How to insert / transplant columns from one dataframe to another at a certain position?

user_11222963 0
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I have two dataframes:

print(df1)

   A  B  C
0  1  5  9
1  2  6  8
2  3  7  7
3  4  8  6


print(df2)

   D  E  F
0  1  5  9
1  2  6  8
2  3  7  7
3  4  8  6

I want to insert columns D and E from df2 into df1 after column B.

The end result should be like this:


   A  B  D  E  C
0  1  5  1  5  9
1  2  6  2  6  8
2  3  7  3  7  7
3  4  8  4  8  6

I know there's already a solution with the insert method with pandas:

df1.insert(1, "D", df2["D"]) df1.insert(2, "E", df2["E"])

However I would like to insert D and E at the same time. Like "transplant" it into df1, rather than having multiple inserts. (in real life the data to be transplanted is bigger which is why I want to avoid all the inserts)

My dataframes in dict format, so you can use DataFrame.from_dict():


# df1

{'A': {0: 1, 1: 2, 2: 3, 3: 4},
 'B': {0: 5, 1: 6, 2: 7, 3: 8},
 'C': {0: 9, 1: 8, 2: 7, 3: 6}}

# df2

{'D': {0: 1, 1: 2, 2: 3, 3: 4},
 'E': {0: 5, 1: 6, 2: 7, 3: 8},
 'F': {0: 9, 1: 8, 2: 7, 3: 6}}
pandas python
3 Answers

You can slice the dataframe df1 into two parts based on the location of column B, then concat these slices with columns D, E along the columns axis

i = df1.columns.get_loc('B') + 1
pd.concat([df1.iloc[:, :i], df2[['D', 'E']], df1.iloc[:, i:]], axis=1)

   A  B  D  E  C
0  1  5  1  5  9
1  2  6  2  6  8
2  3  7  3  7  7
3  4  8  4  8  6
user_128331660

I think your solution is optimal. Alternatively you can:

df1[["D", "E"]] = df2[["D", "E"]]

and then change the column order

user_107430470 
import pandas as pd

df1 = pd.DataFrame.from_dict({'A': {0: 1, 1: 2, 2: 3, 3: 4},
 'B': {0: 5, 1: 6, 2: 7, 3: 8},
 'C': {0: 9, 1: 8, 2: 7, 3: 6}})

df2 = pd.DataFrame.from_dict({'D': {0: 1, 1: 2, 2: 3, 3: 4},
 'E': {0: 5, 1: 6, 2: 7, 3: 8},
 'F': {0: 9, 1: 8, 2: 7, 3: 6}})

df1.merge(df2[['D', 'E']],on=df1.index)

You can reorder based on your requirement

user_127469580
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