[gmx-users] timestep

[Rainer Boeckmann]

David van der Spoel wrote:

> On Mon, 25 Mar 2002, Mehmet Suezen wrote:
>
> >Rainer Boeckmann wrote:
> >>
> >> ...and what about the energy? Restarting with a different timestep yields a
> >> different kinetic energy! That was the question...
> >> rainer
> >
> >then,..How would you determine suitable time step?
> If you change the timestep, you'll get a discontinuity in the trajectory,
> and in the energies.
>

that's ok.

> But you were referring to different timestep giving different temperature
> right? Please check that other parameters (expressed in timesteps) keep
> their same value in fs, in particular nstlist (neighbourlist update).
>
> Maybe we should change these variables to time instead of steps...
>
> Groeten, David.
> ________________________________________________________________________
> Dr. David van der Spoel,        Biomedical center, Dept. of Biochemistry
> Husargatan 3, Box 576,          75123 Uppsala, Sweden
> phone:  46 18 471 4205          fax: 46 18 511 755
> spoel at xray.bmc.uu.se    spoel at gromacs.org  http://zorn.bmc.uu.se/~spoel
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>

maybe that's the problem. I did in fact only change the timestep. But: how do
parameters like nstlist affect the energies at step 0? The kinetic energy at step
0 is different fot two runs starting from the same gro-file but with different
delta t. Thought these parameters were only important for later steps...
Thanks a lot,

Rainer