Actual source code: ex176.c
petsc-3.14.6 2021-03-30
2: static char help[] ="Tests MatCreateMPIAIJWithArrays() abd MatUpdateMPIAIJWithArrays()\n";
4: #include <petscmat.h>
6: /*
7: * This is an extremely simple example to test MatUpdateMPIAIJWithArrays()
8: *
9: * A =
11: 1 2 0 3 0 0
12: 0 4 5 0 0 6
13: 7 0 8 0 9 0
14: 0 10 11 12 0 13
15: 0 14 15 0 0 16
16: 17 0 0 0 0 18
17: *
18: * */
20: int main(int argc,char **argv)
21: {
23: Mat A;
24: PetscInt i[3][3] = {{0, 3, 6},{0, 3, 7},{0, 3, 5}};
25: PetscInt j[3][7] = {{0, 1, 3, 1, 2, 5, -1},{0, 2, 4, 1, 2, 3, 5},{1, 2, 5, 0, 5, -1, -1}};
26: PetscScalar a[3][7] = {{1, 2, 3, 4, 5, 6, -1}, {7, 8, 9, 10, 11, 12, 13},{14, 15, 16, 17, 18, -1, -1}};
27: PetscScalar anew[3][7] = {{10, 20, 30, 40, 50, 60, -1}, {70, 80, 90, 100, 110, 120, 130},{140, 150, 160, 170, 180, -1, -1}};
28: MPI_Comm comm;
29: PetscMPIInt rank,size;
31: PetscInitialize(&argc,&argv,NULL,help);if (ierr) return ierr;
32: comm = PETSC_COMM_WORLD;
33: MPI_Comm_rank(comm,&rank);
34: MPI_Comm_size(comm,&size);
35: if (size != 3) SETERRQ(comm,PETSC_ERR_ARG_INCOMP,"You have to use three MPI processes to run this example \n");
36: MatCreateMPIAIJWithArrays(comm,2,2,PETSC_DETERMINE,PETSC_DETERMINE,i[rank],j[rank],a[rank],&A);
37: MatView(A,NULL);
38: MatUpdateMPIAIJWithArrays(A,2,2,PETSC_DETERMINE,PETSC_DETERMINE,i[rank],j[rank],anew[rank]);
39: MatView(A,NULL);
40: MatUpdateMPIAIJWithArrays(A,2,2,PETSC_DETERMINE,PETSC_DETERMINE,i[rank],j[rank],a[rank]);
41: MatView(A,NULL);
42: MatDestroy(&A);
43: PetscFinalize();
44: return ierr;
45: }
47: /*TEST
48: test:
49: nsize: 3
51: TEST*/