SingularValuePlot

SingularValuePlot[lsys] generates a plot of the singular values of the transfer function for the system lsys. 

SingularValuePlot[lsys,{ωmin,ωmax}] plots for the frequency range ωmin to ωmax.

SingularValuePlot[expr,{ω,ωmin,ωmax}] plots expr using the variable ω.

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