dolfin team mailing list archive

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

On 05/01/11 15:12, Anders Logg wrote:
> On Wed, Jan 05, 2011 at 03:51:32PM +0100, Marie E. Rognes wrote:
> > On 01/05/2011 03:32 PM, Garth N. Wells wrote:
> >
> >      I wonder if the distinction now between linear and nonlinear problems is
> >      too subtle? Another way would be to have classes
> >
> >        LinearVariationalProblem
> >
> >      and
> >
> >        NonlinearVariationalProblem
> >
> >
> >
> >
> > I agree that the distinction in the interface can be called subtle (or
> > alternatively, "almost seamless"). But, I think I prefer keeping the input
> > minimal and rather giving more verbose feedback ("starting linear/nonlinear
> > solve", throwing errors if input is inconsistent etc) than increasing the
> > verbosity of the required input.
> >
> > Also cf. thread "VariationalProblem interface(s)" from Oct 20th for more
> > motivation behind this change.
>
> I tend to prefer overloading and like the shorter "VariationalProblem"
> for both linear and nonlinear problems.
>
> The rationale is that the most important argument is placed first:
>
>    F, F'
>    a, L

My first issue is that it's not easy to read. Scanning through a 
function, it's not immediately obvious that a problem is linear or 
nonlinear.

Another reason to separate linear and nonlinear clases is that there is 
almost no shared code (none?) in VariationalProblem.cpp, so it doesn't 
make much sense to roll linear and nonlinear cases into one class. The 
other point is that they will share few parameters - I would like 
eventually to have more options for how a nonlinear problem is solved.

Garth

> --
> Anders
>
> _______________________________________________
> Mailing list: https://launchpad.net/~dolfin
> Post to     : dolfin@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~dolfin
> More help   : https://help.launchpad.net/ListHelp