Tutorial by Examples: d

int i; int n = 1000000; double area = 0; double h = 1.0 / n; #pragma omp parallel for shared(n, h) reduction(+:area) for (i = 1; i <= n; i++) { double x = h * (i - 0.5); area += (4.0 / (1.0 + x*x)); } pi = h * area; In this example, each threads execute a subset of the iteration...

Include using System.Numerics and add a reference to System.Numerics to the project. using System; using System.Numerics; namespace Euler_25 { class Program { static void Main(string[] args) { BigInteger l1 = 1; BigInteger l2 = 1; ...

You can re-throw error that you catch in CATCH block using TRHOW statement: DECLARE @msg nvarchar(50) = 'Here is a problem! Area: ''%s'' Line:''%i''' BEGIN TRY print 'First statement'; RAISERROR(@msg, 11, 1, 'TRY BLOCK', 2); print 'Second statement'; END TRY BEGIN CATCH print...

Let's say you have a library that returns callbacks, for example the fs module in NodeJS: const fs = require("fs"); fs.readFile("/foo.txt", (err, data) => { if(err) throw err; console.log(data); }); We want to convert it to a promise returning API, with bluebird - ...

You can convert a single function with a callback argument to a Promise-returning version with Promise.promisify, so this: const fs = require("fs"); fs.readFile("foo.txt", (err, data) => { if(err) throw err; console.log(data); }); becomes: const promisify = requ...

On a 8 cores Linux machine using GCC version 4.4, the C codes can be compiled and run the following way: $ gcc -std=c99 -O3 -fopenmp loop.c -o loopc -lm $ OMP_NUM_THREADS=1 ./loopc Computing 1000000 cosines and summing them with 1 threads took 0.095832s $ OMP_NUM_THREADS=2 ./loopc Computing 100...

Several 'insert' functions can "burn" ids. Here is an example, using InnoDB (other Engines may work differently): CREATE TABLE Burn ( id SMALLINT UNSIGNED AUTO_INCREMENT NOT NULL, name VARCHAR(99) NOT NULL, PRIMARY KEY(id), UNIQUE(name) ) ENGINE=InnoDB; IN...

to check if the given path is a directory dirname = '/home/john/python' os.path.isdir(dirname) to check if the given path is a file filename = dirname + 'main.py' os.path.isfile(filename) to check if the given path is symbolic link symlink = dirname + 'some_sym_link' os.path.islink(symli...

When a base class provides a set of overloaded functions, and a derived class adds another overload to the set, this hides all of the overloads provided by the base class. struct HiddenBase { void f(int) { std::cout << "int" << std::endl; } void f(bool) { std::cout &...

configuration EnableIISFeature { node localhost { WindowsFeature IIS { Ensure = “Present” Name = “Web-Server” } } } If you run this configuration in Powershell (EnableIISFeature), it will produce a localho...

Starting a DSC on a remote machine is almost just as simple. Assuming you've already set up Powershell remoting (or enabled WSMAN). $remoteComputer = "myserver.somedomain.com" $cred = (Get-Credential) Start-DSCConfiguration -ServerName $remoteComputer -Credential $cred -Verbose Nb: A...

Sometimes it can be useful to test your Powershell data files and iterate through the nodes and servers. Powershell 5 (WMF5) added this neat little feature for doing this called Import-PowerShellDataFile . Example: $data = Import-PowerShellDataFile -path .\MydataFile.psd1 $data.AllNodes

To list available DSC resources on your authoring node: Get-DscResource This will list all resources for all installed modules (that are in your PSModulePath) on your authoring node. To list all available DSC resources that can be found in the online sources (PSGallery ++) on WMF 5 : Find-DS...

Before you can use a resource in a configuration, you must explicitly import it. Just having it installed on your computer, will not let you use the resource implicitly. Import a resource by using Import-DscResource . Example showing how to import the PSDesiredStateConfiguration resource and the F...

Do while is very similar to for loop however this generally is used if our loop repetitions is unknown. Do While: 'Continues until i is greater than 10 Do While i <= 10 i = i + 1 Loop 'Or we can write it so the first loop always executes unconditionally: 'Ends after our first loop as...

#!/usr/bin/env python """ An annotated simple socket server example in python. WARNING: This example doesn't show a very important aspect of TCP - TCP doesn't preserve message boundaries. Please refer to http://blog.stephencleary.com/2009/04/message-framing.html before adaptin...

#!/usr/bin/env python """ An annotated simple socket client example in python. WARNING: This example doesn't show a very important aspect of TCP - TCP doesn't preserve message boundaries. Please refer to http://blog.stephencleary.com/2009/04/message-framing.html before adaptin...

Passwords should never be stored as plain text! They should be hashed with a randomly generated salt (to defend against rainbow table attacks) using a slow password hashing algorithm. A high number of iterations (> 10k) can be used to slow down brute force attacks. A delay of ~100ms is acceptable...

Apart from primitives, the Explicit Layout structs (Unions) in C#, can also contain other Structs. As long as a field is a Value type and not a Reference, it can be contained in a Union: using System; using System.Runtime.InteropServices; // The struct needs to be annotated as "Explici...

Get information about the Authenticode signature from a signed script by using the Get-AuthenticodeSignature-cmdlet: Get-AuthenticodeSignature .\MyScript.ps1 | Format-List *