function showradius()
{
  var radiuselement;
  var sortbox;
  var zipelement;
  var filterbox;


  sortbox = document.getElementById("sort").value;
  filterbox = document.getElementById("filter").value;
  //radiuselement = document.getElementById("radius");
  zipelement = document.getElementById("sourcezip");

  if (sortbox == 'fromzip' || filterbox == 'maxradius')
  {
    zipelement.style.display='block';
  }
  else
  {
    zipelement.style.display='none';
  }

}

function rftOnchange()
{
   var rftElement = document.getElementById("rft");
   var rftValue = rftElement.options[rftElement.selectedIndex].value;
   var gradeSelector = document.getElementById("gradeSelector");

   if (rftValue == "bike" || rftValue == "run")
   {
      gradeSelector.style.display="block";
   }
   else
   {
      gradeSelector.style.display="none";
   }
}