Tutorial by Examples: basics

Index Creation Basics

See the below transactions collection. > db.transactions.insert({ cr_dr : "D", amount : 100, fee : 2}); > db.transactions.insert({ cr_dr : "C", amount : 100, fee : 2}); > db.transactions.insert({ cr_dr : "C", amount : 10, fee : 2}); > db.transactions.in...

MongoDB • Indexes

Basic Shell Utilities

Customizing the Shell prompt Default command prompt can be changed to look different and short. In case the current directory is long default command prompt becomes too large. Using PS1 becomes useful in these cases. A short and customized command pretty and elegant. In the table below PS1 has be...

GNU/Linux • Shell

Basics

Back references are used to match the same text previously matched by a capturing group. This both helps in reusing previous parts of your pattern and in ensuring two pieces of a string match. For example, if you are trying to verify that a string has a digit from zero to nine, a separator, such as...

Regular Expressions • Back reference

Basic Setup from Official Release

This example goes over how to set up CoreNLP from the latest official release. This example will take you through downloading the package, and running a simple command-line invocation of CoreNLP. Prerequisites: Java JVM 8. The command java -version should complete successfully with a line like: ...

stanford-nlp • Getting started with stanford-nlp

Basic SOQL Query

SELECT Id, Name FROM Account This will return the Id and Name fields from the Account table. No filtering or sorting will be applied.

Salesforce • Salesforce Object Query Language (SOQL)

Visual Format Language Basics: Constraints in Code!

HVFL is a language designed to constrain UI elements in a simple and quick fashion. Generally, VFL has an advantage over traditional UI customization in the Interface Builder because it's much more readable, accessible and compact. Here's an example of VFL, in which three UIViews are constrained f...

iOS • Auto Layout

Basic subscription to Time.every event with 'unsubscribe'

0.18.0 Model is passed to subscriptions which means that every state change can modify subscriptions. import Html exposing ( Html, div, text, button ) import Html.Events exposing ( onClick ) import Time main : Program Never Model Msg main = Html.program { init = init ,...

Elm Language • Subscriptions

Basic Setup from GitHub

This example goes over how to set up CoreNLP from the GitHub repo. The GitHub code has newer features than the official release, but may be unstable. This example will take you through downloading, building, and running a simple command-line invocation of CoreNLP. Prerequisites: Java 8 or newer....

stanford-nlp • Getting started with stanford-nlp

Basics

Variadic functions are created using the ... ellipses syntax in the argument list of the function definition. function id(...) return end If you called this function as id(1, 2, 3, 4, 5) then ... (AKA the vararg list) would contain the values 1, 2, 3, 4, 5. Functions can take required arg...

Lua • Variadic Arguments

Basics

GSP supports the usage of <% %> scriptlet blocks to embed Groovy code (this is discouraged): <html> <body> <% out << "Hello GSP!" %> </body> </html> You can also use the <%= %> syntax to output values, like in JSP: <htm...

grails • GSP

Basics of Higher Order Functions

Review Partial Application before proceeding. In Haskell, a function that can take other functions as arguments or return functions is called a higher-order function. The following are all higher-order functions: map :: (a -> b) -> [a] -> [b] filter :: (a -> Bool) -> [a] ...

Haskell Language • Higher-order functions

Retrieve Basic Server Information

SELECT @@VERSION Returns the version of MS SQL Server running on the instance. SELECT @@SERVERNAME Returns the name of the MS SQL Server instance. SELECT @@SERVICENAME Returns the name of the Windows service MS SQL Server is running as. SELECT serverproperty('ComputerNamePhysicalNetBIOS'...

Microsoft SQL Server • Getting started with Microsoft SQL Server

Basic SFML program

If everything whas been set up correctly, the following snippet will show a window titled "SFML works!" with a green circle: #include <SFML/Graphics.hpp> int main() { sf::RenderWindow window(sf::VideoMode(200, 200), "SFML works!"); sf::CircleShape shape(100.f...

sfml • Getting started with sfml

Basic SELECT from table

Select all columns from some table (system table in this case): SELECT * FROM sys.objects Or, select just some specific columns: SELECT object_id, name, type, create_date FROM sys.objects

Microsoft SQL Server • SELECT statement

Algorithm Basics

Insertion sort is a very simple, stable, in-place sorting algorithm. It performs well on small sequences but it is much less efficient on large lists. At every step, the algorithms considers the i-th element of the given sequence, moving it to the left until it is in the correct position. Graphica...

algorithm • Insertion Sort

Basic settings of Auto-completion and suggestions

Notepad++ provides 2 types of features for auto-completion and suggestions: Auto-completion that reads the open file and provide suggestion of words and/or functions within the file Suggestion with the arguments of functions (specific to the language) To enable it, you need to change a settin...

notepad++ • Auto-completion and suggestion

RxSwift basics

FRP, or Functional Reactive Programming, has some basic terms which you need to know. Every piece of data can be represented as Observable, which is an asynchronous data stream. The power of FRP is in representation synchronous and asynchronous events as streams, Observables, and providing the same...

Swift Language • RxSwift

Tensorflow Basics

Tensorflow works on principle of dataflow graphs. To perform some computation there are two steps: Represent the computation as a graph. Execute the graph. Representation: Like any directed graph a Tensorflow graph consists of nodes and directional edges. Node: A Node is also called an Op(s...

tensorflow • Getting started with tensorflow

Basics: initialize the SPI and a chip select pin, and perform a 1-byte transfer

#include <SPI.h> #define CSPIN 1 void setup() { pinMode(CSPIN, OUTPUT); // init chip select pin as an output digitalWrite(CSPIN, 1); // most slaves interpret a high level on CS as "deasserted" SPI.begin(); SPI.beginTransaction(SPISettings(1000000, MSBFIRST, SPI_MO...

arduino • SPI Communication

Pointer basics

C++11 Note: in all the following, the existence of the C++11 constant nullptr is assumed. For earlier versions, replace nullptr with NULL, the constant that used to play a similar role. Creating a pointer variable A pointer variable can be created using the specific * syntax, e.g. int *pointer_...

C++ • Pointers