal user.

Also, I'd strongly suggest that Windows users investigate strawberry Perl. This is a version of Perl that comes packaged with a pre-configured CPAN shell as well as a compiler. It also includes some hard-to-compile Perl modules with their external C library dependencies, notably XML::Parser. This means that you can do the same thing as every other Perl user when it comes to installing modules, and things tend to "just work" a lot more often.

Swift double to string

Swift 4: Use following code

let number = 2.4
let string = String(format: "%.2f", number)

How do I rename a column in a database table using SQL?

I think this is the easiest way to change column name.


Joining two lists together

As long as they are of the same type, it's very simple with AddRange:


Can a java lambda have more than 1 parameter?

You could also use jOOL library -

It has already prepared function interfaces with different number of parameters. For instance, you could use org.jooq.lambda.function.Function3, etc from Function0 up to Function16.

What is the fastest factorial function in JavaScript?

According to Wolfram MathWorld:

The factorial n! is defined for a positive integer n as


Therefore, you can use the following method to obtain the factorial of a number:

const factorial = n => +!n || n * factorial(--n);

factorial(4) // 4! = 4 * 3 * 2 * 1 = 24

Efficiently convert rows to columns in sql server

This is rather a method than just a single script but gives you much more flexibility.

First of all There are 3 objects:

  1. User defined TABLE type [ColumnActionList] -> holds data as parameter
  2. SP [proc_PivotPrepare] -> prepares our data
  3. SP [proc_PivotExecute] -> execute the script

CREATE TYPE [dbo].[ColumnActionList] AS TABLE ( [ID] [smallint] NOT NULL, [ColumnName] nvarchar NOT NULL, [Action] nchar NOT NULL ); GO

    CREATE PROCEDURE [dbo].[proc_PivotPrepare] 
    @DB_Name        nvarchar(128),
    @TableName      nvarchar(128)
            SELECT @DB_Name = ISNULL(@DB_Name,db_name())
    DECLARE @SQL_Code nvarchar(max)

    DECLARE @MyTab TABLE (ID smallint identity(1,1), [Column_Name] nvarchar(128), [Type] nchar(1), [Set Action SQL] nvarchar(max));

    SELECT @SQL_Code        =   'SELECT [<| SQL_Code |>] = '' '' '
                                        + 'UNION ALL '
                                        + 'SELECT ''----------------------------------------------------------------------------------------------------'' '
                                        + 'UNION ALL '
                                        + 'SELECT ''-----| Declare user defined type [ID] / [ColumnName] / [PivotAction] '' '
                                        + 'UNION ALL '
                                        + 'SELECT ''----------------------------------------------------------------------------------------------------'' '
                                        + 'UNION ALL '
                                        + 'SELECT ''DECLARE @ColumnListWithActions ColumnActionList;'''
                                        + 'UNION ALL '
                                        + 'SELECT ''----------------------------------------------------------------------------------------------------'' '
                                        + 'UNION ALL '
                                        + 'SELECT ''-----| Set [PivotAction] (''''S'''' as default) to select dimentions and values '' '
                                        + 'UNION ALL '
                                        + 'SELECT ''-----|'''
                                        + 'UNION ALL '
                                        + 'SELECT ''-----| ''''S'''' = Stable column || ''''D'''' = Dimention column || ''''V'''' = Value column '' '
                                        + 'UNION ALL '
                                        + 'SELECT ''----------------------------------------------------------------------------------------------------'' '
                                        + 'UNION ALL '
                                        + 'SELECT ''INSERT INTO  @ColumnListWithActions VALUES ('' + CAST( ROW_NUMBER() OVER (ORDER BY [NAME]) as nvarchar(10)) + '', '' + '''''''' + [NAME] + ''''''''+ '', ''''S'''');'''
                                        + 'FROM [' + @DB_Name + '].sys.columns  '
                                        + 'WHERE object_id = object_id(''[' + @DB_Name + ']..[' + @TableName + ']'') '
                                        + 'UNION ALL '
                                        + 'SELECT ''----------------------------------------------------------------------------------------------------'' '
                                        + 'UNION ALL '
                                        + 'SELECT ''-----| Execute sp_PivotExecute with parameters: columns and dimentions and main table name'' '
                                        + 'UNION ALL '
                                        + 'SELECT ''----------------------------------------------------------------------------------------------------'' '
                                        + 'UNION ALL '
                                        + 'SELECT ''EXEC [dbo].[sp_PivotExecute] @ColumnListWithActions, ' + '''''' + @TableName + '''''' + ';'''
                                        + 'UNION ALL '
                                        + 'SELECT ''----------------------------------------------------------------------------------------------------'' '                            


CREATE PROCEDURE [dbo].[sp_PivotExecute]
@ColumnListWithActions  ColumnActionList ReadOnly
,@TableName                     nvarchar(128)

--###| Step 1 - Select our user-defined-table-variable into temp table

IF OBJECT_ID('tempdb.dbo.#ColumnListWithActions', 'U') IS NOT NULL DROP TABLE #ColumnListWithActions; 
SELECT * INTO #ColumnListWithActions FROM @ColumnListWithActions;

--###| Step 2 - Preparing lists of column groups as strings:

DECLARE @ColumnName                     nvarchar(128)
DECLARE @Destiny                        nchar(1)

DECLARE @ListOfColumns_Stable           nvarchar(max)
DECLARE @ListOfColumns_Dimension    nvarchar(max)
DECLARE @ListOfColumns_Variable     nvarchar(max)
--###| Cursor for List of Stable Columns

DECLARE ColumnListStringCreator_S CURSOR FOR
SELECT      [ColumnName]
FROM        #ColumnListWithActions
WHERE       [Action] = 'S'
OPEN ColumnListStringCreator_S;
FETCH NEXT FROM ColumnListStringCreator_S
INTO @ColumnName

        SELECT @ListOfColumns_Stable = ISNULL(@ListOfColumns_Stable, '') + ' [' + @ColumnName + '] ,';
        FETCH NEXT FROM ColumnListStringCreator_S INTO @ColumnName

CLOSE ColumnListStringCreator_S;
DEALLOCATE ColumnListStringCreator_S;

--###| Cursor for List of Dimension Columns

DECLARE ColumnListStringCreator_D CURSOR FOR
SELECT      [ColumnName]
FROM        #ColumnListWithActions
WHERE       [Action] = 'D'
OPEN ColumnListStringCreator_D;
FETCH NEXT FROM ColumnListStringCreator_D
INTO @ColumnName

        SELECT @ListOfColumns_Dimension = ISNULL(@ListOfColumns_Dimension, '') + ' [' + @ColumnName + '] ,';
        FETCH NEXT FROM ColumnListStringCreator_D INTO @ColumnName

CLOSE ColumnListStringCreator_D;
DEALLOCATE ColumnListStringCreator_D;

--###| Cursor for List of Variable Columns

DECLARE ColumnListStringCreator_V CURSOR FOR
SELECT      [ColumnName]
FROM        #ColumnListWithActions
WHERE       [Action] = 'V'
OPEN ColumnListStringCreator_V;
FETCH NEXT FROM ColumnListStringCreator_V
INTO @ColumnName

        SELECT @ListOfColumns_Variable = ISNULL(@ListOfColumns_Variable, '') + ' [' + @ColumnName + '] ,';
        FETCH NEXT FROM ColumnListStringCreator_V INTO @ColumnName

CLOSE ColumnListStringCreator_V;
DEALLOCATE ColumnListStringCreator_V;

SELECT @ListOfColumns_Variable      = LEFT(@ListOfColumns_Variable, LEN(@ListOfColumns_Variable) - 1);
SELECT @ListOfColumns_Dimension = LEFT(@ListOfColumns_Dimension, LEN(@ListOfColumns_Dimension) - 1);
SELECT @ListOfColumns_Stable            = LEFT(@ListOfColumns_Stable, LEN(@ListOfColumns_Stable) - 1);

--###| Step 3 - Preparing table with all possible connections between Dimension columns excluding NULLs
DECLARE @DIM_TAB TABLE ([DIM_ID] smallint, [ColumnName] nvarchar(128))
SELECT [DIM_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName] FROM #ColumnListWithActions WHERE [Action] = 'D';

DECLARE @DIM_ID smallint;
SELECT      @DIM_ID = 1;

DECLARE @SQL_Dimentions nvarchar(max);

IF OBJECT_ID('tempdb.dbo.##ALL_Dimentions', 'U') IS NOT NULL DROP TABLE ##ALL_Dimentions; 

SELECT @SQL_Dimentions      = 'SELECT [xxx_ID_xxx] = ROW_NUMBER() OVER (ORDER BY ' + @ListOfColumns_Dimension + '), ' + @ListOfColumns_Dimension
                                            + ' INTO ##ALL_Dimentions '
                                            + ' FROM (SELECT DISTINCT' + @ListOfColumns_Dimension + ' FROM  ' + @TableName
                                            + ' WHERE ' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @DIM_ID) + ' IS NOT NULL ';
                                            SELECT @DIM_ID = @DIM_ID + 1;
            SELECT @SQL_Dimentions = @SQL_Dimentions + 'AND ' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @DIM_ID) +  ' IS NOT NULL ';
            SELECT @DIM_ID = @DIM_ID + 1;

SELECT @SQL_Dimentions   = @SQL_Dimentions + ' )x';


--###| Step 4 - Preparing table with all possible connections between Stable columns excluding NULLs
DECLARE @StabPos_TAB TABLE ([StabPos_ID] smallint, [ColumnName] nvarchar(128))
SELECT [StabPos_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName] FROM #ColumnListWithActions WHERE [Action] = 'S';

DECLARE @StabPos_ID smallint;
SELECT      @StabPos_ID = 1;

DECLARE @SQL_MainStableColumnTable nvarchar(max);

IF OBJECT_ID('tempdb.dbo.##ALL_StableColumns', 'U') IS NOT NULL DROP TABLE ##ALL_StableColumns; 

SELECT @SQL_MainStableColumnTable       = 'SELECT xxx_ID_xxx = ROW_NUMBER() OVER (ORDER BY ' + @ListOfColumns_Stable + '), ' + @ListOfColumns_Stable
                                            + ' INTO ##ALL_StableColumns '
                                            + ' FROM (SELECT DISTINCT' + @ListOfColumns_Stable + ' FROM  ' + @TableName
                                            + ' WHERE ' + (SELECT [ColumnName] FROM @StabPos_TAB WHERE [StabPos_ID] = @StabPos_ID) + ' IS NOT NULL ';
                                            SELECT @StabPos_ID = @StabPos_ID + 1;
            WHILE @StabPos_ID <= (SELECT MAX([StabPos_ID]) FROM @StabPos_TAB)
            SELECT @SQL_MainStableColumnTable = @SQL_MainStableColumnTable + 'AND ' + (SELECT [ColumnName] FROM @StabPos_TAB WHERE [StabPos_ID] = @StabPos_ID) +  ' IS NOT NULL ';
            SELECT @StabPos_ID = @StabPos_ID + 1;

SELECT @SQL_MainStableColumnTable    = @SQL_MainStableColumnTable + ' )x';


--###| Step 5 - Preparing table with all options ID


DECLARE @i smallint

IF OBJECT_ID('tempdb.dbo.##FinalTab', 'U') IS NOT NULL DROP TABLE ##FinalTab; 

SELECT @FULL_SQL_1 = 'SELECT t.*, dim.[xxx_ID_xxx] '
                                    + ' INTO ##FinalTab '
                                    +   'FROM ' + @TableName + ' t '
                                    +   'JOIN ##ALL_Dimentions dim '
                                    +   'ON t.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = 1) + ' = dim.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = 1);
                                SELECT @i = 2                               
                                WHILE @i <= (SELECT MAX([DIM_ID]) FROM @DIM_TAB)
                                    SELECT @FULL_SQL_1 = @FULL_SQL_1 + ' AND t.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @i) + ' = dim.' + (SELECT [ColumnName] FROM @DIM_TAB WHERE [DIM_ID] = @i)
                                    SELECT @i = @i +1

--###| Step 6 - Selecting final data
DECLARE @STAB_TAB TABLE ([STAB_ID] smallint, [ColumnName] nvarchar(128))
SELECT [STAB_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName]
FROM #ColumnListWithActions WHERE [Action] = 'S';

DECLARE @VAR_TAB TABLE ([VAR_ID] smallint, [ColumnName] nvarchar(128))
SELECT [VAR_ID] = ROW_NUMBER() OVER(ORDER BY [ColumnName]), [ColumnName]
FROM #ColumnListWithActions WHERE [Action] = 'V';

DECLARE @y smallint;
DECLARE @x smallint;
DECLARE @z smallint;

DECLARE @FinalCode nvarchar(max)

SELECT @FinalCode = ' SELECT ID1.*'
                                        SELECT @y = 1
                                        WHILE @y <= (SELECT MAX([xxx_ID_xxx]) FROM ##FinalTab)
                                                SELECT @z = 1
                                                WHILE @z <= (SELECT MAX([VAR_ID]) FROM @VAR_TAB)
                                                        SELECT @FinalCode = @FinalCode +    ', [ID' + CAST((@y) as varchar(10)) + '.' + (SELECT [ColumnName] FROM @VAR_TAB WHERE [VAR_ID] = @z) + '] =  ID' + CAST((@y + 1) as varchar(10)) + '.' + (SELECT [ColumnName] FROM @VAR_TAB WHERE [VAR_ID] = @z)
                                                        SELECT @z = @z + 1
                                                    SELECT @y = @y + 1
        SELECT @FinalCode = @FinalCode + 
                                        ' FROM ( SELECT * FROM ##ALL_StableColumns)ID1';
                                        SELECT @y = 1
                                        WHILE @y <= (SELECT MAX([xxx_ID_xxx]) FROM ##FinalTab)
                                            SELECT @x = 1
                                            SELECT @FinalCode = @FinalCode 
                                                                                + ' LEFT JOIN (SELECT ' +  @ListOfColumns_Stable + ' , ' + @ListOfColumns_Variable 
                                                                                + ' FROM ##FinalTab WHERE [xxx_ID_xxx] = ' 
                                                                                + CAST(@y as varchar(10)) + ' )ID' + CAST((@y + 1) as varchar(10))  
                                                                                + ' ON 1 = 1' 
                                                                                WHILE @x <= (SELECT MAX([STAB_ID]) FROM @STAB_TAB)
                                                                                    SELECT @FinalCode = @FinalCode + ' AND ID1.' + (SELECT [ColumnName] FROM @STAB_TAB WHERE [STAB_ID] = @x) + ' = ID' + CAST((@y+1) as varchar(10)) + '.' + (SELECT [ColumnName] FROM @STAB_TAB WHERE [STAB_ID] = @x)
                                                                                    SELECT @x = @x +1
                                            SELECT @y = @y + 1

SELECT * FROM ##ALL_Dimentions;

From executing the first query (by passing source DB and table name) you will get a pre-created execution query for the second SP, all you have to do is define is the column from your source: + Stable + Value (will be used to concentrate values based on that) + Dim (column you want to use to pivot by)

Names and datatypes will be defined automatically!

I cant recommend it for any production environments but does the job for adhoc BI requests.

@Html.DropDownListFor how to set default value

Like this:

@Html.DropDownListFor(model => model.Status, new List<SelectListItem> 
       { new SelectListItem{Text="Active", Value="True"},
         new SelectListItem{Text="Deactive", Value="False"}},"Select One")

If you want Active to be selected by default then use Selected property of SelectListItem:

@Html.DropDownListFor(model => model.Status, new List<SelectListItem> 
           { new SelectListItem{Text="Active", Value="True",Selected=true},
             new SelectListItem{Text="Deactive", Value="False"}},"Select One")

If using SelectList, then you have to use this overload and specify SelectListItem Value property which you want to set selected:

@Html.DropDownListFor(model => model.title, 
                     new SelectList(new List<SelectListItem>
      new SelectListItem { Text = "Active" , Value = "True"},
      new SelectListItem { Text = "InActive", Value = "False" }
    "Value", // property to be set as Value of dropdown item
    "Text",  // property to be used as text of dropdown item
    "True"), // value that should be set selected of dropdown
     new { @class = "form-control" })

What's the easiest way to escape HTML in Python?

For legacy code in Python 2.7, can do it via BeautifulSoup4:

>>> bs4.dammit import EntitySubstitution
>>> esub = EntitySubstitution()
>>> esub.substitute_html("r&d")

How to fit a smooth curve to my data in R?

LOESS is a very good approach, as Dirk said.

Another option is using Bezier splines, which may in some cases work better than LOESS if you don't have many data points.

Here you'll find an example:

# x, y: the x and y coordinates of the hull points
# n: the number of points in the curve.
bezierCurve <- function(x, y, n=10)
    outx <- NULL
    outy <- NULL

    i <- 1
    for (t in seq(0, 1, length.out=n))
        b <- bez(x, y, t)
        outx[i] <- b$x
        outy[i] <- b$y

        i <- i+1

    return (list(x=outx, y=outy))

bez <- function(x, y, t)
    outx <- 0
    outy <- 0
    n <- length(x)-1
    for (i in 0:n)
        outx <- outx + choose(n, i)*((1-t)^(n-i))*t^i*x[i+1]
        outy <- outy + choose(n, i)*((1-t)^(n-i))*t^i*y[i+1]

    return (list(x=outx, y=outy))

# Example usage
x <- c(4,6,4,5,6,7)
y <- 1:6
plot(x, y, "o", pch=20)
points(bezierCurve(x,y,20), type="l", col="red")

What Does This Mean in PHP -> or =>

The double arrow operator, =>, is used as an access mechanism for arrays. This means that what is on the left side of it will have a corresponding value of what is on the right side of it in array context. This can be used to set values of any acceptable type into a corresponding index of an array. The index can be associative (string based) or numeric.

$myArray = array(
    0 => 'Big',
    1 => 'Small',
    2 => 'Up',
    3 => 'Down'

The object operator, ->, is used in object scope to access methods and properties of an object. It’s meaning is to say that what is on the right of the operator is a member of the object instantiated into the variable on the left side of the operator. Instantiated is the key term here.

// Create a new instance of MyObject into $obj
$obj = new MyObject();
// Set a property in the $obj object called thisProperty
$obj->thisProperty = 'Fred';
// Call a method of the $obj object named getProperty

Catching multiple exception types in one catch block

A great way is to use set_exception_handler.

Warning!!! with PHP 7, you might get a white screen of death for fatal errors. For example, if you call a method on a non-object you would normally get Fatal error: Call to a member function your_method() on null and you would expect to see this if error reporting is on.

The above error will NOT be caught with catch(Exception $e). The above error will NOT trigger any custom error handler set by set_error_handler.

You must use catch(Error $e){ } to catch errors in PHP7. . This could help:

class ErrorHandler{
    public static function excep_handler($e)

Bash: Echoing a echo command with a variable in bash

You just need to use single quotes:

$ echo "$TEST"
$ echo '$TEST'

Inside single quotes special characters are not special any more, they are just normal characters.

How to sort a List<Object> alphabetically using Object name field

If your objects has some common ancestor [let it be T] you should use List<T> instead of List<Object>, and implement a Comparator for this T, using the name field.

If you don't have a common ancestor, you can implement a Comperator, and use reflection to extract the name, Note that it is unsafe, unsuggested, and suffers from bad performance to use reflection, but it allows you to access a field name without knowing anything about the actual type of the object [besides the fact that it has a field with the relevant name]

In both cases, you should use Collections.sort() to sort.

Class JavaLaunchHelper is implemented in two places

Since “this message is harmless”(see the @CrazyCoder's answer), a simple and safe workaround is that you can fold this buzzing message in console by IntelliJ IDEA settings:

  1. ?Preferences?- ?Editor?-?General?-?Console?- ?Fold console lines that contain?
    Of course, you can use ?Find Action...?(cmd+shift+A on mac) and type Fold console lines that contain so as to navigate more effectively.
  2. add Class JavaLaunchHelper is implemented in both


On my computer, It turns out: (LGTM :b )


And you can unfold the message to check it again:



As of October 2017, this issue is now resolved in jdk1.9/jdk1.8.152/jdk1.7.161
for more info, see the @muttonUp's answer)

Change border-bottom color using jquery?

$("selector").css("border-bottom-color", "#fff");
  1. construct your jQuery object which provides callable methods first. In this case, say you got an #mydiv, then $("#mydiv")
  2. call the .css() method provided by jQuery to modify specified object's css property values.

Best way to define private methods for a class in Objective-C

There is a benefit of private methods absence. You can move the logic that you intended to hide to the separate class and use it as delegate. In this case you can mark delegate object as private and it will not be visible from outside. Moving logic to the separate class (maybe several) makes better design of your project. Cause your classes become simpler and your methods are grouped in classes with proper names.

How to POST request using RestSharp

As of 2017 I post to a rest service and getting the results from it like that:

        var loginModel = new LoginModel();
        loginModel.DatabaseName = "TestDB";
        loginModel.UserGroupCode = "G1";
        loginModel.UserName = "test1";
        loginModel.Password = "123";

        var client = new RestClient(BaseUrl);

        var request = new RestRequest("/Connect?", Method.POST);
        request.RequestFormat = DataFormat.Json;

        var response = client.Execute(request);

        var obj = JObject.Parse(response.Content);

        LoginResult result = new LoginResult
            Status = obj["Status"].ToString(),
            Authority = response.ResponseUri.Authority,
            SessionID = obj["SessionID"].ToString()

Insert line break inside placeholder attribute of a textarea?

Try this:


Column "invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause"

Put in other words, this error is telling you that SQL Server does not know which B to select from the group.

Either you want to select one specific value (e.g. the MIN, SUM, or AVG) in which case you would use the appropriate aggregate function, or you want to select every value as a new row (i.e. including B in the GROUP BY field list).

Consider the following data:

ID  A   B
1   1  13
1   1  79
1   2  13
1   2  13
1   2  42

The query


would return:

A  T1
1  2
2  3

which is all well and good.

However consider the following (illegal) query, which would produce this error:


And its returned data set illustrating the problem:

A  T1  B
1  2   13? 79? Both 13 and 79 as separate rows? (13+79=92)? ...?
2  3   13? 42? ...?

However, the following two queries make this clear, and will not cause the error:

  1. Using an aggregate

    FROM T2

    would return:

    A  T1  B
    1  2   92
    2  3   68
  2. Adding the column to the GROUP BY list

    FROM T2

    would return:

    A  T1  B
    1  1   13
    1  1   79
    2  2   13
    2  1   42

How to position a div in bottom right corner of a browser?

Try this:

    position: absolute;
    top: 100%;
    right: 0%;