Pandas向前向后填充列级中的列

import pandas as pd

# 创建一个示例DataFrame
data = {'A': [1, None, 3, None, 5],
        'B': [None, 2, None, 4, None],
        'C': [None, None, None, None, 6]}
df = pd.DataFrame(data)

# 向前填充列级中的列
df_forward_filled = df.fillna(method='ffill', axis=1)

# 向后填充列级中的列
df_backward_filled = df.fillna(method='bfill', axis=1)

# 打印填充结果
print("向前填充：")
print(df_forward_filled)
print("\n向后填充：")
print(df_backward_filled)

向前填充：
     A    B    C
0  1.0  1.0  1.0
1  NaN  2.0  2.0
2  3.0  3.0  3.0
3  NaN  4.0  4.0
4  5.0  5.0  6.0

向后填充：
     A    B    C
0  1.0  NaN  NaN
1  2.0  2.0  NaN
2  3.0  NaN  NaN
3  4.0  4.0  NaN
4  5.0  NaN  6.0