static PetscErrorCode CreateBoundaryMesh(DM dm, DMLabel *bdLabel, DM *subdm, AppCtx *user)
{
DMLabel label;
PetscInt dim;
PetscErrorCode ierr;
PetscFunctionBeginUser;
ierr = DMLabelCreate(PETSC_COMM_SELF, "sub", &label);CHKERRQ(ierr);
ierr = DMPlexMarkBoundaryFaces(dm, 1, label);CHKERRQ(ierr);
ierr = DMPlexLabelComplete(dm, label);CHKERRQ(ierr);
ierr = DMPlexCreateSubmesh(dm, label, 1, PETSC_TRUE, subdm);CHKERRQ(ierr);
ierr = DMGetDimension(*subdm, &dim);CHKERRQ(ierr);
ierr = SetupDiscretization(*subdm, dim, user->cellSimplex, user);CHKERRQ(ierr);
ierr = PetscObjectSetName((PetscObject) *subdm, "boundary");CHKERRQ(ierr);
ierr = DMViewFromOptions(*subdm, NULL, "-sub_dm_view");CHKERRQ(ierr);
if (bdLabel) *bdLabel = label;
else ierr = DMLabelDestroy(&label);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PETSC_EXTERN void PETSC_STDCALL dmplexcreatesubmesh_(DM dm,DMLabel vertexLabel,PetscInt *value,DM *subdm, int *__ierr ){
*__ierr = DMPlexCreateSubmesh(
(DM)PetscToPointer((dm) ),
(DMLabel)PetscToPointer((vertexLabel) ),*value,subdm);
}
