[gmx-users] General questions

[K.A.Feenstra]

David van der Spoel wrote:
> 
> On Fri, 14 Dec 2001, Marc Baaden wrote:
> 
> >
> >Here some things under the topic "What I often wondered about,
> >but never actually asked anybody" ...
> >
> >- is there a way of estimating the size of XTC and TRR, .. files ?
> >  given that number of atoms and frequency of writing is known or
> >  can be retrieved from the mdp file
> 
> trr = 12*natoms*(nsteps/nstxout+nsteps/nstvout+nsteps/nstfout)
> xtc = 4*natoms*nsteps/nstxout

Is exact for trr, and approximate for xtc (since xtc is compressed).

> >- is there an easy way of calculating the closest distance in any
> >   of the 3 directions x,y and z of a molecule to its periodic
> >   images when using pbc
> 
> No, but it would be useful.

Actually, there is: 'g_mindist -pi' will do that for you.

-- 
Groetjes,

Anton
 _____________ _____________________________________________________
|             | Anton Feenstra       Dept. of Biophysical Chemistry |
|  _   _  ___,| K.A.Feenstra at chem.rug.nl    University of Groningen |
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