Re: Find in ipython3

From	Cecil Westerhof <Cecil@decebal.nl>
Newsgroups	comp.lang.python
Subject	Re: Find in ipython3
Organization	Decebal Computing
References	<87y4k2hyvf.fsf@Equus.decebal.nl> <mailman.177.1433448836.13271.python-list@python.org> <87bnguhbec.fsf@Equus.decebal.nl> <874mmlqhul.fsf@Equus.decebal.nl> <mailman.215.1433588892.13271.python-list@python.org>
Date	2015-06-07 08:20 +0200
Message-ID	<87sia4ox8h.fsf@Equus.decebal.nl> (permalink)

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On Saturday  6 Jun 2015 13:07 CEST, Laura Creighton wrote:

> The !find version is C code optimised to do one thing, find files in
> your directory structure, which happens to be what you want to do.
> General regular expression matching is harder.
>
> Carl Friedrich Bolz investigated regular expression algorithms and
> their implementation to see if this is the sort of task that a JIT
> can improve. He blogged about it in 2 posts (part1 and part2). There
> are benchmarks for part2. Benchmarks in part2.
>
> see:
> http://morepypy.blogspot.se/2010/05/efficient-and-elegant-regular.html
> http://morepypy.blogspot.se/2010/06/jit-for-regular-expression-matching.html
>
> You may get faster results if you use Matthew Barnett's replacement
> for re here: https://pypi.python.org/pypi/regex
>
> You will get faster results if you build your IPython shell to use
> PyPy, but I would still be very surprised if it beat the C program
> find.

I have to look into that. But I prefer to write a version that can be
used by ‘everyone’.

It is of-course not a very big program. The difference is significant,
but I do not use find that much. And if it is significant I still can
use the shell version.

There is no gain to get in standard Python? By switching from fnmatch
to re I got almost a speed gain of two. So I was wondering if I could
do more.

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof

Thread

Find in ipython3 Cecil Westerhof <Cecil@decebal.nl> - 2015-06-02 18:13 +0200
  Re: Find in ipython3 Cameron Simpson <cs@zip.com.au> - 2015-06-04 12:54 +1000
    Re: Find in ipython3 Cecil Westerhof <Cecil@decebal.nl> - 2015-06-04 07:09 +0200
      Re: Find in ipython3 Cameron Simpson <cs@zip.com.au> - 2015-06-04 15:43 +1000
      Re: Find in ipython3 Grant Edwards <invalid@invalid.invalid> - 2015-06-04 14:27 +0000
        Re: Find in ipython3 Cecil Westerhof <Cecil@decebal.nl> - 2015-06-04 17:12 +0200
          Re: Find in ipython3 Michael Torrie <torriem@gmail.com> - 2015-06-04 13:11 -0600
  Re: Find in ipython3 Michael Torrie <torriem@gmail.com> - 2015-06-04 13:09 -0600
  Re: Find in ipython3 Tim Chase <python.list@tim.thechases.com> - 2015-06-04 14:17 -0500
  Re: Find in ipython3 random832@fastmail.us - 2015-06-04 16:13 -0400
    Re: Find in ipython3 Cecil Westerhof <Cecil@decebal.nl> - 2015-06-05 09:17 +0200
      Re: Find in ipython3 Cecil Westerhof <Cecil@decebal.nl> - 2015-06-06 11:57 +0200
        Re: Find in ipython3 Laura Creighton <lac@openend.se> - 2015-06-06 13:07 +0200
          Re: Find in ipython3 Cecil Westerhof <Cecil@decebal.nl> - 2015-06-07 08:20 +0200
            Re: Find in ipython3 Cameron Simpson <cs@zip.com.au> - 2015-06-07 17:38 +1000
            Re: Find in ipython3 Laura Creighton <lac@openend.se> - 2015-06-07 11:33 +0200
              Re: Find in ipython3 Steven D'Aprano <steve@pearwood.info> - 2015-06-07 23:16 +1000
            Re: Find in ipython3 Peter Otten <__peter__@web.de> - 2015-06-07 12:27 +0200
            Re: Find in ipython3 Laura Creighton <lac@openend.se> - 2015-06-07 15:01 +0200
            Re: Find in ipython3 Chris Angelico <rosuav@gmail.com> - 2015-06-07 22:13 +1000

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