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Elegant way to generate a transfer function matrix #325

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@iljastas

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@iljastas

Hi everybody,
I want to know if there is a more elegant way to generate a transfer-function-matrix for a hinf-controller.

In matlab I just do:
P11 = [0 0; W2G W2]
P12 = [W1; W2
G]
P21 = [G 1]
P22 = [G]
P_ = [P11 P12; P21 P22]
sys = ss(P_, 'minimal');

In python with control, I habe to do:
import control
from control import *
Gss = ss([[-1.0, -10.0], [1, 0]], [[10.0], [0]], [0, 1], [0])
G = tf(Gss)
W1 = tf([100], [0.1, 1])
W2 = tf([100], [0.1, 1])
W2G = W2*G
num = [ [ [0], [0], W1.num[0][0] ], [W2G.num[0][0], W2.num[0][0], G.num[0][0]], [G.num[0][0], [1], G.num[0][0] ] ]
den = [ [ [1], [1], W1.den[0][0] ], [W2G.den[0][0], W2.den[0][0], G.den[0][0]], [G.den[0][0], [1], G.den[0][0] ] ]
P = tf( num, den )
print(P)

The problem is that the return of the numerator and denominator is not directly the list.

And I get a high order system. Should I use just the balanced trunction?
Pss = ss(P)
Pbr = balred(Pss, 4)


Matlab is using minreal with exist also in "control", but I have to find manually a suitable tolerance...

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