[gmx-developers] floating points in src/gmxlib/nrnb.c

[Anton Feenstra]

David van der Spoel wrote:
> 
> On Tue, 14 May 2002, Mehmet Suezen wrote:
> 
> >Dear Gromacs Team,
> >
> >How one determine flops of innerloops as appeared in the routine nrnb.c?
> >  { "Bham",                      128 },
> >  { "Bham+ Coul",                270 },
> 
> go trhough the code and count...

But you should be aware that different operations weigh differently.
Addition, subtraction and multiplication are one flop, but division
and square-root are more expensive (I think we normally count them
for 10 flops, maybe you can confirm that from other parts of the code).

It wouldn't surprise me, however, if there was some automated way
of adding these annotations to the source code...?

-- 
Groetjes,

Anton
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|        | Anton Feenstra                                            |
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