php-ml/src/Math/Distance/Chebyshev.php
2018-02-10 12:08:58 +01:00

31 lines
610 B
PHP

<?php
declare(strict_types=1);
namespace Phpml\Math\Distance;
use Phpml\Exception\InvalidArgumentException;
use Phpml\Math\Distance;
class Chebyshev implements Distance
{
/**
* @throws InvalidArgumentException
*/
public function distance(array $a, array $b): float
{
if (count($a) !== count($b)) {
throw InvalidArgumentException::arraySizeNotMatch();
}
$differences = [];
$count = count($a);
for ($i = 0; $i < $count; ++$i) {
$differences[] = abs($a[$i] - $b[$i]);
}
return max($differences);
}
}