Sliding window for iterables.

sliding_window.py

from itertools import islice

# Slides through iterable each `n` elements.
#
# Sample usage:
#
#   >>> list(sliding_window([1, 2, 3, 4]))
#   [(1, 2), (2, 3), (3, 4)]
#
#   >>> list(sliding_window([1, 2, 3]))
#   [(1, 2), (2, 3)]
#
#   >>> list(sliding_window([1, 2, 3, 4], n=3))
#   [(1, 2, 3), (2, 3, 4)]
#
def sliding_window(iterable, n=2):
    args = [islice(iter(iterable), i, None) for i in range(n)]
    return zip(*args)