Tutorial by Examples: d

Here we first fetch our parent product and the we will get all children products that this parent have. <?php namespace Test\Test\Controller\Test; use Magento\Framework\App\Action\Context; class Products extends \Magento\Framework\App\Action\Action { public function __cons...

Arrays values should be accessed using a number specifying the location of the desired value in the array. This number is called Index. Indexes starts at 0 and finish at array length -1. To access a value, you have to do something like this: arrayName[index], replacing "index" by the num...

class AppDelegate: UIResponder, UIApplicationDelegate { var window: UIWindow? var firstTabNavigationController : UINavigationController! var secondTabNavigationControoller : UINavigationController! var thirdTabNavigationController : UINavigationController! var fourth...

Aggregating with dplyr is easy! You can use the group_by() and the summarize() functions for this. Some examples are given below. CODE: # Aggregating with dplyr library(dplyr) df = data.frame(group=c("Group 1","Group 1","Group 2","Group 2","Group 2&...

Sometimes the download takes longer than the cell is being displayed. In this case it can happen, that the downloaded image is shown in the wrong cell. To fix this we can not use the UIImageView Extension. We still will be using Alamofire however we will use the completion handler to display the im...

var assert = require('assert'); describe('String', function() { describe('#split', function() { it('should return an array', function() { assert(Array.isArray('a,b,c'.split(','))) }); }); });

I have read and watched a lot of different Dagger2 tutorials but most of them are too long or hard to understand so I decided to write a new simple and short tutorial for Dagger2, I hope you like it. Why we need it? Simplifies access to shared instances: It provides a simple way to obtain refere...

var myVariable = "This is a variable!"; This is an example of defining variables. This variable is called a "string" because it has ASCII characters (A-Z, 0-9, !@#$, etc.)

var myArray = []; // empty array An array is a set of variables. For example: var favoriteFruits = ["apple", "orange", "strawberry"]; var carsInParkingLot = ["Toyota", "Ferrari", "Lexus"]; var employees = ["Billy", "Bob...

Let's first brush up with what are the Instance Variables: They behave more like properties for an object. They are initialized on an object creation. Instance variables are accessible through instance methods. Per Object has per instance variables. Instance Variables are not shared between object...

Creating an Snackbar without the need pass view to Snackbar, all layout create in android in android.R.id.content. public class CustomSnackBar { public static final int STATE_ERROR = 0; public static final int STATE_WARNING = 1; public static final int STATE_SUCCESS = 2; publi...

A pointer to a concrete data type, converted to void *, can be used to pass values to and return results from the thread function. #include <stdio.h> #include <stdlib.h> #include <pthread.h> struct thread_args { int a; double b; }; struct thread_result { ...

Rhas a vast collection of built-in datasets. Usually, they are used for teaching purposes to create quick and easily reproducible examples. There is a nice web-page listing the built-in datasets: https://vincentarelbundock.github.io/Rdatasets/datasets.html Example Swiss Fertility and Socioecono...

There are packages that include data or are created specifically to disseminate datasets. When such a package is loaded (library(pkg)), the attached datasets become available either as R objects; or they need to be called with the data() function. Gapminder A nice dataset on the development of c...

Numerous packages are created specifically to access some databases. Using them can save a bunch of time on reading/formating the data. Eurostat Even though eurostat package has a function search_eurostat(), it does not find all the relevant datasets available. This, it's more convenient to brow...

Human Mortality Database Human Mortality Database is a project of the Max Planck Institute for Demographic Research that gathers and pre-process human mortality data for those countries, where more or less reliable statistics is available. # load required packages library(tidyverse) library(ext...

Spaghetti code means a code snippet that uses many, and often confusing structures. Such as GOTOs, exceptions and inconsistent code. Examples and Solutions Example A @echo off set /a counter=0 :Loop set /a counter=%counter% + 1 echo %counter% if %counter% equ 10 goto :exit goto :Loop ...

An entity represents an object of a game like a player figure or an enemy figure. Since this object does not do much without arms and legs we can add the components to this. To create this system apple has the GKEntity and GKComponent classes. Lets assume we have the following classe for the follow...

There are various approach to read a excel file. I'll provide a example with file path parameter. You can get various way to read a file at this post. public void ReadExcel(string path) { // Write data in workbook from xls document. XSSFWorkbook workbook = new XSS...

This is a good step by step guide for setting up asp net Identity and Identity server for authorization and authentication. https://docs.microsoft.com/en-us/aspnet/core/security/authentication/identity You can also follow the official docs examples and IdentityServer4 quickstart samples on Github ...