From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: finding a matrix used in matrix transformation
Date: Wed, 10 Nov 2010 18:42:04 +0000 (UTC)
Organization: Xoran Technologies
Lines: 16
Message-ID: <ibep1s$pob$>
References: <ibc1cs$61o$> <ibc2ic$mjm$> <ibc4lr$cjv$> <ibcjtb$1nt$> <ibckv4$8q2$> <ibd3k2$8l3$> <ibdhgb$k7j$> <ibed75$jiu$> <ibensb$8r6$>
Reply-To: <HIDDEN>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
X-Trace: 1289414524 26379 (10 Nov 2010 18:42:04 GMT)
NNTP-Posting-Date: Wed, 10 Nov 2010 18:42:04 +0000 (UTC)
X-Newsreader: MATLAB Central Newsreader 1440443
Xref: comp.soft-sys.matlab:685626

"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <ibensb$8r6$>...
> > 
> >   max( min (  norm( sum_i c(i)*M(:,:,i)*u)^2  ))
> > 
> Note that the above criteria (minimum singular value) is not helpful since max -> Inf if c=s*c' for s-> inf given c' any arbitrary coefficients such that sum_i c'(i)*M(:,:,i) is non singular.

I proably meant to have norm(c) bounded to 1 as well as norm(u). 

In any case, if you're going to solve this iteratively, it won't matterif max -> Inf. As soon as you reach an iteration where  

M=sum_i c(i)*Mbasis(:,:,i) 

is non-singular, you would terminate the algorithm, with M as your solution.