Path: news.mathworks.com!not-for-mail
From: Christopher Creutzig <Christopher.Creutzig@mathworks.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Matrix Minimal Polynomial
Date: Wed, 09 Nov 2011 14:11:40 +0100
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On 08.11.11 12:58, Pantelis S wrote:

> I guess MuPad uses symbolic algorithms to calculate the minimum polynomial - is there a function to do the same numerically? 

I don't think so. You probably could create something starting from
polyfun's poly.m (which computes the characteristic polynomial) by
checking the kernel before adding in another multiplicity of an
Eigenvalue, but off-hand I'm not sure if that is numerically stable.

> If not, is there a way to invoke linalg::minpoly from the workspace.

feval(symengine, 'expr', feval(symengine, 'linalg::minpoly', A, 'x'))

Kind of ugly, I know.



Christopher