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References: <87h9rvm576.fsf@Equus.decebal.nl> <871tixlmp6.fsf@Equus.decebal.nl> <750db03b-e393-43ff-9ccf-5cc050af7324@googlegroups.com> <87zj5jf15q.fsf@Equus.decebal.nl> <55490FAE.8070501@davea.name> <CALwzidmuhD0HhAZKRGMbgEgVVHf05_3pw=+o2JyAwWdiOtcNNA@mail.gmail.com> <55492F55.1020105@davea.name>
From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Tue, 5 May 2015 15:23:58 -0600
Subject: Re: Throw the cat among the pigeons
To: Python <python-list@python.org>
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On Tue, May 5, 2015 at 3:00 PM, Dave Angel <davea@davea.name> wrote:
> def loop(func, funcname, arg):
>     start = time.time()
>     for i in range(repeats):
>         func(arg, True)
>     print("{0}({1}) took {2:7.4}".format(funcname, arg, time.time()-start))
>
>     start = time.time()
>     for i in range(repeats):
>         func(arg)
>     print("{0}({1}) took {2:7.4}".format(funcname, arg, time.time()-start))

Note that you're explicitly passing True in one case but leaving the
default in the other. I don't know whether that might be responsible
for the difference you're seeing.

Also, it's best to use the timeit module for timing code, e.g.:

>>> from timeit import Timer
>>> t1 = Timer("factorial_iterative(100000, False)", "from __main__ import factorial_iterative")
>>> t1.repeat(10, number=1)
[3.8517245299881324, 3.7571076710009947, 3.7780062559759244,
3.848508063936606, 3.7627131739864126, 3.8278848479967564,
3.776115525048226, 3.83024005102925, 3.8322679550619796,
3.8195601429324597]
>>> min(_), sum(_) / len(_)
(3.7571076710009947, 3.8084128216956743)
>>> t2 = Timer("factorial_iterative(100000, True)", "from __main__ import factorial_iterative")
>>> t2.repeat(10, number=1)
[3.8363616950809956, 3.753201302024536, 3.7838632150087506,
3.7670978900277987, 3.805312803015113, 3.7682680500438437,
3.856655619922094, 3.796431727008894, 3.8224815409630537,
3.765664782957174]
>>> min(_), sum(_) / len(_)
(3.753201302024536, 3.7955338626052253)

As you can see, in my testing the True case was actually marginally
(probably not significantly) faster in both the min and the average.