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When developing several applications on one machine, it becomes useful to separate out dependencies into virtual environments. With the use of virtualenv, these environments are sourced into your shell so that when you run a command, it comes from that virtual environment. This is most commonly in...

Joining a subquery is often used when you want to get aggregate data from a child/details table and display that along with records from the parent/header table. For example, you might want to get a count of child records, an average of some numeric column in child records, or the top or bottom row ...

In ASP.NET Core there are several different ways we can localize/globalize our app. It's important to pick a way that suits your needs. In this example you'll see how we can make a multilingual ASP.NET Core app that reads language specific strings from .json files and store them in memory to provi...

brew install mpich

brew install open-mpi

There are two ways to define functions with multiple parameters in F#, Curried functions and Tupled functions. let curriedAdd x y = x + y // Signature: x:int -> y:int -> int let tupledAdd (x, y) = x + y // Signature: x:int * y:int -> int All functions defined from outside F# (such as ...

The term 'heap' is a general computing term meaning an area of memory from which portions can be allocated and deallocated independently of the memory provided by the stack. In C++ the Standard refers to this area as the Free Store which is considered a more accurate term. Areas of memory allocate...

A std::string containing a number can be converted into an integer type, or a floating point type, using conversion functions. Note that all of these functions stop parsing the input string as soon as they encounter a non-numeric character, so "123abc" will be converted into 123. The s...

Arithmetic operations are performed elementwise on Numpy arrays. For arrays of identical shape, this means that the operation is executed between elements at corresponding indices. # Create two arrays of the same size a = np.arange(6).reshape(2, 3) b = np.ones(6).reshape(2, 3) a # array([0, 1...

import random probability = 0.3 if random.random() < probability: print("Decision with probability 0.3") else: print("Decision with probability 0.7")

Installing aws cli in Ubuntu / Debian Instance sudo apt-get install -y python-dev python-pip sudo pip install awscli aws --version aws configure Installing aws cli using python Using pip you can install aws cli in windows, OS X and Linux sudo pip install awscli Configuring the AWS Comman...

Unit Test Unit tests are used to ensure that your code has no syntax error and to test the logic of your code to work as what you expected. Quick example: src/AppBundle/Calculator/BillCalculator.php <?php namespace AppBundle\Calculator; use AppBundle\Calculator\TaxCalculator; class Bi...

Controlled form components are defined with a value property. The value of controlled inputs is managed by React, user inputs will not have any direct influence on the rendered input. Instead, a change to the value property needs to reflect this change. class Form extends React.Component { con...

Uncontrolled components are inputs that do not have a value property. In opposite to controlled components, it is the application's responsibility to keep the component state and the input value in sync. class Form extends React.Component { constructor(props) { super(props); th...

JSTL is part of the Java EE API and included in Java EE application servers such as WildFly, TomEE, GlassFish, but not in barebones servletcontainers such as Tomcat and Jetty. JSTL are the taglibs which you import from http://java.sun.com/jsp/jstl/* namespace. JSTL must not be confused with a "...

There are various methods available for explicitly converting a string to an integer, such as: Convert.ToInt16(); Convert.ToInt32(); Convert.ToInt64(); int.Parse(); But all these methods will throw a FormatException, if the input string contains non-numeric characters. For t...

Objective-C NSString *textToShare = @"StackOverflow Documentation!! Together, we can do for Documentation what we did for Q&A."; NSURL *documentationURL = [NSURL URLWithString:@"http://stackoverflow.com/tour/documentation"]; NSArray *objectsToShare = @[textToShare, docum...

Steps to create Hello Spring: Investigate Spring Boot to see if that would better suit your needs. Have a project set up with the correct dependencies. It is recommended that you are using Maven or Gradle. create a POJO class, e.g. Employee.java create a XML file where you can define your clas...

You can remove any of the conventions defined in the System.Data.Entity.ModelConfiguration.Conventions namespace, by overriding OnModelCreating method. The following example removes PluralizingTableNameConvention. public class EshopContext : DbContext { public DbSet<Product> Products...

for comprehensions in Scala are just syntactic sugar. These comprehensions are implemented using the withFilter, foreach, flatMap and map methods of their subject types. For this reason, only types that have these methods defined can be utilized in a for comprehension. A for comprehension of the fo...