H_DASHREPLACE_WITH_DASH_DASHREPLACE_WITH_DASH_DASHREPLACE_WITH_DASH_DASHREPLACE_WITH_DASH_DASH
        % Compute the derivative of the gas density wrt to the gas pressure
        function drhogdpg = derivativeGasDensityWrtGasPressure(this,rhog,pg)
            % Pertubation value
            pert = sqrt(eps);
            % Compute the gas density given a pertubation at the gas pressure
            rhogPert = this.gasFluid.getDensity(pg + pert);
            % Compute the derivative
            drhogdpg = (rho