Re: control package, can't simulate complex systems

[Thomas D. Dean]

On 2020-06-10 11:26, Nicholas Jankowski wrote:
> On Wed, Jun 10, 2020 at 12:40 PM Doug Stewart <doug.dastew@gmail.com 
> <mailto:doug.dastew@gmail.com>> wrote:
>
>     try
>     step(ss(q))
>
>
> well that seemed to do the trick.  step(ss(q)) plots quickly in Octave, 
> and it matches the output produced in Matlab by  step(q) and step(ss(q))
>
> so, thoughts on why octave needs it converted into state-space 
> representation to avoid choking on it but Matlab doesn't?
I get an error with this.

q = tf(...)

error: '__lti_input_idx__' undefined near line 211, column 211
error: called from
    tf at line 211 column 31

octave:70> ver
----------------------------------------------------------------------
GNU Octave Version: 6.0.1 (hg id: ae94e3fad6d4)
GNU Octave License: GNU General Public License
Operating System: Linux 5.3.0-51-generic #44~18.04.2-Ubuntu SMP Thu Apr 
23 14:27:18 UTC 2020 x86_64
----------------------------------------------------------------------
Package Name        | Version | Installation directory
--------------------+---------+-----------------------
           control *|   3.2.0 | /home/tomdean/octave/control-3.2.0
    data-smoothing  |   1.3.0 | /home/tomdean/octave/data-smoothing-1.3.0
         financial  |   0.5.3 | /home/tomdean/octave/financial-0.5.3
          geometry  |   4.0.0 | /home/tomdean/octave/geometry-4.0.0
 image-acquisition  |   0.2.2 | 
/home/tomdean/octave/image-acquisition-0.2.2
instrument-control  |   0.5.0 | 
/home/tomdean/octave/instrument-control-0.5.0
                io  |   2.6.1 | /home/tomdean/octave/io-2.6.1
    linear-algebra  |   2.2.3 | /home/tomdean/octave/linear-algebra-2.2.3
           mapping  |   1.4.0 | /home/tomdean/octave/mapping-1.4.0
           matgeom  |   1.2.2 | /home/tomdean/octave/matgeom-1.2.2
               ocs  |   0.1.5 | /home/tomdean/octave/ocs-0.1.5
            odebvp  |   1.0.6 | /home/tomdean/octave/odebvp-1.0.6
            odepkg  |   0.9.1 | /home/tomdean/octave/odepkg-0.9.1
             optim  |   1.6.0 | /home/tomdean/octave/optim-1.6.0
            signal  |   1.4.1 | /home/tomdean/octave/signal-1.4.1
           sockets  |   1.2.0 | /home/tomdean/octave/sockets-1.2.0
           specfun  |   1.1.0 | /home/tomdean/octave/specfun-1.1.0
        statistics  |   1.4.2 | /home/tomdean/octave/statistics-1.4.2
            struct  |  1.0.16 | /home/tomdean/octave/struct-1.0.16
          symbolic  |   2.9.0 | /home/tomdean/octave/symbolic-2.9.0