Derivative function of p_dT
function p_dT_der extends Modelica.Icons.Function; input SI.Density d "Density"; input SI.Temperature T "Temperature"; input Common.IF97BaseTwoPhase aux "Auxiliary record"; input Real d_der "Derivative of density"; input Real T_der "Derivative of temperature"; output Real p_der "Derivative of pressure"; end p_dT_der;