python易错点

• 列表、数组赋值

a = [1,6]
b = a * 2
b[0] = -9999
print(a)
print(b)

[1, 6]
[-9999, 6, 1, 6]

a = [1,6]
b = a 
b[0] = -9999
print(a)
print(b)
[-9999, 6]
[-9999, 6]

import numpy as np
a = np.array([1,6])
b = a * 2
b[0] = -9999
print(a)
print(b)

[1 6]
[-9999    12]

import numpy as np
a = np.array([1,6])
b = a 
b[0] = -9999
print(a)
print(b)
[-9999     6]
[-9999     6]