Path: news.mathworks.com!not-for-mail
From: "Bruno Luong" <b.luong@fogale.findmycountry>
Newsgroups: comp.soft-sys.matlab
Subject: Re: eigenvector
Date: Sun, 16 Jun 2013 08:38:10 +0000 (UTC)
Organization: FOGALE nanotech
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Xref: news.mathworks.com comp.soft-sys.matlab:797657

"Remus " <remusac@yahoo.com> wrote in message <kpighh\$qj3\$1@newscl01ah.mathworks.com>...

>
> Hi guys,
> I'm also looking at this problem. To answer you question John, yes I know that 1p is an Eigenvector of A. Let A be a matrix which has sum of all rows = 0, then 1p (where p=dim(a)) is an eigenvector of A.
> For Example let A = [0 0 0; -1 1 0; -1 0 1]. the comand [V,D]=eig(A) returns the following eigenvectors:
> V = [0 0 .5774; 1 0 .5774; 0 1 .5774], which is correct but as posted in the thread it is not normalized to 1.

It *is* normalized to 1

>> A = [0 0 0; -1 1 0; -1 0 1]

A =

0     0     0
-1     1     0
-1     0     1

>> [V,D]=eig(A)

V =

0         0    0.5774
0    1.0000    0.5774
1.0000         0    0.5774

D =

1     0     0
0     1     0
0     0     0

>>  sqrt(sum(V.^2,1)) % compute l2-norm of 3 eigen vectors

ans =

1     1     1

>>

% Bruno