1 static char help[] = "Shows how to add a new MatOperation to AIJ MatType\n\n";
2
3 #include <petscmat.h>
4 #include <petscblaslapack.h>
5
MatScaleUserImpl_SeqAIJ(Mat inA,PetscScalar alpha)6 static PetscErrorCode MatScaleUserImpl_SeqAIJ(Mat inA, PetscScalar alpha)
7 {
8 PetscFunctionBegin;
9 PetscCall(MatScale(inA, alpha));
10 PetscFunctionReturn(PETSC_SUCCESS);
11 }
12
13 extern PetscErrorCode MatScaleUserImpl(Mat, PetscScalar);
14
MatScaleUserImpl_MPIAIJ(Mat A,PetscScalar aa)15 static PetscErrorCode MatScaleUserImpl_MPIAIJ(Mat A, PetscScalar aa)
16 {
17 Mat AA, AB;
18
19 PetscFunctionBegin;
20 PetscCall(MatMPIAIJGetSeqAIJ(A, &AA, &AB, NULL));
21 PetscCall(MatScaleUserImpl(AA, aa));
22 PetscCall(MatScaleUserImpl(AB, aa));
23 PetscFunctionReturn(PETSC_SUCCESS);
24 }
25
26 /* This routine registers MatScaleUserImpl_SeqAIJ() and
27 MatScaleUserImpl_MPIAIJ() as methods providing MatScaleUserImpl()
28 functionality for SeqAIJ and MPIAIJ matrix-types */
RegisterMatScaleUserImpl(Mat mat)29 PetscErrorCode RegisterMatScaleUserImpl(Mat mat)
30 {
31 PetscMPIInt size;
32
33 PetscFunctionBegin;
34 PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)mat), &size));
35 if (size == 1) { /* SeqAIJ Matrix */
36 PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatScaleUserImpl_C", MatScaleUserImpl_SeqAIJ));
37 } else { /* MPIAIJ Matrix */
38 Mat AA, AB;
39 PetscCall(MatMPIAIJGetSeqAIJ(mat, &AA, &AB, NULL));
40 PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatScaleUserImpl_C", MatScaleUserImpl_MPIAIJ));
41 PetscCall(PetscObjectComposeFunction((PetscObject)AA, "MatScaleUserImpl_C", MatScaleUserImpl_SeqAIJ));
42 PetscCall(PetscObjectComposeFunction((PetscObject)AB, "MatScaleUserImpl_C", MatScaleUserImpl_SeqAIJ));
43 }
44 PetscFunctionReturn(PETSC_SUCCESS);
45 }
46
47 /* This routine deregisters MatScaleUserImpl_SeqAIJ() and
48 MatScaleUserImpl_MPIAIJ() as methods providing MatScaleUserImpl()
49 functionality for SeqAIJ and MPIAIJ matrix-types */
DeRegisterMatScaleUserImpl(Mat mat)50 PetscErrorCode DeRegisterMatScaleUserImpl(Mat mat)
51 {
52 PetscMPIInt size;
53
54 PetscFunctionBegin;
55 PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)mat), &size));
56 if (size == 1) { /* SeqAIJ Matrix */
57 PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatScaleUserImpl_C", NULL));
58 } else { /* MPIAIJ Matrix */
59 Mat AA, AB;
60 PetscCall(MatMPIAIJGetSeqAIJ(mat, &AA, &AB, NULL));
61 PetscCall(PetscObjectComposeFunction((PetscObject)mat, "MatScaleUserImpl_C", NULL));
62 PetscCall(PetscObjectComposeFunction((PetscObject)AA, "MatScaleUserImpl_C", NULL));
63 PetscCall(PetscObjectComposeFunction((PetscObject)AB, "MatScaleUserImpl_C", NULL));
64 }
65 PetscFunctionReturn(PETSC_SUCCESS);
66 }
67
68 /* this routines queries the already registered MatScaleUserImp_XXX
69 implementations for the given matrix, and calls the correct
70 routine. i.e if MatType is SeqAIJ, MatScaleUserImpl_SeqAIJ() gets
71 called, and if MatType is MPIAIJ, MatScaleUserImpl_MPIAIJ() gets
72 called */
MatScaleUserImpl(Mat mat,PetscScalar a)73 PetscErrorCode MatScaleUserImpl(Mat mat, PetscScalar a)
74 {
75 PetscErrorCode (*f)(Mat, PetscScalar);
76
77 PetscFunctionBegin;
78 PetscCall(PetscObjectQueryFunction((PetscObject)mat, "MatScaleUserImpl_C", &f));
79 if (f) PetscCall((*f)(mat, a));
80 PetscFunctionReturn(PETSC_SUCCESS);
81 }
82
83 /* Main user code that uses MatScaleUserImpl() */
84
main(int argc,char ** args)85 int main(int argc, char **args)
86 {
87 Mat mat;
88 PetscInt i, j, m = 2, n, Ii, J;
89 PetscScalar v, none = -1.0;
90 PetscMPIInt rank, size;
91
92 PetscFunctionBeginUser;
93 PetscCall(PetscInitialize(&argc, &args, NULL, help));
94 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
95 PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
96 n = 2 * size;
97
98 /* create the matrix */
99 PetscCall(MatCreate(PETSC_COMM_WORLD, &mat));
100 PetscCall(MatSetSizes(mat, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n));
101 PetscCall(MatSetType(mat, MATAIJ));
102 PetscCall(MatSetUp(mat));
103
104 /* register user defined MatScaleUser() operation for both SeqAIJ
105 and MPIAIJ types */
106 PetscCall(RegisterMatScaleUserImpl(mat));
107
108 /* assemble the matrix */
109 for (i = 0; i < m; i++) {
110 for (j = 2 * rank; j < 2 * rank + 2; j++) {
111 v = -1.0;
112 Ii = j + n * i;
113 if (i > 0) {
114 J = Ii - n;
115 PetscCall(MatSetValues(mat, 1, &Ii, 1, &J, &v, INSERT_VALUES));
116 }
117 if (i < m - 1) {
118 J = Ii + n;
119 PetscCall(MatSetValues(mat, 1, &Ii, 1, &J, &v, INSERT_VALUES));
120 }
121 if (j > 0) {
122 J = Ii - 1;
123 PetscCall(MatSetValues(mat, 1, &Ii, 1, &J, &v, INSERT_VALUES));
124 }
125 if (j < n - 1) {
126 J = Ii + 1;
127 PetscCall(MatSetValues(mat, 1, &Ii, 1, &J, &v, INSERT_VALUES));
128 }
129 v = 4.0;
130 PetscCall(MatSetValues(mat, 1, &Ii, 1, &Ii, &v, INSERT_VALUES));
131 }
132 }
133 PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
134 PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
135
136 /* check the matrix before and after scaling by -1.0 */
137 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Matrix _before_ MatScaleUserImpl() operation\n"));
138 PetscCall(MatView(mat, PETSC_VIEWER_STDOUT_WORLD));
139 PetscCall(MatScaleUserImpl(mat, none));
140 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Matrix _after_ MatScaleUserImpl() operation\n"));
141 PetscCall(MatView(mat, PETSC_VIEWER_STDOUT_WORLD));
142
143 /* deregister user defined MatScaleUser() operation for both SeqAIJ
144 and MPIAIJ types */
145 PetscCall(DeRegisterMatScaleUserImpl(mat));
146 PetscCall(MatDestroy(&mat));
147 PetscCall(PetscFinalize());
148 return 0;
149 }
150
151 /*TEST
152
153 test:
154
155 test:
156 suffix: 2
157 nsize: 2
158
159 TEST*/
160