Python | Get unique values from a list

Given a list, print all the unique numbers in any order.
Examples: 

Input : 10 20 10 30 40 40
Output : 10 20 30 40 

Input : 1 2 1 1 3 4 3 3 5 
Output : 1 2 3 4 5  

Method 1 : Traversal of list

Using traversal, we can traverse for every element in the list and check if the element is in the unique_list already if it is not over there, then we can append it in the unique_list. This is done using one for loop and other if statement which check if the value is in the unique list or not which is equivalent to another for loop.  

Output: 

the unique values from 1st list is
10 20 30 40 
the unique values from 2nd list is
1 2 3 4 5

Method 2 : Using Set

Using set() property of Python, we can easily check for the unique values. Insert the values of the list in a set. Set only stores a value once even if it is inserted more then once. After inserting all the values in the set by list_set=set(list1), convert this set to a list to print it. 

Output: 

the unique values from 1st list is
40 10 20 30 
the unique values from 2nd list is
1 2 3 4 5

Method 3 : Using numpy.unique

Using Python’s import numpy, the unique elements in the array are also obtained. In first step convert the list to x=numpy.array(list) and then use numpy.unique(x) function to get the unique values from the list. numpy.unique() returns only the unique values in the list. 

Output 
 

the unique values from 1st list is
[10 20 30 40]

the unique values from 2nd list is
[1 2 3 4 5]

Method #4: Using collections.Counter()

Using python import Counter() from collections print all the keys of Counter elements or we print directly by using “*” symbol.

Below is the implementation of above approach.

Output:

the unique values from 1st list is
10 20 30 40

the unique values from 2nd list is
1 2 3 4 5