Thank you Roy & John! That's great help. Appreciate it :) Best, Shawn
On Mon, Nov 12, 2018 at 4:21 PM John Peterson <jwpeter...@gmail.com> wrote: > > > On Mon, Nov 12, 2018 at 4:31 PM Stogner, Roy H <royst...@ices.utexas.edu> > wrote: > >> >> On Mon, 12 Nov 2018, Yuxiang Wang wrote: >> >> > Quick question: how do I get the n_nodes for a certain boundary set >> (given >> > bid)? I know I can do: >> > >> > MeshBase::const_node_iterator nodeit = >> > mesh.bid_nodes_begin(NODE_BOUNDARY_ID); >> > const MeshBase::const_node_iterator node_end = >> > mesh.bid_nodes_end(NODE_BOUNDARY_ID); >> > >> > to loop through all the nodes, but would there be a way to find out how >> > many nodes are there in the same set? >> >> Just std::distance, I believe. >> > > This might be a bit slow, depending on what else you are doing. Another > possibility would be to call: > > std::vector<std::tuple<dof_id_type, boundary_id_type>> vec > = mesh.get_boundary_info().build_node_list(); > > which returns a vector of _all_ the (node_id, boundary_id) pairs in the > mesh (they will be sorted by node_id). You could then count up the number > of entries with a specific boundary_id as needed... > > -- > John > -- Yuxiang "Shawn" Wang, PhD yw...@virginia.edu +1 (434) 284-0836 _______________________________________________ Libmesh-users mailing list Libmesh-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-users
