php ช่วยด้วยครับอยากทราบวิธีเปลี่ยนหมุด google map ครับ

<script type="text/javascript">
var locations = [


['ร้านยามหาลัย', 16.23950, 103.25698, 1]


];
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 13,
center: new google.maps.LatLng(16.23950, 103.25698),
mapTypeId: google.maps.MapTypeId.ROADMAP
});
var infowindow = new google.maps.InfoWindow();
var marker, i; for (i = 0; i < locations.length; i++) {
marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[i][1], locations[i][2]),
map: map
});

google.maps.event.addListener(marker, 'click', (function(marker, i) {
return function() {
infowindow.setContent(locations[i][0]);
infowindow.open(map, marker);
}
})
(marker, i));
}
</script>