Python RegEx

Python RegEx

A RegEx, or Regular Expression, is a sequence of characters that forms a search pattern. RegEx can be used to check if a string contains the specified search pattern. Python has a built-in package called re, which can be used to work with Regular Expressions.

RegEx Module

Python has a built-in package called re, which can be used to work with Regular Expressions. Import the re module:

import re

RegEx in Python

When you have imported the re module, you can start using regular expressions:

import re

txt = "The rain in Spain"
x = re.search("^The.*Spain$", txt)

The findall() Function

The findall() function returns a list containing all matches:

import re

txt = "The rain in Spain"
x = re.findall("ai", txt)
print(x)

The search() Function

The search() function searches the string for a match, and returns a Match object if there is a match:

import re

txt = "The rain in Spain"
x = re.search("\s", txt)

print("The first white-space character is located in position:", x.start())

The split() Function

The split() function returns a list where the string has been split at each match:

import re

txt = "The rain in Spain"
x = re.split("\s", txt)
print(x)