Python : How to Sort a list of strings ? | list.sort()

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How to sort a list of strings using list.sort() in python ?

In this article we will discuss about 4 different ways of sorting a list of strings.

In python, list is a versatile data type which stores multiple elements in a single variable without caring about the types of data.

Syntax : my_list = [element1, element2, element3]

The 4 ways are

  1. By Alphabetical Order
  2. By Reverse Alphabetical Order
  3. By String Length
  4. By Numeric Order

List provides a sort() method by using which we can sort the elements of list from lower order to higher order.

So, let’s start exploring the topic.

Method-1 : By Alphabetical Order

Let’s see a program how it sorts in alphabetical order.

#Program :

#List Of Strings
my_list = ['bat' , 'ant', 'cat', 'eye', 'dog']
my_list.sort()
print(my_list)

Output :
['ant' , 'bat', 'cat', 'dog', 'eye']

Method-2 : By Reverse Alphabetical Order

Let’s see a program how it sorts in alphabetical order.

#Program :

#List Of Strings
my_list = ['bat' , 'ant', 'cat', 'eye', 'dog']
my_list.sort(reverse=True)
print(my_list)

Output :
['eye' , 'do', 'cat', 'bat', 'ant']

Here, sort() method accepts another argument reverse, and it it is True then it sorts the element. Default value is False. When set True, it sorts element in reverse order.

Method-3 : By String Length

Let’s see a program how it sorts in alphabetical order.

#Program :

#List Of Strings
my_list = ['apple' , 'ant', 'aeroplane', 'auto', 'a']
my_list.sort(key=len)
print(my_list)

Output :
['a' , 'ant',  'auto', 'apple', 'aeroplane']

Here, sort() method accepts another argument i.e key. During sorting each element of list will be compared with each other.

Syntax : list.sort(key=function)

Here we have passed len() function as key function. And all the element are sorted as per string length.

Method-4 : By Numeric Order

Suppose we have a list of strings, where each element are of numbers. There we can use int() as key function.

Let’s see a program how it sorts in alphabetical order.

#Program : 

#List Of Strings 
my_list = ['4' , '6', '1', '3', '2'] 
my_list.sort(key=int) 
print(my_list)

Output :
['1','2','3','4','6']