DiscreteInputOutputModel
DiscreteInputOutputModel[{g0,g1,…,gn-1},u] represents a discrete-time model with input u and output y=gi(u) at sampling instant i.
DiscreteInputOutputModel[{g0,g1,…,gn-1},u,y] can be used to specify outputs gi(u,y) that also depend on the output variables y.
DiscreteInputOutputModel[…,{{u1,{…,u10}},…},{{y1,{…,y10}},…}] specifies input and output values for each signal for instants k<=0.
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