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Date: Tue, 19 Aug 2014 16:22:48 -0700
Subject: Re: efficient partial sort in Python ?
From: Dan Stromberg <drsalists@gmail.com>
To: Chiu Hsiang Hsu <wdv4758h@gmail.com>
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On Tue, Aug 19, 2014 at 4:10 PM, Dan Stromberg <drsalists@gmail.com> wrote:
> On Tue, Aug 19, 2014 at 4:05 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.
>
> It just occurred to me that evicting the highest value each step of
> the way might be expensive with a traditional heap (since the value at
> the largest array index isn't necessarily the largest).  I've
> experimented with doing this using a treap a bit:
> http://stromberg.dnsalias.org/~strombrg/treap/  You might try that.

Or more directly relevant:
http://stromberg.dnsalias.org/~strombrg/highest/