.Modelica_LinearSystems2.WorkInProgress.DiscreteTransferFunction.'constructor'.fromZerosAndPoles

Information

This function constructs a transfer function from numerator zeros. Example:

The transfer function

   zp = (s+(2+3*j))*(s+(2-3*j))

can be expressed as

   import Complex;
   import Modelica_LinearSystems2.ZerosAndPoles;

   j = Complex.j();
   zp = ZerosAndPoles({2+3*j}, {2-3*j});

Since only transfer functions with real coefficients are supported, complex zeros must be defined as conjugate complex pairs. It is required that complex conjugate pairs must directly follow each other as above. An error occurs if this is not the case.

Interface

encapsulated function fromZerosAndPoles
  import Modelica;
  import Complex;
  import Modelica_LinearSystems2;
  import Modelica_LinearSystems2.WorkInProgress.DiscreteTransferFunction;
  import Modelica_LinearSystems2.Math.Polynomial;
  input Complex z[:] = fill(Complex(0), 0) "Zeros (Complex vector of numerator zeros)";
  input Complex p[:] = fill(Complex(0), 0) "Poles (Complex vector of denominator zeros)";
  input Real k = 1.0 "Constant multiplied with transfer function";
  input Modelica.Units.SI.Time Ts "Sample time";
  input Modelica_LinearSystems2.Utilities.Types.Method method = Modelica_LinearSystems2.Utilities.Types.Method.Trapezoidal "Discretization method";
  input String uName = "" "input name";
  input String yName = "" "output name";
  output DiscreteTransferFunction dtf(redeclare Real n[size(z, 1) + 1], redeclare Real d[size(p, 1) + 1]) "TransferFunction built by ZerosAndPoles object";
end fromZerosAndPoles;