lens.py 文件源码

def mass_3(self):
        """
        *astropy.Quantity*

        The mass of the tertiary. Defined as total_mass * epsilon[2].
        An *astropy.Quantity* with mass units. If set as a *float*,
        units are assumed to be solMass.

        Note that if total_mass is defined before mass_3, and there is
        no epsilon corresponding to mass_3, mass_3 is added to the total_mass.

        """
        return self.total_mass * self._epsilon[2]