Machine Learning Prerequisites (Numpy)

You are currently auditing this course.
31 / 32

Numpy - Broadcasting in NumPy Arrays

In any NumPy mathematical operation, if the shape of any of the participating arrays is not sufficient, broadcasting rules come into play.

Broadcasting, generally, tries to adjust the shape of one or both of the arrays to bring them to required matching shape, by copying the existing elements required number of times, so that the mathematical operation could be performed between the two NumPy arrays.

There are two broadcasting rules:

First Rule: If the arrays do not have the same rank, then a 1 will be prepended to the smaller ranking arrays until their ranks match.

Q = np.array( [ [ [1, 3 ] ] ] )
P = np.array( [ 5 ] )

S = Q + P

print(S)

This will print

[ [ [6, 8] ] ]

Second Rule: Arrays with a 1 along with a particular dimension act as if they had the size of the array with the largest shape along that dimension. The value of the array element is repeated along that dimension.

Broadcasting - Second Rule

INSTRUCTIONS

Please follow the below steps:

(1) Please import the required libraries

import numpy as np

(2) Please create a numpy array X_broad of shape (3,3) filled with ones

<<your code comes here>> = np.ones(<<your code comes here>>)

(3) Print array X_broad using print() function to see its values

print(<<your code comes here>>)

(4) Please create a numpy array Y_broad of size 3

Y_broad = np.arange(<<your code comes here>>)

(5) Print array Y_broad using print() function to see its values

print(<<your code comes here>>)

(6) Add X_broad and Y_broad and store the result in a variable Z_broad

<<your code comes here>> = <<your code comes here>>  + <<your code comes here>>

(7) Print array Z_broad using print() function to see its values

print(<<your code comes here>>)

Here you will observe that X_broad and Y_broad are added by the second rule of Broadcasting.

See Answer

No hints are availble for this assesment

Loading comments...