// pop-up window to view an event
function popupEvent(event_id) {
  var width = 340;
  var height = 450;
  var features = "directories=no,location=no,menubar=no,resizable=yes,scrollbars=yes,toolbar=no,status=no,width="+width+",height="+height;
  var url = "eventviewer.php?event_id="+event_id;
  open(url, "eventviewer", features).focus();
}