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The key in vectorizing R code, is to reduce or eliminate "by row operations" or method dispatching of R functions. That means that when approaching a problem that at first glance requires "by row operations", such as calculating the means of each row, one needs to ask themselves...

C99 These functions returns the floating-point remainder of the division of x/y. The returned value has the same sign as x. Single Precision: #include <math.h> /* for fmodf() */ #include <stdio.h> /* for printf() */ int main(void) { float x = 10.0; float y = 5.1; ...

function transform(fn, arr) { let result = []; for (let el of arr) { result.push(fn(el)); // We push the result of the transformed item to result } return result; } console.log(transform(x => x * 2, [1,2,3,4])); // [2, 4, 6, 8] As you can see, our transform fun...

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If you're doing multiple long calculations, you can run them at the same time on different threads on your computer. To do this, we make a new Thread and have it point to a different method. using System.Threading; class MainClass { static void Main() { var thread = new Thread(Seco...

Environment.ProcessorCount Gets the number of logical processors on the current machine. The CLR will then schedule each thread to a logical processor, this theoretically could mean each thread on a different logical processor, all threads on a single logical processor or some other combination...

Using a doc comment instead of a regular comment enables dartdoc to find it and generate documentation for it. /// The number of characters in this chunk when unsplit. int get length => ... You are allowed to use most markdown formatting in your doc comments and dartdoc will process it accor...

If you want to use only part of a library, you can selectively import the library. For example: // Import only foo and bar. import 'package:lib1/lib1.dart' show foo, bar; // Import all names EXCEPT foo. import 'package:lib2/lib2.dart' hide foo;

class CustomException implements Exception { String cause; CustomException(this.cause); } void main() { try { throwException(); } on CustomException { print("custom exception is been obtained"); } } throwException() { throw new CustomException('This is m...

iex(1)> name = "John" "John" iex(2)> greeting = "Hello, #{name}" "Hello, John" iex(3)> num = 15 15 iex(4)> results = "#{num} item(s) found." "15 item(s) found."

It is a good practice to provide expression string arguments as braced strings. The heading "Double Substitution" outlines important reasons behind the same. The expr command evaluates an operator-based expression string to calculate a value. This string is constructed from the arguments ...

When the view controller is presented within a tab bar controller, you can access the tab bar controller like this: Swift let tabBarController = viewController.tabBarController Objective-C UITabBarController *tabBarController = self.tabBarController; When the view controller is part on an n...

JavaScript has native conversion from Number to it's String representation for any base from 2 to 36. The most common representation after decimal (base 10) is hexadecimal (base 16), but the contents of this section work for all bases in the range. In order to convert a Number from decimal (base...

You can use gradle to have BuildConfig constants and res values on a per flavor basis. Just add the value to the flavor you want to support. android { defaultConfig { resValue "string", "app_name", "Full App" buildConfigField "boolean",...

Matlab supports synchronous and asynchronous communication with a serial port. It is important to chose the right communication mode. The choice will depend on: how the instrument you are communicating with behave. what other functions your main program (or GUI) will have to do aside from managi...

You can convert a numeric string to various Java numeric types as follows: String to int: String number = "12"; int num = Integer.parseInt(number); String to float: String number = "12.0"; float num = Float.parseFloat(number); String to double: String double = "1...

namespace App\Controller; class PostsController extends AppController { public function initialize(){ parent::initialize(); // code that you want to run before every action } public function view($id) { //Your code here } }

The beforeFilter() method executes before any other method executes in the controller. First use the Event namespace before defining the class in your controller file. use Cake\Event\Event; In your controller, add the beforeFilter() method as shown below. public function beforeFilter(Event $ev...

By default CakePHP loads the related model in the controller. In order to load another model in the controller, use the loadModel() method: $this->loadModel('Articles'); or load on the fly $table = TableRegistry::get('Articles'); $table->find();

Dim fso As New Scripting.FileSystemObject Debug.Print fso.GetBaseName("MyFile.something.txt") Prints MyFile.something Note that the GetBaseName() method already handles multiple periods in a file name.