Python中的bfill方法

import pandas as pd

data = {'A': [1, 2, None, 4], 'B': [1, None, 3, 4]}
df = pd.DataFrame(data)

df_filled = df.bfill()
print(df_filled)

     A    B
0  1.0  1.0
1  2.0  3.0
2  4.0  3.0
3  4.0  4.0

import numpy as np

arr = np.array([[1, 2, 3], [4, np.nan, 6], [7, 8, np.nan]])
print("原始数组：")
print(arr)

arr_filled = pd.DataFrame(arr).bfill().to_numpy()
print("填充缺失值后的数组：")
print(arr_filled)

原始数组：
[[ 1.  2.  3.]
 [ 4. nan  6.]
 [ 7.  8. nan]]
填充缺失值后的数组：
[[1. 2. 3.]
 [4. 8. 6.]
 [7. 8. 6.]]