xref: /petsc/src/mat/tests/ex4.c (revision df4cd43f92eaa320656440c40edb1046daee8f75)
1 
2 static char help[] = "Creates a matrix, inserts some values, and tests MatCreateSubMatrices() and MatZeroEntries().\n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc, char **argv)
7 {
8   Mat         mat, submat, submat1, *submatrices;
9   PetscInt    m = 10, n = 10, i = 4, tmp, rstart, rend;
10   IS          irow, icol;
11   PetscScalar value = 1.0;
12   PetscViewer sviewer;
13   PetscBool   allA = PETSC_FALSE;
14 
15   PetscFunctionBeginUser;
16   PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
17   PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_COMMON));
18   PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_SELF, PETSC_VIEWER_ASCII_COMMON));
19 
20   PetscCall(MatCreate(PETSC_COMM_WORLD, &mat));
21   PetscCall(MatSetSizes(mat, PETSC_DECIDE, PETSC_DECIDE, m, n));
22   PetscCall(MatSetFromOptions(mat));
23   PetscCall(MatSetUp(mat));
24   PetscCall(MatGetOwnershipRange(mat, &rstart, &rend));
25   for (i = rstart; i < rend; i++) {
26     value = (PetscReal)i + 1;
27     tmp   = i % 5;
28     PetscCall(MatSetValues(mat, 1, &tmp, 1, &i, &value, INSERT_VALUES));
29   }
30   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
31   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
32   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "Original matrix\n"));
33   PetscCall(MatView(mat, PETSC_VIEWER_STDOUT_WORLD));
34 
35   /* Test MatCreateSubMatrix_XXX_All(), i.e., submatrix = A */
36   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_all", &allA, NULL));
37   if (allA) {
38     PetscCall(ISCreateStride(PETSC_COMM_SELF, m, 0, 1, &irow));
39     PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &icol));
40     PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_INITIAL_MATRIX, &submatrices));
41     PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_REUSE_MATRIX, &submatrices));
42     submat = *submatrices;
43 
44     /* sviewer will cause the submatrices (one per processor) to be printed in the correct order */
45     PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nSubmatrices with all\n"));
46     PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "--------------------\n"));
47     PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
48     PetscCall(MatView(submat, sviewer));
49     PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
50     PetscCall(PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD));
51 
52     PetscCall(ISDestroy(&irow));
53     PetscCall(ISDestroy(&icol));
54 
55     /* test getting a reference on a submat */
56     PetscCall(PetscObjectReference((PetscObject)submat));
57     PetscCall(MatDestroySubMatrices(1, &submatrices));
58     PetscCall(MatDestroy(&submat));
59   }
60 
61   /* Form submatrix with rows 2-4 and columns 4-8 */
62   PetscCall(ISCreateStride(PETSC_COMM_SELF, 3, 2, 1, &irow));
63   PetscCall(ISCreateStride(PETSC_COMM_SELF, 5, 4, 1, &icol));
64   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_INITIAL_MATRIX, &submatrices));
65   submat = *submatrices;
66 
67   /* Test reuse submatrices */
68   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_REUSE_MATRIX, &submatrices));
69 
70   /* sviewer will cause the submatrices (one per processor) to be printed in the correct order */
71   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nSubmatrices\n"));
72   PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
73   PetscCall(MatView(submat, sviewer));
74   PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
75   PetscCall(PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD));
76   PetscCall(PetscObjectReference((PetscObject)submat));
77   PetscCall(MatDestroySubMatrices(1, &submatrices));
78   PetscCall(MatDestroy(&submat));
79 
80   /* Form submatrix with rows 2-4 and all columns */
81   PetscCall(ISDestroy(&icol));
82   PetscCall(ISCreateStride(PETSC_COMM_SELF, 10, 0, 1, &icol));
83   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_INITIAL_MATRIX, &submatrices));
84   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_REUSE_MATRIX, &submatrices));
85   submat = *submatrices;
86 
87   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nSubmatrices with allcolumns\n"));
88   PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
89   PetscCall(MatView(submat, sviewer));
90   PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
91   PetscCall(PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD));
92 
93   /* Test MatDuplicate */
94   PetscCall(MatDuplicate(submat, MAT_COPY_VALUES, &submat1));
95   PetscCall(MatDestroy(&submat1));
96 
97   /* Zero the original matrix */
98   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "Original zeroed matrix\n"));
99   PetscCall(MatZeroEntries(mat));
100   PetscCall(MatView(mat, PETSC_VIEWER_STDOUT_WORLD));
101 
102   PetscCall(ISDestroy(&irow));
103   PetscCall(ISDestroy(&icol));
104   PetscCall(PetscObjectReference((PetscObject)submat));
105   PetscCall(MatDestroySubMatrices(1, &submatrices));
106   PetscCall(MatDestroy(&submat));
107   PetscCall(MatDestroy(&mat));
108   PetscCall(PetscFinalize());
109   return 0;
110 }
111 
112 /*TEST
113 
114    test:
115       args: -mat_type aij
116 
117    test:
118       suffix: 2
119       args: -mat_type dense
120 
121    test:
122       suffix: 3
123       nsize: 3
124       args: -mat_type aij
125 
126    test:
127       suffix: 4
128       nsize: 3
129       args: -mat_type dense
130 
131    test:
132       suffix: 5
133       nsize: 3
134       args: -mat_type aij -test_all
135 
136 TEST*/
137