Python: Sort a list of lists by a given index of the inner list using lambda

Last update on April 22 2025 12:51:58 (UTC/GMT +8 hours)

37. Sort List by Index Lambda

Write a Python program to sort a list of lists by a given index of the inner list using lambda.

Sample Solution:

Python Code :

# Define a function 'index_on_inner_list' that sorts a list of lists based on a specified index of inner lists
def index_on_inner_list(list_data, index_no):
    # Sort the 'list_data' based on the specified 'index_no' of inner lists using the 'sorted' function
    # The 'key' parameter uses a lambda function to access the element at the given 'index_no'
    result = sorted(list_data, key=lambda x: x[index_no])
    
    # Return the sorted list of lists
    return result

# Create a list of tuples 'students' containing names and two additional elements for each student
students = [
    ('Greyson Fulton', 98, 99),
    ('Brady Kent', 97, 96),
    ('Wyatt Knott', 91, 94),
    ('Beau Turnbull', 94, 98)
]

# Print the original list of tuples 'students'
print("Original list:")
print(students)

# Sort the list of tuples based on the index 0 of the inner lists and print the result
index_no = 0
print("\nSort the said list of lists by a given index", "(Index =", index_no, ") of the inner list")
print(index_on_inner_list(students, index_no))

# Sort the list of tuples based on the index 2 of the inner lists and print the result
index_no = 2
print("\nSort the said list of lists by a given index", "(Index =", index_no, ") of the inner list")
print(index_on_inner_list(students, index_no))

Sample Output:

Original list:
[('Greyson Fulton', 98, 99), ('Brady Kent', 97, 96), ('Wyatt Knott', 91, 94), ('Beau Turnbull', 94, 98)]

Sort the said list of lists by a given index ( Index =  0 ) of the inner list
[('Beau Turnbull', 94, 98), ('Brady Kent', 97, 96), ('Greyson Fulton', 98, 99), ('Wyatt Knott', 91, 94)]

Sort the said list of lists by a given index ( Index =  2 ) of the inner list
[('Wyatt Knott', 91, 94), ('Brady Kent', 97, 96), ('Beau Turnbull', 94, 98), ('Greyson Fulton', 98, 99)]

For more Practice: Solve these Related Problems:

Write a Python program to sort a list of lists by the element at a specified index in each inner list using lambda.
Write a Python program to sort a list of lists by the sum of the elements in the inner list using lambda.
Write a Python program to sort a list of lists by the difference between two specified indices using lambda.
Write a Python program to sort a list of lists by the maximum element in each inner list using lambda.

Go to:

Previous: Write a Python program to extract the nth element from a given list of tuples using lambda.
Next: Write a Python program to remove all elements from a given list present in another list using lambda.

Python Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.