Google Maps Selec Location

<select id="mySelect" onchange="myFunction()">
  <option>Tampilkan maps</option>
  <option value="<?php echo $model['location_lat'] . ',' . $model['location_long']; ?>">device</option>
  <option value="<?php echo $model['device_lat'] . ',' . $model['device_long']; ?>">device2</option>
</select>




                                       <script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>

                                       <div id="map" style="width: 860px; height: 300px;"></div>

        <script type="text/javascript">
        function myFunction() {

            var x = document.getElementById("mySelect").value;
            alert(x);
              var myLatlng = new google.maps.LatLng(<?php echo $model['location_lat'];?>,<?php echo $model['location_long'];?>);
              var myOptions = {
                  zoom: 13,
                  center: myLatlng
              };
              var map = new google.maps.Map(document.getElementById("map"), myOptions);
              var marker = new google.maps.Marker({
                   position: myLatlng,
                   map: map,
                   title:"Location",
                   icon:"https://upload.wikimedia.org/wikipedia/commons/0/03/Bigcity_red.png",
                   description:"ass"
              });
          }
        </script>