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Comprehensions & generators

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

3 matches

Count Data in Python with Comprehensions and Generators

Count list items with a dict comprehension and generate squares lazily with a generator expression, printing both results.

comprehensions generators counter

Python

from collections import Counter

data = ["apple", "banana", "apple", "cherry", "banana", "apple"]

counts = {item: data.count(item) for item in set(data)}

square_gen = (x * x for x in range(5))
squares = list(square_gen)

if __name__ == "__main__":
    print("Manual count:", counts)
    print("Counter:", dict(Counter…

15 0 Open

Comprehensions & generators easy

Dict Comprehension to Map Keys to Lengths in Python

Build a dictionary that maps each word to its character count using a dictionary comprehension.

dictionary comprehension len

Python

words = ["apple", "banana", "cherry", "date", "elderberry"]

word_lengths = {word: len(word) for word in words}

print(word_lengths)

14 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

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