Re: Documentation of Eigenvalues[], Eigensystem[]
- To: mathgroup at smc.vnet.net
- Subject: [mg114240] Re: Documentation of Eigenvalues[], Eigensystem[]
- From: Daniel Lichtblau <danl at wolfram.com>
- Date: Sun, 28 Nov 2010 06:54:25 -0500 (EST)
----- Original Message -----
> From: "Roman" <rschmied at gmail.com>
> To: mathgroup at smc.vnet.net
> Sent: Saturday, November 27, 2010 2:47:55 AM
> Subject: [mg114223] Re: Documentation of Eigenvalues[], Eigensystem[]
> On Nov 26, 11:30 am, Peter Pein <pet... at dordos.net> wrote:
> > Am Mon, 22 Nov 2010 12:35:46 +0000 (UTC)
> > schrieb Murray Eisenberg <mur... at math.umass.edu>:
> >
> > > This is definitely a gap in the documentation.
> >
> > > To find out that Eigenvalues has a Method option is easy, though:
> >
> > > Options[Eigenvalues]
> > > {Cubics -> False, Method -> Automatic, Quartics -> False}
> >
> > > What is difficult (impossible), however, is to find out for a
> > > Method
> > > option -- and a number of functions have it -- is what the
> > > possible
> > > settings are.
> >
> > ...
> >
> > Eigenvalues[HilbertMatrix[4],Method->"foo"]
> > Eigenvalues::emeth: The method specified by Method -> foo should be
> > either Automatic, Arnoldi, or BandedMatrix.
> >
> > works often, not always.
>
> Michael,
> This is the method I used in the past, plus some info from the ARPACK
> documentation (since this is what the Arnoldi method ends up calling
> internally). I've summarized the resulting documentation here:
>
> http://groups.google.com/group/comp.soft-sys.math.mathematica/browse_thread/thread/2a41064c0dbe5d54/26f379d722f6e1c8?hl=en#26f379d722f6e1c8
> Roman
We have filed a suggestion to update the advanced numerical linear algebra documentation and reintegrate it into the available program documentation. I do not know when this will happen, though.
Daniel Lichtblau
Wolfram Research