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Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1")

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From Terry Reedy <tjreedy@udel.edu>
Subject Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1")
Date Sun, 21 Aug 2011 22:15:07 -0400
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On 8/21/2011 7:49 PM, Laurent Payot wrote:
> I made Python my language of choice because of its readability and
> simpleness, and not because of its speed. But it's always good to
> know what is the fastest sometimes when you don't want to write a
> module in C. So I was just wondering if there was a difference. There
> is, of a few percent. Anyway I will keep on using the 2% slower "i +=
> 1" because for me that's less prone to errors because you write the
> variable only once, and that's more important than speed.

For longer variable names, it is also easier and faster to read once one 
gets used to the idiom.

number_of_chars += 1 # versus
number_of_chars = number_of_chars + 1

Not repeating was a major reason for the addition.

-- 
Terry Jan Reedy

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Thread

relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Laurent <laurent.payot@gmail.com> - 2011-08-21 09:52 -0700
  Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") woooee <woooee@gmail.com> - 2011-08-21 09:59 -0700
    Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Laurent <laurent.payot@gmail.com> - 2011-08-21 10:03 -0700
      Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Irmen de Jong <irmen@-NOSPAM-xs4all.nl> - 2011-08-21 19:14 +0200
        Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Hans Mulder <hansmu@xs4all.nl> - 2011-08-21 19:57 +0200
  Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Nobody <nobody@nowhere.com> - 2011-08-21 22:07 +0100
    Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Laurent Payot <laurent.payot@gmail.com> - 2011-08-21 16:49 -0700
      Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Terry Reedy <tjreedy@udel.edu> - 2011-08-21 22:15 -0400
    Re: relative speed of incremention syntaxes (or "i=i+1" VS "i+=1") Terry Reedy <tjreedy@udel.edu> - 2011-08-21 20:35 -0400

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