Pandas: Convert into specified number of columns from multi levels index

Last update on May 28 2022 13:02:57 (UTC/GMT +8 hours)

Pandas Indexing: Exercise-10 with Solution

Write a Pandas program to convert 1^st and 3^rd levels in the index into columns from a multiple level of index frame of a given dataframe.

Test Data:

0        s001     V  Alberto Franco     15/05/2002      35  street1   t1
1        s002     V    Gino Mcneill     17/05/2002      32  street2   t2
2        s003    VI     Ryan Parkes     16/02/1999      33  street3   t3
3        s001    VI    Eesha Hinton     25/09/1998      30  street1   t4
4        s002     V    Gino Mcneill     11/05/2002      31  street2   t5
5        s004    VI    David Parkes     15/09/1997      32  street4   t6

Sample Solution:

Python Code :

import pandas as pd
df = pd.DataFrame({
    'school_code': ['s001','s002','s003','s001','s002','s004'],
    'class': ['V', 'V', 'VI', 'VI', 'V', 'VI'],
    'name': ['Alberto Franco','Gino Mcneill','Ryan Parkes', 'Eesha Hinton', 'Gino Mcneill', 'David Parkes'],
    'date_of_birth': ['15/05/2002','17/05/2002','16/02/1999','25/09/1998','11/05/2002','15/09/1997'],
    'weight': [35, 32, 33, 30, 31, 32],
    't_id': ['t1', 't2', 't3', 't4', 't5', 't6']})
print("Original DataFrame:")
print(df)
print("\nMultiIndex using columns 't_id', ‘school_code’ and 'class':")
df1 = df.set_index(['t_id', 'school_code', 'class'])
print(df1)
print("\nConvert 1st and 3rd levels in the index frame into columns:")
df2 = df1.reset_index(level=['t_id', 'class'])
print(df2)

Sample Output:

Original DataFrame:
  school_code class            name date_of_birth  weight t_id
0        s001     V  Alberto Franco    15/05/2002      35   t1
1        s002     V    Gino Mcneill    17/05/2002      32   t2
2        s003    VI     Ryan Parkes    16/02/1999      33   t3
3        s001    VI    Eesha Hinton    25/09/1998      30   t4
4        s002     V    Gino Mcneill    11/05/2002      31   t5
5        s004    VI    David Parkes    15/09/1997      32   t6

MultiIndex using columns 't_id', ‘school_code’ and 'class':
                                  name date_of_birth  weight
t_id school_code class                                      
t1   s001        V      Alberto Franco    15/05/2002      35
t2   s002        V        Gino Mcneill    17/05/2002      32
t3   s003        VI        Ryan Parkes    16/02/1999      33
t4   s001        VI       Eesha Hinton    25/09/1998      30
t5   s002        V        Gino Mcneill    11/05/2002      31
t6   s004        VI       David Parkes    15/09/1997      32

Convert 1st and 3rd levels in the index frame into columns:
            t_id class            name date_of_birth  weight
school_code                                                 
s001          t1     V  Alberto Franco    15/05/2002      35
s002          t2     V    Gino Mcneill    17/05/2002      32
s003          t3    VI     Ryan Parkes    16/02/1999      33
s001          t4    VI    Eesha Hinton    25/09/1998      30
s002          t5     V    Gino Mcneill    11/05/2002      31
s004          t6    VI    David Parkes    15/09/1997      32

Python Code Editor:

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