Comment 3 for bug 844642

Anyway, the workaround is to provide a cell to the Constant.

Martin
Den 8. sep. 2011 13.59 skrev "Martin Sandve Alnæs" <email address hidden>
følgende:
> I need a concrete example to figure that out.
>
> Martin
> Den 8. sep. 2011 11.31 skrev "Garth Wells" <email address hidden>
> følgende:
>> On closer inspection, I do have a derivative. The problem is in taking
>> spatial derivatives of a Constant, which behind the scenes is a 'Real'.
>> Can UFL be updated to handle this case?
>>
>> --
>> You received this bug notification because you are a member of DOLFIN
>> Core Team, which is subscribed to DOLFIN.
>> https://bugs.launchpad.net/bugs/844642
>>
>> Title:
>> DOLFIN not attaching spatial dim to UFL functions (from Python)
>>
>> Status in DOLFIN:
>> Confirmed
>>
>> Bug description:
>> I'm getting a UFL error from the Python interface when using the UFL
>> commands lhs/rhs because UFL is not getting the spatial dim for
>> coefficient functions in forms. lhs/rhs calls expand_derivatives, and
>> then this bails out because the spatial dim is unknown (although I'm
>> taking derivatives of the coefficient function). I expect that DOLFIN
>> is failing to attach this data.
>>
>> I'll post a short piece of code soon and look into, unless someone
>> sees a quick fix.
>>
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