Specifications

5 Arrays of LTI Models
5-12
Building LTI Arrays
There are several ways to build LTI arrays:
•Using a
for loop to assign each model in the array
•Using
stack to concatenate LTI models into an LTI array
•Using
tf, zpk, ss,orfrd
In addition, you can use the command rss to generate LTI arrays of random
state-space models.
Generating LTI Arrays Using rss
A convenient way to generate arrays of state-space models with the same
number of states in each model is to use
rss. The syntax is
rss(N,P,M,sdim1,...,sdimk)
where
•
N is the number of states of each model in the LTI array.
•
P is the number of outputs of each model in the LTI array.
•
M is the number of inputs of each model in the LTI array.
•
sdim1,...,sdimk are the lengths of the array dimensions.
For example, to create a 4-by-2 array of random state-space models with three
states, one output, and one input, type
sys = rss(3,2,1,4,2);
size(sys)
4x2 array of continuous-time state-space models
Each model has 2 outputs, 1 input, and 3 states.
Building LTI Arrays Using for Loops
Consider the following second-order SISO transfer function that depends on
two parameters, and
.
ζω
Hs()
ω
2
s
2
2ζωs ω
2
++
---------------------------------------
=