dolfin team mailing list archive
-
dolfin team
-
Mailing list archive
-
Message #19836
Re: [Question #123984]: Second derivatives of variational form
On Wed, Sep 29, 2010 at 03:39:33PM -0000, Dominique wrote:
> Question #123984 on DOLFIN changed:
> https://answers.launchpad.net/dolfin/+question/123984
>
> Status: Answered => Open
>
> Dominique is still having a problem:
> A couple more questions about this:
>
> 1) I actually don't need the explicit rank 3 tensor, but I need to be
> able to compute tensor-vector products (which would result in matrices).
> Is this possible in DOLFIN? Is this what action() does?
>
> 2) Is there any chance rank 3 tensors will be available in DOLFIN in the
> near future? I'm willing to help if you have any starting point to
> suggest.
There are no such plans, but you are welcome to work on it.
You would need to find a suitable backend for higher-rank tensors and
add a wrapper for it, or implement a specialized subclass which has
all the necessary functionality in the GenericTensor interface and the
additional functionality you need.
The name of the subclass can be just 'Tensor' (since there are no
other competing Tensor classes). If you look at earlier versions of
DOLFIN, I think I implemented such a class at some point, which we
later removed. That might serve as a starting point (and data
structure).
--
Anders
References