[gmx-users] editing velocities in tprs

[Berk Hess]

>From: "Alex Robertson" <alexrson at stanford.edu>
>Reply-To: Discussion list for GROMACS users <gmx-users at gromacs.org>
>To: "Discussion list for GROMACS users" <gmx-users at gromacs.org>
>Subject: [gmx-users] editing velocities in tprs
>Date: Tue, 5 Jul 2005 15:00:46 -0700
>
>Hi
>    I am trying to take some tprs that I have created and create new one's 
>with all the velocities inverted.  Does anyone know how to edit the 
>information in tprs?  Or how to take the output from gmsdump and turn that 
>into a run input file?

I guess the easiest thing is editing grompp to reverse the velocities.

But why do you want to do this?
If it is for reversibility test of the leap-frog integrator
you also have to take the velocities of the next step,
as the velocitities are stored at half steps.

Berk.