inverting independent, small dense matrices

[Matthew Knepley]

I think the easiest thing to do is use a BAIJ matrix with blocksize 4 to
store
all the matrices. Then factorization will handle LAPACK for you.

  Matt

On Fri, Feb 13, 2009 at 3:01 PM, Shao-Ching Huang <schuang at ats.ucla.edu>wrote:

> Hi
>
> I need to invert a bunch of independent, dense 4x4 matrices on each
> MPI process. (This is separate from the main computation, a parallel
> Ax=b solve.) I am thinking of using LAPACK's DGESV to invert these 4x4
> matrices.
>
> In my code, is it necessary to call LAPACK directly? Or does PETSc
> already have a convenient interface to LAPACK?
>
> The size 4x4 may be increased to 8x8 or so later, so I am not trying
> to use the closed-form inversion formula.
>
> Thanks,
>
> Shao-Ching
>



-- 
What most experimenters take for granted before they begin their experiments
is infinitely more interesting than any results to which their experiments
lead.
-- Norbert Wiener
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20090213/245b90e8/attachment.htm>