Total python Regular Expression saving half an hour

python Regular Expression

In this article, you will be able to learn more about Python Regular Expression here, including all kinds of features like the definition of RegEx, RegEx modules, RegEx function, metacharacter, python RegEx sets, and more. Stay here to learn more Python Regular Expression Basic to advance the process.

A regular expression is a unique sequence of characters that reference search patterns. When a string contains a different search pattern at that point, Regular Expression can be used in RegEx. 

All patterns and strings to be searched for Unicode 8 bit strings. Here the python re modules gives regular Expression support.

Example of Regular Expression in python – 

^p . . . x$

This example defines a RegEx pattern, all are string data that starts with p and ends x. 

Regular Expression 

Python Regular Expression modules

Python has a built-in system that calls re. It can be used to work Regular Expression. For your acquiring knowledge here import re module.

Import re 

Regular Expression in Python

Complete the RegEx system re module then you can start using regular expressions. 

Example of Regular Expression-

import re

#Check if the string starts with “WigMarketing” and ends with “Solution”:

txt = “WigMarketing Digital Solution”

a = re.search(“^WigMarketing.*Solution$”, txt)

if a:

  print(“YES! We have a match!”)

else:

  print(“No match”)

The output of this RegEx

Python Regular expression Function

RegEx provides re modules that help to search match strings. Here I share some RegEx functions with explanations. See these functions –

  • Sub – Sub function replace one or many matching value with strings
  • Search -it helps to returns result a match object
  • Findall – findall function provide all matching value

Python Regular Expression metacharacters

Every metacharacter has a special meaning. That is shown below – 

CharacterMeaningExample
[ ]Character sets [“a-s”]
.Any character“wel….e”
/Special sequence signal“/d”
^Starts with“^welcome”
$Ends with“moon$”
*Zero or more occurrences“wel.*e”
+One or more occurrences“wel.+e”
( )Capture and Group“falls| stays”
{ }All the same separate number of occurrences“Wel.{ 4 }e”

Python RegEx Sets

Python set is a package of sets that contain special characters with meaning. Here I include the most usable sets in python RegEx. 

  • [ arn ] – return a match result when one of the separate character include ( a, r, or n)
  • [0-9 ] – return a matching result between 0-9.
  • [ a-z, A-Z ] – feedback matches any character alphabetically between a and z, lower case or upper case.
  • [ + ] – return a match for any + character that will be a string value.

RegEx Search () function

This function always searches for string data for matching and provides a match object. If showing more than match value it returns only the first matching value. 

Example of Search ( ) function-

import re

txt = “WigMarketing Digital Solution”

a = re.search(“\s”, txt)

print(“The first white-space character is located in position:”, a.start()) 

Output of this code –

Match objects

A matching object is an object that contains the search result. An important point to you when no object finds out matches its return result is that value is None. Have any object match it return result give you instantly.

Example of the match objects – 

import re

#The search() function returns a Match object:

txt = “WigMarketing Digital Solution”

a = re.search(“ti”, txt)

print(a)

The output –

Basically, python regular expressions are used to identify the return value of any kind of strings character. When we want to create single or multiple results at a time, it helps to provide this. To learn more about the advanced level of python regular expression stay here and see my next article. 

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