fresonpeak frequenciesSyntaxfr=freson(h)Argumentsh
A siso linear dynamical system, in state space, transfer function or zpk representations.
frvector of peak frequencies in HzDescription
returns the vector frequencies at which the response
amplitude of a siso dynamical system is a relative maximum
also called resonance frequencies.
ExamplesContinuous time system
h=syslin('c',-1+%s,(3+2*%s+%s^2)*(50+0.1*%s+%s^2));
fr=freson(h)
clf;bode(h);
fig=gcf();sca(fig.children(2));
[phi,db]=phasemag(repfreq(h,fr));
plot(fr,db(:),'+r');
Discrete time system
h=syslin('c',-1+%s,(3+2*%s+%s^2)*(50+0.1*%s+%s^2));
hd=dscr(h,0.05);
fr=freson(hd);
clf;bode(hd);
fig=gcf();sca(fig.children(2));
[phi,db]=phasemag(repfreq(hd,fr));
plot(fr,db(:),'+r');
See also
frep2tf
zgrid
h_norm
History6.0handling discrete systems and zpk
representation, peak detection improved.