Dear all, I would like your guidance on how to perform the assembly of different shape representations on the same triangulation and on the same loop through cells.

Let me try to explain a bit more. I have designed a grid containing two concentric squares (or circles). Additionally, I have a parametric representation T(alpha) that maps points (x,y) on the edges of the inner square (or circle) to points (x',y') on the edges of a desired shape contained inside the outer square (or circle). This is (x',y')=T(alpha;x,y), where the representation T depends on a parameter alpha. Now assume we have N different shapes that are labelled with the index m. We then have N parameters alpha_m, with m=1,2,...N. Then in the loop through the triangulation cells in the assembly process, I would like to be able for each cell to loop through different alpha_m, in order to generate the local FE matrices and load vectors corresponding to each of the modified triangulations corresponding to each of the N shapes. My guess is that somehow I should modify the following line: const FEValues<dim> &fe_v = hp_fe_v.get_present_fe_values (); and pass instead a FEValues that has been generated with the desired alpha_m. Below I provide a more complete sketch on how my code looks like. I am quite hesitant on where to start, and I would appreciate your insights on how to achieve having an assemly routine where I can pass different alpha_m per each cell in the loop through cells. I am grateful for any advise or hint on how to achieve this. Thanks in advance, Juan Carlos Araújo, PhD The way I work with one shape is the following: // Deaclare my environment PolarShapeManifold manifold; PolarManifold<dim> polar; TransfiniteInterpolationManifold<dim> inner_manifold; Triangulation<dim> triangulation; hp::DoFHandler<dim> dof_handler; hp::FECollection<dim> fe_collection; hp::MappingCollection<dim> mapping_collection; PETScWrappers::SparseMatrix system_matrix; PETScWrappers::MPI::Vector solution; // Constructor manifold ( alpha), dof_handler (triangulation),... // setup_system typename hp::DoFHandler<dim>::active_cell_iterator cell = dof_handler.begin_active(), endc = dof_handler.end(); for (; cell!=endc; ++cell) { cell->set_active_fe_index ( ... ); } dof_handler.distribute_dofs (fe_collection); ... // create_coarse_grid concentric_disks_inner_shape ( triangulation ); tria.set_manifold ( manifold_label, manifold ); tria.set_manifold ( layer_label, polar ); unsigned int not_curved = 1; inner_manifold.initialize(triangulation); tria.set_manifold (not_curved, inner_manifold); ... // Assembly hp::FEValues<dim> hp_fe_v ( mapping_collection, fe_collection, quadrature_collection, update_values | update_gradients | update_quadrature_points | update_JxW_values); FullMatrix<PetscScalar> cell_system; Vector<PetscScalar> cell_rhs; std::vector<types::global_dof_index> local_dof_indices; typename hp::DoFHandler<dim>::active_cell_iterator cell = dof_handler.begin_active(), endc = dof_handler.end(); for (; cell!=endc; ++cell) { const unsigned int dofs_per_cell = cell->get_fe().dofs_per_cell; cell_system.reinit (dofs_per_cell, dofs_per_cell); cell_rhs.reinit (dofs_per_cell); ... hp_fe_v.reinit (cell); const FEValues<dim> &fe_v = hp_fe_v.get_present_fe_values (); for (unsigned int q_point=0; q_point<fe_v. n_quadrature_points; ++q_point) { Point<dim> x = fe_v.quadrature_point (q_point); for (unsigned int i=0; i<dofs_per_cell; ++i){ for (unsigned int j=0; j<dofs_per_cell; ++j) { cell_system (i,j) += ( fe_v. shape_grad(i,q_point) * fe_v.shape_grad(j,q_point) -f(x) * // given f fe_v.shape_value(i,q_point) * fe_v.shape_value(j,q_point) ) * fe_v.JxW(q_point); } cell_rhs (i) += g(x) * // given g fe_v. shape_value(i,q_point) * fe_v.JxW(q_point); } } // q -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to dealii+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/92fc053d-ca4e-4830-bca0-2f211a9ba384%40googlegroups.com.