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Python Tutorial

Python HOME Python Intro Python Get Started Python Syntax Python Comments Python Variables Python Data Types Python Numbers Python Casting Python Strings Python Booleans Python Operators Python Lists Python Tuples Python Sets Python Dictionaries Python If...Else Python While Loops Python For Loops Python Functions Python Lambda Python Arrays Python Classes/Objects Python Inheritance Python Iterators Python Scope Python Modules Python Dates Python Math Python JSON Python RegEx Python PIP Python Try...Except Python User Input Python String Formatting

File Handling

Python File Handling Python Read Files Python Write/Create Files Python Delete Files

Python NumPy

NumPy Intro NumPy Getting Started NumPy Creating Arrays NumPy Array Indexing NumPy Array Slicing NumPy Data Types NumPy Copy vs View NumPy Array Shape NumPy Array Reshape NumPy Array Iterating NumPy Array Join NumPy Array Split NumPy Array Search NumPy Array Sort NumPy Array Filter NumPy Random NumPy ufunc

Python SciPy

SciPy Intro SciPy Getting Started SciPy Constants SciPy Optimizers SciPy Sparse Data SciPy Graphs SciPy Spatial Data SciPy Matlab Arrays SciPy Interpolation SciPy Significance Tests

Machine Learning

Getting Started Mean Median Mode Standard Deviation Percentile Data Distribution Normal Data Distribution Scatter Plot Linear Regression Polynomial Regression Multiple Regression Scale Train/Test Decision Tree

Python MySQL

MySQL Get Started MySQL Create Database MySQL Create Table MySQL Insert MySQL Select MySQL Where MySQL Order By MySQL Delete MySQL Drop Table MySQL Update MySQL Limit MySQL Join

Python MongoDB

MongoDB Get Started MongoDB Create Database MongoDB Create Collection MongoDB Insert MongoDB Find MongoDB Query MongoDB Sort MongoDB Delete MongoDB Drop Collection MongoDB Update MongoDB Limit

Python Reference

Python Overview Python Built-in Functions Python String Methods Python List Methods Python Dictionary Methods Python Tuple Methods Python Set Methods Python File Methods Python Keywords Python Exceptions Python Glossary

Module Reference

Random Module Requests Module Statistics Module Math Module cMath Module

Python How To

Remove List Duplicates Reverse a String Add Two Numbers

Python Examples

Python Examples Python Compiler Python Exercises Python Quiz Python Certificate

Python RegEx Sets


RegEx Sets

A set is a set of characters inside a pair of square brackets [] with a special meaning:

Set Description Try it
[arn] Returns a match where one of the specified characters (a, r, or n) are present Try it »
[a-n] Returns a match for any lower case character, alphabetically between a and n Try it »
[^arn] Returns a match for any character EXCEPT a, r, and n Try it »
[0123] Returns a match where any of the specified digits (0, 1, 2, or 3) are present Try it »
[0-9] Returns a match for any digit between 0 and 9 Try it »
[0-5][0-9] Returns a match for any two-digit numbers from 00 and 59 Try it »
[a-zA-Z] Returns a match for any character alphabetically between a and z, lower case OR upper case Try it »
[+] In sets, +, *, ., |, (), $,{} has no special meaning, so [+] means: return a match for any + character in the string Try it »