Rolling or sliding window iterator?

Question

I need a rolling window (aka sliding window) iterable over a sequence/iterator/generator. Default Python iteration can be considered a special case, where the window length

Answer 1

How about using the following:

mylist = [1, 2, 3, 4, 5, 6, 7]

def sliding_window(l, window_size=2):
    if window_size > len(l):
        raise ValueError("Window size must be smaller or equal to the number of elements in the list.")

    t = []
    for i in xrange(0, window_size):
        t.append(l[i:])

    return zip(*t)

print sliding_window(mylist, 3)

Output:

[(1, 2, 3), (2, 3, 4), (3, 4, 5), (4, 5, 6), (5, 6, 7)]