def direction_cosine(self, point):
        """
        Gives the direction cosine between 2 points

        Parameters
        ==========

        p : Point3D

        Returns
        =======

        list

        Examples
        ========

        >>> from sympy import Point3D
        >>> p1 = Point3D(1, 2, 3)
        >>> p1.direction_cosine(Point3D(2, 3, 5))
        [sqrt(6)/6, sqrt(6)/6, sqrt(6)/3]
        """
        a = self.direction_ratio(point)
        b = sqrt(sum(i**2 for i in a))
        return [b / (point.x - self.x),(point.y - self.y) / b,
                (point.z - self.z) / b]
dataset/ETHPy150Open sympy/sympy/sympy/geometry/point.py/Point3D.direction_cosine/swapped operands of `/`