Actual source code: ex64.c
2: static char help[] = "Saves 4by4 block matrix.\n\n";
4: #include <petscmat.h>
6: int main(int argc, char **args)
7: {
8: Mat A;
9: PetscInt i, j;
10: PetscMPIInt size;
11: PetscViewer fd;
12: PetscScalar values[16], one = 1.0;
13: Vec x;
16: PetscInitialize(&argc, &args, (char *)0, help);
17: MPI_Comm_size(PETSC_COMM_WORLD, &size);
20: /*
21: Open binary file. Note that we use FILE_MODE_WRITE to indicate
22: writing to this file.
23: */
24: PetscViewerBinaryOpen(PETSC_COMM_WORLD, "4by4", FILE_MODE_WRITE, &fd);
26: MatCreateSeqBAIJ(PETSC_COMM_WORLD, 4, 12, 12, 0, 0, &A);
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;
31: j = 0;
32: MatSetValuesBlocked(A, 1, &i, 1, &j, values, INSERT_VALUES);
34: for (i = 0; i < 16; i++) values[i] = i;
35: i = 0;
36: j = 2;
37: MatSetValuesBlocked(A, 1, &i, 1, &j, values, INSERT_VALUES);
39: for (i = 0; i < 16; i++) values[i] = i;
40: i = 1;
41: j = 0;
42: MatSetValuesBlocked(A, 1, &i, 1, &j, values, INSERT_VALUES);
44: for (i = 0; i < 16; i++) values[i] = i;
45: for (i = 0; i < 4; i++) values[4 * i + i] += 6;
46: i = 1;
47: j = 1;
48: MatSetValuesBlocked(A, 1, &i, 1, &j, values, INSERT_VALUES);
50: for (i = 0; i < 16; i++) values[i] = i;
51: i = 2;
52: j = 0;
53: MatSetValuesBlocked(A, 1, &i, 1, &j, values, INSERT_VALUES);
55: for (i = 0; i < 16; i++) values[i] = i;
56: for (i = 0; i < 4; i++) values[4 * i + i] += 7;
57: i = 2;
58: j = 2;
59: MatSetValuesBlocked(A, 1, &i, 1, &j, values, INSERT_VALUES);
61: MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);
62: MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);
63: MatView(A, fd);
64: MatDestroy(&A);
66: VecCreateSeq(PETSC_COMM_WORLD, 12, &x);
67: VecSet(x, one);
68: VecView(x, fd);
69: VecDestroy(&x);
71: PetscViewerDestroy(&fd);
72: PetscFinalize();
73: return 0;
74: }