from matplotlib import pyplot as plt#导入库
import numpy as np
#生成数据图集
n=1024
X=np.random.normal(0,1,n)
Y=np.random.normal(0,1,n)
T=np.arctan2(Y,X)#color
plt.scatter(X,Y,alpha=.5,s=75,c=T)
plt.xlim((-1.5,1.5))
plt.xticks(())
plt.ylim((-1.5,1.5))
plt.yticks(())
plt.show()