var RampCalculator =
{
	calculate: function(heightElement, lengthElement, slope)
	{
		heightElement = $(heightElement);
		var height = new Number(heightElement.value);
		if (isNaN(height))
			$(lengthElement).innerHTML = '';
		else
		{
			var length = Math.ceil(height * slope);
			$(lengthElement).innerHTML = length > 0 ? length : '';
		}
	}
};