(Python)Joing Dataframes with simple form-CodePudding

My goal is to join multiple tables and 3 tables can be joined like this as expected.

import pandas as pd
df1 = pd.DataFrame({'A':[10,20,30]}, index=[1,2,3])
df2 = pd.DataFrame({'B':[200]}, index=[2])
df3 = pd.DataFrame({'C':[300]}, index=[3])
df1.join(df2).join(df3)

    A      B     C
1  10    NaN    NaN
2  20  200.0    NaN
3  30    NaN  300.0

However, whenever I join another table, as above, colums of the table are attatched to the right side of the existing one. So, Is there a neat way to join like this simple form? (B and C columns are experessed in one column and the colume name does not matter)

    A      
1  10    NaN
2  20  200.0
3  30  300.0

CodePudding user response：

How about this ?

import pandas as pd

pd.concat([df1,df2, df3], axis=1).set_index('A').sum(axis=1)

A
10      0.0
20    200.0
30    300.0
dtype: float64

CodePudding user response：

Use concat -

df1.join(pd.concat([df2, df3.rename(columns={'C': 'B'})]))
#    A      B
#1  10    NaN
#2  20  200.0
#3  30  300.0