[Dune] Applying an ISTL InverseOperator to multiple right-hand sides

[Bård Skaflestad]

Dear Carsten,

> Am 02.05.2010 22:28, schrieb Bård Skaflestad:
> > 
> >     krylov-method
> >       preconditioner
> >         foreach rhs
> 
> with this approach you will compute one step size for all right hand
> sides in the Krylov step. This might lead to suboptimal convergence
> compared to the approach where you solve the systems independently with
> optimal step size for each system.

Right.  I didn't think of that.  Silly me.  In light of this
information it is clearly better to structure our solver as

    Assemble matrix and right hand side(s)
    Form the MatrixAdapter operator
    Form the AMG preconditioner
    Construct linear solver object: linsolve

    for each rhs
        linsolve.apply(rhs)

Thanks a lot for your patience, all of you.  I feel enlightened.  Not
bad at all on a Monday morning in May ;-)


Best regards,
-- 
Bård Skaflestad                            <Bard.Skaflestad at sintef.no>
SINTEF ICT, Applied mathematics