<script>
function getLocation() {
  if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(storePosition);
  }
}
function storePosition(position) {
  var lat = document.getElementById("latitud");
  var lon = document.getElementById("longitud");
  if (lat != null && lon != null) {
    lat.value = position.coords.latitude;
    lon.value = position.coords.longitude;
  }
}
</script>