VMD-L Mailing List

From: Neelanjana Sengupta (senguptan_at_gmail.com)
Date: Tue Sep 05 2006 - 18:26:31 CDT

Hi,

Thanks for all the input. However, I found that what Jan recommended works.
I found the inverse of my matrix with
set matInv [measure inverse $matrix]

transmult $matrix $matInv does give me the identity matrix.

~Neela

On 9/5/06, Axel Kohlmeyer <akohlmey_at_cmm.chem.upenn.edu> wrote:
>
> hi,
>
> a generic matrix inversion is not available.
> to undo many transformation matrices, you
> may get away with a transpose+rescale (it
> has been a looong time since i needed to
> deal with it seriously).
>
> but you are in the market for real inversion, you
> may want to have a look at:
> http://www.hume.com/la/
> if your code is not performance critical.
>
> other than that, the next best option would be
> to implement a wrapper plugin for BLAS/LAPACK...
> i've been thinking about this for a while,
> but there was rarely enough contigouus time
> (and if there was, there were more pressing projects)
> to try something like that in a serious manner.
>
> cheers,
> axel.
>
> On 9/5/06, Neelanjana Sengupta <senguptan_at_gmail.com> wrote:
> > Hi,
> > Does VMD have a routine to find the inverse of a matrix? I am referring
> to
> > the 'trans' matrix operations, used to perform a variety pf coordianate
> > transformations:
> > http://www.ks.uiuc.edu/Research/vmd/current/ug/node176.html
> >
> > I did not see anything like "transinverse"...
> >
> > Thanks and regards,
> > Neela
> >
>
>
> --
> =======================================================================
> Axel Kohlmeyer akohlmey_at_cmm.chem.upenn.edu http://www.cmm.upenn.edu
> Center for Molecular Modeling -- University of Pennsylvania
> Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323
> tel: 1-215-898-1582, fax: 1-215-573-6233, office-tel: 1-215-898-5425
> =======================================================================
> If you make something idiot-proof, the universe creates a better idiot.
>