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Re: Speed Test for Comparison

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Bart said:

> You want to compare C code that does this *directly*, or C code that
> implements some arbitrary virtual machine that does the same job?
>
> In either case, the timings will be dominated by the time needed to 
> convert
> floating point numbers to strings, and, if the implementation does proper
> string handling, by the overheads of creating and discarding a million 
> short
> strings.
>
> Any comparison is anyway likely to be meaningless because you are testing
> one arbitrary implementation against another.
>
> FWIW, a simple sprintf() loop in C took about 1 second on my machine. Your 
> str(i/1000) loop in one of my scripting languages, with proper string 
> handling, took 2 seconds to execute a million times. This language is 
> usually much slower than C. So the actual task, rather than language 
> overheads, seems to be dominating execution time.
>
> However, given the complicated-looking C code that your language 
> generates, I'm surprised it isn't much slower. Your first step might be to 
> simply find out how long the task itself might be expected to take, but 
> I'm not sure why you can't do this for yourself:
>
> #include <stdio.h>
>
> int main(void) {
> int i;
> char str[100];
>
> for (i=0; i<1000000; ++i) {
> sprintf(str,"%f",i/1000.0);
> }
> }


Hi Bart:

    Thanks for the code:

    I'm going to use my MinGw 4.6.1 compiler and try to compile it and run 
it myself.

Thank you !

    (I need nothing more than this !)

and to Keith:  I don't expect anything more. Bart has provided what I wish.


-Mel Smith

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Thread

Speed Test for Comparison "Mel Smith" <med_cutout_syntel@aol.com> - 2011-12-08 10:09 -0700
  Re: Speed Test for Comparison Richard Sanders <lnr729@gmail.com> - 2011-12-08 11:19 -0800
    Re: Speed Test for Comparison "Mel Smith" <med_cutout_syntel@aol.com> - 2011-12-08 13:13 -0700
      Re: Speed Test for Comparison "Mel Smith" <med_cutout_syntel@aol.com> - 2011-12-08 13:18 -0700
        Re: Speed Test for Comparison Seebs <usenet-nospam@seebs.net> - 2011-12-08 20:41 +0000
          Re: Speed Test for Comparison Ben Pfaff <blp@cs.stanford.edu> - 2011-12-08 12:49 -0800
            Re: Speed Test for Comparison Seebs <usenet-nospam@seebs.net> - 2011-12-08 21:53 +0000
      Re: Speed Test for Comparison Seebs <usenet-nospam@seebs.net> - 2011-12-08 20:41 +0000
  Re: Speed Test for Comparison "BartC" <bc@freeuk.com> - 2011-12-08 21:43 +0000
  Re: Speed Test for Comparison ImpalerCore <jadill33@gmail.com> - 2011-12-08 13:58 -0800
  Re: Speed Test for Comparison Keith Thompson <kst-u@mib.org> - 2011-12-08 14:58 -0800
    Re: Speed Test for Comparison "Mel Smith" <med_cutout_syntel@aol.com> - 2011-12-10 11:28 -0700
      Re: Speed Test for Comparison "BartC" <bc@freeuk.com> - 2011-12-10 21:40 +0000
        Re: Speed Test for Comparison "Mel Smith" <med_cutout_syntel@aol.com> - 2011-12-10 19:26 -0700
      Re: Speed Test for Comparison Keith Thompson <kst-u@mib.org> - 2011-12-10 13:49 -0800

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