NumPy: Multiply a 5x3 matrix by a 3x2 matrix and create a real matrix product

NumPy Mathematics: Exercise-11 with Solution

Write a NumPy program to multiply a 5x3 matrix by a 3x2 matrix and create a real matrix product.

Sample Solution:

Python Code:

# Importing the NumPy library
import numpy as np

# Generating a random array of shape (5, 3)
x = np.random.random((5,3))

# Displaying the first array
print("First array:")
print(x)

# Generating another random array of shape (3, 2)
y = np.random.random((3,2))

# Displaying the second array
print("Second array:")
print(y)

# Computing the dot product of the two arrays
z = np.dot(x, y)

# Displaying the dot product of the arrays
print("Dot product of two arrays:")
print(z) 

Sample Output:

First array:                                                           
[[ 0.44349753  0.81043761  0.00771825]                                 
 [ 0.64004088  0.86774612  0.19944667]                                 
 [ 0.61520091  0.24796788  0.93798297]                                 
 [ 0.22156999  0.61318856  0.82348994]                                 
 [ 0.91324026  0.13411297  0.00622696]]                                
Second array:                                                          
[[ 0.73873542  0.06448186]                                             
 [ 0.90974982  0.06409165]                                             
 [ 0.22321268  0.39147412]]                                            
Dot product of two arrays:                                             
[[ 1.06664562  0.08356133]                                             
 [ 1.30677176  0.17496452]                                             
 [ 0.88942914  0.42275803]                                             
 [ 0.90534318  0.37596252]                                             
 [ 0.79804212  0.06992065]]

Explanation:

In the above code –

The np.random.random() function creates an array of random numbers between 0 and 1 of the specified shape. In this case, x is a 5x3 array and y is a 3x2 array.

The np.dot() function takes two arrays and returns their dot product, which is the matrix multiplication of the two arrays. In this case, since the first array x has shape (5,3) and the second array y has shape (3,2), their dot product will have shape (5,2).

z = np.dot(x, y) - The resulting matrix z is the product of x and y and is a 5x2 array. The value in row i and column j of z is the dot product of row i of x and column j of y.

Python-Numpy Code Editor:

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