[Octave-bug-tracker] [bug #63052] [octave forge] (control) Inverse operation with transfer function variables resulting in wrong results

[Doug Stewart]

Follow-up Comment #5, bug #63052 (project octave):

Wow that Matlab output looks totally wrong.

I think there is a problem in the control pkg.


clear
s=tf('s')

A=[ 0 0 0
    1 2 3
    0 0 0]

sii=[s 0 0
     0 s 0
     0 0 s]

sia=sii-A


This should be easy to do, but I get things like this

Transfer function 'sys' from input 'u9' to output ...

 y1:  0

 y2:  0

 y3:  1 s - 1.57e-16

I don't know where the - 1.57e-16 comes from --- it should be :

y3:   1 s 

I am still working on it but help would be accepted :-)
To see the round off error show up set a break point in
mtimes at line 58 and look at sys before and after that line.


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