# Convert List to Set in Python?

How to convert a list to a set in python? Lists and sets both are built-in data types of Python and they can store collections of elements. However, there are some key differences between them hence, sometimes you would be required to convert list to set.

A list is an ordered collection of elements so, we can add, remove, modify, and slicing elements in a list by using its position/index order. It allows duplicate elements. Sets are a collection of unique elements, similar to a list or a tuple, but with some key differences. Sets do not allow duplicates, and you can perform various mathematical operations on sets such as union, intersection, and difference easily.

You can convert a list to a set in python using many ways, for example, by using the `set()`, `for loop`, `set comprehension`, and `dict.fromkeys()` functions. In this article, I will explain how to convert a list to a set in python by using all these methods with examples.

## 1. Quick Examples of Converting List to Set

If you are in a hurry, below are some quick examples of how to convert list to set.

``````
# Quick examples of convert list to set

# Initialize list
lists = [5, 2, 3, 4, 3, 5, 4, 6]

# Example 1: Convert the list to a set using set()
myset = set(lists)
print("Set:", myset)

# Example 2: Convert list to set
# Using for loop
myset = set()
for item in lists:

# Example 3: Convert list to set
# Using set comprehension
myset = {item for item in lists}

# Example 4: Convert list to set
# Using dict.fromkeys() method
myset = set(dict.fromkeys(lists))
``````

## 3. Convert List to Set Using Python set() Method

You can convert the list to a set using the set() built-in function, This function takes the list as an argument and converts it to the set. Note that in this conversion process, if List has any duplicate values they will be removed as Set can have only unique values.

For example, let’s take a list that contains integers and strings and pass it into set() function to convert the list into set. The resulting set contains only the unique elements of the list, in random order. the integer `12` only appears once in the set, even though it appears twice in the original list.

``````
# Initialize list
lists = [12, 32 , 6, 12, "sparkby","examples"]
print("List:", lists)

# Convert the list to a set using set()
myset = set(lists)
print("Set:", myset)
``````

Yields below output.

As you can see, from the above code the list contains a ’12’ integer two times but in our resulting set ’12’ has appeared only one time.

## 4. Convert List to Set Using For Loop

You can also convert a list to a set using a for loop in Python. In this example, first, create a list and an empty set. Then, iterate the given list using for loop, for every iteration, one item from the list is added to the empty set using the add() method.

``````
# Initialize the list & set
lists = [5, 2, 3, 4, 3, 5, 4, 6]
myset = set()
print("List:", lists)

# Convert list to set
# Using for loop
for item in lists:
print("Set:", myset)
``````

Yields below output.

## 5. Convert List to Set Using Set Comprehension

You can use set comprehension to convert a list to a set in Python. set comprehension is a concise way to create a set. Let’s use set comprehension over the given list to convert it to a set with unique random values.

Note that the curly braces `{}` are used to define the `set comprehension`, and the `for loop` inside the braces defines the iteration. The resulting set `myset` will contain only unique elements from the original list,

``````
# Convert list to set
# Using set comprehension
lists = [5, 2, 3, 4, 3, 5, 4, 6]
myset = {item for item in lists}
print("List:", lists)
print("Set:", myset)

# Output:
# List: [5, 2, 3, 4, 3, 5, 4, 6]
# Set: {2, 3, 4, 5, 6}
``````

## 6. Using dict.fromkeys() Method

Alternatively, using the dict.fromkeys() method of dictionary to convert a list to a set. However, it can be simplified by removing the intermediate step of converting the dictionary keys back to a list before creating the set.

``````
# Convert list to set
# Using dict.fromkeys() method
lists = [5, 2, 3, 4, 3, 5, 4, 6]
myset = set(dict.fromkeys(lists))
print(myset)
``````

Yields the same output as above.

## 7. Conclusion

In this article, I have explained convertion of list to set can be done by using the `set()`, `for loop`, `set comprehension`, and `dict.fromkeys()` functions. You can use any of the methods as per your need.

Happy Learning !!

### Malli

I am Mallikarjuna an experienced technical writer with a passion for translating complex Python concepts into clear, concise, and user-friendly documentation. Over the years, I have written hundreds of articles in Pandas, NumPy, Python, and I take pride in my ability to bridge the gap between technical experts and end-users by delivering well-structured, accessible, and informative content. 