, Arpad Ray * @link http://php.net/function.asinh * @author Arpad Ray * @version $Revision: 1.2 $ * @since PHP 5 * @require PHP 3.0.0 */ function php_compat_asinh($n) { return ln($n + sqrt(1 + pow($n, 2))); } if (!function_exists('asinh')) { function asinh($n) { return php_compat_asinh($n); } }