Python: Sort a given list of tuples on specified element

Last update on February 22 2025 10:55:44 (UTC/GMT +8 hours)

Sort Tuples by Specified Element

Write a Python program to sort a given list of tuples by a specified element.

Visual Presentation:

Sample Solution:

Python Code:

# Define a function called 'sort_on_specific_item' that sorts a list of tuples based on a specific element of each tuple.
def sort_on_specific_item(lst, n):
    # Sort the list 'lst' based on the element at index 'n' of each tuple.
    result = sorted(lst, key=lambda x: x[n])
    return result
	
# Create a list of tuples 'items', where each tuple contains items with three elements.
items = [('item2', 10, 10.12), ('item3', 15, 25.10), ('item1', 11, 24.50), ('item4', 12, 22.50)]

# Print a message indicating the original list of tuples.
print("Original list of tuples:")
# Print the original list 'items'.
print(items)

# Print a message indicating sorting based on the 1st element (index 0) of the tuple in the list.
print("\nSort on 1st element of the tuple of the said list:")
# Call the 'sort_on_specific_item' function with 'items' and index '0' for the 1st element.
n = 0
# Print the result of the sorting.
print(sort_on_specific_item(items, n))

# Print a message indicating sorting based on the 2nd element (index 1) of the tuple in the list.
print("\nSort on 2nd element of the tuple of the said list:")
# Call the 'sort_on_specific_item' function with 'items' and index '1' for the 2nd element.
n = 1
# Print the result of the sorting.
print(sort_on_specific_item(items, n))

# Print a message indicating sorting based on the 3rd element (index 2) of the tuple in the list.
print("\nSort on 3rd element of the tuple of the said list:")
# Call the 'sort_on_specific_item' function with 'items' and index '2' for the 3rd element.
n = 2
# Print the result of the sorting.
print(sort_on_specific_item(items, n)) 

Sample Output:

Original list of tuples:
[('item2', 10, 10.12), ('item3', 15, 25.1), ('item1', 11, 24.5), ('item4', 12, 22.5)]

Sort on 1st element of the tuple of the said list:
[('item1', 11, 24.5), ('item2', 10, 10.12), ('item3', 15, 25.1), ('item4', 12, 22.5)]

Sort on 2nd element of the tuple of the said list:
[('item2', 10, 10.12), ('item1', 11, 24.5), ('item4', 12, 22.5), ('item3', 15, 25.1)]

Sort on 3rd element of the tuple of the said list:
[('item2', 10, 10.12), ('item4', 12, 22.5), ('item1', 11, 24.5), ('item3', 15, 25.1)]

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to sort a list of tuples by the last element in each tuple.
• Write a Python program to sort a list of tuples based on the sum of their elements.
• Write a Python program to sort a list of tuples by a specified element in descending order.
• Write a Python program to sort a list of tuples using a custom function applied to a specified element.

Python Code Editor:

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