From: Axel Kohlmeyer (
Date: Fri Oct 16 2009 - 18:25:07 CDT

On Fri, 2009-10-16 at 19:48 -0300, Alberto Sergio Garay wrote:
> Hi all
> I am trying to run a tcl/tk script which uses pbctool2.5 but without
> graphic interface (vmd option -dispdev none or -dispdev text), but
> it warns me:
> invalid command name "pbc"
> So I think the problem is to load the pbctool at the moment of the
> script needs it. I have been looking for similar problem at the vmd
> list, but
> unfortunately I couldn' find any.

this is more of a tcl question.

you have to do: package require pbctools

and if you want at least version 2.5:
package require pbctools 2.5

you don't have to do this in the GUI version,
since there are other (GUI) plugins that require it.

for more details have a look at the documentation
of the tcl package command (e.g. "man n package").


> The script runs OK inside of the vmd graphical interface. I am using
> vmd 1.8.7 on a core 2 duo PC computer.
> Thank you in advance.

Dr. Axel Kohlmeyer 
Institute for Computational Molecular Science
College of Science and Technology
Temple University, Philadelphia PA, USA.