Compute specifc entropy (gas parts only!) of moist gases
function s_pTX input Modelica.SIunits.AbsolutePressure p "Pressure"; input Modelica.SIunits.Temperature T "Temperature"; input Modelica.SIunits.MassFraction X[:] "Mass fractions "; output Modelica.SIunits.SpecificEntropy s "Specific entropy"; end s_pTX;