Re: run this in matlab for me

[Doug Stewart]

On Sat, Apr 13, 2019 at 4:51 AM Kai Torben Ohlhus <address@hidden> wrote:

On Sat, Apr 13, 2019 at 6:02 AM Doug Stewart <address@hidden> wrote:

One more try .

please run this in Matlab:

q1=((z^3-2*z^2+3*z+7)/(z +13))

aq=q1'

minreal(aq)

aq'

aaq=tf(ss(q1)')

q2=aaq'

minreal(q2)

--

DAS

I added "z = tf('z',1)" as first line according to an older post by you (https://lists.gnu.org/archive/html/octave-maintainers/2019-04/msg00089.html), this avoid the undefined "z" error.

The output for R2019a is:

z =

 

  z

 

Sample time: 1 seconds

Discrete-time transfer function.

q1 =

 

  z^3 - 2 z^2 + 3 z + 7

  ---------------------

         z + 13

 

Sample time: 1 seconds

Discrete-time transfer function.

aq =

 

  7 z^3 + 3 z^2 - 2 z + 1

  -----------------------

       13 z^3 + z^2

 

Sample time: 1 seconds

Discrete-time transfer function.

ans =

 

  0.5385 z^3 + 0.2308 z^2 - 0.1538 z + 0.07692

  --------------------------------------------

               z^3 + 0.07692 z^2

 

Sample time: 1 seconds

Discrete-time transfer function.

ans =

 

  z^3 - 2 z^2 + 3 z + 7

  ---------------------

         z + 13

 

Sample time: 1 seconds

Discrete-time transfer function.

aaq =

 

  0.5385 z^4 + 0.2308 z^3 - 0.1538 z^2 + 0.07692 z + 5.406e-19

  ------------------------------------------------------------

                       z^4 + 0.07692 z^3

 

Sample time: 1 seconds

Discrete-time transfer function.

q2 =

 

  5.406e-19 z^4 + 0.07692 z^3 - 0.1538 z^2 + 0.2308 z + 0.5385

  ------------------------------------------------------------

                         0.07692 z + 1

 

Sample time: 1 seconds

Discrete-time transfer function.

ans =

 

  7.028e-18 z^4 + z^3 - 2 z^2 + 3 z + 7

  -------------------------------------

                 z + 13

 

Sample time: 1 seconds

Discrete-time transfer function.

Best,

Kai

Thanks Kai

This verifies that my fixes are working properly.

--

DAS