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From: "Sean " <sean.dewolski@nospamplease.umit.maine.edu>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Difficult matrix construction
Date: Thu, 7 Oct 2010 17:19:04 +0000 (UTC)
Organization: University of Maine
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"Dennis Belleter" <d.j.w.belleter@student.tue.nl> wrote in message <i8kv4t$cr1$1@fred.mathworks.com>...
> "Sean " <sean.dewolski@nospamplease.umit.maine.edu> wrote in message <i8ksro$b5v$1@fred.mathworks.com>...
> > "Dennis Belleter" <d.j.w.belleter@student.tue.nl> wrote in message <i8krvm$dm3$1@fred.mathworks.com>...
> > > I'm having some trouble designing a MatLab algorithm for the construction of a rather complicated matrix. The marix structure is as follows:
> > > 
> > > |  B                  0                     0          ....       0 |
> > > | A*B               B                     0          ....       0 |
> > > | A^2*B          A*B                  B          ....       0 |
> > > |   :                  :                     :            :         : |
> > > | A^(N-1)*B   A^(N-2)*B    A^(N-3)*B   ....      B |
> > > 
> > > where A and B are matrices as well.
> > > 
> > > I want to construct and use this matrix in an m-file for any arbitrary N.
> > > I hope that someone has an algorithm for the construction of this matrix and can help me.
> > 
> > Like this?
> > 
> > n = 4; %Must equal size of both dimensions of A and B
> > fancy_mat = B.*tril(A.^toeplitz(0:n-1));
> 
> Thanks Sean,
> 
> This works brilliant for scalar values, the only problem I have is dat A is a square matrix (2x2) and B is a collum (2x1). 
> Is it possible to do it in this manner for such a system?
> 
> Kind Regards,
> 
> Dennis

It's definitely possible but you didn't illustrate what elements of A go where and same for B.