User`s guide

4 Arrays of LTI Models
4-8
Thenext figure illustrates the concepts of dimension and sizefor the LTI array
m2d, a 2-by-3 array of one-input, two-output transfer function models.
Figure 4-5: Dimensions and Size of m2d, an LTI Array
You can lo ad this sample L TI array into your workspace by t yping
load LTIexamples
size(m2d)
2x3 array of continuous-time transfer functions
Each transfer function has 2 outputs and 1 input.
According tothematrixanalogy in “Viewing LTI Systems As Matrices”on page
2-5, the I/O dimensions correspond to t he row and column dimensions of the
transfer matrix. The two I/O dimensions are both of length 1 for SISO models.
For MIMO models the lengths of these dimensions are given by the n umber of
outputs and inputs of the model.
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The length of the second array dimension is 3.
Input dimension (length 1)
Output dimension (length 2)
3.36
s 2.9+
-----------------
7.23
3.4
s 2.86+
--------------------
7.27
3.45
s 2.81+
--------------------
7.32
m2d(:,:,1,1) m2d(:,:,1,2) m2d(:,:,1,3)
m2d(:,:,2,1)
m2d(:,:,2,2)
m2d(:,:,2,3)
3.45
s 2.81+
--------------------
7.32
m2d(:,:,2,3)