var isOpera = navigator.userAgent.indexOf("Opera") > -1;
var isIE = navigator.userAgent.indexOf("MSIE") > 1 && !isOpera;
var isMoz = navigator.userAgent.indexOf("Mozilla/5.") == 0 && !isOpera;

function px_to_num(myx)
{
    if(myx.length == undefined)
    {
        return myx;
    }
    
    myx = new String(myx);
    myx = parseInt(myx.substr(0, myx.length-2));
    
    return myx;
}