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Re: Bitshifts and "And" vs Floor-division and Modular

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From Grant Edwards <invalid@invalid.invalid>
Newsgroups comp.lang.python
Subject Re: Bitshifts and "And" vs Floor-division and Modular
Date Fri, 7 Sep 2012 14:19:07 +0000 (UTC)
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On 2012-09-07, Steven D'Aprano <steve+comp.lang.python@pearwood.info> wrote:

> My *guess* is that you mean *bitwise* operators, compared to numeric 
> operators like * and // (integer division). The runtime cost is mostly 
> dominated by the object-oriented overhead -- Python is not C or assembly,
> and the integers are rich objects, not low-level bitfields, so the 
> difference between division and bitshifting is much less than you might 
> expect from assembly language.

I don't suppose there's much of a chance that the OP is running Python
on a CPU that doesn't have an integer divide instruction?  If that
_were_ the case, the difference would be more noticable, but would
still probably not worth worrying about unless a truely huge number of
operations were being done in a very tight loop with no intervening
I/O operations.

-- 
Grant Edwards               grant.b.edwards        Yow! I have accepted
                                  at               Provolone into my life!
                              gmail.com            

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Thread

Bitshifts and "And" vs Floor-division and Modular jimbo1qaz <jimmyli1528@gmail.com> - 2012-09-06 17:01 -0700
  Re: Bitshifts and "And" vs Floor-division and Modular Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-09-07 01:30 +0100
    Re: Bitshifts and "And" vs Floor-division and Modular jimbo1qaz <jimmyli1528@gmail.com> - 2012-09-06 18:05 -0700
    Re: Bitshifts and "And" vs Floor-division and Modular jimbo1qaz <jimmyli1528@gmail.com> - 2012-09-06 18:05 -0700
  Re: Bitshifts and "And" vs Floor-division and Modular jimbo1qaz <jimmyli1528@gmail.com> - 2012-09-06 18:30 -0700
    Re: Bitshifts and "And" vs Floor-division and Modular Dave Angel <d@davea.name> - 2012-09-06 21:46 -0400
    Re: Bitshifts and "And" vs Floor-division and Modular Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-07 02:23 +0000
  Re: Bitshifts and "And" vs Floor-division and Modular Dave Angel <d@davea.name> - 2012-09-06 21:36 -0400
  Re: Bitshifts and "And" vs Floor-division and Modular Terry Reedy <tjreedy@udel.edu> - 2012-09-06 21:53 -0400
  Re: Bitshifts and "And" vs Floor-division and Modular Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-09-07 02:00 +0000
    Re: Bitshifts and "And" vs Floor-division and Modular Grant Edwards <invalid@invalid.invalid> - 2012-09-07 14:19 +0000
  Re: Bitshifts and "And" vs Floor-division and Modular rusi <rustompmody@gmail.com> - 2012-09-06 20:38 -0700
    Re: Bitshifts and "And" vs Floor-division and Modular Paul Rubin <no.email@nospam.invalid> - 2012-09-06 21:32 -0700
      Re: Bitshifts and "And" vs Floor-division and Modular rusi <rustompmody@gmail.com> - 2012-09-07 09:59 -0700
        Re: Bitshifts and "And" vs Floor-division and Modular Dave Angel <d@davea.name> - 2012-09-07 13:12 -0400

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