Re: SIMO systems

[A S Hodel]

That's a hole in the controls toolbox.  When my students and I wrote it 
(pre-MATLAB 5) we only did SISO tf/zp format.
ss will let you do MIMO/SIMO format.  This could probably use some work 
to select a better data format (perhaps
set up a new user-defined data type) and rewrite the toolbox to allow 
more flexibility like that.

| { ideas } | >> | time available |

so for now it's still just ideas.

On Thursday, July 31, 2003, at 01:50 AM, Geraint Paul Bevan wrote:

> Mauro Casse wrote:
> > Hi, I can't find how to do this, I must obtain the space state 
> > representation of the followig transfer function with single input 
> > and two outputs
> >                     1                [  1  ]
> > G(s) = ------------------- * |       | (this is a column vector)
> >              s^2+5*s+1       [ s+1]
> > the following commands works in Matlab, but octave return this error
> > octave:26> num = [ 0 1; 1 1];
> > octave:27> den = [ 1 5 6 ];
> > octave:28> [ A, B, C, D] = tf2ss(num,den)
> > error: num(2x2) must be a vector
> > error: evaluating if command near line 51, column 3
> > error: called from /usr/local/share/octave/2.1.50/m/control/sys
>
>
> tf2ss requires the numerator to have only one column, i.e. it only 
> works with simple gains in the numerator. You can create the state 
> space representation manually however:
>
>
> octave> [A,B,C1,D1] = tf2ss (    1  , [1,5,6] );
> octave> [A,B,C2,D2] = tf2ss ( [1,1] , [1,5,6] );
> octave> C = [C1;C2];
> octave> D = [D1;D2];
> octave> A,B,C,D
> A =
>
>    0   1
>   -6  -5
>
> B =
>
>   0
>   1
>
> C =
>
>   1  0
>   1  1
>
> D =
>
>   0
>   0
>
>
> --
> Geraint Bevan
> Department of Mechanical Engineering
> University of Glasgow
> Tel: +44 (0)141 330 5917
>
>
>
> -------------------------------------------------------------
> Octave is freely available under the terms of the GNU GPL.
>
> Octave's home on the web:  http://www.octave.org
> How to fund new projects:  http://www.octave.org/funding.html
> Subscription information:  http://www.octave.org/archive.html
> -------------------------------------------------------------
A. S. Hodel, Assoc. Prof, Dept. Elect & Comp Eng, Auburn University, AL 
36849-5201
(334) 844-1854 200 Broun Hall address@hidden
Auburn web page: http://www.eng.auburn.edu/~scotte
Personal web page: http://homepage.mac.com/hodelas



-------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
Subscription information:  http://www.octave.org/archive.html
-------------------------------------------------------------