PHP rotate matrix counter-clockwise

phparraysmatrix


PHP Snippet 1:

$b = call_user_func_array(
    'array_map',
    array(-1 => null) + array_map('array_reverse', $a)
);

PHP Snippet 2:

$a = [[1,2,3,4],[1,2,3,4],[3,4,5,6],[3,4,5,6]];

var_export(array_reverse(array_map(null, ...$a)));

PHP Snippet 3:

$result = [];
foreach ($array as $row) {
    foreach ($row as $i => $v) {
        $result[$i][] = $v;
    }
}
var_export(array_reverse($result));

PHP Snippet 4:

$result = [];
foreach ($array as $row) {
    foreach (array_reverse($row) as $i => $v) {
        $result[$i][] = $v;
    }
}
var_export($result);

PHP Snippet 5:

$a = array(array(1,2,3,4),array(5,6,7,8),array(9,0,1,2),array(3,4,5,6));
$b = $a; //result

$clockwise = false;  // toggle for clockwise / counter-clockwise

$rows = count($a);
$columns = ($rows > 0) ? count($a[0]) : 0;

for ($y = 0; $y < $rows; $y++) {
  for ($x = 0; $x < $columns; $x++) {
    $newX = $clockwise ? $y                  : ($rows - 1) - $y;
    $newY = $clockwise ? ($columns - 1) - $x : $x;
    $b[$newX][$newY] = $a[$x][$y];
  }
}

PHP Snippet 6:

            $m = array();
            $m[0] = array('a', 'b', 'c');
            $m[1] = array('d', 'e', 'f');
            $m[2] = array('g', 'h', 'i');
            $newMatrix = array();

            function rotateMatrix($m, $i = 0, &$newMatrix)
            {
                foreach ($m as $chunk) {
                    $newChunk[] = $chunk[$i];
                }
                $newMatrix[] = array_reverse($newChunk);
                $i++;

                if ($i < count($m)) {
                    rotateMatrix($m, $i, $newMatrix);
                }
            }

            rotateMatrix($m, 0, $newMatrix);
            echo '<pre>';
            var_dump($newMatrix);
            echo '<pre>';

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