User`s guide

3 Linear Model Identification
To select all output or all input channels, use a colon (:). To select no
channels, specify an empty m atrix (
[]). If you need t o reference several
channel names, use a cell array of strings.
For example, to create a new model
m2 from m from inputs 1 ('power')and
4 ('speed') to output number 3 ('position'), use either of the following
equivalent commands:
m2 = m('position',{'power','speed'})
or
m2 = m(3,[1 4])
For a single-output model, you can use the following syntax to subreference
specific input channels without ambiguity:
m3 = m(inputs)
Similarly, for a single-input model, you can use the following syntax to
subreference spe cific output channels:
m4 = m(outputs)
Subreferencing Measured and Noise Models
For line ar models, the general symbolic model des cription is given by:
yGuHe=+
G is an operator that takes the measured inputs u to the outputs and captures
the system dynamics.
H is an operator that describes the propertie s of the additive output
disturbance and takes the hypothetical (unmeasured) noise source inputs to
the outputs. H represents the n oise model. W hen you specify to estimate a
noise model, the resulting model include one noise channel e at the inp ut for
each output in your system.
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