pandas对指定列进行填充

>>> import pandas as pd>>> import numpy as np>>> 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)>>> df     X    Y    Z0  0.0  0.0  0.01  1.0  2.0  2.02  NaN  NaN  NaN3  NaN  3.0  3.04  NaN  NaN  NaN5  NaN  NaN  NaN>>> col =['X','Y']>>> df[col] = df[col].ffill()>>> df     X    Y    Z0  0.0  0.0  0.01  1.0  2.0  2.02  1.0  2.0  NaN3  1.0  3.0  3.04  1.0  3.0  NaN5  1.0  3.0  NaN>>>