Hello, a follow-up question to the reconstruction of my program in hp:: design: Is there a way to use the MappingQEulerian on hp::FECollection's DoFHandler? I understand there is no such simple constructor, so would it make sense to loop over cells and apply the mapping to the DoFHandler on the respective cell and arrange the results, or is there even a more elaborate method?
Thanks and greetings Till -------- Weitergeleitete Nachricht -------- Von: Wolfgang Bangerth <[email protected]> An: [email protected] Kopie: Till Heinemann <[email protected]>, Markus Bürg <[email protected]>, Duc Vu <[email protected]> Betreff: Re: [deal.II] assembling a single system from two DoFHandlers Datum: Thu, 3 Dec 2009 08:08:38 -0600 > But is this FECollection policy only valid in hp namespace? As far as > I've not quite fully understood what this hp FEM does, but taking a > glimpse at the description it might be designed to use collections of FE > types and adaptively use them. In the hp FEM method, you typically use elements of different polynomial order on different cells. To do this, the FECollection stores all elements that you might want to use, and on each cell set the active_fe_index flag to indicate which element of the collection should be used on this one cell. Note that this collection then has a totally different meaning than FESystem which constructs *vector-valued* elements from simpler elements. Now, what Markus' suggestion means is that while the idea of the hp namespace was to use different polynomial degrees on different cells, there is nothing that prevents you from using this mechanism to also use different finite elements for different physics on cells that belong to different subregions. That wasn't the initial intention when writing the hp stuff, but it's a valid application of the code. > If it's not possible just to do sth similar with a FESystem, then I > guess I'll start getting into that hp stuff. Again, the FESystem is meant for an entirely different purpose, namely coupling simpler elements into a vector-valued element. W. ------------------------------------------------------------------------- Wolfgang Bangerth email: [email protected] www: http://www.math.tamu.edu/~bangerth/ _______________________________________________ dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
