1 2 static char help[] = "Saves a dense matrix in a dense format (binary).\n\n"; 3 4 #include <petscmat.h> 5 6 int main(int argc,char **args) 7 { 8 Mat C; 9 PetscScalar v; 10 PetscInt i,j,m = 4,n = 4; 11 PetscMPIInt rank,size; 12 PetscViewer viewer; 13 14 PetscFunctionBeginUser; 15 PetscCall(PetscInitialize(&argc,&args,(char*)0,help)); 16 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank)); 17 PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size)); 18 PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL)); 19 PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL)); 20 21 /* PART 1: Generate matrix, then write it in binary format */ 22 23 /* Generate matrix */ 24 PetscCall(MatCreateSeqDense(PETSC_COMM_WORLD,m,n,NULL,&C)); 25 for (i=0; i<m; i++) { 26 for (j=0; j<n; j++) { 27 v = i*m+j; 28 PetscCall(MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES)); 29 } 30 } 31 PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY)); 32 PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY)); 33 PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,"matrix.dat",FILE_MODE_WRITE,&viewer)); 34 PetscCall(MatView(C,viewer)); 35 PetscCall(PetscViewerDestroy(&viewer)); 36 PetscCall(MatDestroy(&C)); 37 PetscCall(PetscFinalize()); 38 return 0; 39 } 40 41 /*TEST 42 43 test: 44 45 TEST*/ 46