function changeMenu(name, newval) {
    var target = document.getElementById(name);

    if (target) {
        for (var i = 0; i < target.length; i++)
            if (target[i].value == newval)
                target.selectedIndex = i;
    }
}
function switchMenu(id) {
  var sty = document.getElementById(id).style;
  if ( sty.display != 'block' ) {
    sty.display = 'block';
  }
  else {
    sty.display = 'none';
  }
}