#include "petscmat.h" PetscErrorCode MatMPIAIJGetSeqAIJ(Mat A,Mat *Ad,Mat *Ao,const PetscInt *colmap[])Not collective
| A | - The MPIAIJ matrix |
| Ad | - The local diagonal block as a SeqAIJ matrix | |
| Ao | - The local off-diagonal block as a SeqAIJ matrix | |
| colmap | - An array mapping local column numbers of Ao to global column numbers of the parallel matrix |
Note: The rows in Ad and Ao are in [0, Nr), where Nr is the number of local rows on this process. The columns in Ad are in [0, Nc) where Nc is the number of local columns. The columns are Ao are in [0, Nco), where Nco is the number of nonzero columns in the local off-diagonal piece of the matrix A. The array colmap maps these local column numbers to global column numbers in the original matrix.