title: reading JSON for google map clustering
body: <p>I struggle with JSON and jQuery so I'm hoping to get some help figuring out what I'm doing wrong.  I am attempting to plot a series of markers using the Google Map API, feeding it JSON data, and clustering the markers.  Here is my code:</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
    &lt;head&gt;
      &lt;meta http-equiv="Content-Type" content="text/html; charset=UTF-8"&gt;
      &lt;title&gt;Cluster Map&lt;/title&gt;
      &lt;script src="http://maps.google.com/maps/api/js?sensor=false" type="text/javascript"&gt;&lt;/script&gt;
      &lt;script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"&gt;&lt;/script&gt;
      &lt;script src="http://google-maps-utility-library-v3.googlecode.com/svn/trunk/markerclusterer/src/markerclusterer.js" type="text/javascript"&gt;&lt;/script&gt;
      &lt;style&gt;
        body{
          padding:0;
          margin:0;
          font: .8em Verdana, Arial, Tahoma, sans-serif;
        }
        #map{
          height:750px;
          width:100%;
        }
        #map-container {
          padding: 6px;
          border-width: 1px;
          border-style: solid;
          border-color: #ccc #ccc #999 #ccc;
          -webkit-box-shadow: rgba(64, 64, 64, 0.5) 0 2px 5px;
          -moz-box-shadow: rgba(64, 64, 64, 0.5) 0 2px 5px;
          box-shadow: rgba(64, 64, 64, 0.1) 0 2px 5px;
          width: 98%;
        }
        .map-compact{
          max-width:700px;
          max-height:500px;
          border: 2px solid #ccc;
        }
        .map-container-compact{
          max-width:705px;
        }
      &lt;/style&gt;
      &lt;script type="text/javascript"&gt;
        var map;
        var markers = [];
        var infowindow = new google.maps.InfoWindow();
  
        var locations = [
              [1176,47.7771162,-116.7955848],
              [1179,43.611205,-116.206492],
              [1180,43.6468282,-116.266549],
              [1184,42.859824,-112.443284],
              [1185,43.5956343,-114.3457667],
              [1187,42.944591,-115.311806],
              [1190,45.1752265,-113.8929893],
              [1194,43.5221362,-114.3172418],
              [1195,43.644232,-116.26701],
              [1196,47.7121524,-116.8032732],
              [1199,43.558423,-116.769645],
              [1204,43.4664344,-116.6676954],
              [1209,43.622482,-116.226826],
              [1212,47.6744292,-116.7838873],
              [1224,47.7032104,-116.7834193],
              [1225,46.4176913,-116.9870599],
              [1232,43.6872404,-114.3682851],
              [1237,43.6851259,-114.3669669],
              [1240,43.6421036,-116.2081372],
              [1243,47.7187013,-116.8942952],
              [1253,42.965614,-115.443908],
              [1261,43.625014,-116.246915],
              [1268,43.596615,-116.718836],
              [1271,47.701837,-116.834145],
              [1280,47.655409,-117.015739],
              [1283,47.712077,-116.799549],
              [1290,43.647386,-116.224156],
              [1295,44.9089252,-116.0975693],
              [1297,43.5997326,-111.1112745],
              [1298,43.578648,-116.78627],
              [1299,46.4265572,-117.0083975],
              [1302,43.632576,-116.275534],
              [1314,43.6176412,-116.2141481],
              [1322,48.2954435,-116.5473894],
              [1323,42.7127802,-114.8553122],
              [1324,42.5874904,-114.8099088],
              [1325,43.671069,-116.402881],
              [1327,42.351836,-114.301682],
              [1328,44.5049268,-114.2355923],
              [1329,44.7292708,-116.4377118],
              [1330,42.8588884,-112.447434],
              [1331,44.0751148,-116.9350504],
              [1332,43.579099,-116.558992],
              [1333,43.647544,-116.27344],
              [1334,42.5763726,-114.4602915],
              [1335,44.0644155,-116.9293831],
              [1336,44.4930619,-116.01261],
              [1337,42.5561028,-114.4682842],
              [1338,44.2466996,-116.9581766],
              [1339,42.5708601,-113.7339578],
              [1340,43.6163922,-116.2027668],
              [1342,43.5866989,-116.5393165],
              [1343,42.7727802,-114.7040982],
              [1344,42.537814,-113.794064],
              [1345,43.6675249,-116.6816121],
              [1346,43.675614,-116.912361],
              [1347,43.686977,-114.371952],
              [1348,42.7242128,-114.5199076],
              [1355,43.616294,-116.2026919],
              [1357,44.0754797,-116.9348668],
              [1358,43.58822,-116.793204],
              [1359,42.564691,-114.604884],
              [1360,43.6697562,-116.6986001],
              [1361,43.4644302,-114.2617445],
              [1364,43.620536,-116.232213],
              [1365,43.6809347,-114.3644168],
              [1366,42.864466,-112.444164],
              [1367,42.9310678,-114.4096664],
              [1368,42.406315,-113.5783814],
              [1369,43.5776876,-116.193464],
              [1370,46.4875605,-115.7989265],
              [1371,42.894036,-112.441027],
              [1373,37.8551833,-96.8499825],
              [1374,43.621254,-116.285467],
              [1375,46.7326183,-117.0246528],
              [1376,43.596208,-116.390291],
              [1377,43.593472,-116.587311],
              [1378,43.608995,-116.197508],
              [1379,43.9002355,-116.20344],
              [1381,43.9746177,-116.90268],
              [1382,43.6805409,-114.3640766],
              [1383,43.607763,-116.603533],
              [1384,43.498837,-112.001354],
              [1385,42.5898024,-114.4601416],
              [1386,42.0130058,-111.8015388],
              [1387,43.5900814,-116.2671316],
              [1388,44.7259041,-116.4394012],
              [1389,42.5631093,-114.4388847],
              [1390,43.6338961,-116.2709102],
              [1392,43.634165,-116.646771],
              [1393,43.8734348,-116.5000284],
              [1394,42.6156871,-113.6720916],
              [1397,43.9661111,-111.6844444],
              [1398,43.5983945,-116.2136108],
              [1399,43.5111207,-112.0161224],
              [1400,46.7330816,-117.0148976],
              [1401,42.548872,-114.450706],
              [1402,42.537649,-113.780903],
              [1403,43.6000219,-116.1933486],
              [1405,42.0941018,-111.876875],
              [1406,45.753452,-116.315653],
              [1407,43.6918859,-116.489992],
              [1408,46.4237243,-117.0009021],
              [1409,43.5900634,-116.2658883],
              [1410,44.7311353,-116.1028401],
              [1411,43.588323,-116.529529],
              [1412,43.669416,-116.67992],
              [1413,43.8376004,-111.7781019],
              [1414,43.2198791,-112.3421011],
              [1415,42.8254335,-114.4335266],
              [1416,44.5147255,-111.2996359],
              [1417,43.630866,-116.202995],
              [1418,43.9037116,-116.9243264],
              [1419,42.550021,-114.478571],
              [1420,43.5760239,-116.274629],
              [1421,42.7241673,-114.5288892],
              [1422,43.9132029,-113.6144736],
              [1423,43.467522,-112.003148],
              [1424,43.6918329,-116.4645991],
              [1425,43.6022386,-116.2371153],
              [1426,42.854228,-112.442169],
              [1428,42.9458958,-112.4665155],
              [1429,42.9250836,-114.9684632],
              [1430,43.566832,-116.5641797],
              [1432,43.679547,-111.906763],
              [1433,43.612178,-116.39125],
              [1434,43.691227,-116.334667],
              [1436,43.48318,-112.056229],
              [1437,43.604975,-116.397312],
              [1438,43.6217852,-116.2186593],
              [1439,43.5930729,-116.193949],
              [1442,43.6043259,-116.2434629],
              [1443,46.3897613,-116.9890981],
              [1444,43.6664249,-116.692909],
              [1446,43.5642228,-116.5728247],
              [1449,43.633387,-116.253689],
              [1450,42.2298678,-111.2634005],
              [1451,43.1877135,-112.3446804],
              [1452,48.2402072,-116.8935579],
              [1453,43.8252487,-111.7895072],
              [1454,42.7241217,-114.5242275],
              [1455,48.2760802,-116.551992],
              [1456,43.5961209,-116.193083],
              [1457,42.8649244,-112.4459673],
              [1458,43.1919721,-112.3414596],
              [1459,43.6647663,-116.6905536],
              [1461,43.6516862,-116.6712311],
              [1462,43.579161,-116.172769],
              [1463,43.6496695,-116.2797695],
              [1464,43.6830057,-114.3643388],
              [1467,42.7231549,-114.5174375],
              [1468,46.4078053,-117.021797],
              [1469,44.9105972,-116.1009361],
              [1470,43.5653015,-116.5729968],
              [1471,43.616768,-116.930722],
              [1473,42.542717,-113.7932431],
              [1474,42.6684043,-113.6011401],
              [1475,42.544867,-113.793648],
              [1476,42.537811,-113.79627],
              [1479,43.4885245,-116.4057607],
              [1480,43.611487,-116.5932059],
              [1481,42.526298,-113.792321],
              [1482,43.583243,-116.556939],
              [1484,43.6145361,-116.2013916],
              [1485,42.5780886,-114.4603468],
              [1486,43.6680225,-116.6810506],
              [1487,46.1403174,-115.9788537],
              [1488,43.1311579,-115.692717],
              [1489,46.3777343,-116.9719947],
              [1490,43.6462179,-116.95169],
              [1492,46.7335277,-117.0013502],
              [1494,43.687671,-116.35495],
              [1495,48.274166,-116.5477179],
              [1497,43.5792901,-116.5594101],
              [1498,45.9268143,-116.128407],
              [1499,42.5336322,-114.364631],
              [1501,43.5902492,-116.3128768],
              [1502,46.7376573,-117.0015188]
            ];    
  
  
        function initialize() {
          geocoder = new google.maps.Geocoder();
          var center = new google.maps.LatLng(43.474144,-112.03866);
          map = new google.maps.Map(document.getElementById('map'), {
            zoom: 7,
            center: center,
            mapTypeId: google.maps.MapTypeId.ROADMAP
          });
          markMultiple();
        }
  
        function markMultiple(){
          //$.getJSON('test.json', function(data) {
          //  $.each(data, function() {
          //    var latLng =  new google.maps.LatLng(data.lat,data.lng);
          //    var content = data.id + ':' + data.lat + ',' + data.lng;
          //    markMap(latLng, content);
          //  });
          //});
  
          for (var i = 0; i &lt; locations.length; i++) {
            var loc = locations[i];
            var latLng =  new google.maps.LatLng(loc[1],loc[2]);
            var content = loc[0] + ":" + loc[1] + "," + loc[2];
            markMap(latLng, content);
          }
  
          var markerCluster = new MarkerClusterer(map, markers);
        }
  
        function markMap(position, content){
          var marker = new google.maps.Marker({
            position: position
          });
          google.maps.event.addListener(marker, 'click', function() {
            infowindow.setContent(content);
            infowindow.open(map, marker);
          });
  
          markers.push(marker);
        }
  
        google.maps.event.addDomListener(window, 'load', initialize);
      &lt;/script&gt;
    &lt;/head&gt;
    &lt;body&gt;
      &lt;div id="map-container"&gt;
        &lt;div id="map"&gt;&lt;/div&gt;
      &lt;/div&gt;
    &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>When I use a local array, it works fine.  What I'm trying to get working is the commented code.  The json file is in the same directory as my page.  I've validated my json using jsonlint.com.  </p>
  
  <p>Here is the JSON:</p>
  
  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