xref: /petsc/src/ksp/pc/tests/ex7.c (revision 2f613bf53f46f9356e00a2ca2bd69453be72fc31)
1 
2 static char help[] = "Tests MatILUFactorSymbolic() on matrix with missing diagonal.\n\n";
3 
4 #include <petscmat.h>
5 #include <petscpc.h>
6 
7 int main(int argc,char **args)
8 {
9   Mat            C,A;
10   PetscInt       i,j;
11   PetscErrorCode ierr;
12   PetscScalar    v;
13   PC             pc;
14   Vec            xtmp;
15 
16   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
17   ierr = MatCreate(PETSC_COMM_WORLD,&C);CHKERRQ(ierr);
18   ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,3,3);CHKERRQ(ierr);
19   ierr = MatSetFromOptions(C);CHKERRQ(ierr);
20   ierr = MatSetUp(C);CHKERRQ(ierr);
21   ierr = VecCreateSeq(PETSC_COMM_WORLD,3,&xtmp);CHKERRQ(ierr);
22   i    = 0; j = 0; v = 4;
23   ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
24   i    = 0; j = 2; v = 1;
25   ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
26   i    = 1; j = 0; v = 1;
27   ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
28   i    = 1; j = 1; v = 4;
29   ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
30   i    = 2; j = 1; v = 1;
31   ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
32 
33   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
34   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
35 
36   ierr = MatView(C,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
37   ierr = PCCreate(PETSC_COMM_WORLD,&pc);CHKERRQ(ierr);
38   ierr = PCSetFromOptions(pc);CHKERRQ(ierr);
39   ierr = PCSetOperators(pc,C,C);CHKERRQ(ierr);
40   ierr = PCSetUp(pc);CHKERRQ(ierr);
41   ierr = PCFactorGetMatrix(pc,&A);CHKERRQ(ierr);
42   ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
43 
44   ierr = PCDestroy(&pc);CHKERRQ(ierr);
45   ierr = VecDestroy(&xtmp);CHKERRQ(ierr);
46   ierr = MatDestroy(&C);CHKERRQ(ierr);
47 
48   ierr = PetscFinalize();
49   return ierr;
50 }
51 
52