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From: "Bruno Luong" <b.luong@fogale.findmycountry>
Newsgroups: comp.soft-sys.matlab
Subject: Re: inverse matrix inv pinv linfactor ginv
Date: Sun, 4 Oct 2009 14:46:01 +0000 (UTC)
Organization: FOGALE nanotech
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Rune Allnor <allnor@tele.ntnu.no> wrote in message <0d69cf8a-2563-4458-b112-401524512d0d@p36g2000vbn.googlegroups.com>...

> 
> ...which requires an equally expensive SVD to compute the
> norm before one calls the SVD to compute the PINV...
>

WRONG again, the norm estimation use Krylov space technique (Arnoldi iteration). With very few iterations on Rayleigh ratio will converge toward the norm. There is a difference between finding FEW eigenvalue (here once) and all of them.

Your turn to get a grip and open your old algebra book Rune.

Bruno