xref: /petsc/src/dm/tutorials/ex4.c (revision 4e8208cbcbc709572b8abe32f33c78b69c819375)
1c4762a1bSJed Brown static char help[] = "Demonstrates various vector routines for DMDA.\n\n";
2c4762a1bSJed Brown 
3c4762a1bSJed Brown /*
4c4762a1bSJed Brown   Include "petscpf.h" so that we can use pf functions and "petscdmda.h" so
5c4762a1bSJed Brown  we can use the PETSc distributed arrays
6c4762a1bSJed Brown */
7c4762a1bSJed Brown 
8c4762a1bSJed Brown #include <petscpf.h>
9c4762a1bSJed Brown #include <petscdm.h>
10c4762a1bSJed Brown #include <petscdmda.h>
11c4762a1bSJed Brown 
myfunction(PetscCtx ctx,PetscInt n,const PetscScalar * xy,PetscScalar * u)12*2a8381b2SBarry Smith PetscErrorCode myfunction(PetscCtx ctx, PetscInt n, const PetscScalar *xy, PetscScalar *u)
13d71ae5a4SJacob Faibussowitsch {
14c4762a1bSJed Brown   PetscInt i;
15c4762a1bSJed Brown 
16c4762a1bSJed Brown   PetscFunctionBeginUser;
17c4762a1bSJed Brown   for (i = 0; i < n; i++) {
18c4762a1bSJed Brown     u[2 * i]     = xy[2 * i];
19c4762a1bSJed Brown     u[2 * i + 1] = xy[2 * i + 1];
20c4762a1bSJed Brown   }
213ba16761SJacob Faibussowitsch   PetscFunctionReturn(PETSC_SUCCESS);
22c4762a1bSJed Brown }
23c4762a1bSJed Brown 
main(int argc,char ** argv)24d71ae5a4SJacob Faibussowitsch int main(int argc, char **argv)
25d71ae5a4SJacob Faibussowitsch {
26c4762a1bSJed Brown   Vec      u, xy;
27c4762a1bSJed Brown   DM       da;
28c4762a1bSJed Brown   PetscInt m = 10, n = 10, dof = 2;
29c4762a1bSJed Brown   PF       pf;
30c4762a1bSJed Brown 
31327415f7SBarry Smith   PetscFunctionBeginUser;
32c8025a54SPierre Jolivet   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
339566063dSJacob Faibussowitsch   PetscCall(DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DMDA_STENCIL_BOX, m, n, PETSC_DECIDE, PETSC_DECIDE, dof, 1, 0, 0, &da));
349566063dSJacob Faibussowitsch   PetscCall(DMSetFromOptions(da));
359566063dSJacob Faibussowitsch   PetscCall(DMSetUp(da));
369566063dSJacob Faibussowitsch   PetscCall(DMDASetUniformCoordinates(da, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0));
379566063dSJacob Faibussowitsch   PetscCall(DMCreateGlobalVector(da, &u));
389566063dSJacob Faibussowitsch   PetscCall(DMGetCoordinates(da, &xy));
39c4762a1bSJed Brown 
409566063dSJacob Faibussowitsch   PetscCall(DMDACreatePF(da, &pf));
419566063dSJacob Faibussowitsch   PetscCall(PFSet(pf, myfunction, 0, 0, 0, 0));
429566063dSJacob Faibussowitsch   PetscCall(PFSetFromOptions(pf));
43c4762a1bSJed Brown 
449566063dSJacob Faibussowitsch   PetscCall(PFApplyVec(pf, xy, u));
45c4762a1bSJed Brown 
469566063dSJacob Faibussowitsch   PetscCall(VecView(u, PETSC_VIEWER_DRAW_WORLD));
47c4762a1bSJed Brown 
48c4762a1bSJed Brown   /*
49c4762a1bSJed Brown      Free work space.  All PETSc objects should be destroyed when they
50c4762a1bSJed Brown      are no longer needed.
51c4762a1bSJed Brown   */
529566063dSJacob Faibussowitsch   PetscCall(VecDestroy(&u));
539566063dSJacob Faibussowitsch   PetscCall(PFDestroy(&pf));
549566063dSJacob Faibussowitsch   PetscCall(DMDestroy(&da));
559566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
56b122ec5aSJacob Faibussowitsch   return 0;
57c4762a1bSJed Brown }
58c4762a1bSJed Brown 
59c4762a1bSJed Brown /*TEST
60c4762a1bSJed Brown 
61c4762a1bSJed Brown    test:
623886731fSPierre Jolivet      output_file: output/empty.out
63c4762a1bSJed Brown 
64c4762a1bSJed Brown TEST*/
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