[gmx-users] weird nst*out problem

[Anton Feenstra]

David wrote:
> 
> On Wed, 2003-01-08 at 17:06, Bert de Groot wrote:
> >> However, this is not the case (output from a tool that simply reads
> > the times from a .xtc file, which is btw also what tools like g_rms
> > etc report as times in the .xvg files for example):
> >
> >    300000.00000
> >    300000.09375
> >    300000.18750
> >    300000.31250
> >    300000.40625
> >    300000.50000
[...]

But these also don't look like numbers you can get using a .002 ps
timestep (2 fs) and an irregular nstxout effect (you'd get multiples
of .002 ps, obviously).

> I think Anton is correct in assuming the right frames are stored, but
> the precision of the float used for time is not more than 7 digits. You
> therefore get these rounding problems.

I also have a hard time imagining why you'd want to store (and analyse) 
details on a .1 ps timescale from a 300 ns simulation...!?

-- 
Groetjes,

Anton
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