Interpolate FRD model
isys = interp(sys,freqs)
isys = interp(sys,freqs) interpolates the
frequency response data contained in the FRD model sys at
the frequencies freqs. interp,
which is an overloaded version of the MATLAB® function interp,
uses linear interpolation and returns an FRD model isys containing
the interpolated data at the new frequencies freqs.
If sys is an IDFRD model (requires System Identification Toolbox™ software),
the noise spectrum, if non-empty, is also interpolated. The response
and noise covariance data, if available, are also interpolated.
You should express the frequency values freqs in
the same units as sys.frequency. The frequency
values must lie between the smallest and largest frequency points
in sys (extrapolation is not supported).