PHP Program to Perform Matrix Multiplication

Posted in PHP Tutorial

Updated on Jan 11, 2024

By Mari Selvan

👁️ 375 - Views

⏳ 4 mins

💬 1 Comment

PHP Program to Perform Matrix Multiplication

Photo Credit to CodeToFun

🙋 Introduction

Matrix multiplication is a fundamental operation in linear algebra and computer science. It involves multiplying two matrices to produce a third matrix.

In this tutorial, we will explore a php program that performs matrix multiplication.

We'll break down the logic step by step and provide a sample implementation.

📄 Example

Let's dive into the php code that performs matrix multiplication.

multiplyMatrices.php

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<?php
// Function to perform matrix multiplication
function multiplyMatrices($firstMatrix, $secondMatrix)
{
  $result = array_fill(0, count($firstMatrix) , array_fill(0, count($secondMatrix[0]) , 0));

  // Perform matrix multiplication
  for ($i = 0;$i < count($firstMatrix);++$i)
  {
    for ($j = 0;$j < count($secondMatrix[0]);++$j)
    {
      for ($k = 0;$k < count($secondMatrix);++$k)
      {
        $result[$i][$j] += $firstMatrix[$i][$k] * $secondMatrix[$k][$j];
      }
    }
  }

  return $result;
}

// Function to display a matrix
function displayMatrix($matrix)
{
  foreach ($matrix as $row)
  {
    echo implode("\t", $row) . PHP_EOL;
  }
}

// Sample Input (3x3 Matrices)
$firstMatrix = [[1, 2, 3], [4, 5, 6], [7, 8, 9]];

$secondMatrix = [[9, 8, 7], [6, 5, 4], [3, 2, 1]];

// Call the function to perform matrix multiplication
$resultMatrix = multiplyMatrices($firstMatrix, $secondMatrix);

// Display the matrices
echo "First Matrix:" . PHP_EOL;
displayMatrix($firstMatrix);

echo PHP_EOL . "Second Matrix:" . PHP_EOL;
displayMatrix($secondMatrix);

echo PHP_EOL . "Result Matrix:" . PHP_EOL;
displayMatrix($resultMatrix);
?>

💻 Testing the Program

Feel free to replace the sample matrices with your own 3x3 matrices in the main function to test the program with different input.

Output

First Matrix:
1   2   3
4   5   6
7   8   9

Second Matrix:
9   8   7
6   5   4
3   2   1

Result Matrix:
30   24   18
84   69   54
138  114  90

Run the program to see the result of the matrix multiplication.

🧠 How the Program Works

The program defines a function multiplyMatrices that takes two matrices ($firstMatrix and $secondMatrix) and computes their product, storing the result in the $result matrix.
It uses three nested loops to perform the matrix multiplication.
The displayMatrix function is used to display the contents of a matrix.
Sample input matrices ($firstMatrix and $secondMatrix) are provided, and the program calls the multiplication function.
The program then displays the original matrices and the result matrix.

🧐 Understanding the Concept of Matrix Multiplication

Matrix multiplication is defined as follows: given two matrices A (of dimensions m x n) and B (of dimensions n x p), the product matrix C (of dimensions m x p) is obtained by multiplying each element of a row in matrix A by the corresponding element of a column in matrix B and summing up the results.

🎉 Conclusion

Matrix multiplication is a powerful operation used in various fields, including graphics, physics simulations, and machine learning.

Understanding the logic behind matrix multiplication and implementing it in php provides a foundational understanding of linear algebra in computer science.

Feel free to experiment with different matrix sizes and values to further explore the capabilities of this program. Happy coding!