// common javascript functions
function addEvent(obj, evType, fn){
	if (obj.addEventListener) {
		obj.addEventListener(evType, fn, false);
		return true;
	}
	else if (obj.attachEvent) {
		var r = obj.attachEvent("on"+evType, fn);
		return r;
	}
	else {
		return false;
	}
}

function createXMLHttp() {
	if(typeof XMLHttpRequest != 'undefined') return new XMLHttpRequest();
	else if(window.ActiveXObject) {
		var avers = ["Microsoft.XmlHttp", "MSXML2.XmlHttp", "MSXML2.XmlHttp.3.0", "MSXML2.XmlHttp.4.0", "MSXML2.XmlHttp.5.0"];
		for(var i = avers.length -1; i >= 0; i--) {
			try {
				httpObj = new ActiveXObject(avers[i]);
				return httpObj;
			} catch(e) {}
		}
	}
	throw new Error('XMLHttp (AJAX) not supported');
}

function roundNumber(num, dec) {
	var result = Math.round(num*Math.pow(10,dec))/Math.pow(10,dec);
	return result;
}