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Functions & basics

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

4 matches

Benchmark list append vs comprehension in Python

This micro-benchmark compares the speed of building a list with a for loop and append versus a list comprehension, using the timeit module to get precise timings.

timeit benchmark performance

Python

import timeit

# Build a list of the first 1,000,000 integers using append in a loop
def append_loop(n=1_000_000):
    result = []
    for i in range(n):
        result.append(i)
    return result

# Build the same list using a list comprehension
def comprehension(n=1_000_000):
    return [i for i in range(n)]

if __n…

15 0 Open

Functions & basics easy

Build a Progress Callback Function for Loops in Python

Create a reusable progress callback that receives per-step data and lets callers log or update a UI as a loop runs.

callback loops progress

Python

def run_with_progress(items, desc="Processing", step_callback=None):
    """Run a loop with progress updates via callback."""
    total = len(items)
    for idx, item in enumerate(items):
        # Process the item (simulated work here)
        result = item * 2

        # Build progress data dictionary
        if ste…

16 0 Open

Functions & basics easy

How to Count Items with Default Parameters in Python

Define a Python function that prints each item with a running counter, using default parameters to allow custom start values and step increments.

functions default-parameters loops

Python

def count_items(items, start=0, step=1):
    """Count items in a list with configurable start value and step."""
    count = start
    for item in items:
        print(f"{count}: {item}")
        count += step

if __name__ == "__main__":
    fruits = ["apple", "banana", "cherry"]
    print("Default parameters (start=0…

12 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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