NonlinearStateSpaceModel

NonlinearStateSpaceModel[{f,g},x,u] represents the model x'(t)f(x(t),u(t)), y(t)g(x(t),u(t)).

NonlinearStateSpaceModel[sys] gives a state-space representation corresponding to the systems model sys. 

NonlinearStateSpaceModel[eqns,{{x1,x10},…},{{u1,u10},…},{g1,…},t] gives the state-space model of the differential equations eqns with dependent variables xi, input variables ui, operating values xi0 and ui0, outputs gi, and independent variable t.

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