svplot

singular-value sigma-plot

Calling Sequence

[SVM]=svplot(sl,[w])

Arguments

:sl syslin list (continuous, discrete or sampled system) : :w real vector (optional parameter) :

Description

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 continuous 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)

Examples

x=`logspace`_(-3,3);
y=svplot(`ssrand`_(2,2,4),x);
`clf`_();`plot2d1`_("oln",x',20*`log`_(y')/`log`_(10));
`xgrid`_(12)
`xtitle`_("Singular values plot","(Rd/sec)", "Db");