@property
    def periapsis(self):
        """The periapsis of the ellipse.

        The shortest distance between the focus and the contour.

        Returns
        =======

        periapsis : number

        See Also
        ========

        apoapsis : Returns greatest distance between focus and contour

        Examples
        ========

        >>> from sympy import Point, Ellipse
        >>> p1 = Point(0, 0)
        >>> e1 = Ellipse(p1, 3, 1)
        >>> e1.periapsis
        -2*sqrt(2) + 3

        """
        return self.major * (self.eccentricity - 1)
dataset/ETHPy150Open sympy/sympy/sympy/geometry/ellipse.py/Ellipse.periapsis/swapped operands of `-`