如何将2个Excel与熊猫合并

时间:2020-05-15 09:31:52

标签: python pandas dataframe

我有两个要合并的Excel文件:

file1        file2
   a   b        a     b
1  AA  aa    1  AA   aaaa
2  BB  bb    2  BB   bbbb
3  CC  cc    3  CC   cccc
4  DD  dd
5  EE  ee

具有:

all_data_st = pd.merge( file1, file2, on="Unique")

我能够合并并接收:

 file3
   a     b   c
1  AA   aa   aaaa
2  BB   bb   bbbb
3  CC   cc   cccc

但是,我想收到:

 file4
   a     b   c
1  AA   aa   aaaa
2  BB   bb   bbbb
3  CC   cc   cccc
4  DD   dd
5  EE   ee

请告知公式。谢谢

1 个答案:

答案 0 :(得分:1)

将您的数据框视为

file1 = pd.DataFrame({"a": ["AA", "BB", "CC", "DD", "EE"], "b": ["aa", "bb", "cc", "dd", "ee"]})
file2 = pd.DataFrame({"a": ["AA", "BB", "CC"], "b": ["aaaa", "bbbb", "cccc"]})

使用:

all_data_st = (
    pd.merge(file1, file2, on="a", how="left")
    .fillna('').rename(columns={"b_x": "b", "b_y": "c"}))

print(all_data_st)

结果:

    a   b     c
0  AA  aa  aaaa
1  BB  bb  bbbb
2  CC  cc  cccc
3  DD  dd      
4  EE  ee