Tutorial by Examples: i

Hello Web (Basic "Hello World"-type setup)

<html> <head> <script src="https://code.jquery.com/jquery-3.1.0.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script> <script src="https:...

backbone.js • Getting started with backbone.js

Reading the response

response = requests.get("https://api.github.com/events") text_resp = response.text JSON response: for json-formatted responses the package provides a built-in decoder response = requests.get('https://api.github.com/events') json_resp = response.json() This method will raise a Valu...

python-requests • Getting started with python-requests

Reading status codes

The attribute status_code contains the status code of the response good_req = requests.get('https://api.github.com/events') code_200 = good_req.status_code notfound_req = requests.get('https://api.github.com/not_found') code_404 = notfound_req.status_code requests.codes.__dict__ will provid...

python-requests • Getting started with python-requests

Generating model from database

In Visual Studio go to your Solution Explorer then click on Project you will be adding model Right mouse. Choose ADO.NET Entity Data Model Then choose Generate from database and click Next in next window click New Connection... and point to the database you want to generate model from (Could be M...

Entity Framework • Database first model generation

Animate an Image

class AnimatedImage extends Component { constructor(props){ super(props) this.state = { logoMarginTop: new Animated.Value(200) } } componentDidMount(){ Animated.timing( this.state.logoMarginTop, { toValue: 100 ...

react-native • Animation API

Installation or Setup

We have 2 way, we can install Universal app in windows 10 devices (OS/Phone). One app works for both mobile and OS 1 Install using Power Shell command Step 1: Make sure app not have any error and developed, then right click on Universal app project in solution explorer. Step 2: Select Store and C...

win-universal-app • Getting started with win-universal-app

Deferring operations using $q.defer

We can use $q to defer operations to the future while having a pending promise object at the present, by using $q.defer we create a promise that will either resolve or reject in the future. This method is not equivalent of using the $q constructor, as we use $q.defer to promisify an existing routin...

AngularJS • Angular promises with $q service

CSS3 :in-range selector example

CSS • Selectors

Even more specific loop targeting

Let's say we want to change main loop, only for specific taxonomy, or post type. Targeting only main loop on book post type archive page. add_action( 'pre_get_posts', 'my_callback_function' ); function my_callback_function( $query ) { if( !$query->is_main_query() || is_admin() ) return;...

WordPress • Alternating main loop (pre_get_posts filter)

Pre get posts filter basic usage

Sometimes you would like to change main WordPress query. Filter pre_get_posts is the way to go. For example using pre_get_posts you can tell main loop to show only 5 posts. Or to show posts only from one category, or excluding any category etc. add_action( 'pre_get_posts', 'my_callback_function' ...

WordPress • Alternating main loop (pre_get_posts filter)

Exclude category from posts list edit share

add_action( 'pre_get_posts', 'single_category_exclude' ); function single_category_exclude( $query ) { if( !$query->is_main_query() || is_admin() ) return; $query->set( 'cat', '-1' ); return; }

WordPress • Alternating main loop (pre_get_posts filter)

Change posts_per_page for main loop

All we need to do is to use set() method of $query object. It takes two arguments, first what we want to set and second what value to set. add_action( 'pre_get_posts', 'change_posts_per_page' ); function change_posts_per_page( $query ) { if( !$query->is_main_query() || is_admin() ) retu...

WordPress • Alternating main loop (pre_get_posts filter)

Checking if an Email Address appears in a list of addresses

Let's say you need to check if an email address appears in a long list of email addresses. Use the MATCH function to return the row number on which the email address can be found. If there is no match, the function returns an #N/A error. =MATCH(F2,$D$2:$D$200,0) The value you're retrieving ...

excel • MATCH function

Transaction In a TRY/CATCH

This will rollback both inserts due to an invalid datetime: BEGIN TRANSACTION BEGIN TRY INSERT INTO dbo.Sale(Price, SaleDate, Quantity) VALUES (5.2, GETDATE(), 1) INSERT INTO dbo.Sale(Price, SaleDate, Quantity) VALUES (5.2, 'not a date', 1) COMMIT TRANSACTION END TRY BEG...

SQL • TRY/CATCH

Upcasting

The as operator will cast to a supertype. As it cannot fail, it does not return an optional. let name = "Ringo" let value = string as Any // `value` is of type `Any` now

Swift Language • Type Casting

Singleton (Java)

Singletons in Java are very similar to C#, being as both languages are object orientated. Below is an example of a singleton class, where only one version of the object can be alive during the program's lifetime (Assuming the program works on one thread) public class SingletonExample { priva...

Design patterns • Singleton

Plotting The Regression (base)

Continuing on the mtcars example, here is a simple way to produce a plot of your linear regression that is potentially suitable for publication. First fit the linear model and fit <- lm(mpg ~ wt, data = mtcars) Then plot the two variables of interest and add the regression line within the d...

R Language • Linear Models (Regression)

Getting maximum and minimum

The Math.max() function returns the largest of zero or more numbers. Math.max(4, 12); // 12 Math.max(-1, -15); // -1 The Math.min() function returns the smallest of zero or more numbers. Math.min(4, 12); // 4 Math.min(-1, -15); // -15 Getting maximum and minimum from an array: var ...

JavaScript • Arithmetic (Math)

Using constants

To use the constant simply use its name: if (EARTH_IS_FLAT) { print "Earth is flat"; } print APP_ENV_UPPERCASE; or if you don't know the name of the constant in advance, use the constant function: // this code is equivalent to the above code $const1 = "EARTH_IS_FLAT&quo...

PHP • Constants

Case insensitive switch

Java SE 7 switch itself can not be parameterised to be case insensitive, but if absolutely required, can behave insensitive to the input string by using toLowerCase() or toUpperCase: switch (myString.toLowerCase()) { case "case1" : ... break; case &...

Java Language • Strings