Tutorial by Examples: g

An image can be created using image* functions, where * is the file format. They have this syntax in common: bool image___(resource $im [, mixed $to [ other parameters]] ) Saving to a file If you want to save the image to a file, you can pass the filename, or an opened file stream, as $to. If ...

<ItemGroup> <DataToCopy Include="*.cs;*.aspx" /> </ItemGroup> <Copy SourceFiles="@(DataToCopy)" DestinationFolder="SourceCopiedFolder" />

A Haskell's Functor allows one to map any type a (an object of Hask) to a type F a and also map a function a -> b (a morphism of Hask) to a function with type F a -> F b. This corresponds to a Category Theory definition in a sense that functor preserves basic category structure. A monoidal ca...

It may be helpful to include additional information with an exception, e.g. for logging purposes or to allow conditional handling when the exception is caught: class CustomError < StandardError attr_reader :safe_to_retry def initialize(safe_to_retry = false, message = 'Something went wro...

If you want to set some alias name to installed node version, do: nvm alias <name> <version> Similary to unalias, do: nvm unalias <name> A proper usecase would be, if you want to set some other version than stable version as default alias. default aliased versions are loade...

In this example we create a new list element with the text "new text", and select the first unordered list, and its first list element. let newElement = document.createElement("li"); newElement.innerHTML = "new text"; let parentElement = document.querySelector(&quo...

In this example we create a new list element with the text "new text", and select the first unordered list, and its first list element. let newElement = document.createElement("li"); newElement.innerHTML = "new text"; let parentElement = document.querySelector(&quo...

An element can be removed by calling remove() on it. Alternatively, one can call removeChild() on its parent. removeChild() has better browser support than remove(). element.remove(); element, and all its childnodes, are removed from the DOM. parentElement.removeChild(element); element...

There are several ways of getting the data that you will bind to the DOM elements. The simpler one is having your data in your script as an array... var data = [ ... ]; But D3.js allows us to load data from an external file. In this example, we will see how to properly load and deal with data fr...

You can create ACL by using Phalcon\Acl\Adapter\Memory class: $acl = new Phalcon\Acl\Adapter\Memory(); By default phalcon allows action to resource which has not been defined, to change this you can use: $acl->setDefaultAction(Phalcon\Acl::DENY); Roles can be added in two ways - using Pha...

You can allow role to access some action on resource by: $acl->allow('Administrator', 'products', 'create'); You can deny role to access some action on resource by: $acl->deny('Customer', 'categories', 'create'); You can check if role is allowed to some action on resource by using: $a...

Modifying the strings returned by the standard functions getenv(), strerror() and setlocale() is undefined. So, implementations may use static storage for these strings. The getenv() function, C11, §7.22.4.7, 4, says: The getenv function returns a pointer to a string associated with the matched...

var path = "/test_javascript_upload.txt"; var content = "data to upload"; var accessToken = "<ACCESS_TOKEN>"; var uploadUrl = "https://content.dropboxapi.com/2/files/upload" var result; var xhr = new XMLHttpRequest(); xhr.onreadystatechange = fun...

The regexp command is used to match a regular expression against a string. # This is a very simplistic e-mail matcher. # e-mail addresses are extremely complicated to match properly. # there is no guarantee that this regex will properly match e-mail addresses. set mydata "send mail to john....

If you have a greedy match as the first quantifier, the whole RE will be greedy, If you have non-greedy match as the first quantifier, the whole RE will be non-greedy. set mydata { Device widget1: port: 156 alias: input2 Device widget2: alias: input1 Device widget3: port: 238 alias...

\m : Beginning of a word. \M : End of a word. \y : Word boundary. \Y : a point that is not a word boundary. \Z : matches end of data. Documentation: re_syntax

# example data DT = data.table(id = c(1,2,2,3,3,3))[, v := LETTERS[.I]][] To deal with "duplicates," combine counting rows in a group and subsetting rows by group. Keep one row per group Aka "drop duplicates" aka "deduplicate" aka "uniquify." unique(DT,...

There are many examples where backticks are used inside a query but for many it's still unclear when or where to use backticks ``. Backticks are mainly used to prevent an error called "MySQL reserved word". When making a table in PHPmyAdmin you are sometimes faced with a warning or alert ...

Literals in RDF may be language tagged strings. These literals have a text part as well as a language tag. For instance, the literal "color"@en has the text part "color" and the language tag "en". In a SPARQL query, use the lang function to get the language of a lite...

The SPARQL function langMatches can be used to compare the language tags of RDF literals in SPARQL queries. The simple equality operator, =, can be used to compare exact string matches, but will not correctly consider regional variants. For instance, the four possible values of ?str in: values ...