python 随机生成N个坐标，并画随机大小的圆
import matplotlib.pyplot as plt
import numpy as np
# plt.plot(x, y, '+')
# plt.show()
class Circle:
def __init__(self,r1=0,x0=0,y0=0):
self.r = r1
self.x = x0
self.y = y0
# 方法,画圆
def pint(self):
# 创建一个空白窗体
# plt.title('Circle')
# plt.xlabel('x')
# plt.ylabel('y')
# 点的横坐标为a
a = np.arange(x-r,x+r,0.01)
# 点的纵坐标为b
b1 = np.sqrt(np.power(self.r,2)-np.power((a-self.x),2))+self.y
b2 = -np.sqrt(np.power(self.r,2)-np.power((a-self.x),2))+self.y
#plt.plot(a,b1,color='r',linestyle='-')
#plt.plot(a,b2,color='r',linestyle='-')
plt.fill_between(a, b2, b1, facecolor='black')
# plt.scatter(self.x,self.y,c='c',marker='+')
plt.axis([-10,310,-10,310])
# plt.grid(True)
N = 200
X = np.random.rand(1, N)*300
X = X.flatten()
Y = np.random.rand(1, N)*300
Y = Y.flatten()
R = np.random.rand(1, N)*5 + 1
R = R.flatten()
plt.figure(figsize=(5,5))
for (r, x, y) in zip(R, X, Y):
#print(r, x, y)
Circle(r, x, y).pint()
plt.show()
