xref: /petsc/src/mat/tests/ex25.c (revision ebead697dbf761eb322f829370bbe90b3bd93fa3)
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   PetscFunctionBeginUser;
15   PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
16   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));
17   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
18 
19   PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL));
20   n    = m;
21 
22   PetscCall(MatCreateAIJ(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n,5,NULL,5,NULL,&C));
23 
24   /* create the symmetric matrix for the five point stencil */
25   PetscCall(MatGetOwnershipRange(C,&Istart,&Iend));
26   for (Ii=Istart; Ii<Iend; Ii++) {
27     v = -1.0; i = Ii/n; j = Ii - i*n;
28     if (i>0)   {J = Ii - n; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
29     if (i<m-1) {J = Ii + n; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
30     if (j>0)   {J = Ii - 1; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
31     if (j<n-1) {J = Ii + 1; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
32     v = 4.0; PetscCall(MatSetValues(C,1,&Ii,1,&Ii,&v,INSERT_VALUES));
33   }
34   PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY));
35   PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY));
36 
37   PetscCall(MatTranspose(C,MAT_INITIAL_MATRIX,&A));
38 
39   PetscCall(MatEqual(C,A,&equal));
40   PetscCheck(equal,PETSC_COMM_SELF,PETSC_ERR_SUP,"C != C^T");
41 
42   PetscCall(MatDestroy(&C));
43   PetscCall(MatDestroy(&A));
44   PetscCall(PetscFinalize());
45   return 0;
46 }
47 
48 /*TEST
49 
50    test:
51 
52 TEST*/
53