dolfin team mailing list archive

[Anders Logg <logg@xxxxxxxxx>]

On Fri, May 09, 2008 at 08:34:02AM +0100, Garth N. Wells wrote:
> 
> 
> Anders Logg wrote:
> > On Thu, May 08, 2008 at 09:52:36PM +0100, Garth N. Wells wrote:
> >> DOLFIN wrote:
> >>> One or more new changesets pushed to the primary dolfin
> >>> repository. A short summary of the last three changesets is
> >>> included below.
> >>> 
> >>> changeset:   4179:fff523005c3840bc0428a9efec6fc49dbcd69789 tag:
> >>> tip user:        Anders Logg <logg@xxxxxxxxx> date:        Thu
> >>> May 08 22:11:29 2008 +0200 files:       ChangeLog
> >>> dolfin/la/GMRES.cpp dolfin/la/GMRES.h dolfin/la/LU.cpp
> >>> dolfin/la/LU.h dolfin/la/dolfin_la.h
> >>> dolfin/swig/dolfin_docstrings.i dolfin/swig/dolfin_headers.i
> >>> site-packages/dolfin/__init__.py description: Remove LU and GMRES
> >>> classes, use solve instead
> >>> 
> >> How can we create a default solver (e.g. LU) which is re-used?
> >> 
> >> Garth
> > 
> > You can do
> > 
> > LUSolver solver;
> > 
> > or
> > 
> > KrylovSolver solver(gmres, amg);
> > 
> > But I guess that's not what you mean?
> > 
> 
> Yes, that's it. I mistakenly thought LUSolver was called LU.

ok.

When I think of it, it would be very easy to make LinearSolver into a
general solver class so that one can do

  LinearSolver solver(lu);
  solver.solve(A, x, b);
  solver.solve(A, x, b);

or

  LinearSolver solver(gmres, ilu);
  solver.solve(A, x, b);
  solver.solve(A, x, b);

This would require changing the meaning of the current LinearSolver
class from being a base class for linear solvers to being a wrapper
class (it would be very small and simple).

The only place I think this is used right now is in the NewtonSolver,
but I think it would be easy to modify the NewtonSolver.

What do you think?

-- 
Anders