RegEx
Introduction to Python
Getting Started
Comments
Variables
Data Types
Type Casting
Input and Output
Operators
Strings
Booleans
Conditional Statements
While Loop
For Loop
Loop Control Statements
Lists
Tuples
Sets
Dictionaries
Functions
Function Arguments and Return Values
Variable Scope
Recursion
Lambda Functions
Arrays and Python Lists
Modules
Dates and Math
String Formatting
File Handling
Try and Except
Classes and Objects
Inheritance
Iterators
JSON
RegEx
RegEx
Text Pattern Matching
Definition: A pattern match is a specialized sequence of characters used to search text. Python's built-in re tool allows you to check if text contains specific sequences, search for data, split text, or replace characters.
Why: This is an essential tool for tasks like input validation (checking email styles), data cleaning, and searching large blocks of data.
Common Match Symbols
[0-9]: Matches digits.+: Matches one or more repetitions of the item.[a-zA-Z0-9_]: Matches alphanumeric characters.^: Matches the start of a text area.
Example (Finding Matches)
import re
text = "My number is 98765"
# Find digits
result = re.findall("[0-9]+", text)
print(result) # Output: ['98765']Explanation
- Pattern Search: The search parameters inspect the string from left to right and extract every single matching sequence it finds into a structured Python list.
Key Notes
- Overly complex search layouts can become difficult to read, so document your steps clearly using notes.