#include "petscmat.h" PetscErrorCode MatCreateNest(MPI_Comm comm,PetscInt nr,const IS is_row[],PetscInt nc,const IS is_col[],const Mat a[],Mat *B)Collective on Mat
| comm | - Communicator for the new Mat | |
| nr | - number of nested row blocks | |
| is_row | - index sets for each nested row block, or NULL to make contiguous | |
| nc | - number of nested column blocks | |
| is_col | - index sets for each nested column block, or NULL to make contiguous | |
| a | - row-aligned array of nr*nc submatrices, empty submatrices can be passed using NULL |