Actual source code: ex43.c
2: static char help[] = "Saves a dense matrix in a dense format (binary).\n\n";
4: #include <petscmat.h>
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;
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));
21: /* PART 1: Generate matrix, then write it in binary format */
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: }
41: /*TEST
43: test:
45: TEST*/