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Topic: Solving equation
Replies: 9   Last Post: May 24, 2012 3:44 PM

 Messages: [ Previous | Next ]
 Matt J Posts: 4,997 Registered: 11/28/09
Re: Solving equation
Posted: May 24, 2012 3:44 PM

"Frank " <allinone_2003@yahoo.com.hk> wrote in message <jpkoit\$p1i\$1@newscl01ah.mathworks.com>...
>
>
> Is the solution unique?

============

Without the constraints |x_i|=1, the solution will always be non-unique, because
an (M-2)-by-M can never be full-column rank.

Even with the constraints, though (and assuming you're looking for a least squares solution), the solution can be non-unique.
As a simple example, take A=eye(M-2,M) and b=zeros(M-2,1).
All x satisfying the constraints are solutions in this case.

Date Subject Author
5/24/12 Frank
5/24/12 Nasser Abbasi
5/24/12 Frank
5/24/12 Nasser Abbasi
5/24/12 Bruno Luong
5/24/12 Frank
5/24/12 Frank
5/24/12 Bruno Luong
5/24/12 Frank
5/24/12 Matt J