From: unbewusst.sein@... (=?ISO-8859-1?Q?Une_B=E9v?= =?ISO-8859-1?Q?ue?=)
Date: 2007-11-24T07:55:03+09:00
Subject: Re: eigenvector discrepency was (Re: [Matrix] eigenvalues, eigenvectors in Ruby ???)

Axel Etzold <AEtzold@gmx.de> wrote:

> You'd choose QR over Jacobi, because the cube of 20 is much bigger
> than the square. You'll feel that if you have to do many calculations
> like that.

a rough estimate is about 1000 computations over 20X20 to 25X25
matrices.

unfortunately with the eigenvectors given by ExtendMatrix (Jacobi) i'm
unable, for the time being, to compute the permutation matrix giving one
molecule representation from the other (even for a test matrix of 4X4).
I don't understand why. Then i'll also explore, with GSL, other methods
for eigenvectors computation.

-- 
Une B�vue