tl; dr：
cols = ['X', 'Y']df.loc[:,cols] = df.loc[:,cols].ffill()
我还添加了一个自我包含的示例：
>>> import pandas as pd>>> import numpy as np>>> >>> ## create dataframe... ts1 = [0, 1, np.nan, np.nan, np.nan, np.nan]>>> ts2 = [0, 2, np.nan, 3, np.nan, np.nan]>>> d = {'X': ts1, 'Y': ts2, 'Z': ts2}>>> df = pd.Dataframe(data=d)>>> print(df.head()) X Y Z0 0 0 01 1 2 22 NaN NaN NaN3 NaN 3 34 NaN NaN NaN>>> >>> ## apply forward fill... cols = ['X', 'Y']>>> df.loc[:,cols] = df.loc[:,cols].ffill()>>> print(df.head()) X Y Z0 0 0 01 1 2 22 1 2 NaN3 1 3 34 1 3 NaN
