'The eccentricity of the ellipse.
Returns
eccentricity : number
Examples
>>> from sympy import Point, Ellipse, sqrt
>>> p1 = Point(0, 0)
>>> e1 = Ellipse(p1, 3, sqrt(2))
>>> e1.eccentricity
sqrt(7)/3'

@property
def eccentricity(self):

    return (self.focus_distance / self.major)
