xref: /petsc/src/mat/tests/ex81.c (revision e600fa544e2bb197ca2af9b6e65ea465976dec56)
1 
2 static char help[] = "Tests MatOption MAT_FORCE_DIAGONAL_ENTRIES.\n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc,char **args)
7 {
8   Mat            A,B;
9   Vec            diag;
10   PetscInt       i,n = 10,col[3],test;
11   PetscErrorCode ierr;
12   PetscScalar    v[3];
13 
14   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
15   ierr = PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);CHKERRQ(ierr);
16 
17   /* Create A which has empty 0-th row and column */
18   ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
19   ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n);CHKERRQ(ierr);
20   ierr = MatSetType(A,MATAIJ);CHKERRQ(ierr);
21   ierr = MatSetFromOptions(A);CHKERRQ(ierr);
22   ierr = MatSetUp(A);CHKERRQ(ierr);
23 
24   v[0] = -1.; v[1] = 2.; v[2] = -1.;
25   for (i=2; i<n-1; i++) {
26     col[0] = i-1; col[1] = i; col[2] = i+1;
27     ierr = MatSetValues(A,1,&i,3,col,v,INSERT_VALUES);CHKERRQ(ierr);
28   }
29   i    = 1; col[0] = 1; col[1] = 2;
30   ierr = MatSetValues(A,1,&i,2,col,v+1,INSERT_VALUES);CHKERRQ(ierr);
31   i    = n - 1; col[0] = n - 2; col[1] = n - 1;
32   ierr = MatSetValues(A,1,&i,2,col,v,INSERT_VALUES);CHKERRQ(ierr);
33   ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
34   ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
35 
36   for (test = 0; test < 2; test++) {
37     ierr = MatProductCreate(A,A,NULL,&B);CHKERRQ(ierr);
38 
39     if (test == 0) {
40       /* Compute B = A*A; B misses 0-th diagonal */
41       ierr = MatProductSetType(B,MATPRODUCT_AB);CHKERRQ(ierr);
42       ierr = MatSetOptionsPrefix(B,"AB_");CHKERRQ(ierr);
43     } else {
44       /* Compute B = A^t*A; B misses 0-th diagonal */
45       ierr = MatProductSetType(B,MATPRODUCT_AtB);CHKERRQ(ierr);
46       ierr = MatSetOptionsPrefix(B,"AtB_");CHKERRQ(ierr);
47     }
48 
49     /* Force allocate missing diagonal entries of B */
50     ierr = MatSetOption(B,MAT_FORCE_DIAGONAL_ENTRIES,PETSC_TRUE);CHKERRQ(ierr);
51     ierr = MatProductSetFromOptions(B);CHKERRQ(ierr);
52 
53     ierr = MatProductSymbolic(B);CHKERRQ(ierr);
54     ierr = MatProductNumeric(B);CHKERRQ(ierr);
55 
56     ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
57 
58     /* Insert entries to diagonal of B */
59     ierr = MatCreateVecs(B,NULL,&diag);CHKERRQ(ierr);
60     ierr = MatGetDiagonal(B,diag);CHKERRQ(ierr);
61     ierr = VecSetValue(diag,0,100.0,INSERT_VALUES);CHKERRQ(ierr);
62     ierr = VecAssemblyBegin(diag);CHKERRQ(ierr);
63     ierr = VecAssemblyEnd(diag);CHKERRQ(ierr);
64 
65     ierr = MatDiagonalSet(B,diag,INSERT_VALUES);CHKERRQ(ierr);
66     if (test == 1) {
67       ierr = MatView(B,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
68     }
69     ierr = MatDestroy(&B);CHKERRQ(ierr);
70     ierr = VecDestroy(&diag);CHKERRQ(ierr);
71   }
72 
73   ierr = MatDestroy(&A);CHKERRQ(ierr);
74   ierr = PetscFinalize();
75   return ierr;
76 }
77 
78 /*TEST
79 
80    test:
81      output_file: output/ex81_1.out
82 
83    test:
84      suffix: 2
85      args: -AtB_mat_product_algorithm at*b
86      output_file: output/ex81_1.out
87 
88    test:
89      suffix: 3
90      args: -AtB_mat_product_algorithm outerproduct
91      output_file: output/ex81_1.out
92 
93    test:
94      suffix: 4
95      nsize: 3
96      args: -AtB_mat_product_algorithm nonscalable
97      output_file: output/ex81_3.out
98 
99    test:
100      suffix: 5
101      nsize: 3
102      args: -AtB_mat_product_algorithm scalable
103      output_file: output/ex81_3.out
104 
105    test:
106      suffix: 6
107      nsize: 3
108      args: -AtB_mat_product_algorithm at*b
109      output_file: output/ex81_3.out
110 
111 TEST*/
112