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Comprehensions & generators

List/dict/set comprehensions, generator expressions, and lazy iteration.

5 matches

Convert Data in Python with Comprehensions and Generators

Convert mixed data to integers, filter and transform numbers, and extract fields from dicts using list comprehensions and generator expressions.

comprehensions generators list-comprehension

Python

def convert_numbers(data):
    """Convert a list of mixed values into integers using a comprehension."""
    return [int(item) for item in data if item is not None]


def double_even_numbers(numbers):
    """Double only even numbers using a generator expression."""
    return (n * 2 for n in numbers if n % 2 == 0)


d…

16 0 Open

Comprehensions & generators easy

Generator Function to Yield an Infinite Counter in Python

This code demonstrates a generator function that yields an infinite sequence of integers starting from a given value, allowing lazy, memory-efficient iteration.

generators infinite sequences yield

Python

def infinite_counter(start=0):
    count = start
    while True:
        yield count
        count += 1

if __name__ == "__main__":
    counter = infinite_counter(5)
    for _ in range(5):
        print(next(counter))

14 0 Open

Comprehensions & generators easy

How to Generate a Collatz Sequence in Python

Generate the Collatz sequence for a given positive integer by repeatedly applying the 3n+1 rule until reaching 1.

collatz sequence loops

Python

def collatz_sequence(n):
    if n <= 0:
        raise ValueError("n must be a positive integer")
    sequence = [n]
    while n != 1:
        if n % 2 == 0:
            n = n // 2
        else:
            n = 3 * n + 1
        sequence.append(n)
    return sequence

if __name__ == "__main__":
    start = 7
    result…

14 0 Open

Comprehensions & generators easy

How to Use List Comprehensions and Generators to Transform Data in Python

Transform a list of integers by squaring even numbers with a list comprehension and cubing odd numbers with a generator.

comprehensions generators list-comprehension

Python

def transform_data(data):
    """
    Transform a list of integers:
    - squares of even numbers using a list comprehension
    - cubes of odd numbers using a generator
    """
    squares = [num ** 2 for num in data if num % 2 == 0]
    cubes = (num ** 3 for num in data if num % 2 != 0)
    return squares, cubes


i…

15 0 Open

Comprehensions & generators easy

Sum of Squares with a Generator Expression in Python

This code computes the sum of squares of integers from 1 to n using a generator expression, demonstrating a memory-efficient and concise way to aggregate a sequence.

generator sum squares

Python

def sum_of_squares(n):
    return sum(x * x for x in range(1, n + 1))

if __name__ == "__main__":
    print(f"Sum of squares from 1 to 5: {sum_of_squares(5)}")
    print(f"Sum of squares from 1 to 10: {sum_of_squares(10)}")

14 0 Open

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