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Strings & text

Format, split, join, parse, and clean text — everyday Python string patterns.

4 matches
Strings & text easy

How to Extract Digits Only from a String in Python

This code uses a regular expression to remove all non-digit characters from a mixed string, returning only the digits.

regex string manipulation data cleaning
Python
import re

def extract_digits(text):
    """Return only the digits from the given text as a string."""
    return re.sub(r'\D', '', text)

if __name__ == "__main__":
    mixed = "abc123def456!@#789"
    result = extract_digits(mixed)
    print(result)
12 0 Open
Strings & text easy

How to Filter Text to Only Letters, Numbers, and Spaces in Python

A beginner-friendly function that filters a string to keep only alphabetic characters, digits, and spaces, removing punctuation and symbols.

text-filtering strings beginner
Python
def filter_text(text, keep_alpha=True, keep_digits=True, keep_spaces=True):
    allowed = set()
    if keep_alpha:
        allowed.update("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
    if keep_digits:
        allowed.update("0123456789")
    if keep_spaces:
        allowed.add(" ")
    return "".join(ch f…
11 0 Open
Strings & text easy

How to Mask Credit Card Middle Digits in Python

Mask the middle digits of credit card numbers in a string, keeping only the first 8 and last 4 digits, using regular expressions.

regex string-manipulation security
Python
import re

def mask_credit_card(text: str) -> str:
    pattern = re.compile(r'(\d{4}[-\s]?)(\d{4}[-\s]?)(\d{4}[-\s]?)(\d{4})')
    return pattern.sub(lambda m: m.group(1) + m.group(2) + '****' + m.group(4), text)

if __name__ == "__main__":
    sample = "Card: 1234-5678-9012-3456 and 1111 2222 3333 4444"
    print(mas…
13 0 Open
Strings & text easy

How to Summarize Text Statistics in Python

This function returns basic statistics about a string, including character, word, and sentence counts, plus case and digit counts.

strings text-processing statistics
Python
def summarize_text(text):
    """Return basic statistics about a string."""
    words = text.split()
    return {
        "characters": len(text),
        "words": len(words),
        "sentences": text.count(".") + text.count("!") + text.count("?"),
        "uppercase": sum(c.isupper() for c in text),
        "lowerca…
13 0 Open

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Strings & text — Python code examples

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This page collects strings & text snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.

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Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.