svplot - singular-value sigma-plot
computes for the system sl=(A,B,C,D) the singular values of its transfer function matrix:
G(jw) = C(jw*I-A)B^-1+D
or
G(exp(jw)) = C(exp(jw)*I-A)B^-1+D
or
G(exp(jwT)) = C(exp(jw*T)*I-A)B^-1+D
evaluated over the frequency range specified by w . (T is the sampling period, T=sl('dt') for sampled systems).
sl is a syslin list representing the system [A,B,C,D] in state-space form. sl can be continous or discrete time or sampled system.
The i -th column of the output matrix SVM contains the singular values of G for the i -th frequency value w(i) .
SVM = svplot(sl)
is equivalent to
SVM = svplot(sl,logspace(-3,3)) (continuous)
SVM = svplot(sl,logspace(-3,%pi)) (discrete)
x=logspace(-3,3);
y=svplot(ssrand(2,2,4),x);
xbasc();plot2d1("oln",x',20*log(y')/log(10));
xgrid(12)
xtitle("Singular values plot","(Rd/sec)", "Db");
F.D; ;