"""
Helper class and functions for basic 3d vector math.
"""

class Vector3(object):
    def __init__(self,*point):
        """Define a vector in 3d space."""
        self.point = point
    def __add__(self,other):
        return map(reduce(lambda a,b: a+b),zip(self.point,other.point))
    def __sub__(self,other):
        return map(reduce(lambda a,b: a-b),zip(self.point,other.point))
    def __mul__(self,other):
        """Scalar multiplication aka the dot product."""
        return map(reduce(lambda a,b: a*b),zip(self.point,other.point))
    def __div__(self,other):
        return map(reduce(lambda a,b: a/b),zip(self.point,other.point))
    @property
    def x(self):
        return point[0]
    @property
    def y(self):
        return point[1]
    @property
    def z(self):
        return point[2]

def cross(a,b):
    """Vector multiplication aka the cross product."""
    x = a.y*b.z - a.z*b.y
    y = a.x*b.z - a.z*b.x
    z = a.x*b.y - a.y*b.x
    return Vector3(x,y,z)

print "Module py.vector3 loaded successfully."