User`s guide

4 Arrays of LTI Models
4-22
selects the first two input channels, and the first output channel in each model
of the LTI array
A, and returns the resulting 5-by-2 array of one-output,
two-input subsystems.
You can also combine model selection with I/O selection within an LTI array.
For example, to access both:
• The state-space model in the
(3,2) array position
• Only the portion of that model relating the second input t o the first output
type
sys(1,2,3,2)
To access the subsystem from al l inputs to the first two output channels of this
same a rray entry, type
sys(1:2,:,3,2)
Reassigning Parts of an LTI Array
You can reassign entire models or portions of models in an LTI array. For
example,
sys = rss(4,3,2,5,2); % 5X2 array of state-space models
H = rss(4,1,1,5,2); % 5X2 array of SISO models
sys(1,2) = H
reassignsthe subsystemfrom input twoto output one, for all models in the LTI
array
sys. This SISO subsystem of e ach m o del in the LTI array is replaced
with th e L TI array
H of SISO models. This one-line assignment command i s
equivale nt to the follow ing 10-step nested
for loop.
for k = 1:5
for j = 1:2
sys(1,2,k,j) = H(:,:,k,j);
end
end
Notice th at you don’t have to use the array dimensions with this assignment.
This is because I/O selection applies to all models in the array when the array
indices are omitted.