dolfin team mailing list archive

[Ola Skavhaug <skavhaug@xxxxxxxxx>]

Garth N. Wells skrev den 25/08-2008 følgende:
> Anders Logg wrote:
> > How should one use the eigenvalue solver to compute the N smallest
> > eigenvalues?
> > 
> > There seems to be a parameter "Eigenvalues to compute" that is used
> > internally in SLEPcEigenvalueSolver. Should this be used?
> >
> 
> 
> I would say with care. You'll probably need to do some work on 
> SLEPcEigenSolver and look into the SLEPc manual in you want to compute 
> the smallest eigenvalues efficiently. Most algorithms are designed to 
> find the largest and won't work for finding the smallest eigenvalues.
> 
> If you're interested in small systems, SLEPcEigenSolver can find all 
> eigenvalues using a direct method.

I've been playing with this, and my experience is that it is far from trivial
to make an efficient and robust SLEPcEigenvalueSolver.

Ola
 
> Garth
> 
> > 
> > 
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