Creating a rational model

The last possibility to build a transfer function model is to use the rational constructor, which implements a transfer function as a quotient of polynomials

% DESCRIPTION: RATIONAL rational representation of a transfer function.
%
%           a(1)s^m + a(2)s^{m-1} + ... + a(m+1)
%   H(s) = --------------------------------------
%           b(1)s^n + b(2)s^{n-1} + ... + b(n+1)
%

For example if the numerator and denominator coefficients are given by:

then we need to write down the following

>> m = rational([1 3 5],[1 8 10])
---- rational 1 ----
model:    None
num:      [1 3 5]
den:      [1 8 10]
iunits:   []
ounits:   []
--------------------

And now, as with the previous models, we can evaluate the response in a given frequency region

>> resp(m,plist('f1',0.1,'f2',10))

Response of a rational model