.Modelica_LinearSystems2.TransferFunction.Analysis.evaluate

Information

Syntax

result = TransferFunction.Analysis.evaluate(tf, s)

Description

Function Analysis.evaluate evaluates a transfer function at a given (complex) value of s. The transfer function G(s)=N(s)/D(s) is evaluated by calculating the numerator polynomial N(s) and the denominator polynomial D(s).

Example

  import Modelica.ComplexMath.j;
  TransferFunction s = Modelica_LinearSystems2.TransferFunction.s();
  Modelica_LinearSystems2.TransferFunction tf=(s+1)/(s^2+s+1);

  Complex result;

algorithm
  result := Modelica_LinearSystems2.TransferFunction.Analysis.evaluate(tf, j+1);
//  result = 0.538462 - 0.307692*j

See also

Math.Polynomial.evaluateComplex

Interface

encapsulated function evaluate
  import Modelica;
  import Modelica.ComplexMath.j;
  import Complex;
  import Modelica_LinearSystems2.Math.Polynomial;
  import Modelica_LinearSystems2.TransferFunction;
  input TransferFunction tf "transfer function of a system";
  input Complex s "Value of s where tf shall be evaluated";
  input Real den_min = 0 "|denominator(s)| is limited by den_min";
  output Complex result "= tf(s)";
end evaluate;