Path: news.mathworks.com!not-for-mail
From: "John D'Errico" <woodchips@rochester.rr.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: eigenvector
Date: Thu, 28 Feb 2008 04:17:02 +0000 (UTC)
Organization: John D'Errico (1-3LEW5R)
Lines: 21
Message-ID: <fq5cju$3f0$1@fred.mathworks.com>
References: <fq550f$dpa$1@fred.mathworks.com> <16976388.1204166901909.JavaMail.jakarta@nitrogen.mathforum.org>
Reply-To: "John D'Errico" <woodchips@rochester.rr.com>
NNTP-Posting-Host: webapp-03-blr.mathworks.com
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 8bit
X-Trace: fred.mathworks.com 1204172222 3552 172.30.248.38 (28 Feb 2008 04:17:02 GMT)
X-Complaints-To: news@mathworks.com
NNTP-Posting-Date: Thu, 28 Feb 2008 04:17:02 +0000 (UTC)
X-Newsreader: MATLAB Central Newsreader 869215
Xref: news.mathworks.com comp.soft-sys.matlab:454221


dofour <dofour@hotmail.com> wrote in message 
<16976388.1204166901909.JavaMail.jakarta@nitrogen.mathforum.org>...
> Matlab gives the eigenvectors with norm 1,  I want the first eigenvector to 
be [1 1 1]. I don't know how to it from Matlab's eigenvectors
> 
> Thanks

Again, you can't ensure that an eigenvector will be
some specific vector, because in general, you can't
ensure that that vector is an eigenvector. You can't
just decide to pick some vector as an eigenvector,
at least not unless your matrix has a specific
property, like all of its eigenvalues are equal. And
in that case, ANY set of orthogonal vectors will
suffice.

Do you know that [1 1 1] is an eigenvector? If so,
then it will be scaled to have norm 1. So just rescale
the vector. WTP?

John