PHP-функция: absСписок php-функций

javascript:

function abs( mixed_number )  {	// Модуль числа
	// 
	// +   original by: _argos
	// +   improved by: Karol Kowalski

	return ( ( isNaN ( mixed_number ) ) ? 0 : Math.abs ( mixed_number ) );
}

//Примеры:

alert ( "\nabs(4.2) - " + abs(4.2) + 
        "\nabs(-4.2) - " + abs(-4.2) + 
        "\nabs(-5) - " + abs(-5) + 
        "\nabs('_argos') - " + abs('_argos') );