dolfin team mailing list archive

[Jack Hale <j.hale09@xxxxxxxxxxxxxx>]

Hi,

I've been looking to compare some approaches to solving the biharmonic
problem (mixed and primal weak forms) that appears in areas such as
plate bending. The primal formulation requires a subspace of H^2 to be
constructed.

It seems that when I try to declare something like:

V_3 = df.FunctionSpace(mesh, "Hermite", None)

I get the error:

RuntimeError: *** Error: Illegal degree for creation of function
space, not an integer: None

And upon the declaration to:

V_3 = df.FunctionSpace(mesh, "Hermite", 1)

I get the error:

ufl.log.UFLException: Degree "1" invalid for "Hermite" finite element,
should be None

I can see that the element has been implemented in both SyFi and FIAT,
but has it been implemented in SFC/FFC and Dolfin? If not (and I'm not
sure I have the skills to help, but would like to know) what needs to
be done to finish the implementation through to the Dolfin level?

Thanks for your help,

Jack Hale
Department of Aeronautics
Imperial College London