Create a 2D Numpy Array and Accessing elements Python

Last Updated On Friday 21st Jan 2022

Import the libraries

	import numpy as np
import matplotlib.pyplot as plt
	

Create a list

	a = [[11, 12, 13], [21, 22, 23], [31, 32, 33]]
	

list to a Numpy Array

	arr = np.array(a)
print(arr)
	
	[
  [11, 12, 13],
  [21, 22, 23],
  [31, 32, 33]
]
	

numpy array dimensions

	print(arr.ndim)
# 2
	

numpy array shape

	print(arr.shape)
# (3, 3)
	

numpy array size

	print(arr.size)
# 9
	

Accessing different elements of a Numpy Array

  • We use the square brackets and the indices corresponding to the element we would like.
	print(arr[1, 2])
# 23
	

Access the element on the first row and first column

	print(arr[0][0])
# 11
	

We can also use slicing in numpy arrays

  • Access the element on the first row and first and second columns
	print(arr[0][0:2])
# [11, 12]