A Javascript Function to position one element around a different element

PosisitonIt.js

function positionIt($element, $anchorElement, verticalPercent, horizontalPercent)
{
	if(!($localElement instanceof jQuery))
	{
		throw '$element must be a jQuery object';
		return;
	}

	if(!($anchorElement instanceof jQuery))
	{
		throw '$anchorElement must be a jQuery object';
		return;
	}

	if(verticalPercent > 100 || verticalPercent < 0)
	{
		throw 'verticalPercent must be between 0 and 100';
	}

	if(horizontalPercent > 100 || horizontalPercent < 0)
	{
		throw 'horizontalPercent must be between 0 and 100';
	}

	//Get the starting offset for the element;
	var baseOffset = $anchorElement.offset();

	var width = $anchorElement.outerWidth();
	var height = $anchorElement.outerHeight();
	var top = baseOffset.top + (height * parseFloat(verticalPercent) / 100.0);
	var left = baseOffset.left + (width * parseFloat(horizontalPercent) / 100.0);

	$element.css({'top': top, 'left': left, 'position': 'absolute'});
}

Need to out inside vs outside positions.