dolfin team mailing list archive

[Johan Hake <hake@xxxxxxxxx>]

On Sunday 13 September 2009 20:32:18 Anders Logg wrote:
> On Fri, Sep 11, 2009 at 07:49:36AM -0000, Johan Hake wrote:
> > Blueprint changed by Johan Hake:
> >
> > Whiteboard changed to:
> >
> > Might also want LinearSystem and VariationalProblem as placeholders for
> > A, b and a, L, bcs. There would then be three ways to solve a problem:
> >
> >   x = solve(A, b)
> >   x = solver.solve(A, b)
> >   x = LinearSystem(A, b).solve()
> >
> > Johan Hake:
> > Why cannot LinearSolver and VariationalSolver act as this place holder?
> 
> Since (A, b) defines a linear system but not a linear solver. The
> solver attributes should be things like preconditioner, iterative
> method, tolerances etc.
> 
> I'm not sure we really need LinearSystem and VariationalProblem. It's
> something Marie requested. Let's discuss it further.

Ok, but if not VariationalSolver could act as a placeholder we would not need 
to distinguish between this and a LinearSolver. Then we could just overload 
the solve method for LinearSolver to also take a variational problem.

Would it make sense to have a LinearSystem and a VaritionalProblem, each 
having a LinearSolver? The LinearSolver has a solve method which overloads for 
both A,b and a,L?

Not sure I would ever use LinearSystem though...

Johan