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From: Vito De Tullio <vito.detullio@gmail.com>
Subject: Re: learning to use iterators
Date: Wed, 24 Dec 2014 16:12:01 +0100
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Xref: csiph.com comp.lang.python:82892

Seb wrote:

>>>> def n_grams(a, n):
> ...     z = (islice(a, i, None) for i in range(n))
> ...     return zip(*z)
> ...
> 
> I'm impressed at how succinctly this islice helps to build a list of
> tuples with indices for all the required windows.

If you want it succinctly, there is this variation on the theme:

n_grams = lambda a, n: zip(*(a[i:] for i in range(n)))


-- 
By ZeD