I have two DMs which I add to a DMComposite and then use MATNEST when getting
the corresponding matrix. This gives me block (0,0) and block (1,1). How do I
set/get blocks (0,1) and (1,0)? Looking at ex28 I tried MatGetLocalSubMatrix
but it gives a null arg...
#include <petscdmda.h>
int main(int argc, char **argv)
{
DM da0, da1;
DMDABoundaryType bx = DMDA_BOUNDARY_PERIODIC, by = DMDA_BOUNDARY_PERIODIC;
DMDAStencilType stype = DMDA_STENCIL_STAR;
PetscInt Mx = 8, My = 8;
PetscInitialize(&argc, &argv, PETSC_NULL, PETSC_NULL);
// create distributed array for Q
DMDACreate2d(PETSC_COMM_WORLD,bx,by,stype,Mx,My,PETSC_DECIDE,PETSC_DECIDE,2,1,PETSC_NULL,PETSC_NULL,&da0);
// create distributed array for C
DMDACreate2d(PETSC_COMM_WORLD,bx,by,stype,Mx,My,PETSC_DECIDE,PETSC_DECIDE,1,1,PETSC_NULL,PETSC_NULL,&da1);
// mat nest from pack
DM pack;
Mat A;
Vec X;
DMCompositeCreate(PETSC_COMM_WORLD,&pack);
DMCompositeAddDM(pack,da0);
DMCompositeAddDM(pack,da1);
DMSetUp(pack);
DMGetMatrix(pack,MATNEST,&A);
MatView(A,PETSC_VIEWER_DEFAULT);
IS *is;
Mat G;
PetscInt col[1],ierr;
PetscScalar vals[1];
DMCompositeGetLocalISs(pack,&is);
MatGetLocalSubMatrix(A,is[0],is[1],&G);
MatView(G,PETSC_VIEWER_DEFAULT);
PetscFinalize();
return 0;
}
$ mpiexec -n 1 ./dmda-try3
Matrix object:
type=nest, rows=2, cols=2
MatNest structure:
(0,0) : type=seqaij, rows=128, cols=128
(0,1) : PETSC_NULL
(1,0) : PETSC_NULL
(1,1) : type=seqaij, rows=64, cols=64
[0]PETSC ERROR: --------------------- Error Message
------------------------------------
[0]PETSC ERROR: Null argument, when expecting valid pointer!
[0]PETSC ERROR: Null Object: Parameter # 1!
[0]PETSC ERROR:
------------------------------------------------------------------------
[0]PETSC ERROR: Petsc Release Version 3.2.0, Patch 5, Sat Oct 29 13:45:54 CDT
2011
[0]PETSC ERROR: See docs/changes/index.html for recent updates.
[0]PETSC ERROR: See docs/faq.html for hints about trouble shooting.
[0]PETSC ERROR: See docs/index.html for manual pages.
[0]PETSC ERROR:
------------------------------------------------------------------------
[0]PETSC ERROR: ./dmda-try3 on a linux_64b named lin0133 by cklaij Wed Jan 18
09:00:37 2012
[0]PETSC ERROR: Libraries linked from
/opt/refresco/64bit_intelv11.1_openmpi/petsc-3.2-p5/lib
[0]PETSC ERROR: Configure run at Mon Jan 16 14:03:34 2012
[0]PETSC ERROR: Configure options
--prefix=/opt/refresco/64bit_intelv11.1_openmpi/petsc-3.2-p5
--with-mpi-dir=/opt/refresco/64bit_intelv11.1_openmpi/openmpi-1.4.4 --with-x=0
--with-mpe=0 --with-debugging=1
--with-hypre-include=/opt/refresco/64bit_intelv11.1_openmpi/hypre-2.7.0b/include
--with-hypre-lib=/opt/refresco/64bit_intelv11.1_openmpi/hypre-2.7.0b/lib/libHYPRE.a
--with-ml-include=/opt/refresco/64bit_intelv11.1_openmpi/ml-6.2/include
--with-ml-lib=/opt/refresco/64bit_intelv11.1_openmpi/ml-6.2/lib/libml.a
--with-blas-lapack-dir=/opt/intel/mkl
[0]PETSC ERROR:
------------------------------------------------------------------------
[0]PETSC ERROR: MatView() line 723 in src/mat/interface/matrix.c
dr. ir. Christiaan Klaij
CFD Researcher
Research & Development
E mailto:C.Klaij at marin.nl
T +31 317 49 33 44
MARIN
2, Haagsteeg, P.O. Box 28, 6700 AA Wageningen, The Netherlands
T +31 317 49 39 11, F +31 317 49 32 45, I www.marin.nl
