Convert Pandas Column to List

In data analysis and manipulation, we often need to convert a column of a dataframe to a list. For example, getting column values as a list to use it in some other function or to perform some operations on it.

In this article, we will look at multiple different ways to convert a column of a dataframe to a list.

    Table of Contents

  1. Using tolist() Method
  2. Converting via values Attribute
  3. List Comprehension Approach
  4. Using tolist() with Specific Column Selection
  5. Conclusion

1. Using tolist() Method

To list method is a built-in method in pandas that convert a given column of dataframe to a list.

First access the column you want to convert to a list and then call the tolist() method on it.

import pandas as pd

# Sample DataFrame
data = {'Name': ['Alice', 'Bob', 'Charlie'],
        'Age': [25, 30, 35]}

df = pd.DataFrame(data)

# 👇 Converting 'Name' column to a list
name_list = df['Name'].tolist()

print(name_list)

Output:

['Alice', 'Bob', 'Charlie']

2. Converting via values Attribute

An alternative method involves using the values attribute of the Pandas Series, which returns a NumPy array. You can then convert this array to a Python list.

import pandas as pd

# Sample DataFrame
data = {'Name': ['Alice', 'Bob', 'Charlie'],
        'Age': [25, 30, 35]}

df = pd.DataFrame(data)

# 👇 Converting 'Name' column to a list
name_list = df['Name'].values.tolist()

print(name_list)

Output:

['Alice', 'Bob', 'Charlie']

3. List Comprehension Approach

List comprehension is a quick way to create list in Python. To convert a column of a dataframe to a list, we can use list comprehension.

Here is how we can do it:

import pandas as pd

# Sample DataFrame
data = {'Name': ['Alice', 'Bob', 'Charlie'],
        'Age': [25, 30, 35]}

df = pd.DataFrame(data)

# 👇 Converting 'Name' column to a list
name_list = [name for name in df['Name']]

print(name_list)

Output:

['Alice', 'Bob', 'Charlie']

4. Using tolist() with Specific Column Selection

If you have multiple columns and want to convert a specific one, you can use the iloc or loc indexer along with tolist().

import pandas as pd

# Sample DataFrame
data = {'Name': ['Alice', 'Bob', 'Charlie'],
        'Age': [25, 30, 35],
        'City': ['New York', 'San Francisco', 'Los Angeles']}

df = pd.DataFrame(data)

# 👇 Converting 'City' column to a list using iloc
city_list = df.iloc[:, 2].tolist()

print(city_list)

Output:

['New York', 'San Francisco', 'Los Angeles']

Conclusion

Now you know how to convert a column of a dataframe to a list in Python and you can choose the method that suits your needs.

Whether it's using the tolist() method directly, utilizing the values attribute, employing list comprehension for a concise approach, or selecting a specific column with iloc or loc, Pandas provides versatile options for converting columns to lists.