Wolfgang, Thank you for pointing me to these locations in the source code, that is very helpful!
It is quite simple to mimic what is happening in "average_of_shape_hessians" and "jump_in_shape_3rd_derivatives" to write a function "average_of_shape_3rd_derivatives". I am re-compling deal.ii right now with the changes I made; when it's done I will test the implementation. If and when the function works, I will follow the instructions here for contributing a patch: https://github.com/dealii/dealii/wiki/Contributing Best regards, -Sean On Saturday, June 22, 2024 at 7:13:59 PM UTC-4 Wolfgang Bangerth wrote: > On 6/20/24 22:04, Sean Carney wrote: > > > > I'm in the process of implementing a DG method for a 4th order problem, > which > > requires access to the average of the third derivative of the finite > element > > functions across an interface. I notice that the FEInterfaceValues class > has a > > "jump_in_shape_3rd_derivatives" function, but not the corresponding > function > > for the average. > > > > Any suggestions for how to implement this, specifically in the context > of [the > > face_worker part] the MeshWorker framework? > > Sean: > If you take a look at how the corresponding functions for the second > derivatives (Hessians) are implemented here > > https://github.com/dealii/dealii/blob/master/include/deal.II/fe/fe_interface_values.h#L3420-L3445 > and here > > https://github.com/dealii/dealii/blob/master/include/deal.II/fe/fe_interface_values.h#L3477-L3502 > then you will pretty immediately see how the implementation of the jump in > third derivatives in > > https://github.com/dealii/dealii/blob/master/include/deal.II/fe/fe_interface_values.h#L3449-L3473 > can be extended to compute the average. > > It would of course be great if you could make that a patch to deal.II that > we > could include in the next release! > > Best > Wolfgang > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > 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/b6a1d670-3809-4228-a4e1-bf878108aeb6n%40googlegroups.com.
