Re: efficient partial sort in Python ?

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From	Ian Kelly <ian.g.kelly@gmail.com>
Date	Tue, 19 Aug 2014 18:00:58 -0600
Subject	Re: efficient partial sort in Python ?
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On Tue, Aug 19, 2014 at 5:05 PM, Dan Stromberg <drsalists@gmail.com> wrote:
> When you use heapq, are you putting all the values in the heap, or
> just up to n at a time (evicting the worst value, one at a time as you
> go)?  If you're doing the former, it's basically a heapsort which
> probably won't beat timsort.  If you're doing the latter, that should
> be pretty good.

The latter is what the heapq.nsmallest and heap.nlargest functions do.
nsmallest uses a max heap, so the value being evicted is still found
at index 0.

Curious then if it's performing worse memory-wise than sorted.

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Thread

efficient partial sort in Python ? Chiu Hsiang Hsu <wdv4758h@gmail.com> - 2014-08-18 10:18 -0700
  Re: efficient partial sort in Python ? Ian Kelly <ian.g.kelly@gmail.com> - 2014-08-18 12:48 -0600
  Re: efficient partial sort in Python ? Dan Stromberg <drsalists@gmail.com> - 2014-08-18 14:42 -0700
    Re: efficient partial sort in Python ? Chiu Hsiang Hsu <wdv4758h@gmail.com> - 2014-08-19 12:37 -0700
      Re: efficient partial sort in Python ? Terry Reedy <tjreedy@udel.edu> - 2014-08-19 18:11 -0400
      Re: efficient partial sort in Python ? Dan Stromberg <drsalists@gmail.com> - 2014-08-19 16:05 -0700
      Re: efficient partial sort in Python ? Dan Stromberg <drsalists@gmail.com> - 2014-08-19 16:10 -0700
      Re: efficient partial sort in Python ? Dan Stromberg <drsalists@gmail.com> - 2014-08-19 16:22 -0700
      Re: efficient partial sort in Python ? Ian Kelly <ian.g.kelly@gmail.com> - 2014-08-19 18:00 -0600

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