show_margins

Arguments

h

a SISO linear system (see :syslin).

Description

Given a SISO linear system in continuous or discrete time, show_margins display gain and phase margin and associated crossover frequencies on a bode (the defaut) or nyquist representation of the frequency response of the system.

Examples

//continuous case
h=syslin('c',0.02909+0.11827*%s+0.12823*%s^2+0.35659*%s^3+0.256*%s^4+0.1*%s^5,..
             0.0409+0.1827*%s+1.28225*%s^2+3.1909*%s^3+2.56*%s^4+%s^5);
show_margins(h)  
show_margins(h,'nyquist')

//discrete case
h = syslin(0.1,0.01547+0.01599*%z ,%z^2-1.81*%z+0.9048)
show_margins(h)
show_margins(h,'nyquist')

See Also

• p_margin — phase margin and associated crossover frequency
• g_margin — gain margin and associated crossover frequency
• bode — Bode plot
• nyquist — nyquist plot

Authors

Serge Steer, INRIA