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Re: NaN, Null, and Sorting

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From Robert Kern <robert.kern@gmail.com>
Subject Re: NaN, Null, and Sorting
Date Mon, 16 Jan 2012 11:07:26 +0000
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On 1/16/12 10:57 AM, Chris Angelico wrote:
> On Mon, Jan 16, 2012 at 9:22 PM, Eelco<hoogendoorn.eelco@gmail.com>  wrote:
>> What you want, conceptually, is a
>> sorted list of the sortable entries, and a seperate list of the
>> unsorted entries. Translated into code, the most pure solution would
>> be to filter out the nanas/nulls in their own list first, and then
>> sort the rest. If the interface demands it, you can concatenate the
>> lists afterwards, but probably it is most convenient to keep them in
>> seperate lists.
>
> So... you split it into two lists, sort the two lists (one of which
> can't be sorted), and then concatenate them. Sounds like the quicksort
> algorithm.

Not at all. The "split it into two lists" steps are entirely different in what 
Eelco suggested and quicksort. It's misleading to attempt to describe both using 
the same words.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco

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Thread

NaN, Null, and Sorting Ethan Furman <ethan@stoneleaf.us> - 2012-01-13 11:04 -0800
  Re: NaN, Null, and Sorting Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-01-14 04:54 +0000
  Re: NaN, Null, and Sorting jmfauth <wxjmfauth@gmail.com> - 2012-01-13 23:43 -0800
  Re: NaN, Null, and Sorting Eelco <hoogendoorn.eelco@gmail.com> - 2012-01-16 02:22 -0800
    Re: NaN, Null, and Sorting Chris Angelico <rosuav@gmail.com> - 2012-01-16 21:57 +1100
    Re: NaN, Null, and Sorting Robert Kern <robert.kern@gmail.com> - 2012-01-16 11:07 +0000

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