Is there any simple way in Getfem to impose lineic boundary conditions on a 3D problem ? To be more precise, I have a 3D mesh and I want to impose either Dirichlet or Neumann boundary conditions on a polyline. The first problem that arises is that, if I'm not wrong, the mesh_regions in 3D can be either volumes (convexes) or surfaces (convexe faces) but not 1D elements. However, as I can gather all the dof corresponding to the polyline, Dirichlet conditions can rather easily be handled by add_explicit_matrix and add_explicit_rhs methods. But the case of Neumann conditions may be a bit more difficult. Is there any straightforward method to do so ?
Thank you very much