var d = document;
function $(id){return d.getElementById(id);}

// Visual
function hide(id){$(id).style.visibility = "hidden";}
function unhide(id){$(id).style.visibility = "visible";}

function numberfilter(e){ var kc;if (window.event) kc = window.event.keyCode;else kc = e.which;
return (kc>=48 && kc<=57) || !!{8:1,46:1,37:1,39:1,116:1,9:1,13:1,16:1,18:1}[kc];}