Actual source code: ex71.c


  2: static char help[] = "Passes a sparse matrix to MATLAB.\n\n";

  4: #include <petscmat.h>

  6: int main(int argc, char **args)
  7: {
  8:   PetscInt    m = 4, n = 5, i, j, II, J;
  9:   PetscScalar one = 1.0, v;
 10:   Vec         x;
 11:   Mat         A;

 14:   PetscInitialize(&argc, &args, (char *)0, help);
 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;
 26:       II = j + n * i;
 27:       if (i > 0) {
 28:         J = II - n;
 29:         MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES);
 30:       }
 31:       if (i < m - 1) {
 32:         J = II + n;
 33:         MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES);
 34:       }
 35:       if (j > 0) {
 36:         J = II - 1;
 37:         MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES);
 38:       }
 39:       if (j < n - 1) {
 40:         J = II + 1;
 41:         MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES);
 42:       }
 43:       v = 4.0;
 44:       MatSetValues(A, 1, &II, 1, &II, &v, INSERT_VALUES);
 45:     }
 46:   }
 47:   MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);
 48:   MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);
 49: #if defined(PETSC_USE_SOCKET_VIEWER)
 50:   MatView(A, PETSC_VIEWER_SOCKET_WORLD);
 51: #endif
 52:   VecCreateSeq(PETSC_COMM_SELF, m, &x);
 53:   VecSet(x, one);
 54: #if defined(PETSC_USE_SOCKET_VIEWER)
 55:   VecView(x, PETSC_VIEWER_SOCKET_WORLD);
 56: #endif

 58:   PetscSleep(30);

 60:   VecDestroy(&x);
 61:   MatDestroy(&A);
 62:   PetscFinalize();
 63:   return 0;
 64: }

 66: /*TEST

 68:    test:
 69:      TODO: cannot test with socket viewer

 71: TEST*/