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Python Code Samples

Easy snippets you can copy, study, and run in the browser editor.

262 matches
Strings & text easy

How to Sort Text in Python with a Simple Helper Function

A compact helper function that sorts a list of strings or splits a string into words and sorts them alphabetically, with optional reverse ordering.

sorting strings text-processing
Python
def sort_text(data, reverse=False):
    """
    Sort a list of strings (or a single string split into words) alphabetically.
    """
    if isinstance(data, str):
        words = data.split()
    else:
        words = [str(item) for item in data]
    return sorted(words, reverse=reverse)


if __name__ == "__main__":
 …
11 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
Strings & text easy

How to Transform Text in Python with a Helper Function

Build a simple Python helper to strip extra whitespace and convert text to upper, lower, or title case.

strings text helper
Python
def transform_text(text, upper=False, lower=False, strip_whitespace=False, title_case=False):
    """Apply common string transformations for beginners."""
    result = text

    if strip_whitespace:
        result = " ".join(result.split())

    if upper and lower:
        raise ValueError("Cannot apply both upper and…
12 0 Open
Strings & text easy

How to Truncate a String with Ellipsis in Python

A function that shortens text to a maximum length and appends an ellipsis when truncation occurs, handling edge cases.

strings truncation text-processing
Python
def truncate_with_ellipsis(text: str, max_length: int) -> str:
    """Truncate text to max_length, appending ellipsis if truncated."""
    if len(text) <= max_length:
        return text
    if max_length <= 3:
        return text[:max_length]
    return text[: max_length - 3] + "..."

if __name__ == "__main__":
    t…
11 0 Open
Strings & text easy

How to Validate Text Input in Python: A Simple Text Processor

A Python function that validates a text string by trimming whitespace, then returns a dictionary with character, word, and sentence counts.

text-validation strings input-checking
Python
def validate_text(text: str) -> dict:
    """Analyze a text string and return basic validation statistics."""
    stripped = text.strip()
    if not stripped:
        return {
            "valid": False,
            "reason": "Text is empty or only whitespace",
            "characters": 0,
            "words": 0,
    …
11 0 Open
Strings & text easy

How to Validate Text Strings in Python

Validate strings with a reusable helper that checks type, length limits, and empty string handling.

validation strings helper-function
Python
def is_valid_text(value, min_length=1, max_length=None, allow_empty=False):
    """
    Validate if a value is a string and meets length requirements.
    
    Args:
        value: The value to validate
        min_length: Minimum allowed length (default 1)
        max_length: Maximum allowed length (None = no limit)
…
13 0 Open
Strings & text easy

How to build a text helper in Python for beginners

This code provides easy-to-use functions for cleaning text, removing punctuation, counting word frequencies, and summarizing strings — perfect for beginners.

string-manipulation text-processing word-count
Python
def clean_text(text: str) -> str:
    """Clean and normalize a text string."""
    text = text.strip()
    text = text.replace("  ", " ")
    text = text.capitalize()
    text = text.replace(".", ".")
    return text


def remove_punctuation(text: str) -> str:
    """Remove common punctuation marks from a string."""
 …
12 0 Open
Strings & text easy

Python String Helper Functions for Beginners

A set of beginner-friendly Python functions that count words, reverse text, convert to title case, strip punctuation, and compute character frequency from a string.

strings text-processing word-count
Python
def count_words(text):
    """Count the number of words in a string."""
    return len(text.split())


def reverse_text(text):
    """Reverse the entire string."""
    return text[::-1]


def title_case(text):
    """Capitalize the first letter of each word."""
    return text.title()


def remove_punctuation(text):
 …
14 0 Open
Strings & text easy

Python String isalpha() Method: Check if String is Alphabetic

This code defines a function that uses Python's str.isalpha() method to determine if a string contains only alphabetic characters, with a demonstration on several test strings.

string isalpha validation
Python
def is_alphabetic(s):
    return s.isalpha()

if __name__ == "__main__":
    test_strings = ["Hello", "Hello123", "World!", "Python", ""]
    for s in test_strings:
        print(f"{s!r}: {is_alphabetic(s)}")
13 0 Open
Strings & text easy

String helpers in Python: stats, reverse, and remove vowels

Three beginner-friendly Python functions compute text statistics, reverse word order, and strip vowels from a string.

string-manipulation text-stats vowel-removal
Python
def text_stats(text: str) -> dict:
    """Return basic statistics for a given text string."""
    words = text.split()
    return {
        "characters": len(text),
        "words": len(words),
        "sentences": text.count(".") + text.count("!") + text.count("?"),
        "uppercase": sum(1 for c in text if c.isupp…
14 0 Open
Strings & text easy

Text Processor Functions for Beginners in Python

Demonstrates simple text-processing utilities: word counting, word reversal, whitespace normalization, and lowercase conversion using basic string methods.

text-processing string-methods word-count
Python
def count_words(text):
    """Return the number of words in a string."""
    return len(text.split())

def reverse_words(text):
    """Return the text with words in reverse order."""
    return ' '.join(text.split()[::-1])

def remove_extra_spaces(text):
    """Return text with extra whitespace collapsed to a single s…
13 0 Open
Strings & text easy

Validate email format with regex in Python

A Python function using a regex pattern to validate simple email formats, returning True or False for each input.

regex email validation
Python
import re

def is_valid_email(email):
    pattern = r'^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$'
    return bool(re.match(pattern, email))

if __name__ == "__main__":
    test_emails = [
        "user@example.com",
        "first.last@sub.domain.org",
        "invalid-email",
        "user@.com",
        "user@…
12 0 Open
Lists & loops easy

Check if List is Sorted Ascending in Python

Verify that a list is sorted in ascending order using the all() function and a generator expression.

lists sorted all
Python
def is_sorted_ascending(lst):
    return all(lst[i] <= lst[i + 1] for i in range(len(lst) - 1))

if __name__ == "__main__":
    test_lists = [
        [1, 2, 3, 4, 5],
        [1, 3, 2, 4, 5],
        [5, 4, 3, 2, 1],
        [1, 1, 2, 2, 3],
        [10],
        []
    ]
    for lst in test_lists:
        print(f"{l…
19 0 Open
Lists & loops easy

Enumerate a Python List with a Custom Start Index

Iterate over a list with an index that starts at a custom value (like 5) using Python's built-in enumerate() function with the start parameter.

enumerate iteration loops
Python
fruits = ["apple", "banana", "cherry", "date"]

for index, fruit in enumerate(fruits, start=5):
    print(f"{index}: {fruit}")
15 0 Open
Lists & loops easy

Find Minimum Value in a List in Python

This code defines a function that finds and returns the minimum value in a list of numbers, handling empty lists gracefully by returning None.

minimum lists iteration
Python
def find_minimum(numbers):
    """
    Find and return the minimum value in a list of numbers.
    
    Args:
        numbers: List of numeric values
        
    Returns:
        The minimum value, or None if the list is empty
    """
    if not numbers:
        return None
    min_value = numbers[0]
    for num in n…
12 0 Open
Lists & loops easy

Generate Data Helper for Beginners in Python

Define two functions that create a random list of integers and then compute basic summary statistics like count, total, average, maximum, and minimum using simple loops.

random loops lists
Python
from random import randint

def build_dataset(size: int, max_val: int) -> list[int]:
    data = []
    for _ in range(size):
        data.append(randint(1, max_val))
    return data

def summarize(data: list[int]) -> dict[str, float]:
    total = 0
    maximum = data[0]
    minimum = data[0]
    for value in data:
   …
12 0 Open
Lists & loops easy

How to Calculate the Average of a List of Numbers in Python

Compute the arithmetic mean of a numeric list using Python's built-in sum() and len() functions, returning 0.0 for an empty list.

average mean sum
Python
def calculate_average(numbers):
    if not numbers:
        return 0.0
    return sum(numbers) / len(numbers)

if __name__ == "__main__":
    sample_numbers = [10, 20, 30, 40, 50]
    result = calculate_average(sample_numbers)
    print(f"Average: {result}")
13 0 Open
Lists & loops easy

How to Check if a List is Sorted in Descending Order in Python

This code defines a function that returns True if a given list is sorted in descending order, using a generator expression with all() to compare each adjacent pair.

sorted descending list
Python
def is_descending(lst):
    """Return True if list is sorted in descending order."""
    return all(lst[i] >= lst[i + 1] for i in range(len(lst) - 1))


if __name__ == "__main__":
    test_cases = [
        [5, 4, 3, 2, 1],
        [3, 3, 2, 1],
        [1, 2, 3],
        [10, 8, 9],
        []
    ]

    for case in …
13 0 Open
Lists & loops easy

How to Count, Double, and Find Max in a Python List

Three beginner-friendly Python functions that count even numbers, double each value, and find the maximum in a list using simple loops.

lists loops beginner
Python
def count_even_numbers(numbers):
    """Return the count of even numbers in a list."""
    count = 0
    for num in numbers:
        if num % 2 == 0:
            count += 1
    return count


def double_values(numbers):
    """Return a new list with each value doubled."""
    doubled = []
    for num in numbers:
     …
14 0 Open
Lists & loops easy

How to Filter Even Numbers and Square Them in Python

Create two beginner-friendly helper functions that filter even numbers and compute squares of a number list using loops, then print the results along with the sum and average.

loops filtering math
Python
def get_even_numbers(numbers):
    evens = []
    for num in numbers:
        if num % 2 == 0:
            evens.append(num)
    return evens

def get_squares(numbers):
    squares = []
    for num in numbers:
        squares.append(num ** 2)
    return squares

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

even_numbers …
15 0 Open
Lists & loops easy

How to Find the Maximum Value in a Python List

This code defines a function that finds the largest number in a list by iterating through it, returning None for an empty list, and demonstrates it on a sample list.

max list loop
Python
def find_max(numbers):
    if not numbers:
        return None
    max_value = numbers[0]
    for num in numbers[1:]:
        if num > max_value:
            max_value = num
    return max_value

if __name__ == "__main__":
    sample_list = [3, 7, 2, 9, 1, 9]
    result = find_max(sample_list)
    print(f"Maximum valu…
15 0 Open
Lists & loops easy

How to Flatten a Deeply Nested List in Python Recursively

A recursive function that flattens arbitrarily deep nested lists into a single flat list using isinstance checks.

recursion flatten lists
Python
def flatten(nested_list):
    if not nested_list:
        return []
    if isinstance(nested_list[0], list):
        return flatten(nested_list[0]) + flatten(nested_list[1:])
    return [nested_list[0]] + flatten(nested_list[1:])


if __name__ == "__main__":
    data = [1, [2, [3, [4, [5]]]], [6, [7, [8, [9]]]], 10]
 …
13 0 Open
Lists & loops easy

How to Normalize a List of Numbers in Python

This Python function normalizes a list of numeric values to the range [0, 1] using min-max scaling, returning a new list and leaving the original unchanged.

lists loops normalization
Python
def normalize(data):
    """
    Normalize a list of numeric values to the range [0, 1].
    Returns a new list, leaving the original unchanged.
    """
    if not data:
        return []
    
    min_val = min(data)
    max_val = max(data)
    
    # Handle the edge case where all values are identical
    if min_val …
17 0 Open
Lists & loops easy

How to Pad a List to Length n in Python with a Fill Value

Create a reusable function that pads a Python list to a specified length n by appending a fill value, or truncates it when the list is already longer than n.

lists padding slicing
Python
def pad_list(lst, n, fill_value=None):
    """
    Pad a list to length n using fill_value for missing elements.
    If the list is longer than n, it is truncated to length n.
    """
    if n <= len(lst):
        return lst[:n]
    return lst + [fill_value] * (n - len(lst))


if __name__ == "__main__":
    # Examples…
14 0 Open

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