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 > > > > > > > ------------------------------------------------------------------------ > > > > _______________________________________________ > > DOLFIN-dev mailing list > > [email protected] > > http://www.fenics.org/mailman/listinfo/dolfin-dev > > > _______________________________________________ > DOLFIN-dev mailing list > [email protected] > http://www.fenics.org/mailman/listinfo/dolfin-dev _______________________________________________ DOLFIN-dev mailing list [email protected] http://www.fenics.org/mailman/listinfo/dolfin-dev
