From c5088d2f2af42b5ed5429c4d92cc5a83b7ab25b2 Mon Sep 17 00:00:00 2001 From: Bo Bayles Date: Mon, 21 Jan 2019 11:17:04 -0600 Subject: [PATCH] Add note about padding with windowed --- more_itertools/more.py | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/more_itertools/more.py b/more_itertools/more.py index 66c086fc..237ebf40 100644 --- a/more_itertools/more.py +++ b/more_itertools/more.py @@ -658,6 +658,15 @@ def windowed(seq, n, fillvalue=None, step=1): >>> list(windowed([1, 2, 3, 4, 5, 6], 3, fillvalue='!', step=2)) [(1, 2, 3), (3, 4, 5), (5, 6, '!')] + To slide into the iterable's items, use :func:`chain` to add filler items + to the left: + + >>> iterable = [1, 2, 3, 4] + >>> n = 3 + >>> padding = [None] * (n - 1) + >>> list(windowed(chain(padding, iterable), 3)) + [(None, None, 1), (None, 1, 2), (1, 2, 3), (2, 3, 4)] + """ if n < 0: raise ValueError('n must be >= 0')