Hello Martin,
I haven't checked it yet, but probably we will have the same issues
there. I will have a look at it and then change it in the same fashion
as you did with interpolate_boundary_values. Further, I would propose to
change this part in the tutorials as well, because there are a few,
where it is done in the "wrong way", and then new users will get on the
wrong track. What do you think about that?
Best Regards,
Markus
Am 16.09.10 16:45, schrieb Martin Kronbichler:
Hi again,
Just a comment that when using the original
interpolate_boundary_values methods (that did not use the
ConstraintMatrix class) the values that were interpolated last were
the ones that were applied when there was contention. It sounds like
the current suggestion is to reverse the order of precedence so that
constraints already specified are not changed.
The original implementation without ConstraintMatrix results in the same
matrix as when we use the new method and construct the ConstraintMatrix
first with hanging nodes and then with boundary conditions, but do not
actually new constraints in case the dof is already constrained (as Luca
and I proposed to do now). So I think this will be uncritical.
Like Andrew says there will be a slight difference in the boundary
conditions that result if the order is reversed.
Well, it will still be possible to first call
interpolate_boundary_values and then make the hanging node constraints
(which do not add anything to dofs already constrained). The reverse
order, which should be the mathematically correct one when you need H1
conformity, did actually produce completely weird results before as soon
as an inhomogeneity was involved. Whereas the former does fine for
constant functions on the boundary.
I would appreciate if some of you (Luca, Andrew, Michael) could have a
look at the new version that I just checked in, especially the
documentation in deal.II/include/numerics/vectors.h and
lac/include/lac/constraint_matrix.h where I wrote about mixing hanging
nodes with Dirichlet conditions.
One question remains: What should we do with the other methods that
operate on the ConstraintMatrix with inhomogeneities, like
project_boundary_values_curl_conforming?
Best regards,
Martin
_______________________________________________
dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
_______________________________________________
dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
