我有两个数据帧，我想使用某种VLOOKUP函数，它将句子与特定关键字匹配。在下面的例子中，（df​​1）3e句子应该与banana（df2）匹配，因为它在句子中包含香蕉。

import pandas as pd

df1 = pd.DataFrame({'Text': ['Some text 1', 'Some text 2','The monkey eats a banana','Some text 4']})

df2 = pd.DataFrame({'Keyword': ['apple', 'banana', 'chicken'], 'Type': ['fruit', 'fruit', 'meat']})

df1

Text

0 Some text 1

1 Some text 2

2 The monkey eats a banana

3 Some text 4

df2

Keyword Type

0 apple fruit

1 banana fruit

2 chicken meat

因此，最好的结果是：

Text Type

0 Some text 1 -

1 Some text 2 -

2 The monkey eats a banana fruit

3 Some text 4

-

解决办法：

使用extract的关键字，并且map图中提取到“关键字”到“类型”。

import re

p = rf"({'|'.join(map(re.escape, df2['Keyword']))})"

# p = '(' + '|'.join(map(re.escape, df2['Keyword'])) + ')'

df1['Type'] = (

df1['Text'].str.extract(p, expand=False).map(df2.set_index('Keyword')['Type']))

df1

Text Type

0 Some text 1 NaN

1 Some text 2 NaN

2 The monkey eats a banana fruit

3 Some text 4 NaN