chgunits (Control System Toolbox)

Convert the frequency units of an FRD model

Syntax

sys = chgunits(sys,units)

Description

sys = chgunits(sys,units) converts the units of the frequency points stored in an FRD model, sys to units, where units is either of the strings 'Hz' or 'rad/s'. This operation changes the assigned frequencies by applying the appropriate (2*pi) scaling factor, and the 'Units' property is updated.

If the 'Units' field already matches units, no conversion is made.

Example

w = logspace(1,2,2);
sys = rss(3,1,1);
sys = frd(sys,w)
From input 'input 1' to:
  Frequency(rad/s)        output 1     
  ----------------        --------     
          10         0.293773+0.001033i
         100         0.294404+0.000109i
Continuous-time frequency response data.
sys = chgunits(sys,'Hz')
sys.freq
ans =
    1.5915
   15.9155