From: John Stone (
Date: Fri Sep 28 2007 - 16:25:34 CDT

  At present there is only a single per-timestep "user" field, but
it is actually pretty easy to create new user-defined fields. I have
been planning on making it possible to create and define new
per-timestep user-defined fields on-the-fly but haven't gotten around
to doing it yet. Creating and naming new fields is trivial, I just
have to come up with a clean way to add/delete dynamically created field
names into the atom selection language.

If you like, I can tell you how to make a few of small changes to
the VMD source to add as many new per-timestep fields as you want.
You'd have to compile from source, but that's the easiest way to get
it done until I've implemented a more general solution.

  John Stone

On Fri, Sep 28, 2007 at 05:15:05PM -0400, Bob Johnson wrote:
> Hello everyone,
> I would like to store the values of multiple time varying variables in the user
> field. For example, I would like to store the RMSD values between each frame
> and two (or maybe more) reference structures. Ideally, it would be great if the
> user field per frame were an array that could store multiple values and be
> accessed via something like: $sel get user(i) Here i is the index of each value
> stored in the array. Is there a way to do this?
> Thanks,
> Bob

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