From: Axel Kohlmeyer (
Date: Thu Oct 03 2013 - 11:37:49 CDT

On Thu, Oct 3, 2013 at 5:40 PM, Peterson J <> wrote:
> Hello VMD Users,
> I am trying to calculate the angle between two domains of my protein. I have
> calculated the inertia for both domains which provided me the center of mass
> and the principal axes of each domain. But I have a problem calculating the
> angle using the two principal axes. The 'measure angle' asks for three atom
> indices.
> How do I measure it?

how do you compute the angle between two vectors?


> Thanks
> Peter

Dr. Axel Kohlmeyer
International Centre for Theoretical Physics, Trieste. Italy.