如何根据列表有条件地更新Pandas中的DataFrame列

如何根据列表有条件地更新Pandas中的DataFrame列

我认为您可以使用

numpy.where

：

import pandas as pdimport numpy as npdf = pd.Dataframe(np.random.randint(0,9,size=(100, 1)), columns=['number'])df['odd_or_even'] = np.where(df.number % 2, 'odd', 'even')print (df)    number odd_or_even0        1         odd1        0        even2        4        even3        5         odd4        0        even5        0        even6        1         odd7        0        even8        7         odd9        8        even

通过评论编辑

用途

loc

：

import pandas as pdimport numpy as npdf = pd.Dataframe(np.random.randint(0,9,size=(20, 1)), columns=['number'])odd_numbers = [1,3,5,7,9]even_numbers = [0,2,4,6,8]df.loc[df.number.isin(odd_numbers), 'odd_or_even'] = 'odd'df.loc[df.number.isin(even_numbers), 'odd_or_even'] = 'even'print (df)    number odd_or_even0        5         odd1        1         odd2        2        even3        3         odd4        5         odd5        6        even6        3         odd7        4        even8        2        even9        8        even10       8        even11       1         odd12       2        even13       1         odd14       3         odd15       3         odd16       5         odd17       4        even18       2        even19       5         odd