fredrikekre
commented
1 year ago Fixed by #545 I think. You have to explicitly renumber after close!, but I don't think things would be more efficient if we let users pass the order to close! and it would simply call renumber! after distributing dofs.
The DofHandler can be improved for multi-field problems. Currently only one distribution mode is implemented. For example taking two scalar fields a and b the call to
close!yields the discrete algebraic vector (a_1, b_1, a_2, b_2, ..., a_N, b_N). However, this form is not always preferable, because it yields a locally blocked system matrix. For problems like for example the steady state incompressible Navier-Stokes flows some preconditioners need globally blocked system - see deal ii example 57 for a concise description. The corresponding algebraic vector then becomes (a_1, a_2, ... , a_N, b_1, b_2, ... , b_N). This can be achieved by either callingrenumber!with a properly constructed permutation vector or by modifying__close!. Block preconditioners can then be constructed via BlockArrays.jlThis requires to add corresponding tests and a small example to showcase the usage.