python3 AttributeError：'list'对象没有属性'dot'

Question

#unit vector
def normalized(self):
    try:
        unit = [ x/self.magnitude() for x in self.coordinates ]
        return unit
    except ZeroDivisionError:
        raise Exception("Can not normalize the zero vector")

#dot product of vector
def dot(self, v):
    x = [ x*y for x,y in zip(self.coordinates, v.coordinates)]
    return sum(x)

#radians and angle of vector
def angle_with(self, v , degrees = False):
    try:
        u1 = self.normalized()
        u2 = v.normalized()
        print(u1, u2)
        angle_in_radians = math.acos(u1.dot(u2))

        if degrees:
            degrees_per_radian = 180. / math.pi
            return angle_in_radians * degrees_per_radian
        else:
            return angle_in_radians

如何在这里使用“点”功能？

Answer 1

试试这个

class Vector(object):
def __init__(self, coordinates):
        self.coordinates = tuple(coordinates)
        self.dimension = len(coordinates)

def normalized(self):
    try:
        a = 1.0/self.magnitude()
        res = [a*x for x in self.coordinates]
        return res
    except ZeroDivisionError:
        raise Exception('your error messsage')

def dot(self, v):
    return sum([x * y for x,y in zip(self.coordinates,v.coordinates)])

def angle_with(self, v, in_degree=False):
    try:
        u1 = Vector(self.normalized())
        u2 = Vector(v.normalized())
        angle_in_redians = math.acos(u1.dot(u2))

        if in_degree:
            degrees_per_redian = 180. /pi
            return angle_in_redians * degrees_per_redian
        else:
            return angle_in_redians  

OR

#same Vector class and init method
def magnitude(self):
    squared_coordinates = [x**2 for x in self.coordinates]
    return sqrt(sum(squared_coordinates))

def dot(self, v):
    return sum([x * y for x,y in zip(self.coordinates,v.coordinates)])

def angle_with(self, v, in_degree=False):
    try:
        dot = self.dot(v)
        magnitude_v1 = self.magnitude()
        magnitude_v2 = v.magnitude()
        res = dot/(magnitude_v1*magnitude_v2)
        angle_in_redians = math.acos(res)

        if in_degree:
            degrees_per_redian = 180. /pi
            return angle_in_redians * degrees_per_redian
        else:
            return angle_in_redians