Hi Prof Wolfgang, Thanks for the insight. I figured a way of implementing it without any interpolation, but to just use the normal traces of RT_0 in 2d at different time levels directly to get the normal traces of RT_0 in 3d(2Dspace-1Dtime mesh).
regards, Manu On Sunday, October 20, 2019 at 10:33:20 PM UTC-4, Wolfgang Bangerth wrote: > > On 10/11/19 6:17 PM, manuJayadharan wrote: > > > > *Question: *If I start by assuming that I have values of the > flux(approximated > > using RT_k elements for each fixed time step) at different points on the > red > > interface from my earlier computations in terms of dof_handler for > Omega_1 and > > solution_vectors for different time step, how do I efficiently use this > > information to interpolate this to a DGQ_k function so that this new > > interpolated function will give the normal trace of flux on the red > interface? > > I think this could be done with the help of FEFieldFunction class, but I > would > > like to know if there is a more efficient way of doing this using some > other > > function class. > > Do you want to represent the normal fluxes on the red mesh as a DGQ_k > function > *also* on the red mesh, or did you mean to say *blue* mesh? If the former, > then there is no need to interpolate: the normal traces of an RT_k field > in > the volume are in DGQ_k (as a field on the surface), so the interpolation > is > equivalent to just evaluating the RT_k's normal flux. > > In general, it is difficult to interpolate from one mesh to another > because it > requires doing the work that FEFieldFunction does -- namely, for a random > point at which you want the solution to be evaluated you have to find > which > cell (or, in your case, face) the point is in and then transform back to > the > reference cell. This is expensive. It's one of the reasons why people > don't > generally want to use non-matching DD methods any more :-) > > It's a different thing if you just have non-matching time levels on the > two > sides because in that case the interpolation at arbitrary times is > generally > just a linear combination of the solutions at the two involved time steps. > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > <javascript:> > www: http://www.math.colostate.edu/~bangerth/ > > -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/03b82699-0278-4fa3-bfae-0c7c975400bb%40googlegroups.com.
