var oldxName="";
function Changex(xName){
if (oldxName!=""){document.getElementById("x_"+oldxName).style.display="none";}
document.getElementById("x_"+xName).style.display="block";
oldxName=xName;
}
var oldyName="";
function Changey(yName){
if (oldyName!="") document.getElementById("y_"+oldyName).style.display="none";
document.getElementById("y_"+yName).style.display="block";
oldyName=yName;
}
var oldzName="";
function Changez(zName){
if (oldzName!="") document.getElementById("z_"+oldzName).style.display="none";
document.getElementById("z_"+zName).style.display="block";
oldzName=zName;
}
var oldwName="";
function Changew(wName){
if (oldwName!="") document.getElementById("w_"+oldwName).style.display="none";
document.getElementById("w_"+wName).style.display="block";
oldwName=wName;
}
//onLoad="Changex('xxx')"
//<a href="javascript:Changex('xxx')">
//<a href="javascript:void(0)" onClick="Changex('xxx')">
//<table  id="x_xxx" style="display:none">