What Is Numpy Broadcasting ?

Table Of Contents:

  1. What Is Broadcasting ?
  2. Examples Of Broadcasting.

(1) What Is Broadcasting ?

  • The term broadcasting describes how NumPy treats arrays with different shapes during arithmetic operations
  • Subject to certain constraints, the smaller array is “broadcast” across the larger array so that they have compatible shapes.

(2) Examples Of Broadcasting ?

Example-1:

import numpy as np
data = np.array([1.0, 2.0])
data * 1.6

Output:

array([1.6, 3.2])

Example-2:

a = np.array([[ 0.0,  0.0,  0.0],
              [10.0, 10.0, 10.0],
              [20.0, 20.0, 20.0],
              [30.0, 30.0, 30.0]])
b = np.array([1.0, 2.0, 3.0])
a + b

Output:

array([[ 1.,  2.,  3.],
       [11., 12., 13.],
       [21., 22., 23.],
       [31., 32., 33.]])

Example-3:

a = np.array([[ 0.0,  0.0,  0.0],
              [10.0, 10.0, 10.0],
              [20.0, 20.0, 20.0],
              [30.0, 30.0, 30.0]])
b = np.array([1.0, 2.0, 3.0, 4.0])
a + b

Output:

ValueError                                Traceback (most recent call last)
Input In [39], in <cell line: 6>()
      1 a = np.array([[ 0.0,  0.0,  0.0],
      2               [10.0, 10.0, 10.0],
      3               [20.0, 20.0, 20.0],
      4               [30.0, 30.0, 30.0]])
      5 b = np.array([1.0, 2.0, 3.0, 4.0])
----> 6 a + b

ValueError: operands could not be broadcast together with shapes (4,3) (4,) 

Leave a Reply

Your email address will not be published. Required fields are marked *