Convert Python Nested Lists to Multidimensional NumPy Arrays

Prerequisite: Python List, Numpy ndarray

Both lists and NumPy arrays are inter-convertible. Since NumPy is a fast (High-performance) Python library for performing mathematical operations so it is preferred to work on NumPy arrays rather than nested lists.

Method 1: Using numpy.array().

Approach :

• Import numpy package.
• Initialize the nested list and then use numpy.array() function to convert the list to an array and store it in a different object.
• Display both list and NumPy array and observe the difference.

Below is the implementation.

Python3

# importing numpy library
import numpy

# initializing list
ls = [[1, 7, 0],
       [ 6, 2, 5]]

# converting list to array
ar = numpy.array(ls)

# displaying list
print ( ls)

# displaying array
print ( ar)

Output :

[[1, 7, 0], [6, 2, 5]]
[[1 7 0]
 [6 2 5]]

Method 2: Using numpy.asarray().

Approach :

• Import numpy package.
• Initialize the nested 4-dimensional list and then use numpy.asarray() function to convert the list to the array and store it in a different object.
• Display both list and NumPy array and observe the difference.

Below is the implementation.

Python3

# importing numpy library
import numpy

# initializing list
ls = [[1, 7, 0],[ 6, 2, 5],[ 7, 8, 9],[ 41, 10, 20]]

# converting list to array
ar = numpy.asarray(ls)

# displaying list
print ( ls)

# displaying array
print ( ar)

Output :

[[1, 7, 0], [6, 2, 5], [7, 8, 9], [41, 10, 20]]
[[ 1  7  0]
 [ 6  2  5]
 [ 7  8  9]
 [41 10 20]]