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Re: how to convert code that uses cmp to python3

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From Chris Angelico <rosuav@gmail.com>
Newsgroups comp.lang.python
Subject Re: how to convert code that uses cmp to python3
Date Sat, 9 Apr 2016 00:08:38 +1000
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On Fri, Apr 8, 2016 at 11:31 PM, Antoon Pardon
<antoon.pardon@rece.vub.ac.be> wrote:
> Doing it as follows:
>     seq1 < seq2
>     seq2 < seq1
>
> takes about 110 seconds.
>
>
> Doing it like this:
>     delta = cmp(seq1, seq2)
>     delta < 0
>     delta > 0
>
> takes about 50 seconds.

Why are you comparing in both directions, though? cmp() is more
equivalent to this:

seq1 == seq2
seq1 < seq2

You only need ONE comparison, and the other is presumed to be its
opposite. When, in the Python 3 version, would you need to compare
twice?

ChrisA

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Re: how to convert code that uses cmp to python3 Chris Angelico <rosuav@gmail.com> - 2016-04-09 00:08 +1000

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