circle overlays

Create circle overlays for the map. example: https:developers.google.commapsdocumentationjavascriptexamplescircle-simple

 Create an object containing LatLng, population.
var citymap = {};
citymap[\'chicago\'] = {
  center: new google.maps.LatLng(41.878113, -87.629798),
  population: 2842518
};
citymap[\'newyork\'] = {
  center: new google.maps.LatLng(40.714352, -74.005973),
  population: 8143197
};
citymap[\'losangeles\'] = {
  center: new google.maps.LatLng(34.052234, -118.243684),
  population: 3844829
}
var cityCircle;

function initialize() {
  var mapOptions = {
    zoom: 4,
    center: new google.maps.LatLng(37.09024, -95.712891),
    mapTypeId: google.maps.MapTypeId.TERRAIN
  };

  var map = new google.maps.Map(document.getElementById(\'map-canvas\'),
      mapOptions);

  for (var city in citymap) {
     Construct the circle for each value in citymap. We scale population by 20.
    var populationOptions = {
      strokeColor: \'#FF0000\',
      strokeOpacity: 0.8,
      strokeWeight: 2,
      fillColor: \'#FF0000\',
      fillOpacity: 0.35,
      map: map,
      center: citymap[city].center,
      radius: citymap[city].population  20
    };
    cityCircle = new google.maps.Circle(populationOptions);
  }
}

google.maps.event.addDomListener(window, \'load\', initialize);