How do I create an arithmetic progression as a list of lists

Question

I want to create a continuous arithmetic progression as a list of lists.

I came up with this solution:

def foo(start: int = 1, end: int = 20, step: int = 4) -> list:
    """Return arithmetic progression as LoL."""
    p = []
    for i in range(start, end, step):
        a = []
        for x in range(i, i+step):
            a.append(x)
        p.append(a)
    return p

>>> foo()
[[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16], [17, 18, 19, 20]]

How pythonic is this approach? Are there more efficient ways to implement this? I assume this could be refactored with a list comprehension. Any other suggestions?

Answer 1

Your solution is fine, but this would be the list comprehension way

def foo(start: int = 1, end: int = 20, step: int = 4) -> list:
    """Return arithmetic progression as LoL."""
    return [list(range(i, i+step)) for i in range(start, end, step)]

It's not any more efficient, so focus on readability