Unary minus (multiply transfer function by -1)
function negate import Modelica_LinearSystems2.DiscreteZerosAndPoles; input DiscreteZerosAndPoles dzp; output DiscreteZerosAndPoles result(n1 = dzp.n1, n2 = dzp.n2, d1 = dzp.d1, d2 = dzp.d2, k = -dzp.k, Ts = dzp.Ts, method = dzp.method) "= -dzp"; end negate;