Hi Johannes
> The result however > is not what I want. The results are correct though. Think of two one-dimensional linear elements of unit length. Integrate a constant function f over them and them. Then \int f dx = 2f but the vector of nodal f will be [f/2, f, f/2] > It is not constant and at the boundaries the value > of the reconstructed function is too small. I believe this is the case, > because there are contributions to the value of the boundary dofs are > implicitly zero, as the cells for these contributions are not existing. no this is not correct. it's just that the supports of the functions are truncated at the boundary. Think of the 1D example again. The shape functions are nodally defined and are thus truncated on the boundary. > What is an appropriate way to do that? If you really want to scale based on the patch area of the nodal shape function then you could follow the approach in Hughes, The Finite Element Method, pg 229 where the shape functions are weighted as you suggest. Cheers Andrew > > Thank you in advance > > Regards > > Johannes Reinhardt > > > > > > > <free_boundary.cpp><notconstant.png>_______________________________________________ > dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii _______________________________________________ dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
