python练习：实现判断圆的位置关系

import math
class Circle:
    def __init__(self,x=0,y=0,radius=1.0):
        self.__x=x;
        self.__y=y;
        self.__radius=radius
    def getX(self):
        return self.__x
    def setX(self,x):
        self.__x=x
    def getY(self):
        return self.__y
    def set(self,y):
        self.__y=y
    def getRadius(self):
        return self.__radius
    def setRadius(self,radius):
        self.__radius= radius
    def getArea(self):
        return self.__radius*self.__radius*math.pi
    def getPerimeter(self):
        return 2*self.__radius*math.pi

    def containsPoint(self,x,y):
        DistancePinfang=(self.__x-x)*(self.__x-x)+(self.__y-y)*(self.__y-y)
        pointDistance=math.sqrt(DistancePinfang)
        if pointDistance >self.__radius:
            return False
        else:
            return True

# 判断依据:设两个圆的半径为R和r,圆心距为d。 则有以下四种关系:
# 1.d>R+r 两圆外离; 两圆的圆心距离之和大于两圆的半径之和。
# 2.d=R+r 两圆外切; 两圆的圆心距离之和等于两圆的半径之和。
# 3.R+r<d<R+r 两园相交;两圆的圆心距离之和小于两圆的半径之和
# 4.d=R-r 两圆内切; 两圆的圆心距离之和等于两圆的半径之差。
# 5.d<R-r 两圆内含;两圆的圆心距离之和小于两圆的半径之差。

    def __relation(self,other):
        pointDistance= self.containsPoint(other[0],other[1])
        if pointDistance > abs(self.__radius+other[2]):
            return 1
        elif  pointDistance == abs(self.__radius+other[2]):
            return 2
        elif  pointDistance ==abs(self.__radius-other[2]):
            return 4
        elif pointDistance <abs(self.__radius-other[2]):
            return 5
        else:
            return 3

    def contain(self,other):
        if (self.__relation(other) == 5 ):
            return  True
        else:
            return False

    def __getitem__(self, item):
        if item ==0:
            return self.__x
        elif item==1:
            return self.__y
        else:
            return self.__radius

    def overlaps(self,other):
        if (self.__relation(other) == 3 ):
            return  True
        else:
            return False

    def __cmp__(self,other):
        selfArea=self.getArea()
        otherArea=other.getArea()
        if selfArea>otherArea:
            return 1
        elif selfArea==otherArea:
            return 0
        else:
            return -1

    def __lt__(self,other):
        return  self.__cmp__(other)<0
    def __le__(self,other):
        return self.__cmp__(other)<=0
    def __eq__(self,other):
        return self.__cmp__(other)==0
    def __ne__(self,other):
        return self.__cmp__(other)!=0
    def __gt__(self,other):
        return self.__cmp__(other)>0
    def __ge__(self,other):
        return self.__cmp__(other)>=0

def main():
   x1,y1,r1=map(eval,input("Enter x1,y1,radius1:").split(",") )
   c1=Circle(x1,y1,r1)
   x2,y2,r2=map(eval,input("Enter x2,y2,radius2:").split(",") )
   c2=Circle(x2,y2,r2)
   print("Area for c1 is ",c1.getArea())
   print("Perimeter for c1 is ",c1.getPerimeter())
   print("Area for c2 is ",c2.getArea())
   print("Perimeter for c2 is ",c2.getPerimeter())
   print("c1 contains the center of c2?",c1.containsPoint(c2.getX(),c2.getY()))
   print("c1 contains c2?",c1.contain(c2))
   print("c1 overlaps c2?",c1.overlaps(c2))
main()