returns specific entropy for a given p and T
function specificEntropy_pTX extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input Temperature T "Temperature"; input MassFraction X[nX] "Mass fractions"; input Integer phase = 1 "2 for two-phase, 1 for one-phase, 0 if not known"; output SpecificEntropy s "Specific Entropy"; end specificEntropy_pTX;