Actual source code: ex71.c
petsc-3.13.6 2020-09-29
2: static char help[] = "Passes a sparse matrix to MATLAB.\n\n";
4: #include <petscmat.h>
6: int main(int argc,char **args)
7: {
9: PetscInt m = 4,n = 5,i,j,II,J;
10: PetscScalar one = 1.0,v;
11: Vec x;
12: Mat A;
14: PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
15: PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);
16: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
18: MatCreate(PETSC_COMM_WORLD,&A);
19: MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n);
20: MatSetFromOptions(A);
21: MatSetUp(A);
23: for (i=0; i<m; i++) {
24: for (j=0; j<n; j++) {
25: v = -1.0; II = j + n*i;
26: if (i>0) {J = II - n; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);}
27: if (i<m-1) {J = II + n; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);}
28: if (j>0) {J = II - 1; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);}
29: if (j<n-1) {J = II + 1; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);}
30: v = 4.0; MatSetValues(A,1,&II,1,&II,&v,INSERT_VALUES);
31: }
32: }
33: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
34: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
35: #if defined(PETSC_USE_SOCKET_VIEWER)
36: MatView(A,PETSC_VIEWER_SOCKET_WORLD);
37: #endif
38: VecCreateSeq(PETSC_COMM_SELF,m,&x);
39: VecSet(x,one);
40: #if defined(PETSC_USE_SOCKET_VIEWER)
41: VecView(x,PETSC_VIEWER_SOCKET_WORLD);
42: #endif
44: PetscSleep(30);
46: VecDestroy(&x);
47: MatDestroy(&A);
48: PetscFinalize();
49: return ierr;
50: }
52: /*TEST
54: test:
55: TODO: cannot test with socket viewer
57: TEST*/