Periodically replacing values in a list

Question

Suppose I have the following list in Python:

my_list = [10] * 95 

Given n, I want to replace any other m elements with zero in my list, while keeping the next n elements.

For example, if n = 3 and m = 2, I want my list to look like:

[10, 10, 10, 0, 0, 10, 10, 10 ,0, 0, ..., 10, 10, 10 , 0, 0] 

If it can't be filled perfectly, as is the case with n = 4 and m = 2, then it's OK if my list looks like this:

[10, 10, 10, 10, 0, 0, ..., 10, 10, 10, 10, 0] 

How should I try to solve this problem?

Answer 1

You could use itertools.cycle to create an endless sequence of [10, 10, 10, 0, 0] and then take the first 95 elements of that sequence with itertools.islice:

n = 3 m = 2  pattern = [10] * n + [0] * m my_list = list(itertools.islice(itertools.cycle(pattern), 95))