xref: /petsc/src/mat/tests/ex108.c (revision a916153043bedfa1a5cd23fc2b8cd7320ba6b2e5)
1 static char help[] = "Testing MatCreateSeqBAIJWithArrays() and MatCreateSeqSBAIJWithArrays().\n\n";
2 
3 #include <petscmat.h>
4 
main(int argc,char ** argv)5 int main(int argc, char **argv)
6 {
7   Mat             A, B, As;
8   const PetscInt *ai, *aj;
9   PetscInt        i, j, k, nz, n, asi[] = {0, 2, 3, 4, 6, 7};
10   PetscInt        asj[] = {0, 4, 1, 2, 3, 4, 4};
11   PetscScalar     asa[7], *aa;
12   PetscRandom     rctx;
13   PetscMPIInt     size;
14   PetscBool       flg;
15 
16   PetscFunctionBeginUser;
17   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
18   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
19   PetscCheck(size == 1, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "This is a uniprocessor example only!");
20 
21   /* Create a aij matrix for checking */
22   PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, 5, 5, 2, NULL, &A));
23   PetscCall(MatSetOption(A, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));
24   PetscCall(PetscRandomCreate(PETSC_COMM_WORLD, &rctx));
25   PetscCall(PetscRandomSetFromOptions(rctx));
26 
27   k = 0;
28   for (i = 0; i < 5; i++) {
29     nz = asi[i + 1] - asi[i]; /* length of i_th row of A */
30     for (j = 0; j < nz; j++) {
31       PetscCall(PetscRandomGetValue(rctx, &asa[k]));
32       PetscCall(MatSetValues(A, 1, &i, 1, &asj[k], &asa[k], INSERT_VALUES));
33       if (i != asj[k]) { /* insert symmetric entry */
34         PetscCall(MatSetValues(A, 1, &asj[k], 1, &i, &asa[k], INSERT_VALUES));
35       }
36       k++;
37     }
38   }
39   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
40   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
41 
42   /* Create a baij matrix using MatCreateSeqBAIJWithArrays() */
43   PetscCall(MatGetRowIJ(A, 0, PETSC_FALSE, PETSC_FALSE, &n, &ai, &aj, &flg));
44   PetscCall(MatSeqAIJGetArray(A, &aa));
45   /* WARNING: This sharing is dangerous if either A or B is later assembled */
46   PetscCall(MatCreateSeqBAIJWithArrays(PETSC_COMM_SELF, 1, 5, 5, (PetscInt *)ai, (PetscInt *)aj, aa, &B));
47   PetscCall(MatSeqAIJRestoreArray(A, &aa));
48   PetscCall(MatRestoreRowIJ(A, 0, PETSC_FALSE, PETSC_FALSE, &n, &ai, &aj, &flg));
49   PetscCall(MatMultEqual(A, B, 10, &flg));
50   PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_ARG_NOTSAMETYPE, "MatMult(A,B) are NOT equal");
51 
52   /* Create a sbaij matrix using MatCreateSeqSBAIJWithArrays() */
53   PetscCall(MatCreateSeqSBAIJWithArrays(PETSC_COMM_SELF, 1, 5, 5, asi, asj, asa, &As));
54   PetscCall(MatMultEqual(A, As, 10, &flg));
55   PetscCheck(flg, PETSC_COMM_SELF, PETSC_ERR_ARG_NOTSAMETYPE, "MatMult(A,As) are NOT equal");
56 
57   /* Free spaces */
58   PetscCall(PetscRandomDestroy(&rctx));
59   PetscCall(MatDestroy(&A));
60   PetscCall(MatDestroy(&B));
61   PetscCall(MatDestroy(&As));
62   PetscCall(PetscFinalize());
63   return 0;
64 }
65 
66 /*TEST
67 
68   test:
69     output_file: output/empty.out
70 
71 TEST*/
72