Hi,
Consider the following code:
s = tf("s");
gs = 1/(s*(s+1));
gz = c2d(gs, 4, "zoh");
allmargin(gz)
gclz = zpk(feedback(gz,1,-1));
abs(gclz.P{1})
In R2024a, the stable flag given by allmargin is equal to one, indicating that the closed loop system is stable. On the other hand, the last sentence of the above code shows that the closed-loop system has a pole outside the unit circle, and therefore it is unstable. I do not have this issue in R2022b. Why the difference?

Sincerely
CarlosHi,
Consider the following code:
s = tf("s");
gs = 1/(s*(s+1));
gz = c2d(gs, 4, "zoh");
allmargin(gz)
gclz = zpk(feedback(gz,1,-1));
abs(gclz.P{1})
In R2024a, the stable flag given by allmargin is equal to one, indicating that the closed loop system is stable. On the other hand, the last sentence of the above code shows that the closed-loop system has a pole outside the unit circle, and therefore it is unstable. I do not have this issue in R2022b. Why the difference?

Sincerely
Carlos Hi,
Consider the following code:
s = tf("s");
gs = 1/(s*(s+1));
gz = c2d(gs, 4, "zoh");
allmargin(gz)
gclz = zpk(feedback(gz,1,-1));
abs(gclz.P{1})
In R2024a, the stable flag given by allmargin is equal to one, indicating that the closed loop system is stable. On the other hand, the last sentence of the above code shows that the closed-loop system has a pole outside the unit circle, and therefore it is unstable. I do not have this issue in R2022b. Why the difference?

Sincerely
Carlos allmargin MATLAB Answers — New Questions

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