创建代表二维点的 class

Question

实现一个 class 表示 2D 点（即具有 x 和 y 位置的点）实现以下方法： distanceFromOrigin()：计算并 returns 到 Point2D(0,0) 的距离。

#this code
#p = Point2D(3,4)
#print(p.distanceFromOrigin())
#shall produce the following output
#5.0

import math

class Point2D:  
  def disctanceFromOrigin():
    dist = math.sqrt((x2 - x1)**2 + (y2 - y1)**2)
    return dist

p = Point2D(3,4)
print(p.distanceFromOrigin())

有人能告诉我为什么这不起作用吗？ 它返回一个 TypeError: object() takes no parameters

Answer 1

import math

class Point2D:  
  def __init__(self, x, y):
      self.x = x
      self.y = y

  def disctanceFromOrigin(self):
    origin = Point2D(0, 0)
    dist = self.distanceFromPoint(self, origin)
    return dist
  
  def distanceFromPoint(self, point):
    return  math.sqrt((self.x - point.x)**2 + (self.y - point.y)**2


p = Point2D(3,4)
print(p.distanceFromOrigin())