Tutorial by Examples: l

Instantiate a XMLWriter object: $xml = new XMLWriter(); Next open the file to which you want to write. For example, to write to /var/www/example.com/xml/output.xml, use: $xml->openUri('file:///var/www/example.com/xml/output.xml'); To start the document (create the XML open tag): $xml-&gt...

Knockout is available on most JavaScript platforms, or as a standalone script. Include as a script You can download the script from it's download page, then include it in your page with a standard script tag <script type='text/javascript' src='knockout-3.4.0.js'></script> Using a C...

Sometimes you may want to start a new activity while removing previous activities from the back stack, so the back button doesn't take you back to them. One example of this might be starting an app on the Login activity, taking you through to the Main activity of your application, but on logging out...

The built-in mtcars data frame contains information about 32 cars, including their weight, fuel efficiency (in miles-per-gallon), speed, etc. (To find out more about the dataset, use help(mtcars)). If we are interested in the relationship between fuel efficiency (mpg) and weight (wt) we may start p...

apply is used to evaluate a function (maybe an anonymous one) over the margins of an array or matrix. Let's use the iris dataset to illustrate this idea. The iris dataset has measurements of 150 flowers from 3 species. Let's see how this dataset is structured: > head(iris) Sepal.Length Sep...

A table can be replicated as follows: CREATE TABLE ClonedPersons LIKE Persons; The new table will have exactly the same structure as the original table, including indexes and column attributes. As well as manually creating a table, it is also possible to create table by selecting data from anot...

When a method need to accept an "extensible" set of enum values, the programmer can apply polymorphism like on a normal class by creating an interface which will be used anywere where the enums shall be used: public interface ExtensibleEnum { String name(); } This way, any enum t...

Method 1: Below query will be applicable for SQL Server 2000+ version (Contains 12 columns) SELECT * FROM dbo.sysdatabases Method 2: Below query extract information about databases with more informations (ex: State, Isolation, recovery model etc.) Note: This is a catalog view and will be availa...

First we need to install composer. Steps to install composer Install Composer. curl -sS https://getcomposer.org/installer | php Now change directory: sudo mv composer.phar /usr/local/bin/composer Check composer working composer Now Composer installed. There two ways to install Yii2 adv...

Adding elements: [1, 2, 3] << 4 # => [1, 2, 3, 4] [1, 2, 3].push(4) # => [1, 2, 3, 4] [1, 2, 3].unshift(4) # => [4, 1, 2, 3] [1, 2, 3] << [4, 5] # => [1, 2, 3, [4, 5]] Removing elements: array = [1, 2, 3, 4] array.pop # => 4 array # => [1, 2, 3] ...

A while loop executes the block while the given condition is met: i = 0 while i < 5 puts "Iteration ##{i}" i +=1 end An until loop executes the block while the conditional is false: i = 0 until i == 5 puts "Iteration ##{i}" i +=1 end

Prerequisites and Requirements for Magento Community Edition 1.9 Hosting Apache 2.x ( with mod_rewrite ) or Nginx 1.7.x Due to the demands of processing Magento operations, it is recommended that you install Magento on a server with at least 2 GB of RAM. This will ensure that all of the s...

One of the most common misconceptions about OpenGL is, that it were a library that could be installed from 3rd party sources. This misconception leads to many questions in the form "how to I install OpenGL" or "where to download the OpenGL SDK". This is not how OpenGL finds the ...

Windows If you have Visual Studio (any version including express and community) installed, F# should already be included. Just choose F# as the language when you create a new project. Or see http://fsharp.org/use/windows/ for more options. OS X Xamarin Studio supports F#. Alternately, you could u...

All is used to check, if all elements of a collection match a condition or not. see also: .Any 1. Empty parameter All: is not allowed to be used with empty parameter. 2. Lambda expression as parameter All: Returns true if all elements of collection satisfies the lambda expression and false othe...

Downloading: Download Bootstrap directly or clone, etc. from the GitHub repository Download your customized version of Bootstrap from official docs Install with bower: bower install bootstrap Install with npm: npm install bootstrap Install with composer: composer require twbs/bootstrap The...

Even just reading the value of a pointer that was freed (i.e. without trying to dereference the pointer) is undefined behavior(UB), e.g. char *p = malloc(5); free(p); if (p == NULL) /* NOTE: even without dereferencing, this may have UB */ { } Quoting ISO/IEC 9899:2011, section 6.2.4 §2: ...

Stability in sorting means whether a sort algorithm maintains the relative order of the equals keys of the original input in the result output. So a sorting algorithm is said to be stable if two objects with equal keys appear in the same order in sorted output as they appear in the input unsorted a...

If a selection on multiple arguments for a type generic expression is wanted, and all types in question are arithmetic types, an easy way to avoid nested _Generic expressions is to use addition of the parameters in the controlling expression: int max_int(int, int); unsigned max_unsigned(unsigned, ...

Note: Before deciding which Stream to use please have a look at ParallelStream vs Sequential Stream behavior. When you want to perform Stream operations concurrently, you could use either of these ways. List<String> data = Arrays.asList("One", "Two", "Three", &q...