hinfnorm 251
hinfnorm
Syntax
[out,omega] = hinfnorm(sys,tol,{imag eps,max it})
Parameter Li st
Inputs: sys Dynamic System, frequency response (pdm), or constant
gain (matrix).
sys Specifies the relative tolerance of the answer when the in-
put is a Dynamic SystemDefault = 0.001.
Keywords: imag eps Epsilon value for determining imaginary eigenvaluesof the
Hamiltonian. Default = sqrt(eps).
max it Maximum numberof iterations. Default = 100.
Outputs: out H∞norm of the input system. Scalar or pdm or matrix
input systems. 2×1 vector for Dynamic System inputs.
Anupp er bound of inf indicates that the maximum number
of iterations was exceeded.
omega Frequency (Hz) where the norm is achieved.
Description
The H∞norm is defined to be the supremum, over frequency,of the maximum singular
value of the system’s frequencyresp onse.
If the input system is a pdm, it is assumed to be a frequency response and the norm is
calculated only from the frequencies provided.
If the inputs system is a matrix, it represents a constant gain and the maximum singular
value of the matrix is returned. Note that this is NOT the same as the result of
norm(sys,inf).