迭代行并加入python

我有这样的主数据集

master = pd.DataFrame({'Channel':['1','1','1','1','1'],'Country':['India','Singapore','Japan','United Kingdom','Austria'],'Product':['X','6','7','X','X']})

user = pd.DataFrame({'User':['101','101','102','102','102','103','103','103','103','103'],'Country':['India','Brazil','India','Brazil','Japan','All','Austria','Japan','Singapore','United Kingdom'],'count':['2','1','3','2','1','1','1','1','1','1']})

和这样的用户表

master = pd.DataFrame({'Channel':['1','1','1','1','1'],'Country':['India','Singapore','Japan','United Kingdom','Austria'],'Product':['X','6','7','X','X']})

user = pd.DataFrame({'User':['101','101','102','102','102','103','103','103','103','103'],'Country':['India','Brazil','India','Brazil','Japan','All','Austria','Japan','Singapore','United Kingdom'],'count':['2','1','3','2','1','1','1','1','1','1']})

我希望主表与每个用户的用户表左连接。对于一个用户，如下所示

   merge_101 = pd.merge(master,user[(user.User=='101')],how='left',on=['Country'])
   merge_102 = pd.merge(master,user[(user.User=='102')],how='left',on=['Country'])
   merge_103 = pd.merge(master,user[(user.User=='103')],how='left',on=['Country'])
   merge_all = pd.concat([merge_101, merge_102,merge_103], ignore_index=True)

如何迭代这里的每个用户我首先过滤数据集，创建另一个数据集，然后附加整个数据集

有没有更好的方法来完成这个任务，比如for循环或任何连接

谢谢你，你需要：

pd.concat([pd.merge(master,user[(user.User==x)],how='left',on=['Country']) for x in list(user['User'].unique())], ignore_index=True)

输出：

    Channel         Country Product User count
0        1           India       X  101     2
1        1       Singapore       6  NaN   NaN
2        1           Japan       7  NaN   NaN
3        1  United Kingdom       X  NaN   NaN
4        1         Austria       X  NaN   NaN
5        1           India       X  102     3
6        1       Singapore       6  NaN   NaN
7        1           Japan       7  102     1
8        1  United Kingdom       X  NaN   NaN
9        1         Austria       X  NaN   NaN
10       1           India       X  NaN   NaN
11       1       Singapore       6  103     1
12       1           Japan       7  103     1
13       1  United Kingdom       X  103     1
14       1         Austria       X  103     1

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你能复制并粘贴数据帧而不是图像吗？其他人可以简单地复制和使用数据帧来理解问题。另外，您能显示当前输出与预期输出吗？我认为不需要循环。sure将在循环中添加数据帧while@HarvIpan添加了dataframesCan是否显示了预期的输出？您的代码有

Userid

列，但您的数据帧没有

Userid

列。@HarvIpan添加了一些详细信息