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Subject: Re: finding a matrix used in matrix transformation
Date: Wed, 10 Nov 2010 18:42:04 +0000 (UTC)
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"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <ibensb$8r6$1@fred.mathworks.com>...
> 
> > 
> >   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.