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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

13 matches
Comprehensions & generators medium

Build a Generator Pipeline in Python: Filter Then Map

Create a lazy data pipeline by chaining generator functions that read, filter, map, and write data step by step.

generators pipeline lazy-evaluation
Python
def read_data():
    return ["a", "bb", "ccc", "dd", "eeeee", "f"]


def filter_short(words):
    return (word for word in words if len(word) >= 2)


def map_to_upper(words):
    return (word.upper() for word in words)


def write_data(words):
    for word in words:
        print(word)


if __name__ == "__main__":
   …
12 0 Open
Comprehensions & generators easy

Chunk an Iterable into Batches with a Generator in Python

Yield fixed-size batches from any iterable lazily using itertools.islice inside a generator function.

generators iterators itertools
Python
from itertools import islice

def chunked(iterable, size):
    iterator = iter(iterable)
    while True:
        batch = list(islice(iterator, size))
        if not batch:
            break
        yield batch

if __name__ == "__main__":
    data = range(10)
    for batch in chunked(data, 3):
        print(batch)
14 0 Open
Comprehensions & generators easy

Generate Data with Python Comprehensions and Generators

Shows list, dict compregensions and generator expressions plus a Fibonacci generator to produce data lazily.

comprehensions generators lazy-evaluation
Python
# Data generation helpers using comprehensions and generators
from itertools import islice


def fibonacci(limit):
    """Generate Fibonacci numbers up to a limit."""
    a, b = 0, 1
    while a <= limit:
        yield a
        a, b = b, a + b


def main():
    # List comprehension: squares of even numbers
    square…
14 0 Open
Comprehensions & generators easy

How to Create an Infinite Arithmetic Sequence Generator in Python

Build a memory-efficient generator that yields an infinite arithmetic progression and extract the first N values with list comprehension.

generators yield infinite-sequences
Python
"""Count generator infinite arithmetic progression"""


def arithmetic_counter(start=0, step=1):
    """Generate an infinite arithmetic sequence."""
    current = start
    while True:
        yield current
        current += step


if __name__ == "__main__":
    counter = arithmetic_counter(1, 3)
    result = [next(c…
13 0 Open
Comprehensions & generators easy

How to Generate Fibonacci Numbers in Python Without Recursion

Build an efficient infinite Fibonacci sequence using a generator function with O(1) memory and no recursion overhead.

generators fibonacci iteration
Python
def fib(n):
    a, b = 0, 1
    for _ in range(n):
        yield a
        a, b = b, a + b

if __name__ == "__main__":
    count = 10
    result = list(fib(count))
    print(result)
14 0 Open
Comprehensions & generators easy

How to Split Data into Chunks and Use Generators in Python

Split a list into fixed-size chunks with a list comprehension and square even numbers lazily with a generator expression.

comprehensions generators chunking
Python
def split_numbers(data, chunk_size):
    return [data[i:i + chunk_size] for i in range(0, len(data), chunk_size)]


def square_even_numbers(numbers):
    return (n ** 2 for n in numbers if n % 2 == 0)


if __name__ == "__main__":
    sample_data = list(range(1, 21))
    chunks = split_numbers(sample_data, 5)
    print…
14 0 Open
Comprehensions & generators easy

Normalize Data in Python with Comprehensions and Generators

Clean a list by dropping None values with a comprehension, then min-max normalize it using a lazy generator expression — a beginner-friendly data preparation pattern.

comprehensions generators normalization
Python
import statistics

# Sample raw data including missing and outlier-ish values
raw = [22, 18, None, 25, 30, 19, 22, 17, None, 28, 24]

# Clean the data: drop None values using a list comprehension
clean = [x for x in raw if x is not None]

# Normalize using min-max scaling with a generator expression
min_val = min(clea…
12 0 Open
Comprehensions & generators easy

Python Comprehensions and Generators for Beginners

Learn list, dict, and set comprehensions plus generator expressions and generator functions with clear, runnable examples.

comprehensions generators lazy-evaluation
Python
# Demonstrates list comprehensions, dict comprehensions, set comprehensions, and generators

def demonstrate_comprehensions():
    # List comprehension: squares of even numbers
    numbers = range(1, 11)
    even_squares = [n ** 2 for n in numbers if n % 2 == 0]
    
    # Dict comprehension: number to its factorial
 …
14 0 Open
Comprehensions & generators easy

Take n items from an infinite Python generator

Uses itertools.islice to lazily take exactly n items from an infinite generator without exhausting it.

generators itertools islice
Python
from itertools import islice

def count_up_from(start=0):
    n = start
    while True:
        yield n
        n += 1

def take_n(generator, count):
    return list(islice(generator, count))

if __name__ == "__main__":
    gen = count_up_from(10)
    result = take_n(gen, 5)
    print(result)
10 0 Open
Comprehensions & generators easy

Write Data Helpers with Comprehensions and Generators in Python

Demonstrates list, dict, and set comprehensions plus generator expressions and generator functions for building concise data helpers.

comprehensions generators data-helpers
Python
# Basic comprehensions and generators demo

# List comprehension: squares of evens
squares = [x * x for x in range(10) if x % 2 == 0]
print("List comp:", squares)

# Dictionary comprehension: char -> count
text = "hello"
char_counts = {c: text.count(c) for c in set(text)}
print("Dict comp:", char_counts)

# Set compre…
9 0 Open
Concurrency & performance easy

Using a Python Generator Instead of a List to Save Memory

Compare a list approach with a generator to stream values lazily, avoiding memory-heavy storage of large sequences.

generator lazy-evaluation memory
Python
def fibonacci_generator(limit):
    a, b = 0, 1
    count = 0
    while count < limit:
        yield a
        a, b = b, a + b
        count += 1


def sum_first_n(generator, n):
    total = 0
    for i, value in enumerate(generator):
        if i >= n:
            break
        total += value
    return total


if __…
11 0 Open
Big data & Spark medium

Lazy Evaluation Transform Lineage Mock in Python

Build a mock lineage tracker for data transforms using lazy evaluation and function wrappers in Python.

lazy-evaluation lineage decorator
Python
import functools


def lazy_transform(pipeline):
    """Build a mock lineage tracker using lazy evaluation."""
    lineage = []

    def wrap(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            result = func(*args, **kwargs)
            lineage.append({"transform": func.__name__, "a…
15 0 Open
Big data & Spark medium

Mock RDD in Python: Simulate Spark RDD Lazy Transformations

Simulate Apache Spark RDD behavior in Python with lazy maps, filters, partitions, and a collect action.

spark rdd big-data
Python
import random

def mock_rdd(data, num_slices=2):
    """
    A simple simulation of Spark RDD behavior with lazy evaluation,
    transformations, and an action.
    """
    class SimpleRDD:
        def __init__(self, data, num_slices=2):
            self.data = data
            self.num_slices = num_slices
           …
12 0 Open

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