Re: itertools.groupby

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Date	Tue, 23 Apr 2013 01:14:39 +1000
Subject	Re: itertools.groupby
From	Chris Angelico <rosuav@gmail.com>
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On Tue, Apr 23, 2013 at 12:49 AM, Oscar Benjamin
<oscar.j.benjamin@gmail.com> wrote:
> Iterators are
> typically preferred over list slicing for sequential text file access
> since you can avoid loading the whole file at once. This means that
> you can process a large file while only using a constant amount of
> memory.

And, perhaps even more importantly, allows you to pipe text in and
out. Obviously some operations (eg grep) lend themselves better to
this than do others (eg sort), but with this it ought at least to
output each group as it comes.

ChrisA

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itertools.groupby Jason Friedman <jsf80238@gmail.com> - 2013-04-20 11:09 -0600
  Re: itertools.groupby Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-21 00:13 +0000
    Re: itertools.groupby Joshua Landau <joshua.landau.ws@gmail.com> - 2013-04-22 04:09 +0100
  Re: itertools.groupby Neil Cerutti <neilc@norwich.edu> - 2013-04-22 14:24 +0000
    Re: itertools.groupby Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-04-22 15:49 +0100
      Re: itertools.groupby Neil Cerutti <neilc@norwich.edu> - 2013-04-22 15:04 +0000
    Re: itertools.groupby Chris Angelico <rosuav@gmail.com> - 2013-04-23 01:14 +1000

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