1 static char help[] = "Tests converting a parallel AIJ formatted matrix to the parallel Row format.\n\
2 This also tests MatGetRow() and MatRestoreRow() for the parallel case.\n\n";
3
4 #include <petscmat.h>
5
main(int argc,char ** args)6 int main(int argc, char **args)
7 {
8 Mat C, A;
9 PetscInt i, j, m = 3, n = 2, Ii, J, rstart, rend, nz;
10 PetscMPIInt rank, size;
11 const PetscInt *idx;
12 PetscScalar v;
13 const PetscScalar *values;
14
15 PetscFunctionBeginUser;
16 PetscCall(PetscInitialize(&argc, &args, NULL, help));
17 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
18 PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
19 n = 2 * size;
20
21 /* create the matrix for the five point stencil, YET AGAIN*/
22 PetscCall(MatCreate(PETSC_COMM_WORLD, &C));
23 PetscCall(MatSetSizes(C, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n));
24 PetscCall(MatSetFromOptions(C));
25 PetscCall(MatMPIAIJSetPreallocation(C, 5, NULL, 5, NULL));
26 PetscCall(MatSeqAIJSetPreallocation(C, 5, NULL));
27 for (i = 0; i < m; i++) {
28 for (j = 2 * rank; j < 2 * rank + 2; j++) {
29 v = -1.0;
30 Ii = j + n * i;
31 if (i > 0) {
32 J = Ii - n;
33 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
34 }
35 if (i < m - 1) {
36 J = Ii + n;
37 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
38 }
39 if (j > 0) {
40 J = Ii - 1;
41 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
42 }
43 if (j < n - 1) {
44 J = Ii + 1;
45 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
46 }
47 v = 4.0;
48 PetscCall(MatSetValues(C, 1, &Ii, 1, &Ii, &v, INSERT_VALUES));
49 }
50 }
51 PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
52 PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
53 PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_INFO));
54 PetscCall(MatView(C, PETSC_VIEWER_STDOUT_WORLD));
55 PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
56 PetscCall(MatView(C, PETSC_VIEWER_STDOUT_WORLD));
57
58 PetscCall(MatGetOwnershipRange(C, &rstart, &rend));
59 for (i = rstart; i < rend; i++) {
60 PetscCall(MatGetRow(C, i, &nz, &idx, &values));
61 PetscCall(PetscSynchronizedFPrintf(PETSC_COMM_WORLD, stdout, "[%d] get row %" PetscInt_FMT ": ", rank, i));
62 for (j = 0; j < nz; j++) PetscCall(PetscSynchronizedFPrintf(PETSC_COMM_WORLD, stdout, "%" PetscInt_FMT " %g ", idx[j], (double)PetscRealPart(values[j])));
63 PetscCall(PetscSynchronizedFPrintf(PETSC_COMM_WORLD, stdout, "\n"));
64 PetscCall(MatRestoreRow(C, i, &nz, &idx, &values));
65 }
66 PetscCall(PetscSynchronizedFlush(PETSC_COMM_WORLD, stdout));
67
68 PetscCall(MatConvert(C, MATSAME, MAT_INITIAL_MATRIX, &A));
69 PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_INFO));
70 PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
71 PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
72 PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
73
74 PetscCall(MatDestroy(&A));
75 PetscCall(MatDestroy(&C));
76 PetscCall(PetscFinalize());
77 return 0;
78 }
79
80 /*TEST
81
82 test:
83 args: -mat_type seqaij
84
85 TEST*/
86