function go(loc){
    var ifrm = document.getElementById('graph');
	ifrm.src = "index_"+loc+".html";
   
	var doc=ifrm.contentWindow.document;
	var body_ = doc.body, html_ = doc.documentElement;
	var height = Math.max( body_.scrollHeight, body_.offsetHeight, html_.clientHeight, html_.scrollHeight, html_.offsetHeight );
	ifrm.style.height=height;
}