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Re: Why generators take long time?

Path csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From Oscar Benjamin <oscar.j.benjamin@gmail.com>
Newsgroups comp.lang.python
Subject Re: Why generators take long time?
Date Tue, 19 Jan 2016 10:24:03 +0000
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On 19 Jan 2016 10:16, "Steven D'Aprano" <steve@pearwood.info> wrote:
>
> [steve@ando ~]$ python -m timeit -s "from collections import deque"
>     -s "it = iter([i for i in xrange(1000)])" "deque(it, maxlen=0)"
> 1000000 loops, best of 3: 0.913 usec per loop
>
>
> [steve@ando ~]$ python -m timeit -s "from collections import deque"
>     -s "it = (i for i in xrange(1000))" "deque(it, maxlen=0)"
> 1000000 loops, best of 3: 0.965 usec per loop

Surely the iterator in the above benchmarks is consumed during the first of
1000000 loops. Subsequent loops are just calling next on an exhausted
iterator.

--
Oscar

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Thread

Why generators take long time? Arshpreet Singh <arsh840@gmail.com> - 2016-01-18 23:27 -0800
  Re: Why generators take long time? Arshpreet Singh <arsh840@gmail.com> - 2016-01-19 00:06 -0800
  Re: Why generators take long time? Steven D'Aprano <steve@pearwood.info> - 2016-01-19 21:11 +1100
    Re: Why generators take long time? Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2016-01-19 10:24 +0000
      Re: Why generators take long time? Steven D'Aprano <steve@pearwood.info> - 2016-01-20 10:58 +1100
    Re: Why generators take long time? Arshpreet Singh <arsh840@gmail.com> - 2016-01-19 11:35 -0800
  Re: Why generators take long time? Jason Swails <jason.swails@gmail.com> - 2016-01-19 15:19 -0500
  Re: Why generators take long time? Jason Swails <jason.swails@gmail.com> - 2016-01-19 15:25 -0500

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