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Last active February 8, 2016 23:46
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Polymaps + D3, Part 2
license: gpl-3.0
<!DOCTYPE html>
<meta charset="utf-8">
@import url("//");
html, body {
height: 100%;
background: #E6E6E6;
margin: 0;
font: 10px sans-serif;
svg {
display: block;
circle {
stroke: black;
fill: brown;
fill-opacity: .5;
#map {
width: 960px;
height: 500px;
<div id="map"></div>
<script src="//"></script>
<script src="//"></script>
var po = org.polymaps;
// Create the map object, add it to #map…
var map =
// Add the CloudMade image tiles as a base layer…
+ "/1a1b06b230af4efdbb989ea99e9841af" //
+ "/998/256/{Z}/{X}/{Y}.png")
.hosts(["a.", "b.", "c.", ""])));
// Add the compass control on top.
// Load the station data. When the data comes back, display it.
d3.json("stations.json", function(error, data) {
if (error) throw error;
// Insert our layer beneath the compass.
var layer ="#map svg").insert("g", ".compass");
// Add an svg:g for each station.
var marker = layer.selectAll("g")
.attr("transform", transform);
// Add a circle.
.attr("r", 4.5);
// Add a label.
.attr("x", 7)
.attr("dy", ".31em")
.text(function(d) { return d.key; });
// Whenever the map moves, update the marker positions.
map.on("move", function() {
layer.selectAll("g").attr("transform", transform);
function transform(d) {
d = map.locationPoint({lon: d.value[0], lat: d.value[1]});
return "translate(" + d.x + "," + d.y + ")";
{"KMAE":[-120.12,36.98,"MADERA MUNICIPAL AIRPORT",[26,1,2,5,6,3,2,1,2,7,29,12,3]],"KSJC":[-121.92,37.37,"SAN JOSE INTERNATIONAL AIRPORT",[28,1,1,1,6,10,5,3,2,4,14,21,7]],"KMCE":[-120.50,37.28,"MERCED MUNICIPAL AIRPORT",[29,1,1,3,7,5,2,1,3,6,12,26,5]],"KMER":[-120.57,37.37,"Merced / Castle Air Force Base",[34,1,1,1,4,5,2,1,1,4,17,22,7]],"KAPC":[-122.28,38.20,"NAPA COUNTY AIRPORT",[23,2,1,6,3,3,8,18,11,13,4,3,5]],"KSUU":[-121.95,38.27,"Fairfield / Travis Air Force Base",[13,7,4,3,3,6,4,13,33,4,1,2,7]],"KSQL":[-122.25,37.52,"San Carlos Airport",[18,3,2,2,3,4,3,2,5,17,16,12,12]],"KSNS":[-121.60,36.67,"SALINAS MUNICIPAL AIRPORT",[21,1,1,6,12,3,1,2,9,21,17,5,1]],"KMOD":[-120.95,37.62,"MODESTO CITY CO SHAM FLD",[27,1,1,2,10,5,1,1,1,3,17,24,8]],"KOAK":[-122.23,37.72,"METRO OAKLAND INTERNATIONAL AIRPORT ",[16,3,3,2,4,6,3,4,9,23,20,6,2]],"KSCK":[-121.23,37.90,"STOCKTON METROPOLITAN AIRPORT ",[21,2,2,3,6,8,2,1,4,15,19,12,4]],"KCCR":[-122.05,38.00,"CONCORD BUCHANAN FIELD",[24,3,2,1,1,5,17,12,9,9,7,6,4]],"KMRY":[-121.85,36.58,"MONTEREY PENINSULA AIRPORT",[26,1,2,9,5,3,4,9,13,14,9,4,1]],"KPAO":[-122.12,37.47,"Palo Alto Airport",[31,3,1,1,2,5,1,1,1,4,10,25,14]],"KSAC":[-121.50,38.50,"SACRAMENTO EXECUTIVE AIRPORT ",[32,1,0,1,3,11,12,16,5,2,4,9,3]],"KHWD":[-122.12,37.67,"HAYWARD AIR TERMINAL",[20,2,7,2,2,6,3,3,6,23,18,6,2]],"KSTS":[-122.82,38.50,"SANTA ROSA SONOMA COUNTY",[46,1,0,1,5,13,10,4,3,3,4,6,3]],"KSMF":[-121.60,38.70,"SACRAMENTO INTERNATIONAL AIRPORT",[19,2,1,2,4,21,18,8,3,2,5,12,4]],"KNUQ":[-122.05,37.43,"MOFFETT FIELD",[35,3,1,1,4,7,2,1,2,5,6,17,15]],"KRHV":[-121.82,37.33,"San Jose / Reid / Hillv",[35,0,0,1,4,4,2,1,1,10,28,11,1]],"KWVI":[-121.78,36.93,"WATSONVILLE MUNICIPAL AIRPORT ",[44,1,2,3,4,5,7,9,8,4,6,5,2]],"KMHR":[-121.30,38.55,"Sacramento, Sacramento Mather Airport",[21,1,1,2,8,15,12,12,7,4,5,7,3]],"KVCB":[-121.95,38.38,"VACAVILLE NUT TREE AIRPORT",[36,2,1,1,2,6,10,18,10,2,2,5,6]],"KSFO":[-122.37,37.62,"SAN FRANCISCO INTERNATIONAL AIRPORT ",[13,3,3,2,3,4,4,4,7,31,20,2,3]],"KLVK":[-121.82,37.70,"LIVERMORE MUNICIPAL AIRPORT ",[32,2,7,3,1,1,2,7,9,17,16,2,1]]}
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Neat demo, thanks!

So I created and linked to my own JSON data and found two things:

  1. The map doesn't center around my JSON data. Since it's a mess to paste into the body of my template, I linked it as a <script> from elsewhere on disk. The minified JS is kinda hard to read to see if that's the case.
  2. Is switching the lat,long a standard convention? This is opposite from what the GoogleMaps API sues - which caused some confusion at first...


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um, so for those following along at home:

var map =

can be centered by doing something like so:

var map =
    .center({lat: 30.00, lon: -80.00})

Still unsure how to parse the JSON file to use the data to create a boundary box for the initial lat/long/zoom levels...

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