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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; ...

1. Passing integer data: SenderActivity Intent myIntent = new Intent(SenderActivity.this, ReceiverActivity.class); myIntent.putExtra("intVariableName", intValue); startActivity(myIntent); ReceiverActivity Intent mIntent = getIntent(); int intValue = mIntent.getIntExtra("intVa...

To change UI content in runtime, you can use Binding. When binded property is changed from the code, it will be displayed to the UI. <TextBlock Text="{Binding Title}"/> To notify UI about changes, property must raise PropertyChanged event from INotifyPropertyChanged interface or ...

In addition to the concept of column units, Bootstrap has different breakpoints or grid sizes known as tiers. The Bootstrap 3 grid has four (4) tiers to accomodate different screen (or viewport) widths. The Bootstrap 3 tiers are xs, sm, md, and lg. Bootstrap’s grid columns are identified by differen...

using System.Threading; class MainClass { static void Main() { var thread = new Thread(Secondary); thread.Start("SecondThread"); } static void Secondary(object threadName) { System.Console.WriteLine("Hello World from thread: " + thread...

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...

Given a file using ; as a column delimiter. We compute the mean of the values in the second column with the following program, the provided input is the list of grades of a student group: awk -F';' '{ sum += $2 } END { print(sum / NR) }' <<EOF Alice;2 Victor;1 Barbara;1 Casper;4 Deborah;...

This command starts up a development server, or dev server, for your Dart web app. The dev server is an HTTP server on localhost that serves up your web app’s assets. Start the dev server from the directory that contains your web app’s pubspec.yaml file: $ cd ~/dart/helloworld $ pub serve Servin...

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."

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...

If you want PHP to display runtime errors on the page, you have to enable display_errors, either in the php.ini or using the ini_set function. You can choose which errors to display, with the error_reporting (or in the ini) function, which accepts E_* constants, combined using bitwise operators. P...

#include <stdio.h> int main(void) { /* define a small bit-field that can hold values from 0 .. 7 */ struct { unsigned int uint3: 3; } small; /* extract the right 3 bits from a value */ unsigned int value = 255 - 2; /* Binary 11111101 */ small.u...

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();

When inheriting from base Controller class provided by the framework, you can use the convenience method ViewComponent() to return a view component from the action: public IActionResult GetMyComponent() { return ViewComponent("Login", new { param1 = "foo", param2 = 42 }); ...

In Ansible, a playbook is is a YAML file containing the definition of how a server should look. In a playbook you define what actions Ansible should take to get the server in the state you want. Only what you define gets done. This is a basic Ansible playbook that installs git on every host belongi...