Python 3.x 按特定ID列查找两个整数列之间的差异

我有以下两个数据帧

最后的请求：

name    fruit_id  sold
apple   123       1 
melon   456       12
banana  12        23

name    fruit_id  sold
apple   123       5 
melon   456       19
banana  12        43
orange  55        3 
mango   66        0 

当前_请求_df：

name    fruit_id  sold
apple   123       1 
melon   456       12
banana  12        23

name    fruit_id  sold
apple   123       5 
melon   456       19
banana  12        43
orange  55        3 
mango   66        0 

输出应基于匹配上一个请求和当前请求的水果id列，并计算已售出列中的差异：

差异_df：

name    fruit_id  sold
apple   123       4 
melon   456       7
banana  12        20
orange  55        3 
mango   66        0

我尝试了以下方法，但恐怕fruid\U id列不匹配

difference_df['sold_diff'] = current_request_df['sold'] - last_request_df['sold'] 

---

根据我提供的数据，是否有更好的方法来捕捉差异？

是的，谢谢。。。这解决了我一直在寻找的问题。有时很难找到你想要解决的确切问题。谢谢你指出这一点！

 #Reset index to name for both dfs

 difference_df=current_request_df.set_index('name')
 last_request_df=last_request_df.set_index('name')
     

#Find the difference using sub. To do this ensure the two dfs have same index by reindexing 

difference_df['sold']=difference_df['sold'].sub(last_request_df.reindex(index=difference_df.index).fillna(0)['sold'])
    

  

         fruit_id  sold
name                  
apple        123   4.0
melon        456   7.0
banana        12  20.0
orange        55   3.0
mango         66   0.0