Using Hexahedron Element

FFC can't handle hexahedra, only intervals, triangles and tetrahedra.

--
Anders

On Thu, Aug 25, 2011 at 12:50:47PM -0000, Liang Jin Lim wrote:
> New question #169147 on UFL:
> https://answers.launchpad.net/ufl/+question/169147
>
> I am trying to use a hexahedron element, but thing goes wrong when I compile using FFC. No problem arises when I use a tetrahedron element. This is the my ufl code:
>
> ------------------------------------------------------------------------------------------------
> element = VectorElement("CG", "hexahedron", 1)
>
> u = TrialFunction(element)
> v = TestFunction(element)
> f = Coefficient(element)
> #g = Coefficient(element)
>
> mu = Constant("hexahedron")
> lmbda = Constant("hexahedron")
>
> def epsilon(v):
> return 0.5*(grad(v) + grad(v).T)
>
> def sigma(v):
> return 2.0*mu*epsilon(v) + lmbda*tr(epsilon(v))*Identity(v.cell().d)
>
> a = inner(sigma(u), epsilon(v))*dx
> L = inner(f, v)*dx
> ------------------------------------------------------------------------------------------------------
>
> And this is the error I got while compiling
>
> //...
> Compiler stage 4: Generating code
> ---------------------------------
> Generating code for 3 elements
>
> *** FFC: 'hexahedron'
> *** FFC: To get more information about this error, rerun FFC with --verbose.
>

So, there is no work around to use Hexahedron element?

Thanks Anders Logg, that solved my question.