Tutorial by Examples: e

Getting Bundle by Path

Locating a Cocoa bundle using its path To obtain the bundle at a specific path using Cocoa, call the bundleWithPath: class method of the NSBundle NSBundle *myBundle; // obtain a reference to a loadable bundle myBundle = [NSBundle bundleWithPath:@"/Library/MyBundle.bundle...

iOS • NSBundle

Docker stats all running containers

sudo docker stats $(sudo docker inspect -f "{{ .Name }}" $(sudo docker ps -q)) Shows live CPU usage of all running containers.

Docker • Docker stats all running containers

Reading from and writing to a file

Before reading and writing text files you should know what encoding to use. See the Perl Unicode Documentation for more details on encoding. Here we show the setting of UTF-8 as the default encoding and decoding for the function open. This is done by using the open pragma near the top of your code (...

Perl Language • File I/O (reading and writing files)

Iterating over nodes

The NodeIterator interface provides methods for iterating over nodes in a DOM tree. Given a document like this one: <html> <body> <section class="main"> <ul> <li>List Item</li> <li>List Item</li> <li>Li...

DOM • Traversal

Removing a class

Modern browsers provide a classList object to ease manipulation of the element's class attribute. Older browsers require direct manipulation of the element's className property. * Note class names are not stored in the element's property in any particular order W3C DOM4 Removing one class from an...

DOM • Manipulating a list of CSS classes

Testing for a class

Modern browsers provide a classList object to ease manipulation of the element's class attribute. Older browsers require direct manipulation of the element's className property. * Note class names are not stored in the element's property in any particular order W3C DOM4 Testing if an element cont...

DOM • Manipulating a list of CSS classes

Ellipse

To plot an ellipse you can use its equation. An ellipse has a major and a minor axis. Also we want to be able to plot the ellipse on different center points. Therefore we write a function whose inputs and outputs are: Inputs: r1,r2: major and minor axis respectively C: center of the ellip...

MATLAB Language • Drawing

Working with columns containg NULL values

In MySQL and other SQL dialects, NULL values have special properties. Consider the following table containing job applicants, the companies they worked for, and the date they left the company. NULL indicates that an applicant still works at the company: CREATE TABLE example (`applicant_id` INT, `...

MySQL • Dealing with sparse or missing data

Prototype Pattern (C++)

class IPrototype { public: virtual ~IPrototype() = default; auto Clone() const { return std::unique_ptr<IPrototype>{DoClone()}; } auto Create() const { return std::unique_ptr<IPrototype>{DoCreate()}; } private: virtual IPrototype* DoClone() const = 0; virt...

Design patterns • Prototype Pattern

Optimizing Storage Layout for InnoDB Tables

In InnoDB, having a long PRIMARY KEY (either a single column with a lengthy value, or several columns that form a long composite value) wastes a lot of disk space. The primary key value for a row is duplicated in all the secondary index records that point to the same row. Create an AUTO_INCREME...

MySQL • Mysql Performance Tips

Safe reseeding

You may want to re-seed your database without affecting your previously created seeds. For this purpose, you can use firstOrCreate in your seeder: EmployeeType::firstOrCreate([ 'type' => 'manager', ]); Then you can seed the database: php artisan db:seed Later, if you want to add a...

Laravel • Seeding

Rationale

The correct invocation of helper modules and functions can be intimidating because these are generated dynamically (e.g., when creating a new project or adding a new resource) they are not documented explicitly (e.g., MyApp.ErrorHelpers.error_tag) the documentation does not cover all examples (...

phoenix-framework • Generate project documentation

Automatically reload vimrc upon save

To automatically reload vimrc upon save, add the following to your vimrc: if has('autocmd') " ignore this section if your vim does not support autocommands augroup reload_vimrc autocmd! autocmd! BufWritePost $MYVIMRC,$MYGVIMRC nested source % augroup END endif a...

vim • Tips and tricks to boost productivity

Adding Siri Extension to App

To integrate Siri capabilities in your app, you should add an extensions as you would do while creating an iOS 10 Widget (old Today View Extension) or a custom keyboard. Adding capability 1- In the project settings, select your iOS app target and go to Capabilities tab 2- Enable the Siri capabili...

iOS • SiriKit

Create an empty dataset based on an existing dataset

Method 1: proc sql; create table foo like sashelp.class; quit; Method 2: proc sql; create table bar as select * from sashelp.class (obs=0); quit; Method 1 should be the preferred option

sas • Proc SQL

SELECT Syntax

PROC SQL options; SELECT column(s) FROM table-name | view-name WHERE expression GROUP BY column(s) HAVING expression ORDER BYcolumn(s); QUIT; Example 1: proc sql; select name ,sex from sashelp.class ; quit; The SELECT statement is specified in this order : 1....

sas • Proc SQL

IF-THEN

DECLARE v_num1 NUMBER(10); v_num2 NUMBER(10); BEGIN v_num1 := 2; v_num2 := 1; IF v_num1 > v_num2 THEN dbms_output.put_line('v_num1 is bigger than v_num2'); END IF; END;

plsql • IF-THEN-ELSE Statement

IF-THEN-ELSE

DECLARE v_num1 NUMBER(10); v_num2 NUMBER(10); BEGIN v_num1 := 2; v_num2 := 10; IF v_num1 > v_num2 THEN dbms_output.put_line('v_num1 is bigger than v_num2'); ELSE dbms_output.put_line('v_num1 is NOT bigger than v_num2'); END IF; END;

plsql • IF-THEN-ELSE Statement

IF-THEN-ELSIF-ELSE

DECLARE v_num1 NUMBER(10); v_num2 NUMBER(10); BEGIN v_num1 := 2; v_num2 := 2; IF v_num1 > v_num2 THEN dbms_output.put_line('v_num1 is bigger than v_num2'); ELSIF v_num1 < v_num2 THEN dbms_output.put_line('v_num1 is NOT bigger than v_num2'); ELSE dbms_out...

plsql • IF-THEN-ELSE Statement

Authorizing Contact Access

Importing the framework Swift import Contacts Objective-C #import <Contacts/Contacts.h> Checking accessibility Swift switch CNContactStore.authorizationStatusForEntityType(CNEntityType.Contacts){ case .Authorized: //access contacts case .Denied, .NotDetermined: //request permissio...

iOS • Contacts Framework