petsc-3.11.4 2019-09-28
MatGetMultiProcBlock
Create multiple [bjacobi] 'parallel submatrices' from a given 'mat' object. Each submatrix can span multiple procs.
Synopsis
#include "petscmat.h"
PetscErrorCode MatGetMultiProcBlock(Mat mat, MPI_Comm subComm, MatReuse scall,Mat *subMat)
Collective on Mat
Input Parameters
Output Parameter
subMat -'parallel submatrices each spans a given subcomm
Notes
The submatrix partition across processors is dictated by 'subComm' a
communicator obtained by com_split(comm). The comm_split
is not restriced to be grouped with consecutive original ranks.
Due the comm_split() usage, the parallel layout of the submatrices
map directly to the layout of the original matrix [wrt the local
row,col partitioning]. So the original 'DiagonalMat' naturally maps
into the 'DiagonalMat' of the subMat, hence it is used directly from
the subMat. However the offDiagMat looses some columns - and this is
reconstructed with MatSetValues()
See Also
MatCreateSubMatrices()
Level
advanced
Location
src/mat/interface/matrix.c
Implementations
MatGetMultiProcBlock_MPIAIJ in src/mat/impls/aij/mpi/mpb_aij.c
MatGetMultiProcBlock_SeqAIJ in src/mat/impls/aij/seq/aij.c
MatGetMultiProcBlock_MPIBAIJ in src/mat/impls/baij/mpi/mpb_baij.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages