.MultiPhaseMixture.PreDefined.Mixtures.NativeModelica.DryAir.EquationsOfState.AirFastIdealGas.T_psX.Internal.f_nonlinear .MultiPhaseMixture.PreDefined.Mixtures.NativeModelica.DryAir.EquationsOfState.AirFastIdealGas.T_psX.Internal.f_nonlinearnote that this function always sees the complete mass fraction vector