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The for keyword is also used for conditional loops, traditionally while loops in other programming languages. package main import ( "fmt" ) func main() { i := 0 for i < 3 { // Will repeat if condition is true i++ fmt.Println(i) } } play ...

In Python 2, when a property raise a error, hasattr will ignore this property, returning False. class A(object): @property def get(self): raise IOError class B(object): @property def get(self): return 'get in b' a = A() b = B() print 'a hasattr get:...

The dynamics of the Geometric Brownian Motion (GBM) are described by the following stochastic differential equation (SDE): I can use the exact solution to the SDE to generate paths that follow a GBM. Given daily parameters for a year-long simulation mu = 0.08/250; sigma = 0.25/sqrt(...

int getListOfFriends(size_t size, int friend_indexes[]) { size_t i = 0; for (; i < size; i++) { friend_indexes[i] = i; } } C99C11 /* Type "void" and VLAs ("int friend_indexes[static size]") require C99 at least. In C11 VLAs are optional. */ void getLis...

Leiningen Note: If you're going to use Leiningen, you first need to download and install JDK 6 or newer. The easiest way to get started with Clojure is to download and install Leiningen, the de facto standard tool to manage Clojure projects. Linux: curl https://raw.githubusercontent.com/technoma...

dnf install erlang elixir

Numpy installation through pypi (the default package index used by pip) generally fails on Windows computers. The easiest way to install on Windows is by using precompiled binaries. One source for precompiled wheels of many packages is Christopher Gohkle's site. Choose a version according to your ...

Django uses migrations to propagate changes you make to your models to your database. Most of the time django can generate them for you. To create a migration, run: $ django-admin makemigrations <app_name> This will create a migration file in the migration submodule of app_name. The first...

Sometimes, migrations generated by Django are not sufficient. This is especially true when you want to make data migrations. For instance, let's you have such model: class Article(models.Model): title = models.CharField(max_length=70) This model already have existing data and now you want ...

Relative positioning moves the element in relation to where it would have been in normal flow .Offset properties: top left right bottom are used to indicate how far to move the element from where it would have been in normal flow. .relpos{ position:relative; top:20px; left:3...

When absolute positioning is used the box of the desired element is taken out of the Normal Flow and it no longer affects the position of the other elements on the page. Offset properties: top left right bottom specify the element should appear in relation to its next non-static containing ...

Sometimes it's not a good practice expose an internal collection since it can lead to a malicious code vulnerability due to it's mutable characteristic. In order to provide "read-only" collections java provides its unmodifiable versions. An unmodifiable collection is often a copy of a mod...

Prerequisites nodejs To install the latest stable release of sails with the command-line tool issue following command: $ sudo npm install sails -g Depending on your OS you might not need to use sudo.

If you are using the default bash prompt on Linux, you should see the name of the virtual environment at the start of your prompt. (my-project-env) user@hostname:~$ which python /home/user/my-project-env/bin/python

In order to specify which version of python the Linux shell should use the first line of Python scripts can be a shebang line, which starts with #!: #!/usr/bin/python If you are in a virtual environment, then python myscript.py will use the Python from your virtual environment, but ./myscript.py...

To help to maintain clean code, Rails follows the principle of DRY. It involves whenever possible, re-using as much code as possible rather than duplicating similar code in multiple places (for example, using partials). This reduces errors, keeps your code clean and enforces the principle of writin...

In Rails, you find yourself looking at controllers, views, and models for your database. To reduce the need for heavy configuration, Rails implements rules to ease up working with the application. You may define your own rules but for the beginning (and for later on) it's a good idea to stick to co...

By default, the various Collection types are not thread-safe. However, it's fairly easy to make a collection thread-safe. List<String> threadSafeList = Collections.synchronizedList(new ArrayList<String>()); Set<String> threadSafeSet = Collections.synchronizedSet(new HashSet<S...

Now that the router is configured and our app knows how to handle the routes, we need to show the actual components that we configured. To do so, configure your HTML template/file for your top-level (app) component like so: //app.ts import {Component} from '@angular/core'; import {Router, ROUT...

git cherry-pick <commit-A>..<commit-B> will place every commit after A and up to and including B on top of the currently checked-out branch. git cherry-pick <commit-A>^..<commit-B> will place commit A and every commit up to and including B on top of the currently checked-out...