def cross(self, v):
        """Cross product of two vectors.

        Parameters
        ----------
        v : CartesianVector
            The vector to take cross product with.

        Returns
        -------
        v : CartesianVector
            Cross product of this vector and the given vector.

        """
        n = self.__class__()
        n.x = self.y * v.z - self.z * v.y
        n.y = - (self.x * v.z - self.z * v.x)
        n.z = self.x * v.y - self.y * v.x

        return n