Pandas: Select rows from multi-index dataframe

Last update on December 21 2024 07:53:28 (UTC/GMT +8 hours)

Write a Pandas program to select rows by filtering on one or more column(s) in a multi-index dataframe.

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, 37, 33, 30, 31, 32],
    'tcode': ['t1', 't2', 't3', 't4', 't5', 't6']})    
print("Original DataFrame:")
print(df)
print("\nCreate MultiIndex on 'tcode' and 'school_code':")
df = df.set_index(['tcode', 'school_code'])
print(df)
print("\nSelect rows(s) from 'tcode' column:")
print(df.query("tcode == 't2'"))
print("\nSelect rows(s) from 'school_code' column:")
print(df.query("school_code == 's001'"))
print("\nSelect rows(s) from 'tcode' and 'scode' columns:")
print(df.query(("tcode == 't1'") and ("school_code == 's001'")))

Sample Output:

Original DataFrame:
  school_code class            name date_of_birth  weight tcode
0        s001     V  Alberto Franco    15/05/2002      35    t1
1        s002     V    Gino Mcneill    17/05/2002      37    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

Create MultiIndex on 'tcode' and 'school_code':
                  class            name date_of_birth  weight
tcode school_code                                            
t1    s001            V  Alberto Franco    15/05/2002      35
t2    s002            V    Gino Mcneill    17/05/2002      37
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

Select rows(s) from 'tcode' column:
                  class          name date_of_birth  weight
tcode school_code                                          
t2    s002            V  Gino Mcneill    17/05/2002      37

Select rows(s) from 'school_code' column:
                  class            name date_of_birth  weight
tcode school_code                                            
t1    s001            V  Alberto Franco    15/05/2002      35
t4    s001           VI    Eesha Hinton    25/09/1998      30

Select rows(s) from 'tcode' and 'scode' columns:
                  class            name date_of_birth  weight
tcode school_code                                            
t1    s001            V  Alberto Franco    15/05/2002      35
t4    s001           VI    Eesha Hinton    25/09/1998      30

Python Code Editor:

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