How to convert an address to longitude and latitude then display a map on the page

Question

Im trying to use google maps api to convert my address to longitude and latitude and THEN display the map on the page.

Just a note im using PHP/Laravel to retrieve the address from the DB. So although its a hard coded value of new york that will be dynamic after i get this working.

Html

<div id="map" style="height:250px"></div>

Javascript

<script>

    var geocoder = new google.maps.Geocoder();
    var address = "new york";

    geocoder.geocode( { 'address': address}, function(results, status) {

        if (status == google.maps.GeocoderStatus.OK) {
            var latitude = results[0].geometry.location.lat();
            var longitude = results[0].geometry.location.lng();
            alert(latitude);
        }
    });

    function initMap() {
        var myLatLng = {lat: latitude, lng: longitude};

        var map = new google.maps.Map(document.getElementById('map'), {
            zoom: 4,
            center: myLatLng
        });

        var marker = new google.maps.Marker({
            position: myLatLng,
            map: map,
            title: 'Hello World!'
        });
    }




</script>

<script async defer
        src="https://maps.googleapis.com/maps/api/js?key=keyremoved&callback=initMap">
</script>

At the moment i'm getting the error of "Uncaught ReferenceError: google is not defined"

Answer 1

Change the order of scripts

<script async defer
        src="https://maps.googleapis.com/maps/api/js?key=keyremoved&callback=initMap">
</script>
<script>
   var geocoder = new google.maps.Geocoder();
    var address = "new york";
   // rest of the code
</script>

Answer 2

As mentioned above the code needed to be put inside of my callback function.

<script>    
        function initMap(address) {

            var geocoder = new google.maps.Geocoder();

            geocoder.geocode( { 'address': address}, function(results, status) {

                if (status == google.maps.GeocoderStatus.OK) {
                    var latitude = results[0].geometry.location.lat();
                    var longitude = results[0].geometry.location.lng();
                }

                console.log(latitude);
                console.log(longitude);

                var myLatLng = {lat: latitude, lng: longitude};

                var map = new google.maps.Map(document.getElementById('map'), {
                    zoom: 4,
                    center: myLatLng
                });

                var marker = new google.maps.Marker({
                    position: myLatLng,
                    map: map,
                    title: 'Hello World!'
                });

            });


        }




    </script>

    <script async defer
            src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCY2buDtbYIot8Llm_FkQXHW36f0Cme6TI&callback=initMap">
    </script>