Tutorial by Examples: u

Some procedures have optional arguments. Optional arguments always come after required arguments, but the procedure can be called without them. For example, if the function, ProcedureName were to have two required arguments (argument1, argument2), and one optional argument, optArgument3, it could b...

library(gpuR) # gpuMatrix objects X <- gpuMatrix(rnorm(100), 10, 10) Y <- gpuMatrix(rnorm(100), 10, 10) # transfer data to GPU when operation called # automatically copied back to CPU Z <- X %*% Y

library(gpuR) # vclMatrix objects X <- vclMatrix(rnorm(100), 10, 10) Y <- vclMatrix(rnorm(100), 10, 10) # data always on GPU # no data transfer Z <- X %*% Y

Download the Apache Felix Framework Distribution and extract it into a directory: $ tar xf org.apache.felix.main.distribution-5.4.0.tar.gz $ cd felix-framework-5.4.0 And then start the framework with the following command: $ java -jar bin/felix.jar ____________________________ Welcome to...

The ProcessBuilder class makes it easy to send a command through the command line. All it requires is a List of Strings that make up the commands to be entered. You simply call the start() method on your ProcessBuilder instance to execute the command. If you have a program called Add.exe which take...

Launching external processes from Java using the raw java.lang.ProcessBuilder API directly can be a little cumbersome. The Apache Commons Exec library makes it a little easier. The ch.vorburger.exec library further extends upon Commons Exec to make it truly convenient: ManagedProcess proc = new ...

This proxy simply appends the string " went through proxy" to every string property set on the target object. let object = {}; let handler = { set(target, prop, value){ // Note that ES6 object syntax is used if('string' === typeof value){ target[prop] = valu...

Laravel's events allows to implement the Observer pattern. This can be used to send a welcome email to a user whenever they register on your application. New events and listeners can be generated using the artisan command line utility after registering the event and their particular listener in App...

A transaction acts on a single database connection. If you have multiple class-specific databases, the transaction will not protect interaction among them. One workaround is to begin a transaction on each class whose models you alter: Student.transaction do Course.transaction do course.enro...

Both #save and #destroy come wrapped in a transaction that ensures that whatever you do in validations or callbacks will happen under its protected cover. So you can use validations to check for values that the transaction depends on or you can raise exceptions in the callbacks to rollback, includin...

Create a file named launch-server.yaml, that will be our playbook. The first part of the playbook is a list of hosts that your playbook will run on, we only have one, localhost. - hosts: localhost Then we need to define a list of tasks to perform in this playbook. We will only have one that lau...

Run the Ansible playbook: $ ansible-playbook launch-server.yaml You should see output like PLAY [localhost] *************************************************************** TASK [setup] ******************************************************************* ok: [localhost] TASK [launch an U...

Using NuGet Install-Package Cirrious.FluentLayout An expanded example based on the starter example at the GitHub Page, a simple first name, last name labels and fields all stacked one on top of the other: public override void ViewDidLoad() { //create our labels and fields var firstNa...

Built-in functionals: lapply(), sapply(), and mapply() R comes with built-in functionals, of which perhaps the most well-known are the apply family of functions. Here is a description of some of the most common apply functions: lapply() = takes a list as an argument and applies the specified ...

User-defined functionals Users can create their own functionals to varying degrees of complexity. The following examples are from Functionals by Hadley Wickham: randomise <- function(f) f(runif(1e3)) lapply2 <- function(x, f, ...) { out <- vector("list", length(x...

Using SVG stroke makes it easier to create a Vector drawable with unified stroke length, as per Material Design guidelines: Consistent stroke weights are key to unifying the overall system icon family. Maintain a 2dp width for all stroke instances, including curves, angles, and both interior and ...

The following will prompt a user for input, and then store that input as a string (text) in a variable. The variable is then used to give a message to the user. #!/usr/bin/env bash echo "Who are you?" read name echo "Hello, $name." The command read here reads one line of ...

In Sinatra, routing is how your app responds to requests, by the path of the request (e.g. /welcome) and by the HTTP verb used (e.g. GET or POST). The way a request is written is as follows: <http-verb> <path> do <code block to execute when this route is requested> end He...

To print a test field (TestField) from a test feature class (TestFC) in a test file geodatabase (Test.gdb) located in a temporary folder (C:\Temp): with arcpy.da.SearchCursor(r"C:\Temp\Test.gdb\TestFC",["TestField"]) as cursor: for row in cursor: print row[0]

long fib(long n) { return n < 2 ? n : fib(n - 1) + fib(n - 2); } struct FibStruct(int n) { // Remarks: n is a template ubyte[fib(n)] data; } void main() { import std.stdio : writeln; enum f10 = fib(10); // execute the function at compile-time pragma(msg, f10); /...