Tutorial by Topics: es

When we don't know the value a variable takes, we say its value is missing, indicated by NA. Missing values are represented by the symbol NA (not available). Impossible values (e.g., as a result of sqrt(-1)) are represented by the symbol NaN (not a number).

Superglobals are built-in variables that are always available in all scopes. Several predefined variables in PHP are "superglobals", which means they are available in all scopes throughout a script. There is no need to do global $variable; to access them within functions or methods. ...

Note about XML syntax: As the record is made inside of XML file, you can not leave any tag unclosed as you could in a plain HTML, like: <link rel='stylesheet' href="..." >, Close the link tag instead, like: <link rel='stylesheet' href="..." /> Possible ...

coroutine.create(function) returns a coroutine (type(coroutine) == 'thread') containing the function. coroutine.resume(co, ...) resume, or start the coroutine. Any additional arguments given to resume are returned from the coroutine.yield() that previously paused the coroutine. If the corou...

It's easy to see types like a table in an SQL database, where the index is the SQL database. However, that is not a good way to approach types. All About Types In fact, types are literally just a metadata field added to each document by Elasticsearch: _type. The examples above created two type...

public Coroutine StartCoroutine(IEnumerator routine); public Coroutine StartCoroutine(string methodName, object value = null); public void StopCoroutine(string methodName); public void StopCoroutine(IEnumerator routine); public void StopAllCoroutines(); Performance considerations It...

Complete list of assertions. Examples: assertTrue(bool $condition[, string $messageIfFalse = '']); assertEquals(mixed $expected, mixed $actual[, string $messageIfNotEqual = '']); Unit tests are used for testing source code to see if it contains deals with inputs as we expect. Unit tests a...

Cross-origin resource sharing is designed to allow dynamic requests between domains, often using techniques such as AJAX. While the scripting does most of the work, the HTTP server must support the request using the correct headers.

Variable scope refers to the regions of code where a variable may be accessed. This is also referred to as visibility. In PHP scope blocks are defined by functions, classes, and a global scope available throughout an application.

This section provides an overview of what image-processing is, and why a developer might want to use it. It should also mention any large subjects within image-processing, and link out to the related topics. Since the Documentation for image-processing is new, you may need to create initial vers...

The assignment of string-literals in VBA is confined by the limitations of the IDE and the codepage of the current user's language settings. The examples above demonstrate the special-cases of escaped strings, special, non-printable strings and long string-literals. When assigning string-literals...

Variables are used for storing values. Let the value be of any type , we need to store it somewhere so that we can use it throughout the console/script. Variable names in PowerShell begin with a $, as in $Variable1, and values are assigned using =, like $Variable1 = "Value 1".PowerShell su...

VBA will implicitly convert some types to string as necessary and without any extra work on the part of the programmer, but VBA also provides a number of explicit string conversion functions, and you can also write your own. Three of the most frequently used functions are CStr, Format and StrConv...