From: John Stone (
Date: Thu Jan 28 2016 - 21:57:04 CST

  At present the VMD Gromacs plugin doesn't read velocities, but if you have
some sample files we could use for testing, it might only require a minor
change to add this capability. When the code was originally written, the
versions of VMD at that time didn't support velocities, but the current
versions do.

  John Stone

On Thu, Jan 28, 2016 at 05:30:47PM +0100, Davide Mercadante wrote:
> Dear All,
> I have been reading several posts about this but I couldn???t find an answer and what I am trying is not working. I have a simulation run with GROMACS and trr or eventually gro files in which velocity information for each atom are stored. In order to do something with those in my script I want to extract these information.
> I???ve found this which makes me think that may be there is no easy solution yet for this inside vmd. The "$sel get {vx vy vz}" command doesn???t seem to be working as I get a list with 0 values {0.0 0.0 0.0}. Looking at previous posts on the mailing list some other users successfully ran this command to get velocities out but I am not sure if they were using NAMD- or LAMMPS-like trajectories (not specified). Is there any other way of getting these information using VMD and gromacs trajectories?
> Thank you for your time.
> Cheers,
> Davide

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