How can you turn on 'All Stability Margins' when using the 'bode' function via script?

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Instead of right clicking on the bode plot and selecting Characteristics -> Minimum Stability Margins, how can I do this automatically via scripting? I don't want to manually do it. (Matlab 2012b)

Answers (2)

Arkadiy Turevskiy
Arkadiy Turevskiy on 11 Jul 2014
You can use function margin:
sys=tf(1,[1 1 0]);
margin(sys)

Erick Oberstar
Erick Oberstar on 17 Apr 2022
Edited: Erick Oberstar on 17 Apr 2022
As of Matlab 2020b I can verify this works for both nyqistplot and bodeplot functions
Ts= 0.01
n = [0 0.3680 0.2640];
d = [1.0 -1.368 0.3680];
Gz = tf(n,d,Ts)
Gz.Variable = 'z^-1'
figure; h1=nyquistplot(Gz)
axis([-1.5 1.5 -1.5 1.5]); grid on;
h1.showCharacteristic('AllStabilityMargins');
%zoomcp(h1);% Optional zoom in on critical point
figure; h2 = bodeplot(Gz)
h2.showCharacteristic('AllStabilityMargins');
Note this doesn't work if you generate the plots via "bode" or "nyquist"

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