dolfin team mailing list archive

["Garth N. Wells" <gnw20@xxxxxxxxx>]

On 04/07/11 16:44, Anders Logg wrote:
> On Mon, Jul 04, 2011 at 04:39:04PM +0100, Garth N. Wells wrote:
>> I'm not sold on the NonlinearVariationalProblem interface. I would
>> prefer a constructor takes the Jacobian as an argument. It's much
>> cleaner to do things at construction and removes the need to later
>> attach the Jacobian.
> 
> The point is that one should be able to define a nonlinear problem
> with or without a Jacobian. Not all nonlinear solvers need a Jacobian.
> 

That's why I wrote 'a' constructor. We can have two versions.

> I agree that it's in general cleaner to require as much data as
> possible at the time of construction, but think that the handling of
> the Jacobian data is quite clean: it's a shared pointer that may be
> null and the nonlinear solver can call has_jacobian to check whether
> it has been specified.
>

Which we can still do with two constructors.

Garth

> --
> Anders