Python 注意事项
- list 和 numpy.arr与常数乘积的结果不同
arr= [1,2,3]
print(arr*5) # [1,2,3,1,2,3,1,2,3,1,2,3,1,2,3]
b=np.array(arr)*5
print(b) # [5,10,15]
arr= [1,2,3]
print(arr*5) # [1,2,3,1,2,3,1,2,3,1,2,3,1,2,3]
b=np.array(arr)*5
print(b) # [5,10,15]
