[gmx-users] same simulation, different results

[David van der Spoel]

Jim Fonseca wrote:
> Shutting off the fft optimization produced the same results for 3.2.1.  
> Then I tried running two simulations using version 3.3.1 with the 
> optimized fft and they differed.  Your response seemed to imply that the 
> newer version should produce identical results.  Could you clear this up 
> for me?
> 
Turning on the fftw optimization may lead to different results in either 
version. Turning it off should give identical results.

-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assoc. Prof., Molecular Biophysics group,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://folding.bmc.uu.se
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