From: unbewusst.sein@... (=?ISO-8859-1?Q?Une_B=E9v?= =?ISO-8859-1?Q?ue?=)
Date: 2007-11-23T02:35:01+09:00
Subject: Re: eigenvector discrepency was (Re: [Matrix] eigenvalues, eigenvectors in Ruby ???)

Axel Etzold <AEtzold@gmx.de> wrote:

> 
> Yes, but that's not what I meant, as you can have different vectors
> mapped to the same vector under a matrix mapping.
> You'd have to check, whether, for a matrix m, the following holds:
> 
> for each v that is an eigenvector to m, and each corresponding eigenvalue
> c (vectors and numbers as delivered by the software),
> 
> m*v=c*v .


i did verify that, that' OK for two different matrices (a and b).
however those two matrices are different within a permutation which
normally (OK with GSL) i could find the permutation matrix p such that :

p * a * p^(-1) = b

this permutation matrix being computed by comparing an eigenvector of a
with the corresponding of b (same values different order) which i kind
find in case of ExtendMatrix...

-- 
Une B�vue