Specify absence of nonlinearities for specific input or output channels in Hammerstein-Wiener models
unit=idUnitGain instantiates an object that specifies an identity mapping
F(x)=x to exclude specific input and output channels from being
affected by a nonlinearity in Hammerstein-Wiener models.
idUnitGain object as an argument in the
estimator to set the corresponding channel nonlinearity to unit gain.
For example, for a two-input and one-output model, to exclude the second input from being affected by a nonlinearity, use the following syntax:
m = nlhw(data,orders,['idSaturation''idUnitGain'],'idDeadZone')
In this case, the first input saturates and the output has an
idUnitGain does not have properties.
For example, for a one-input and one-output model, to exclude the output from being affected by a nonlinearity, use the following syntax:
m = nlhw(Data,Orders,'idSaturation','idUnitGain')
In this case, the input has a saturation nonlinearity.
If nonlinearities are absent in input or output channels, you can replace
idUnitGain with an empty matrix. For example, to specify a
Wiener model with a sigmoid nonlinearity at the output and a unit gain at the input, use
the following command:
m = nlhw(Data,Orders,,'idSigmoidNetwork');
idUnitGain object to exclude specific input and output channels
from being affected by a nonlinearity in Hammerstein-Wiener models.
idUnitGain is a linear function , where F(x)=x.
idnlhwmapping object names is not recommended.
Not recommended starting in R2021b
Starting in R2021b, the mapping objects (also known as nonlinearities) used in the nonlinear components of the
idnlhw objects have been renamed. The following table lists the name changes.
|Pre-R2021b Name||R2021b Name|
Scripts with the old names still run normally, although they will produce a warning. Consider using the new names for continuing compatibility with newly developed features and algorithms. There are no plans to exclude the use of these object names at this time