Python Pandas | Swap levels of a MultiIndex

Python code to swap levels of a MultiIndex

# Import the pandas package
import pandas as pd

# Create arrays
employees = [
        ['E101', 'E102', 'E102', 'E103'],
        ['Alex', 'Alvin', 'Deniel', 'Jenny'],
        [21, 19, 15, 17]
    ]

# create a Multiindex using  from_arrays() 
mi = pd.MultiIndex.from_arrays(employees, names=('emp_ids', 'names', 'age'))

# display the Multiindex
print("The MultiIndex...\n",mi)
print()

# Get the levels in MultiIndex
print("The levels in MultiIndex...\n",mi.levels)
print()

# Swap levels 0 and 1 of a MultiIndex
print("Swap levels...\n",mi.swaplevel(0,1))
print()

# Swap levels 0 and 2 of a MultiIndex
print("Swap levels...\n",mi.swaplevel(0,2))
print()

Output:

The MultiIndex...
 MultiIndex([('E101',   'Alex', 21),
            ('E102',  'Alvin', 19),
            ('E102', 'Deniel', 15),
            ('E103',  'Jenny', 17)],
           names=['emp_ids', 'names', 'age'])

The levels in MultiIndex...
 [['E101', 'E102', 'E103'], ['Alex', 'Alvin', 'Deniel', 'Jenny'], [15, 17, 19, 21]]

Swap levels...
 MultiIndex([(  'Alex', 'E101', 21),
            ( 'Alvin', 'E102', 19),
            ('Deniel', 'E102', 15),
            ( 'Jenny', 'E103', 17)],
           names=['names', 'emp_ids', 'age'])

Swap levels...
 MultiIndex([(21,   'Alex', 'E101'),
            (19,  'Alvin', 'E102'),
            (15, 'Deniel', 'E102'),
            (17,  'Jenny', 'E103')],
           names=['age', 'names', 'emp_ids'])