function $() {
    var elems = [];
    for (var i=0; i<arguments.length; i++) {
        var elem = arguments[i];
        if (typeof elem == 'string') elem = document.getElementById(elem);
        if (arguments.length == 1) return elem;
        elems.push(elem);
    }
    return elems;
}
var comparisonSwap = {
	init : function()
		{
		var c = comparisonSwap;
		var oStand = $('comparison-switcher-stand');
		var oExtnd = $('comparison-switcher-extnd');
		var oPerf = $('comparison-switcher-perf');
		addEventToObject(oStand,'onclick',function(){c.swap('stand')});
		addEventToObject(oExtnd,'onclick',function(){c.swap('extnd')});
		addEventToObject(oPerf,'onclick',function(){c.swap('perf')});
		},
	swap : function(sType)
		{
		var c = comparisonSwap;
		var oSwitcher = $('comparison-switcher');
		var oTable = $('comparison-table');
		var oPerf = $('performance');
		var oFootnotes = $('footnotes');
		if (sType == 'stand')
			{
			oSwitcher.className = 'stand';
			oTable.className = 'stand';
			oFootnotes.className = "stand";
			oPerf.className = 'hidden';
			c.alternate(sType);
			}
		else if (sType == 'extnd')
			{
			oSwitcher.className = 'extnd';
			oTable.className = 'extnd';
			oFootnotes.className = "extnd";
			oPerf.className = 'hidden';
			c.alternate(sType);
			}
		else if (sType == 'perf')
			{
			oSwitcher.className = 'perf';
			oTable.className = 'hidden';
			oFootnotes.className = "hidden";
			oPerf.className = 'show';
			}
		},
	alternate : function(sType)
		{
		var oTable = $('comparison-table');
		var aTbody = oTable.getElementsByTagName('tbody');
		var aTr = aTbody[0].getElementsByTagName('tr');
		var sAlt = 'even';
		if (sType == 'stand')
			{
			for (i=0;i<aTr.length;i++)
				{
				var iPos = aTr[i].className.indexOf('extnd');
				if (iPos == -1)
					{
					aTr[i].className = sAlt;
					sAlt = (sAlt == 'even') ? 'odd' : 'even';	
					}
				}
			}
		else if (sType == 'extnd')
			{
			for (i=0;i<aTr.length;i++)
				{
				var iPos = aTr[i].className.indexOf('extnd');
				if (iPos == -1)
					{
					aTr[i].className = sAlt;
					}
				else
					{
					aTr[i].className = 'extnd '+sAlt;	
					}
				sAlt = (sAlt == 'even') ? 'odd' : 'even';	
				}
			}
		
		}
	};
//addEventToObject(window,'onload',comparisonSwap.init);