Tutorial by Examples: w

Using the @property decorator for read-write properties

If you want to use @property to implement custom behavior for setting and getting, use this pattern: class Cash(object): def __init__(self, value): self.value = value @property def formatted(self): return '${:.2f}'.format(self.value) @formatted.setter def ...

Python Language • Property Objects

Showcasing all common Angular constructs

The following example shows common AngularJS constructs in one file: <!DOCTYPE html> <html ng-app="myDemoApp"> <head> <style>.started { background: gold; }</style> <script src="https://code.angularjs.org/1.5.8/angular.min.js">&lt...

AngularJS • Getting started with AngularJS

Adding the total rows selected to every row

SELECT your_columns, COUNT(*) OVER() as Ttl_Rows FROM your_data_set idnameTtl_Rows1example52foo53bar54baz55quux5 Instead of using two queries to get a count then the line, you can use an aggregate as a window function and use the full result set as the window. This can be used as a base for fur...

SQL • Window Functions

Setting up a flag if other rows have a common property

Let's say I have this data: Table items idnametag1exampleunique_tag2foosimple42barsimple3bazhello51quuxworld I'd like to get all those lines and know if a tag is used by other lines SELECT id, name, tag, COUNT(*) OVER (PARTITION BY tag) > 1 AS flag FROM items The result will be: idnametag...

SQL • Window Functions

While Loops

var line = 0 var maximum_lines = 5 while (line < maximum_lines) { line = line + 1 println("Line number: " + line) }

Scala Language • While Loops

Do-While Loops

var line = 0 var maximum_lines = 5 do { line = line + 1 println("Line number: " + line) } while (line < maximum_lines) The do/while loop is infrequently used in functional programming, but can be used to work around the lack of support for the break/continue construct, as...

Scala Language • While Loops

Checking out a working copy

To begin making modifications to the project's data, you have to obtain a local copy of the versioned project. Use the command line svn client or your favorite SVN client (TortoiseSVN, for example). Your local copy of the project is called a working copy in Subversion and you get it by issuing the c...

svn • Getting started with svn

Exporting the versioned data (plain download)

If you want to get the versioned project's data, but you don't need any of the version control capabilities offered by Subversion, you could run svn export <URL> command. Here is an example: $ svn export https://svn.example.com/svn/MyRepo/MyProject/trunk As a result, you will get the proje...

svn • Getting started with svn

Updating a working copy

You are not the only person working on the project, right? This means that your colleagues are also making modifications to the project's data. To stay up to date and to fetch the modifications committed by others, you should run svn update command in your working copy. As a result, your working cop...

svn • Getting started with svn

Use IN to return rows with a value contained in a list

This example uses the Car Table from the Example Databases. SELECT * FROM Cars WHERE TotalCost IN (100, 200, 300) This query will return Car #2 which costs 200 and Car #3 which costs 100. Note that this is equivalent to using multiple clauses with OR, e.g.: SELECT * FROM Cars WHERE TotalCos...

SQL • Filter results using WHERE and HAVING

Hello World

A simple application showing the text "Hello World" in the center of the window. import QtQuick 2.3 import QtQuick.Window 2.0 Window { visible: true width: 640 height: 480 title: qsTr("Hello World") //The method qsTr() is used for translations from one la...

qml • Getting started with qml

Pattern Matching With Stable Identifier

In standard pattern matching, the identifier used will shadow any identifier in the enclosing scope. Sometimes it is necessary to match on the enclosing scope's variable. The following example function takes a character and a list of tuples and returns a new list of tuples. If the character existed...

Scala Language • Pattern Matching

Creating a branch through a working copy

When you interact with the remote central repository using your private local workspace -- the working copy -- you can use repository-relative URL instead of direct URL to URL copy to create a new branch: svn copy "^/MyProject/trunk" "^/MyProject/branches/MyNewBranch" -m "C...

svn • Branching, shelving and tagging in Apache Subversion

Making changes in your local working copy

The working copy (WC) is your local and private workspace that you use to interact with the central Subversion repository. You use the working copy to modify the contents of your project and fetch changes committed by others. The working copy contains your project's data and looks and acts like a r...

svn • Getting started with svn

Simple ASDF system with a flat directory structure

Consider this simple project with a flat directory structure: example |-- example.asd |-- functions.lisp |-- main.lisp |-- packages.lisp `-- tools.lisp The example.asd file is really just another Lisp file with little more than an ASDF-specific function call. Assuming your project depends o...

common-lisp • ASDF - Another System Definition Facility

Creating a basic CLOS class without parents

A CLOS class is described by: a name a list of superclasses a list of slots further options like documentation Each slot has: a name an initialization form (optional) an initialization argument (optional) a type (optional) a documentation string (optional) accessor, reader and/or wr...

common-lisp • CLOS - the Common Lisp Object System

For Loop with C-style syntax

The basic format of C-style for loop is: for (( variable assignment; condition; iteration process )) Notes: The assignment of the variable inside C-style for loop can contain spaces unlike the usual assignment Variables inside C-style for loop aren't preceded with $. Example: for (( i = ...

Bash • Control Structures

Removing items from a List within a loop

It is tricky to remove items from a list while within a loop, this is due to the fact that the index and length of the list gets changed. Given the following list, here are some examples that will give an unexpected result and some that will give the correct result. List<String> fruits = new...

Java Language • Collections

Recognizing an audio file using WebSockets in Java

Using the Java-SDK 3.0.1 CountDownLatch lock = new CountDownLatch(1); SpeechToText service = new SpeechToText(); service.setUsernameAndPassword("<username>", "<password>"); FileInputStream audio = new FileInputStream("filename.wav"); RecognizeOpti...

ibm-watson-cognitive • Speech to Text

Transcribing an audio file using WebSockets (Node.js)

This example shows how to use the IBM Watson Speech to Text service to recognize the type of an audio file and produce a transcription of the spoken text in that file. This example requires Speech to Text service credentials and Node.js Install the npm module for the Watson Developer Cloud N...

ibm-watson-cognitive • Speech to Text