List to 2D array Python

Converting a list to a 2D array in Python means transforming a one-dimensional list into a two-dimensional structure where elements are organized in rows and columns.

For example, consider the following list:

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]

Converting this list to a 2D array would result in a structure like this:

[[1, 2, 3],
 [4, 5, 6],
 [7, 8, 9]]

In the resulting 2D array, each inner list represents a row, and the elements within each inner list represent the values in that row. The number of rows and columns in the 2D array depends on how you decide to reshape or organize the elements from the original list.

List to 2D array Python example

To convert a list to a 2D array in Python, you can use various approaches. Here are a few methods using different libraries:

1. Using NumPy

import numpy as np

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
num_rows = 3
num_cols = 3

my_array = np.array(my_list).reshape(num_rows, num_cols)
print(my_array)

2. Using List Comprehension

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
num_rows = 3
num_cols = 3

my_array = [my_list[i:i+num_cols] for i in range(0, len(my_list), num_cols)]
print(my_array)

3. Using a Loop

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
num_rows = 3
num_cols = 3

my_array = []
for i in range(0, len(my_list), num_cols):
    my_array.append(my_list[i:i+num_cols])

print(my_array)

Output:

You can Choose the one that best suits your requirements and the libraries available for your project. You can adjust the num_rows and num_cols variables to create a 2D array of different sizes based on your specific requirements.

Do comment if you have any doubts or suggestions on this Python array topic.

Note: IDE: PyCharm 2021.3.3 (Community Edition)

Windows 10

Python 3.10.1

All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.