1c4762a1bSJed Brown 2c4762a1bSJed Brown static char help[] = "Tests MatCreateSubmatrix() with certain entire rows of matrix, modified from ex181.c."; 3c4762a1bSJed Brown 4c4762a1bSJed Brown #include <petscmat.h> 5c4762a1bSJed Brown 6c4762a1bSJed Brown int main(int argc,char **args) 7c4762a1bSJed Brown { 8c4762a1bSJed Brown Mat C,A; 9c4762a1bSJed Brown PetscInt i,j,m = 3,n = 2,rstart,rend,cstart,cend; 10c4762a1bSJed Brown PetscMPIInt size,rank; 11c4762a1bSJed Brown PetscScalar v; 12c4762a1bSJed Brown IS isrow,iscol; 13c4762a1bSJed Brown 14*9566063dSJacob Faibussowitsch PetscCall(PetscInitialize(&argc,&args,(char*)0,help)); 15*9566063dSJacob Faibussowitsch PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank)); 16*9566063dSJacob Faibussowitsch PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size)); 17c4762a1bSJed Brown n = 2*size; 18c4762a1bSJed Brown 19*9566063dSJacob Faibussowitsch PetscCall(MatCreate(PETSC_COMM_WORLD,&C)); 20*9566063dSJacob Faibussowitsch PetscCall(MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n)); 21*9566063dSJacob Faibussowitsch PetscCall(MatSetFromOptions(C)); 22*9566063dSJacob Faibussowitsch PetscCall(MatSetUp(C)); 23c4762a1bSJed Brown 24c4762a1bSJed Brown /* 25c4762a1bSJed Brown This is JUST to generate a nice test matrix, all processors fill up 26c4762a1bSJed Brown the entire matrix. This is not something one would ever do in practice. 27c4762a1bSJed Brown */ 28*9566063dSJacob Faibussowitsch PetscCall(MatGetOwnershipRange(C,&rstart,&rend)); 29c4762a1bSJed Brown for (i=rstart; i<rend; i++) { 30c4762a1bSJed Brown for (j=0; j<m*n; j++) { 31c4762a1bSJed Brown v = i + j + 1; 32*9566063dSJacob Faibussowitsch PetscCall(MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES)); 33c4762a1bSJed Brown } 34c4762a1bSJed Brown } 35*9566063dSJacob Faibussowitsch PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY)); 36*9566063dSJacob Faibussowitsch PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY)); 37*9566063dSJacob Faibussowitsch PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_COMMON)); 38*9566063dSJacob Faibussowitsch PetscCall(MatView(C,PETSC_VIEWER_STDOUT_WORLD)); 39*9566063dSJacob Faibussowitsch PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD)); 40c4762a1bSJed Brown 41c4762a1bSJed Brown /* 42c4762a1bSJed Brown Generate a new matrix consisting every column of the original matrix 43c4762a1bSJed Brown */ 44*9566063dSJacob Faibussowitsch PetscCall(MatGetOwnershipRange(C,&rstart,&rend)); 45*9566063dSJacob Faibussowitsch PetscCall(MatGetOwnershipRangeColumn(C,&cstart,&cend)); 46c4762a1bSJed Brown 47*9566063dSJacob Faibussowitsch PetscCall(ISCreateStride(PETSC_COMM_WORLD,rend-rstart > 0 ? rend-rstart-1 : 0,rstart,1,&isrow)); 48*9566063dSJacob Faibussowitsch PetscCall(ISCreateStride(PETSC_COMM_WORLD,cend-cstart,cstart,1,&iscol)); 49*9566063dSJacob Faibussowitsch PetscCall(MatCreateSubMatrix(C,isrow,NULL,MAT_INITIAL_MATRIX,&A)); 50c4762a1bSJed Brown 51c4762a1bSJed Brown /* Change C to test the case MAT_REUSE_MATRIX */ 52dd400576SPatrick Sanan if (rank == 0) { 53c4762a1bSJed Brown i = 0; j = 0; v = 100; 54*9566063dSJacob Faibussowitsch PetscCall(MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES)); 55c4762a1bSJed Brown } 56*9566063dSJacob Faibussowitsch PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY)); 57*9566063dSJacob Faibussowitsch PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY)); 58c4762a1bSJed Brown 59*9566063dSJacob Faibussowitsch PetscCall(MatCreateSubMatrix(C,isrow,NULL,MAT_REUSE_MATRIX,&A)); 60*9566063dSJacob Faibussowitsch PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_COMMON)); 61*9566063dSJacob Faibussowitsch PetscCall(MatView(A,PETSC_VIEWER_STDOUT_WORLD)); 62*9566063dSJacob Faibussowitsch PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD)); 63c4762a1bSJed Brown 64*9566063dSJacob Faibussowitsch PetscCall(ISDestroy(&isrow)); 65*9566063dSJacob Faibussowitsch PetscCall(ISDestroy(&iscol)); 66*9566063dSJacob Faibussowitsch PetscCall(MatDestroy(&A)); 67*9566063dSJacob Faibussowitsch PetscCall(MatDestroy(&C)); 68*9566063dSJacob Faibussowitsch PetscCall(PetscFinalize()); 69b122ec5aSJacob Faibussowitsch return 0; 70c4762a1bSJed Brown } 71c4762a1bSJed Brown 72c4762a1bSJed Brown /*TEST 73c4762a1bSJed Brown 74c4762a1bSJed Brown test: 75c4762a1bSJed Brown nsize: 2 76c4762a1bSJed Brown 77c4762a1bSJed Brown TEST*/ 78