static function romanNumeral( $num ) {
		static $table = array(
			array( '', 'I', 'II', 'III', 'IV', 'V', 'VI', 'VII', 'VIII', 'IX', 'X' ),
			array( '', 'X', 'XX', 'XXX', 'XL', 'L', 'LX', 'LXX', 'LXXX', 'XC', 'C' ),
			array( '', 'C', 'CC', 'CCC', 'CD', 'D', 'DC', 'DCC', 'DCCC', 'CM', 'M' ),
			array( '', 'M', 'MM', 'MMM' )
		);

		$num = intval( $num );
		if ( $num > 3000 || $num <= 0 ) {
			return $num;
		}

		$s = '';
		for ( $pow10 = 1000, $i = 3; $i >= 0; $pow10 /= 10, $i-- ) {
			if ( $num >= $pow10 ) {
				$s .= $table[$i][floor( $num / $pow10 )];
			}
			$num = $num % $pow10;
		}
		return $s;
	}