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Assuming a workspace named workspace_name has been previously created in the home directory, a package named package_name can be created by executing the following command lines. $ cd ~/workspace_name/src/ $ catkin_create_pkg package_name rospy

The if statement is a conditional statement that allows a program to enter or not a specific section of code depending if the condition(s) of the statement are met or not. It can be found in mostly all the existing programming languages. The if statement will usually take the following shape: if(s...

A statement is usually a test on a variable or the return value of a function. To test those values, we can use some relational operators: OperatorMeaningExample==Equal to1 == 1 is TRUE, 1 == 2 is FALSE!=Not equal to1 != 2 is TRUE, 1 != 1 is FALSE<Less than1 < 2 is TRUE, 2 < 1 is FALSE>...

It is possible to ask a program to execute a specific section of code only if an if statement is considered false. For this, we use the else key word. if(statement) { // Code to execute if the statement is true. } else { // Code to execute if the statement is false. } Both code se...

std::integer_sequence itself is about holding a sequence of integers which can be turned into a parameter pack. Its primary value is the possibility to create "factory" class templates creating these sequences: #include <iostream> #include <initializer_list> #include <uti...

The phpunit.xml file is the default configuration file for tests and is already setup for testing with PHPUnit. The default testing environment APP_ENV is defined as testing with array being the cache driver CACHE_DRIVER. With this setup, no data (session/cache) will be retained while testing. T...

Declaring the splat is useful for reusing sets of parameters multiple times or with slight variations: $splat = @{ Class = "Win32_SystemEnclosure" Property = "Manufacturer" ErrorAction = "Stop" } Get-WmiObject -ComputerName $env:COMPUTERNAME @splat Get...

2xx Success 200 OK - Standard response for successful HTTP requests. 201 Created - The request has been fulfilled, resulting in the creation of a new resource. 204 No Content - The server successfully processed the request and is not returning any content. 3xx Redirection 304 Not Modified...

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration]; AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration]; NSURL *URL = [NSURL URLWithString:@"http://example.com/upload"]; NSURLRequest *r...

NSMutableURLRequest *request = [[AFHTTPRequestSerializer serializer] multipartFormRequestWithMethod:@"POST" URLString:@"http://example.com/upload" parameters:nil constructingBodyWithBlock:^(id<AFMultipartFormData> formData) { [formData appendPartWithFileURL:[NSURL ...

HTTPS server with http location: server { listen 443; root /var/www/ location / { ... } location /http { rewrite ^ http://$host$request_uri? permanent; } } HTTP server redirects to HTTPS except one location: server { root /var/www/ locat...

CMAKE_MINIMUM_REQUIRED(VERSION 2.8.11) SET(PROJ_NAME "myproject") PROJECT(${PROJ_NAME}) # Configuration types SET(CMAKE_CONFIGURATION_TYPES "Debug;Release" CACHE STRING "Configs" FORCE) IF(DEFINED CMAKE_BUILD_TYPE AND CMAKE_VERSION VERSION_GREATER "2.8"...

Vibrate the device for 100ms: window.navigator.vibrate(100); or window.navigator.vibrate([100]);

An array of values describes periods of time in which the device is vibrating and not vibrating. window.navigator.vibrate([200, 100, 200]);

class User extends Model { public function setPasswordAttribute($password) { $this->attributes['password'] = bcrypt($password); } ... } Above code does "bcrypting" each time password property is set. $user = $users->first(); $user->password ...

Suppose we have a SharePoint list and it has four fields viz. Title, Full Name, Email, Mobile Number etc. Now if you want to apply custom validation in New/Edit Item form, you can easily do it with CSR code. The below mentioned can validate following conditions in forms: Blank values in fields ...

app\Exceptions\Handler.php public function render($request, Exception $exception) { if ($exception instanceof ModelNotFoundException) { abort(404); } return parent::render($request, $exception); } You can catch / handle any exception that is thrown in Laravel.

One example of machine learning algorithms is the Random Forest alogrithm (Breiman, L. (2001). Random Forests. Machine Learning 45(5), p. 5-32). This algorithm is implemented in R according to Breiman's original Fortran implementation in the randomForest package. Random Forest classifier objects ca...

Each log line is formatted as follows: timestamp source[dyno]: message Timestamp - The date and time recorded at the time the log line was produced by the dyno or component. The timestamp is in the format specified by RFC5424, and includes microsecond precision. Source - All of your app...

- name: Run script as foo user command: bash.sh become: true become_user: foo