[petsc-users] diagonalizing dense matrix with LAPACK

[Barry Smith]

On Nov 7, 2012, at 12:46 PM, Jim Fonseca <jefonseca at gmail.com> wrote:

> Hi,
> Given a dense PETSc matrix, what is the most computationally efficient way to use LAPACK to diagonalize it?

   This seems to be a question about sequential matrix since LAPACK is sequential.

    Call MatGetArray() (MatDenseGetArray() in petsc-dev) and MatGetSizes() and pass the resulting info into the lapack routines (this will not involve a copy of the data).

   Barry

> 
> Thanks,
> Jim
> 
> -- 
> Jim Fonseca, PhD
> Research Scientist
> Network for Computational Nanotechnology
> Purdue University
> 765-496-6495
> www.jimfonseca.com
> 
> 
>