User`s guide

4 Arrays of LTI Models
4-12
Building LTI Arrays
There are several ways to b uild 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 ad dition, 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, a nd 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
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