User`s guide

Model Dynamics
5-5
Here is an example of model analysis using some of these commands.
h = tf([4 8.4 30.8 60],[1 4.12 17.4 30.8 60])
Transfer function:
4 s^3 + 8.4 s^2 + 30.8 s + 60
---------------------------------------
s^4 + 4.12 s^3 + 17.4 s^2 + 30.8 s + 60
pole(h)
ans =
–1.7971 + 2.2137i
–1.7971 – 2.2137i
–0.2629 + 2.7039i
–0.2629 – 2.7039i
zero(h)
ans =
–0.0500 + 2.7382i
–0.0500 – 2.7382i
–2.0000
dcgain(h)
ans =
1
[ninf,fpeak] = norm(h,inf)% peak gain of freq. response
ninf =
1.3402 % peak gain
fpeak =
1.8537 % frequency where gain peaks