function initAutocomplete() {
    var lat=document.getElementById('lat').value;
    var lng=document.getElementById('lng').value;
    console.log(lat);
    console.log(lng);


    var map = new google.maps.Map(document.getElementById('map'), {
      center: {lat:lat, lng:lng},
      zoom: 13,
      mapTypeId: 'roadmap'
    });}

me da el siguiente error:

error: InvalidValueError: setCenter: not a LatLng o LatLngLiteral: in property lat: not a number