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Functions & basics

Reusable building blocks — parameters, returns, scope, and clear function design.

54 matches

Profile Python functions with cProfile

Profile a Python program with cProfile, capture the stats in memory, and print a sorted performance report.

import cProfile
import pstats
import io


def slow_function():
    total = 0
    for i in range(100000):
        total += i ** 2
    return total


def medium_function():
    return sum(range(10000))


def fast_function():
    return sum(range(100))


def main():
    result1 = slow_function()
    result2 = medium_func…

11 0 Open

Functions & basics easy

Python Filter Function with Default Parameters for Beginners

Create a reusable filter function with default parameters to keep or exclude numbers above or below a threshold.

functions default-parameters filter

Python

def filter_numbers(numbers, threshold=0, reverse=False):
    """Return numbers that pass the threshold filter.

    Args:
        numbers: list of numbers to filter
        threshold: minimum value to keep (default 0)
        reverse: if True, keep numbers below threshold (default False)
    """
    if reverse:
      …

13 0 Open

Functions & basics easy

Python Function Default Parameters Explained with Examples

Learn how to define Python functions with default parameter values and call them with fewer arguments than declared.

functions default-parameters args

Python

def greet(name, greeting="Hello", punctuation="!"):
    return f"{greeting}, {name}{punctuation}"

def calculate_area(length, width=1, unit="sq units"):
    area = length * width
    return f"Area: {area} {unit}"

if __name__ == "__main__":
    print(greet("Alice"))
    print(greet("Bob", "Hi"))
    print(greet("Charl…

14 0 Open

Functions & basics easy

Write a Pure Function Without Side Effects in Python

Defines a pure function that adds one to a number without modifying external state.

pure functions side effects functions

Python

def add_one(x: int) -> int:
    """Adds 1 to the input without modifying any external state."""
    return x + 1

if __name__ == "__main__":
    original = 5
    result = add_one(original)
    print(f"Original: {original}")
    print(f"Result: {result}")
    print(f"Original unchanged: {original}")

12 0 Open

Functions & basics easy

Write a Recursive Factorial Function in Python

Define a recursive factorial function that handles edge cases and returns the product of all positive integers up to n.

recursion factorial functions

Python

def factorial(n):
    """Return the factorial of n using recursion."""
    if n < 0:
        raise ValueError("Factorial is not defined for negative numbers")
    if n == 0 or n == 1:
        return 1
    return n * factorial(n - 1)

if __name__ == "__main__":
    print(factorial(5))

14 0 Open

Functions & basics easy

Compound interest calculator in Python

Compute future investment value with the compound interest formula and a readable year-by-year loop.

math finance functions

Python

def future_value(
    principal: float,
    annual_rate: float,
    years: int,
    compounds_per_year: int = 12,
) -> float:
    """Return balance after compound interest (rounded to cents)."""
    rate_per_period = annual_rate / compounds_per_year
    periods = compounds_per_year * years
    amount = principal * (1 …

55 0 Open

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