sort() in Python

Like C++ sort(), Java sort() and other languages, python also provides built in function to sort. The sort function can be used to sort the list in both ascending and descending order. To sort the list in ascending order. Its time complexity is O(NlogN).

Syntax

# This will sort the given list in ascending order. # It returns a sorted list according to the passed parameter. List_name.sort()

This function can be used to sort list of integers, floating point number, string and others. 

Python3

# List of Integers
numbers = [1, 3, 4, 2]

# Sorting list of Integers
numbers.sort()

print(numbers)

# List of Floating point numbers
decimalnumber = [2.01, 2.00, 3.67, 3.28, 1.68]

# Sorting list of Floating point numbers
decimalnumber.sort()

print(decimalnumber)

# List of strings
words = ["Geeks", "For", "Geeks"]

# Sorting list of strings
words.sort()

print(words)

Output:

[1, 2, 3, 4]
[1.68, 2.0, 2.01, 3.28, 3.67]
['For', 'Geeks', 'Geeks']

To sort the list in descending order. 

Syntax

list_name.sort(reverse=True)
This will sort the given list in descending order.

Python3

# List of Integers
numbers = [1, 3, 4, 2]

# Sorting list of Integers
numbers.sort(reverse=True)

print(numbers)

# List of Floating point numbers
decimalnumber = [2.01, 2.00, 3.67, 3.28, 1.68]

# Sorting list of Floating point numbers
decimalnumber.sort(reverse=True)

print(decimalnumber)

# List of strings
words = ["Geeks", "For", "Geeks"]

# Sorting list of strings
words.sort(reverse=True)

print(words)

Output:

[4, 3, 2, 1]
[3.67, 3.28, 2.01, 2.0, 1.68]
['Geeks', 'Geeks', 'For']

Syntax : 

list_name.sort() – it sorts in ascending order list_name.sort(reverse=True) – it sorts in descending order list_name.sort(key=…, reverse=…) – it sorts according to user’s choice

Parameters: By default, sort() doesn’t require any extra parameters. However, it has two optional parameters:

reverse – If true, the list is sorted in descending order key – function that serves as a key for the sort comparison

Python

# Python program to demonstrate sorting by user's
# choice

# function to return the second element of the
# two elements passed as the parameter
def sortSecond(val):
    return val[1]

# list1 to demonstrate the use of sorting
# using second key
list1 = [(1,2),(3,3),(1,1)]

# sorts the array in ascending according to
# second element
list1.sort(key=sortSecond)
print(list1)

# sorts the array in descending according to
# second element
list1.sort(key=sortSecond,reverse=True)
print(list1)

Output:

[(1, 1), (1, 2), (3, 3)]
[(3, 3), (1, 2), (1, 1)]

Please refer Python Sort articles for more Python Sorting articles. Thanks to striver for inputs on this topic.