Tutorial by Examples: ar

Most advanced user interfaces require the user to be able to pass information between the various functions which make up a user interface. MATLAB has a number of different methods to do so. guidata MATLAB's own GUI Development Environment (GUIDE) prefers to use a struct named handles to pass da...

Floating-point numbers cannot represent all real numbers. This is known as floating point inaccuracy. There are infinitely many floating points numbers and they can be infinitely long (e.g. π), thus being able to represent them perfectly would require infinitely amount of memory. Seeing this was a ...

To add/subtract time, use POSIXct, since it stores times in seconds ## adding/subtracting times - 60 seconds as.POSIXct("2016-01-01") + 60 # [1] "2016-01-01 00:01:00 AEDT" ## adding 3 hours, 14 minutes, 15 seconds as.POSIXct("2016-01-01") + ( (3 * 60 * 60) + (14 ...

for comprehensions in Scala are just syntactic sugar. These comprehensions are implemented using the withFilter, foreach, flatMap and map methods of their subject types. For this reason, only types that have these methods defined can be utilized in a for comprehension. A for comprehension of the fo...

The r method implicitly provided via scala.collection.immutable.StringOps produces an instance of scala.util.matching.Regex from the subject string. Scala's triple-quoted string syntax is useful here, as you do not have to escape backslashes as you would in Java: val r0: Regex = """(...

Comparing string in a case insensitive way seems like something that's trivial, but it's not. This section only considers unicode strings (the default in Python 3). Note that Python 2 may have subtle weaknesses relative to Python 3 - the later's unicode handling is much more complete. The first thi...

redis-server

The ANSI CL standard uses an extended EBNF syntax notation. The documentation duplicated on Stackoverflow should use the same syntax notation to reduce confusion. Example: specialized-lambda-list::= ({var | (var parameter-specializer-name)}* [&optional {var | (var [initform [supp...

Given this object: var obj = { a: "hello", b: "this is", c: "javascript!", }; You can convert its values to an array by doing: var array = Object.keys(obj) .map(function(key) { return obj[key]; }); console.log(array); // [&quot...

- initWithCalendarIdentifier: Initializes a newly-allocated NSCalendar object for the calendar specified by a given identifier. NSCalendar *calender = [[NSCalendar alloc]initWithCalendarIdentifier:@"gregorian"]; NSLog(@"%@",calender); - setFirstWeekday: Sets the index of the...

ob_start is especially handy when you have redirections on your page. For example, the following code won't work: Hello! <?php header("Location: somepage.php"); ?> The error that will be given is something like: headers already sent by <xxx> on line <xxx>. In or...

The HTML attribute contenteditable provides a simple way to turn a HTML element into a user-editable area <div contenteditable>You can <b>edit</b> me!</div> Native Rich-Text editing Using JavaScript and execCommandW3C you can additionally pass more editing features to th...

On CLiki, a Wiki for Common Lisp and free Common Lisp software, a list of Proposed ANSI Revisions and Clarifications is being maintained. Since the Common Lisp standard has not changed since 1994, users have found several problems with the specification document. These are documented on the CLiki p...

The split-sequence library provides a function split-sequence, which allows to split on elements of a sequence (split-sequence:split-sequence #\Space "John Doe II") ;; => ("John" "Doe" "II")

From the official documentation: If you want to get advanced, you can also open up the project file for a specific platform by opening the required XCode or Android Eclipse project in platforms/PLATFORM inside the root of your project. Then, you can build and test from inside the platform-specifi...

There are several good examples of using lambdas as a FunctionalInterface in simple scenarios. A fairly common use case that can be improved by lambdas is what is called the Execute-Around pattern. In this pattern, you have a set of standard setup/teardown code that is needed for multiple scenarios ...

When to use Virtually all WPF controls make heavy use of dependency properties. A dependency property allows for the use of many WPF features that are not possible with standard CLR properties alone, including but not limited to support for styles, animations, data binding, value inheritance, and c...

implode() combines all the array values but looses all the key info: $arr = ['a' => "AA", 'b' => "BB", 'c' => "CC"]; echo implode(" ", $arr); // AA BB CC Imploding keys can be done using array_keys() call: $arr = ['a' => "AA", 'b'...

Generic parameters can also be bound to more than one type using the T extends Type1 & Type2 & ... syntax. Let's say you want to create a class whose Generic type should implement both Flushable and Closeable, you can write class ExampleClass<T extends Flushable & Closeable> { }...

You can remove all the elements in a set using the .clear() method: mySet.clear();