efficient partial sort in Python ?

Newsgroups	comp.lang.python
Date	2014-08-18 10:18 -0700
Message-ID	<51dfbe9b-f6e0-4532-bc2d-e7ce2fc282b5@googlegroups.com> (permalink)
Subject	efficient partial sort in Python ?
From	Chiu Hsiang Hsu <wdv4758h@gmail.com>

Show all headers | View raw

I know that Python use Timsort as default sorting algorithm and it is efficient,
but I just wanna have a partial sorting (n-largest/smallest elements).

In the current state, I can only find this kind of functions from heapq,
but it's too slow for this problem,
the pure c sorted function can easily beat heapq.nlargest even though it sort all the elements.

I think it would be better if we have an effeicient partial sorting function,
maybe it could be like this : partial_sorted(data, n), data.partial_sort(n)

Does anyone have any more information for partial sorting ?

Btw, C++ has a partial_sort function in <algorithm>, but I don't know what algorithm it really use.

Back to comp.lang.python | Previous | Next — Next in thread | Find similar | Unroll thread

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

csiph-web