Hello Juan Carlos,
the final global matrix gets the desired block structure, but the
local matrix does not. My first question is: *how to make the local
matrix have this block pattern as well?*
I think there is no elegant way in doing this. The local numbering of
degrees of freedom is made by the finite element itself and, thus, there
is in fact no possibility to change this ordering. The only improvement
I can imagine in your case is to do the reordering by a
matrix-matrix-multiplication instead of doing it by hand. Since the
local ordering of the degrees of freedom is always the same you could
build a transformation matrix, which maps the original ordering to your
desired ordering, a priori and could gain some speed.
another question that I have is *how to get the grid size of the
cell?* something like dx, or the diagonal h = sqrt(dx^2+dy^2+dz^2).
TriaAccessor::diameter is your friend.
Best Regards,
Markus
_______________________________________________
dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
