Tutorial by Examples: s

Factories can be used in conjunction with Inversion of Control (IoC) libraries too. The typical use case for such a factory is when we want to create an object based on parameters that are not known until run-time (such as the current User). In these cases it can be sometimes be difficult (if no...

Enumerating dictionaries allows you to run a block of code on each dictionary key-value pair using the method enumerateKeysAndObjectsUsingBlock:(void (^)(id key, id obj, BOOL *stop))block Example: NSDictionary stockSymbolsDictionary = @{ @"AAPL":...

In [1]: import numpy as np In [2]: import pandas as pd In [3]: df = pd.DataFrame({'A': list('XYZXYZXYZX'), 'B': [1, 2, 1, 3, 1, 2, 3, 3, 1, 2], 'C': [12, 14, 11, 12, 13, 14, 16, 12, 10, 19]}) In [4]: df.groupby('A')['B'].agg({'mean': np.mean, 'standard deviatio...

import pandas.io.sql import pyodbc import pandas as pd Specify the parameters # Parameters server = 'server_name' db = 'database_name' UID = 'user_id' Create the connection # Create the connection conn = pyodbc.connect('DRIVER={SQL Server};SERVER=' + server + ';DATABASE=' + db + '; UID...

Whenever you declare a new rule inside another rule it is called nesting. With basic nesting, as shown below, the nested selector will be compiled as a new CSS selector with all its parents prepended, separated by a space. // SCSS .parent { margin: 1rem; .child { float: left; } ...

Nesting is a very powerful feature, but should be used with caution. It can happen quite easily and quickly, that you start nesting and carry on including all children in a nest, of a nest, of a nest. Let me demonstrate: // SCSS header { // [css-rules] .holder { // [css-rules] ...

Singletons are used to ensure that only one instance of an object is being created. The singleton allows only a single instance of itself to be created which means it controls its creation. The singleton is one of the Gang of Four design patterns and is a creational pattern. Thread-Safe Singleton ...

Variables are used to store a value once which will be used multiple times throughout a Sass document. They are mostly used for controlling things such as fonts and colors but can be used for any value of any property. Sass uses the $ symbol to make something a variable. $font-stack: Helvetica, s...

Just as in Sass, SCSS variables are used to store a value which will be used multiple times throughout a SCSS document. Variables are mostly used to store frequently-used property values (such as fonts and colors), but can be used for any value of any property. SCSS uses the $ symbol to declare a ...

Fourier Transform is probably the first lesson in Digital Signal Processing, it's application is everywhere and it is a powerful tool when it comes to analyze data (in all sectors) or signals. Matlab has a set of powerful toolboxes for Fourier Transform. In this example, we will use Fourier Transfor...

Objective-C [mySwitch setOn:YES]; //or [mySwitch setOn:YES animated:YES]; Swift mySwitch.setOn(false) //or mySwitch.setOn(false, animated: false)

Objective-C mySwitch.backgroundColor = [UIColor yellowColor]; [mySwitch setBackgroundColor: [UIColor yellowColor]]; mySwitch.backgroundColor =[UIColor colorWithRed:255/255.0 green:0/255.0 blue:0/255.0 alpha:1.0]; mySwitch.backgroundColor= [UIColor colorWithWhite: 0.5 alpha: 1.0]; mySwitch.backg...

Objective-C //for off-state mySwitch.tintColor = [UIColor blueColor]; [mySwitch setTintColor: [UIColor blueColor]]; //for on-state mySwitch.onTintColor = [UIColor cyanColor]; [mySwitch setOnTintColor: [UIColor cyanColor]]; Swift //for off-state mySwitch.tintColor = UIColor.blueColor() ...

If your project depends on the external libraries, you should first install them with opam. Assuming your dependencies are foo and bar and the main entry point of your project is foobar.ml you can then build a bytecode executable with ocamlbuild -use-ocamlfind -pkgs 'foo,bar' foobar.byte Warnin...

If your project has no external dependency and has foo.ml as its main entry point, you can compile a bytecode version with ocamlbuild foo.byte To get a native executable, run ocamlbuild foo.native

order allow,deny deny from 255.0.0.0 allow from all This denies access to the IP 255.0.0.0. order allow,deny deny from 123.45.6. allow from all This denies access to all IPs in the range 123.45.6.0 to 123.45.6.255.

The bind attribute can also be applied to derived types: geese.h struct Goose { int flock; float buoyancy; } struct Goose goose_c; geese.f90 use, intrinsic :: iso_c_binding, only : c_int, c_float type, bind(C) :: goose_t integer(c_int) :: flock real(c_float) :: buoyancy e...

In attempt to send a response asynchronously from chrome.runtime.onMessage callback we might try this wrong code: chrome.runtime.onMessage.addListener(function(request, sender, sendResponse) { $.ajax({ url: 'https://www.google.com', method: 'GET', success: functio...

Homebrew You can install Node.js using the Homebrew package manager. Start by updating brew: brew update You may need to change permissions or paths. It's best to run this before proceeding: brew doctor Next you can install Node.js by running: brew install node Once Node.js is installe...

Detailed instructions on getting laravel set up or installed. composer is required for installing laravel easily. There are 3 methods of installing laravel in your system: Via Laravel Installer Download the Laravel installer using composer composer global require "laravel/installer&quo...