dolfin team mailing list archive

[Kent Andre <kent-and@xxxxxxxxx>]

On to., 2009-02-26 at 08:46 +0000, Garth N. Wells wrote:
> 
> Kent Andre wrote:
> > In Dolfin you have very little control over the algorithms used to solve
> > the linear system except that you can set a few parameters like
> > the solver and preconditioner and send it away to the backend. You
> > can of course do backend specific things. 
> > 
> > Say you want a different norm on the residual than the one supported by
> > the backend, or want have a null space that you don't want to be present
> > in the residual, or want to compute the eigenvalues as a substep in the
> > CG algorithms.  Such things, that at least I care a lot about, is very
> > easy to do if you add a few lines to the Krylov algorithm. 
> > It also makes block preconditioning a lot easier.
> > Hence, having the algorithms present in Python is a big thing,
> > I think. 
> >
> 
> I still don't see a motivation for scipy specifically. My point is that 
> there should be a concrete reason to work on integration because it will 
> naturally lead to an increase in the complexity of DOLFIN. We should be 
> cautious in integrating pure Python libraries since the Python and C++ 
> interfaces of DOLFIN will deviate. A strength is the present similarity 
> of the interfaces.
> 
> Garth

I agree with you on this. 

Kent