Creating and Manipulating Models

Indexing Into LTI Arrays

You can index into LTI arrays in much the same way as you would for multidimensional arrays to

• Access models
• Extract subsystems
• Reassign parts of an LTI array
• Delete parts of an LTI array

When you index into an LTI array sys, the indices should be organized according to the following format

where

• Outputs are indices that select output channels.
• Inputs are indices that select input channels.
• are indices into the array dimensions that select one model or a subset of models in the LTI array.

Note on Indexing into LTI Arrays of FRD models.   For FRD models, the array indices can be followed by the keyword 'frequency' and some expression selecting a subset of the frequency points as in

• sys (outputs, inputs, n1,...,nk, 'frequency', SelectedFreqs)
  

See Referencing FRD Models Through Frequencies for details on frequency point selection in FRD models.

The next sections discuss these topics:

• Accessing Particular Models in an LTI Array
• Extracting LTI Arrays of Subsystems
• Reassigning Parts of an LTI Array
• Deleting Parts of an LTI Array
• Example: Addition of Two LTI Arrays
• Dimension Requirements
• Special Cases for Operations on LTI Arrays

Generating Random LTI Arrays Using rss

Accessing Particular Models in an LTI Array

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