正則表達式PANDAS數據框

Question

我有一個看起來像這樣的數據框：

import pandas as pd

df= pd.DataFrame({'type':['-','L1iability','-','Liability1','-'],'Amount':[10,-10,20,-20,5]})
df

我想用“ 3rd”替換類型列中除“-”以外的所有內容。 我該如何使用replace命令和regex？

Answer 1

IIUC mask

df['3rdcol']=df.type.mask(~(df.type=='-'),'Liability1')
df
Out[303]: 
   Amount        type      3rdcol
0      10           -           -
1     -10  L1iability  Liability1
2      20           -           -
3     -20  Liability1  Liability1
4       5           -           -