xref: /petsc/src/mat/tests/ex4.c (revision a69119a591a03a9d906b29c0a4e9802e4d7c9795)
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   Mat         mat, submat, submat1, *submatrices;
8   PetscInt    m = 10, n = 10, i = 4, tmp, rstart, rend;
9   IS          irow, icol;
10   PetscScalar value = 1.0;
11   PetscViewer sviewer;
12   PetscBool   allA = PETSC_FALSE;
13 
14   PetscFunctionBeginUser;
15   PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
16   PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_COMMON));
17   PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_SELF, PETSC_VIEWER_ASCII_COMMON));
18 
19   PetscCall(MatCreate(PETSC_COMM_WORLD, &mat));
20   PetscCall(MatSetSizes(mat, PETSC_DECIDE, PETSC_DECIDE, m, n));
21   PetscCall(MatSetFromOptions(mat));
22   PetscCall(MatSetUp(mat));
23   PetscCall(MatGetOwnershipRange(mat, &rstart, &rend));
24   for (i = rstart; i < rend; i++) {
25     value = (PetscReal)i + 1;
26     tmp   = i % 5;
27     PetscCall(MatSetValues(mat, 1, &tmp, 1, &i, &value, INSERT_VALUES));
28   }
29   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
30   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
31   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "Original matrix\n"));
32   PetscCall(MatView(mat, PETSC_VIEWER_STDOUT_WORLD));
33 
34   /* Test MatCreateSubMatrix_XXX_All(), i.e., submatrix = A */
35   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_all", &allA, NULL));
36   if (allA) {
37     PetscCall(ISCreateStride(PETSC_COMM_SELF, m, 0, 1, &irow));
38     PetscCall(ISCreateStride(PETSC_COMM_SELF, n, 0, 1, &icol));
39     PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_INITIAL_MATRIX, &submatrices));
40     PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_REUSE_MATRIX, &submatrices));
41     submat = *submatrices;
42 
43     /* sviewer will cause the submatrices (one per processor) to be printed in the correct order */
44     PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nSubmatrices with all\n"));
45     PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "--------------------\n"));
46     PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
47     PetscCall(MatView(submat, sviewer));
48     PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
49     PetscCall(PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD));
50 
51     PetscCall(ISDestroy(&irow));
52     PetscCall(ISDestroy(&icol));
53 
54     /* test getting a reference on a submat */
55     PetscCall(PetscObjectReference((PetscObject)submat));
56     PetscCall(MatDestroySubMatrices(1, &submatrices));
57     PetscCall(MatDestroy(&submat));
58   }
59 
60   /* Form submatrix with rows 2-4 and columns 4-8 */
61   PetscCall(ISCreateStride(PETSC_COMM_SELF, 3, 2, 1, &irow));
62   PetscCall(ISCreateStride(PETSC_COMM_SELF, 5, 4, 1, &icol));
63   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_INITIAL_MATRIX, &submatrices));
64   submat = *submatrices;
65 
66   /* Test reuse submatrices */
67   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_REUSE_MATRIX, &submatrices));
68 
69   /* sviewer will cause the submatrices (one per processor) to be printed in the correct order */
70   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nSubmatrices\n"));
71   PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
72   PetscCall(MatView(submat, sviewer));
73   PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
74   PetscCall(PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD));
75   PetscCall(PetscObjectReference((PetscObject)submat));
76   PetscCall(MatDestroySubMatrices(1, &submatrices));
77   PetscCall(MatDestroy(&submat));
78 
79   /* Form submatrix with rows 2-4 and all columns */
80   PetscCall(ISDestroy(&icol));
81   PetscCall(ISCreateStride(PETSC_COMM_SELF, 10, 0, 1, &icol));
82   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_INITIAL_MATRIX, &submatrices));
83   PetscCall(MatCreateSubMatrices(mat, 1, &irow, &icol, MAT_REUSE_MATRIX, &submatrices));
84   submat = *submatrices;
85 
86   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "\nSubmatrices with allcolumns\n"));
87   PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
88   PetscCall(MatView(submat, sviewer));
89   PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
90   PetscCall(PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD));
91 
92   /* Test MatDuplicate */
93   PetscCall(MatDuplicate(submat, MAT_COPY_VALUES, &submat1));
94   PetscCall(MatDestroy(&submat1));
95 
96   /* Zero the original matrix */
97   PetscCall(PetscViewerASCIIPrintf(PETSC_VIEWER_STDOUT_WORLD, "Original zeroed matrix\n"));
98   PetscCall(MatZeroEntries(mat));
99   PetscCall(MatView(mat, PETSC_VIEWER_STDOUT_WORLD));
100 
101   PetscCall(ISDestroy(&irow));
102   PetscCall(ISDestroy(&icol));
103   PetscCall(PetscObjectReference((PetscObject)submat));
104   PetscCall(MatDestroySubMatrices(1, &submatrices));
105   PetscCall(MatDestroy(&submat));
106   PetscCall(MatDestroy(&mat));
107   PetscCall(PetscFinalize());
108   return 0;
109 }
110 
111 /*TEST
112 
113    test:
114       args: -mat_type aij
115 
116    test:
117       suffix: 2
118       args: -mat_type dense
119 
120    test:
121       suffix: 3
122       nsize: 3
123       args: -mat_type aij
124 
125    test:
126       suffix: 4
127       nsize: 3
128       args: -mat_type dense
129 
130    test:
131       suffix: 5
132       nsize: 3
133       args: -mat_type aij -test_all
134 
135 TEST*/
136