NumPy: Compute the multiplication of two given matrixes

Last update on March 25 2025 12:17:50 (UTC/GMT +8 hours)

1. Matrix Multiplication

Write a NumPy program to compute the multiplication of two given matrixes.

Sample Matrix:

[[1, 0], [0, 1]]
[[1, 2], [3, 4]]

Matrix multiplication, and the detailed calculation:

Sample Solution :

Python Code :

import numpy as np

# Define two 2x2 matrices 'p' and 'q'
p = [[1, 0], [0, 1]]
q = [[1, 2], [3, 4]]

# Display the original matrices 'p' and 'q'
print("Original matrices:")
print(p)
print(q)

# Perform matrix multiplication using np.dot
result1 = np.dot(p, q)

# Display the result of the matrix multiplication
print("Result of the matrix multiplication:")
print(result1) 

Sample Output:

original matrix:
[[1, 0], [0, 1]]
[[1, 2], [3, 4]]
Result of the said matrix multiplication:
[[1 2]
 [3 4]]

Explanation:

p = [[1, 0], [0, 1]]

q =

is calculated as follows:

result1[0,0] = (p[0,0] * q[0,0]) + (p[0,1] * q[1,0]) = (1 * 1) + (0 * 3) = 1

result1[0,1] = (p[0,0] * q[0,1]) + (p[0,1] * q[1,1]) = (1 * 2) + (0 * 4) = 2

result1[1,0] = (p[1,0] * q[0,0]) + (p[[[1, 2], [3, 4]]

At first two 2x2 matrixes p and q have been declared.

result1 = np.dot(p, q) This code calculates the matrix multiplication (dot product) of p and q. The dot product 1,1] * q[1,0]) = (0 * 1) + (1 * 3) = 3

result1[1,1] = (p[1,0] * q[0,1]) + (p[1,1] * q[1,1]) = (0 * 2) + (1 * 4) = 4

Finally print() function prints the resulting 2x2 matrix.

For more Practice: Solve these Related Problems:

• Multiply two matrices using np.dot and validate the result with np.matmul.
• Implement matrix multiplication for two randomly generated matrices of different dtypes and compare the outputs.
• Verify the associative property of matrix multiplication by multiplying three matrices in different orders.
• Use broadcasting to reshape arrays appropriately and compute their product element-wise before summing along an axis.

Python-Numpy Code Editor: