VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Wed Feb 23 2011 - 13:55:38 CST

Hi guys,
  I took a close look at this, and I think I've found what's going wrong
with the -masscenter case:
  double mscale = totalq / (totalm * sel->selected);

This is dividing by both total mass and by the number of selected
atoms, I believe it should only be dividing by total mass:
  double mscale = totalq / totalm;

This should account for the difference between the Tcl proc Stephane
wrote vs. the output from "measure dipole" with -masscenter.
I will double check this and commit the fix if I didn't miss something here.

Cheers,
  John

On Wed, Feb 23, 2011 at 05:30:36PM +0100, Stéphane Pezennec wrote:
> Le mercredi 23 février à 10h12 (-0500), Axel Kohlmeyer a écrit :
>
> > would you mind checking if this behavior still occurs in the latest
> > beta version of VMD?
>
> Thank you Axel for your reply. I just installed version 1.9beta1 and
> made a quick test: as you presumed, the 'measure dipole -masscenter'
> behave the same way as in version 1.8.7 and generates position-dependent
> dipole values.
>
> Regards,
>
> --
> Stephane 

-- 
NIH Resource for Macromolecular Modeling and Bioinformatics
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