如何使用Python解决此继承问题?

时间:2019-10-03 13:48:43

标签: python python-3.x oop inheritance python-3.7

在以下用Python编写的脚本中,我想做的是计算圆形,正方形和矩形的面积。其中,我想实现从square.py到rectangle.py的继承。但是,我的继承实现失败,需要一些帮助来解决此问题。

当我尝试计算矩形的面积时,记录了以下错误消息。

int

script.py

Traceback (most recent call last):
  File "script.py", line 28, in <module>
    print(rectangle.sqArea())
  File "/home/yosuke/Dropbox/Coding_dir/Python/Originals/OOP/Mathmatics/testdir2/rectangle.py", line 8, in sqArea
    return self.length * self.height
AttributeError: 'Rectangle' object has no attribute 'length'

circle.py

from circle import Circle
from square import Square
from rectangle import Rectangle

category = {1:"Shapes", 2:"DST"}
    for k,v in category.items():
    print(k, v)
catNum = int(input("Type a category by number>> "))
    if catNum == 1:
        print("You chose shapes")
        shapeDict = {1:"Circle", 2:"Square"}
    for k,v in shapeDict.items():
        print(k, v)
    shapeNum = int(input("Select a shape by number>> "))
    if shapeNum == 1:
        radius = int(input("type a number>> "))
        circle1 = Circle(radius)
        print(circle1.cirArea())

    if shapeNum == 2:
        length = int(input("Type the length>> "))
        square = Square(length)
        print(square.sqArea())

        print("Let's try rectangle too")
        height = int(input("Type the height>> "))
        rectangle = Rectangle(height)
        print(rectangle.sqArea())


    if catNum == 2:
        print("Not yet finished!")

square.py

class Circle:
    def __init__(self, radius):
        self.radius = radius

    def cirArea(self):
        return self.radius * self.radius * 3.14

rectangle.py

class Square:
    def __init__(self, length):
        self.length = length

    def sqArea(self):
        return self.length * self.length

2 个答案:

答案 0 :(得分:0)

您忘记了调用超类的__init__

class Rectangle(Square):
    def __init__(self, height):
        super().__init__(height)

答案 1 :(得分:0)

您的矩形的构造函数仅接收高度,并且仅设置其height属性。没有长度。

在Rectangle中,这样的事情可能起作用:

def __init__(self, length, height):
    super().__init__(length)
    self.height = height

但是您的课程很奇怪。矩形不是正方形,正方形是矩形。因此,如果有的话,继承应该在另一个方向上起作用。

但是我认为您很快就会遇到问题。事实证明,面向对象的编程不能很好地对这类事物进行建模,实际上,不同形状之间没有太多共享之处。