How to Access and Print Matrix Element at Specific Position in PHP ?

Accessing and printing elements at specific positions within a matrix is a fundamental operation in PHP when dealing with two-dimensional arrays. A matrix in PHP can be represented as an array of arrays, where each sub-array represents a row in the matrix. This article explores various approaches to access and print a matrix element at a specific position, complete with code examples.

Approach 1: Direct Access

The basic method to access a matrix element is by directly referencing its row and column indexes. This method is best used when you know the exact position of the element you want to access.

PHP

<?php

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

// Accessing the element at
// row 2, column 3
$rowIndex = 1;
$colIndex = 2;

echo "Element at row 2, column 3: "
    . $matrix[$rowIndex][$colIndex];

?>

Output

Element at row 2, column 3: 6

Approach 2: Using Loops

For a more dynamic approach, especially when the position may vary based on some condition or input, loops can be used to iterate through the matrix and access elements.

PHP

<?php

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

// Assuming we want to access an
// element at a dynamic position
$rowIndex = 2; // Target row
$colIndex = 1; // Target column

foreach ($matrix as $row => $cols) {
    if ($row == $rowIndex) {
        foreach ($cols as $col => $value) {
            if ($col == $colIndex) {
                echo "Element at row $rowIndex, column $colIndex: $value\n";
                break;
            }
        }
        break;
    }
}

?>

Output

Element at row 2, column 1: 8

Approach 3: Using Array Functions

PHP’s array functions can also facilitate the access of specific elements. Functions like array_column can be particularly useful for extracting a column, after which accessing a specific row is straightforward.

PHP

<?php

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

// Accessing the element at
// row 3, column 2
$colIndex = 1;
$rowIndex = 2;
$column = array_column($matrix, $colIndex);

echo "Element at row 3, column 2: " . $column[$rowIndex];

?>

Output

Element at row 3, column 2: 8