1 2 static char help[] = "Saves 4by4 block matrix.\n\n"; 3 4 #include <petscmat.h> 5 6 int main(int argc,char **args) 7 { 8 Mat A; 9 PetscInt i,j; 10 PetscErrorCode ierr; 11 PetscMPIInt size; 12 PetscViewer fd; 13 PetscScalar values[16],one = 1.0; 14 Vec x; 15 16 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 17 CHKERRMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size)); 18 PetscCheckFalse(size > 1,PETSC_COMM_WORLD,PETSC_ERR_WRONG_MPI_SIZE,m"Can only run on one processor"); 19 20 /* 21 Open binary file. Note that we use FILE_MODE_WRITE to indicate 22 writing to this file. 23 */ 24 CHKERRQ(PetscViewerBinaryOpen(PETSC_COMM_WORLD,"4by4",FILE_MODE_WRITE,&fd)); 25 26 CHKERRQ(MatCreateSeqBAIJ(PETSC_COMM_WORLD,4,12,12,0,0,&A)); 27 28 for (i=0; i<16; i++) values[i] = i; 29 for (i=0; i<4; i++) values[4*i+i] += 5; 30 i = 0; j = 0; 31 CHKERRQ(MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES)); 32 33 for (i=0; i<16; i++) values[i] = i; 34 i = 0; j = 2; 35 CHKERRQ(MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES)); 36 37 for (i=0; i<16; i++) values[i] = i; 38 i = 1; j = 0; 39 CHKERRQ(MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES)); 40 41 for (i=0; i<16; i++) values[i] = i;for (i=0; i<4; i++) values[4*i+i] += 6; 42 i = 1; j = 1; 43 CHKERRQ(MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES)); 44 45 for (i=0; i<16; i++) values[i] = i; 46 i = 2; j = 0; 47 CHKERRQ(MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES)); 48 49 for (i=0; i<16; i++) values[i] = i;for (i=0; i<4; i++) values[4*i+i] += 7; 50 i = 2; j = 2; 51 CHKERRQ(MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES)); 52 53 CHKERRQ(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY)); 54 CHKERRQ(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY)); 55 CHKERRQ(MatView(A,fd)); 56 CHKERRQ(MatDestroy(&A)); 57 58 CHKERRQ(VecCreateSeq(PETSC_COMM_WORLD,12,&x)); 59 CHKERRQ(VecSet(x,one)); 60 CHKERRQ(VecView(x,fd)); 61 CHKERRQ(VecDestroy(&x)); 62 63 CHKERRQ(PetscViewerDestroy(&fd)); 64 ierr = PetscFinalize(); 65 return ierr; 66 } 67