day17-object-oriented homework

1. Define a rectangle class with attributes: length and width. Methods: find perimeter and area

   class Rectangle:
       def __init__(self, length=0, wide=0):
           self.length = length
           self.wide = wide
   
       def perimeter(self):
           return (self.length+self.wide)*2
   
       def acreage(self):
           return self.length*self.wide
   
   
   r1 = Rectangle(4, 5)
   print(r1.perimeter(), r1.acreage())
   

2. Define a two-dimensional point class with attributes: x-coordinate and y-coordinate. Method: find the distance from the current point to another point

   class Piont:
       def __init__(self, x=0, y=0):
           self.x = x
           self.y = y
   
       def p_to_p_length(self, point):
           return ((self.x-point.x)**2+(self.y-point.y)**2)**0.5
   
   
   p1 = Piont(2, 5)
   p2 = Piont(-1, 1)
   print(p1.p_to_p_length(p2))
   

3. Define a circle class with attributes: radius and center. Methods: find the circumference and area of ​​the circle, determine whether the current circle is circumscribed to another circle

   import math
   
   
   class Point:
       def __init__(self, x=0, y=0):
           self.x = x
           self.y = y
   
       def p_to_p_length(self, point):
           return ((self.x-point.x)**2+(self.y-point.y)**2)**0.5
   
   
   class Circle:
       def __init__(self, radius=0, center=Point(0, 0)):
           self.radius = radius
           self.center = center
   
       def perimeter(self):
           return 2*math.pi*self.radius
   
       def acreage(self):
           return self.radius**2*math.pi
   
       def exterior_contact(self, another):
           return self.radius+another.radius == self.center.p_to_p_length(another.center)
   
   
   c1 = Circle(1, Point(0, 0))
   c2 = Circle(4, Point(3, 4))
   print(c1.perimeter(), c1.acreage(), c1.exterior_contact(c2))
   

4. Define a line segment class, with attributes: start point and end point, and method: get the length of the line segment

   class Point:
       def __init__(self, x=0, y=0):
           self.x = x
           self.y = y
   
       def p_to_p_length(self, point):
           return ((self.x-point.x)**2+(self.y-point.y)**2)**0.5
   
   
   class Line:
       def __init__(self, start: Point, end: Point):
           self.start = start
           self.end = end
   
       def length(self):
           return self.start.p_to_p_length(self.end)
   
   
   l1 = Line(Point(0, 0), Point(3, 4))
   print(l1.length())
   

5. Define a dog and a human:

   Dog has attributes: name, gender and breed. Method of possession: call

   Human possessing attributes: name, age, dog possessing method: walking the dog

   class Human:
       def __init__(self, name: str, age: int, dog=None):
           self.name = name
           self.age = age
           self.dog = dog
   
       def walk_the_dog(self):
           if self.dog:
               return f'{self.name}遛{self.dog.breed}品种的{self.dog.name}'
   
   
   class Dog:
       def __init__(self, name: str, gender: str, breed: str):
           self.name = name
           self.gender = gender
           self.breed = breed
   
       def call_out(self):
           return f'{self.name}叫唤'
   
   
   dog1 = Dog('阿黄', '雌', '疯狗')
   person1 = Human('黄哥', 18, dog1)
   print(dog1.call_out(), person1.walk_the_dog())
   

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