How to classify the same index-CodePudding

I have two pandas.DataFrame of the form

Two data frames are:

df1 = pd.DataFrame(4*[100,100,100],4*[0,1,2])
df2 = pd.DataFrame([1,2,3,4,5,6,7,8,9],[0,1,2,0,1,0,2,1,2])

I want to classify df1 and df2 with the same index based on the index of df1. And I want to put 0 in the blank. Here is my expected result:

index     df1       df2

0         100       1
1         100       2
2         100       3
0         100       4
1         100       5
2         100       0
0         100       6
1         100       0
2         100       7
0         100       0
1         100       8
2         100       9

Is this possible?

CodePudding user response：

I think what you are looking for is pandas.DataFrame.sort_values

check sort_values for reference.

CodePudding user response：

If you don't mind with index, such as this kind of format, :

Int64Index([0, 0, 0, 1, 1, 1, 2, 2, 2], dtype='int64')

You can try this :

new_df = pd.merge(df1, df2, left_index=True, right_index=True, how='right').drop_duplicates()
new_df.rename(columns={'0_x' : 'df1',
                       '0_y' : 'df2'})

It will give you :

   df1  df2
0  100    1
0  100    4
0  100    6
1  100    2
1  100    5
1  100    8
2  100    3
2  100    7
2  100    9