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How to create Hermite FunctionSpace

+7 votes

How do I create a Cubic Hermite function space?

FunctionSpace(bmesh, 'HER', x) with x in {0,1,2,3} gives

UFLException: Degree "0" invalid for "Hermite" finite element, should be None.

but FunctionSpace(bmesh, 'HER', None) doesn't work either:

*** Error:   Unable to create function space.
*** Reason:  Illegal argument for degree, not an integer: None.
*** Where:   This error was encountered inside functionspace.py.
*** Process: 0
*** 
*** DOLFIN version: 1.3.0
asked Feb 25, 2014 by Nikolaus Rath FEniCS User (2,100 points)

1 Answer

+3 votes
 
Best answer

Hermite space is not supported by FFC (and DOLFIN).

answered Mar 1, 2014 by Jan Blechta FEniCS Expert (51,420 points)
selected Mar 3, 2014 by Nikolaus Rath

Does this apply to Morley elements to, even in version 1.5.0?

Yes, watch

>>> import ffc
>>> ffc.__version__
'1.5.0+'
>>> ffc.supported_elememts
['Brezzi-Douglas-Fortin-Marini', 'Brezzi-Douglas-Marini', 'Crouzeix-Raviart',
'Discontinuous Lagrange', 'Discontinuous Raviart-Thomas', 'Lagrange',
'Nedelec 1st kind H(curl)', 'Nedelec 2nd kind H(curl)', 'Raviart-Thomas']

Is it still the case in the 2017.1.0 release? If not, are there plans to introduce support for any H2 elements (Argyris, Hermite, Morley) in forthcoming releases?

BTW, the docs for 1.5.0 say that Argyris, Hermite and Morley elements are "only partly supported". What does it mean? To what extend are these elements supported?

>>> import ffc
>>> ffc.__version__
'2017.2.0.dev0'
>>> ffc.supported_elements
['Brezzi-Douglas-Fortin-Marini', 'Brezzi-Douglas-Marini', 'BrokenElement', 'Bubble', 'Crouzeix-Raviart', 'Discontinuous Lagrange', 'Discontinuous Raviart-Thomas', 'Discontinuous Taylor', 'EnrichedElement', 'Gauss-Legendre', 'Gauss-Lobatto-Legendre', 'HDiv Trace', 'Hellan-Herrmann-Johnson', 'Lagrange', 'Nedelec 1st kind H(curl)', 'Nedelec 2nd kind H(curl)', 'NodalEnrichedElement', 'Raviart-Thomas', 'Regge', 'TensorProductElement']

No immediate plans for C1 elements.

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