xref: /petsc/src/mat/tests/ex107.c (revision 40badf4fbc550ac1f60bd080eaff6de6d55b946d)
1 
2 static char help[] = "Test MatCreate() with MAT_STRUCTURE_ONLY .\n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc,char **argv)
7 {
8   Mat            mat;
9   PetscInt       m = 7,n,i,j,rstart,rend;
10   PetscErrorCode ierr;
11   PetscMPIInt    size;
12   PetscScalar    v;
13   PetscBool      struct_only=PETSC_TRUE;
14 
15   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
16   CHKERRMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
17   PetscCheckFalse(size != 1,PETSC_COMM_WORLD,PETSC_ERR_SUP,"This is a uniprocessor example only!");
18 
19   CHKERRQ(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_COMMON));
20   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL));
21   CHKERRQ(PetscOptionsGetBool(NULL,NULL,"-struct_only",&struct_only,NULL));
22   n    = m;
23 
24   /* ------- Assemble matrix, test MatValid() --------- */
25   CHKERRQ(MatCreate(PETSC_COMM_WORLD,&mat));
26   CHKERRQ(MatSetSizes(mat,PETSC_DECIDE,PETSC_DECIDE,m,n));
27   CHKERRQ(MatSetFromOptions(mat));
28   if (struct_only) {
29     CHKERRQ(MatSetOption(mat,MAT_STRUCTURE_ONLY,PETSC_TRUE));
30   }
31   CHKERRQ(MatSetUp(mat));
32   CHKERRQ(MatGetOwnershipRange(mat,&rstart,&rend));
33   for (i=rstart; i<rend; i++) {
34     for (j=0; j<n; j++) {
35       v    = 10.0*i+j;
36       CHKERRQ(MatSetValues(mat,1,&i,1,&j,&v,INSERT_VALUES));
37     }
38   }
39   CHKERRQ(MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY));
40   CHKERRQ(MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY));
41   CHKERRQ(MatView(mat,PETSC_VIEWER_STDOUT_WORLD));
42 
43   /* Free data structures */
44   CHKERRQ(MatDestroy(&mat));
45   ierr = PetscFinalize();
46   return ierr;
47 }
48 
49 /*TEST
50 
51    test:
52       output_file: output/ex107.out
53 
54    test:
55       suffix: 2
56       args: -mat_type baij -mat_block_size 2 -m 10
57 
58 TEST*/
59