Pandas DataFrame: Change the order of a DataFrame columns

Last update on December 21 2024 07:41:58 (UTC/GMT +8 hours)

Write a Pandas program to change the order of a DataFrame columns.

Sample data:
Original DataFrame
col1 col2 col3
0 1 4 7
1 4 5 8
2 3 6 9
3 4 7 0
4 5 8 1
After altering col1 and col3
col3 col2 col1
0 7 4 1
1 8 5 4
2 9 6 3
3 0 7 4
4 1 8 5

Sample Solution :

Python Code :

import pandas as pd
import numpy as np
d = {'col1': [1, 4, 3, 4, 5], 'col2': [4, 5, 6, 7, 8], 'col3': [7, 8, 9, 0, 1]}
df = pd.DataFrame(data=d)
print("Original DataFrame")
print(df)
print('After altering col1 and col3')
df = df[['col3', 'col2', 'col1']]
print(df)

Sample Output:

 Original DataFrame
   col1  col2  col3
0     1     4     7
1     4     5     8
2     3     6     9
3     4     7     0
4     5     8     1
After altering col1 and col3
   col3  col2  col1
0     7     4     1
1     8     5     4
2     9     6     3
3     0     7     4
4     1     8     5                 

Explanation:

The said code creates a Pandas DataFrame called ‘df’ with three columns labeled 'col1', 'col2', and 'col3' and five rows of data.

df = df[['col3', 'col2', 'col1']]: This code reorders the columns of ‘df’ using double brackets, [['col3', 'col2', 'col1']], to select the columns in the order 'col3', 'col2', and 'col1'. The resulting DataFrame, which has the same data as the original ‘df’ but with columns in a different order, is stored back into the ‘df’ variable.

Python-Pandas Code Editor:

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