xref: /petsc/src/mat/tests/ex25.c (revision ffa8c5705e8ab2cf85ee1d14dbe507a6e2eb5283)
1 
2 static char help[] = "Tests MatTranspose()\n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc,char **args)
7 {
8   Mat            C,A;
9   PetscScalar    v;
10   PetscInt       i,j,m = 4,n = 4,Ii,J,Istart,Iend;
11   PetscMPIInt    rank,size;
12   PetscBool      equal=PETSC_FALSE;
13 
14   PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
15   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));
16   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
17 
18   PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL));
19   n    = m;
20 
21   PetscCall(MatCreateAIJ(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n,5,NULL,5,NULL,&C));
22 
23   /* create the symmetric matrix for the five point stencil */
24   PetscCall(MatGetOwnershipRange(C,&Istart,&Iend));
25   for (Ii=Istart; Ii<Iend; Ii++) {
26     v = -1.0; i = Ii/n; j = Ii - i*n;
27     if (i>0)   {J = Ii - n; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
28     if (i<m-1) {J = Ii + n; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
29     if (j>0)   {J = Ii - 1; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
30     if (j<n-1) {J = Ii + 1; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
31     v = 4.0; PetscCall(MatSetValues(C,1,&Ii,1,&Ii,&v,INSERT_VALUES));
32   }
33   PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY));
34   PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY));
35 
36   PetscCall(MatTranspose(C,MAT_INITIAL_MATRIX,&A));
37 
38   PetscCall(MatEqual(C,A,&equal));
39   PetscCheck(equal,PETSC_COMM_SELF,PETSC_ERR_SUP,"C != C^T");
40 
41   PetscCall(MatDestroy(&C));
42   PetscCall(MatDestroy(&A));
43   PetscCall(PetscFinalize());
44   return 0;
45 }
46 
47 /*TEST
48 
49    test:
50 
51 TEST*/
52