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Re: Dict comprehensions - improvement to docs?

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From Ian Kelly <ian.g.kelly@gmail.com>
Date Tue, 17 Mar 2015 09:48:14 -0600
Subject Re: Dict comprehensions - improvement to docs?
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On Tue, Mar 17, 2015 at 12:44 AM, Frank Millman <frank@chagford.com> wrote:
> Thanks for the explanation. I'll try not to make that mistake again.
>
> However, to go back to the original example, we want to compare a dict
> comprehension with a dict() constructor using a generator expression.
>
> Let's see if I have got this one right -
>
> C:\>python -m timeit -s "x=range(65, 91); y=[chr(z) for z in x]" "dict((a,
> b) for a, b in zip(x, y))"
> 10000 loops, best of 3: 49.6 usec per loop
>
> C:\>python -m timeit -s "x=range(65, 91); y=[chr(z) for z in x]" "{a: b for
> a, b in zip(x, y)}"
> 10000 loops, best of 3: 25.8 usec per loop

Why did you revert back to the no-op generator expression in the first
case instead of the more efficient dict(zip(x, y))?

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Thread

Dict comprehensions - improvement to docs? "Frank Millman" <frank@chagford.com> - 2015-03-16 07:25 +0200
  Re: Dict comprehensions - improvement to docs? Paul Rubin <no.email@nospam.invalid> - 2015-03-15 23:22 -0700
    Re: Dict comprehensions - improvement to docs? "Frank Millman" <frank@chagford.com> - 2015-03-16 10:30 +0200
      Re: Dict comprehensions - improvement to docs? Paul Rubin <no.email@nospam.invalid> - 2015-03-16 01:38 -0700
        Re: Dict comprehensions - improvement to docs? "Frank Millman" <frank@chagford.com> - 2015-03-16 11:01 +0200
        Re: Dict comprehensions - improvement to docs? Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-16 09:57 -0600
          Re: Dict comprehensions - improvement to docs? Paul Rubin <no.email@nospam.invalid> - 2015-03-16 15:41 -0700
        Re: Dict comprehensions - improvement to docs? "Frank Millman" <frank@chagford.com> - 2015-03-17 08:44 +0200
        Re: Dict comprehensions - improvement to docs? Lele Gaifax <lele@metapensiero.it> - 2015-03-17 15:06 +0100
        Re: Dict comprehensions - improvement to docs? Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-17 09:48 -0600
        Re: Dict comprehensions - improvement to docs? "Frank Millman" <frank@chagford.com> - 2015-03-18 10:01 +0200
        Re: Dict comprehensions - improvement to docs? Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-18 02:39 -0600

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