From: unbewusst.sein@... (=?ISO-8859-1?Q?Une_B=E9v?= =?ISO-8859-1?Q?ue?=)
Date: 2007-11-23T19:30:02+09:00
Subject: Re: eigenvector discrepency was (Re: [Matrix] eigenvalues, eigenvectors in Ruby ???)

Axel Etzold <AEtzold@gmx.de> wrote:

> 
> The permutation matrices are rotation matrices 
> (http://en.wikipedia.org/wiki/Rotation_matrix), 
> if and only if the permutation is even (the number 
> of elements exchanged is even). Then, they can be 
> decomposed into rotations of 45 degrees 
> (i.e. exchanges of coordinates x,y different planes).
> See also the article about orthogonal matrices :
> http://en.wikipedia.org/wiki/Orthogonal_matrix
>

[...]

> 
> The original is in German: Kombinatorische Anzahlbestimmungen f�r Gruppen,
> Graphen und chemische Verbindungen, Acta Mathematica, 68 (1937), 145-254,
> whichever you prefer :)

fine thanks a lot for all your references, i think as the name implies
for eigenvalues (@eigval = @extendmatrix.eigenvaluesJacobi) that's a
Jacobi method which i don't know for GSL.

Vielen dank !

-- 
Une B�vue