D3 Examples - Geo Visualization Workshop

Template
Here you will find an HTML template for the geo-viz workshop. We'll be adding javascript code to the section between the opening and closing <script></script> tags in the index.html file. There are already some variables there to help us get started with.
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<!DOCTYPE html>
<html>
<head>
    <meta charset='utf-8' />
    <title>iSchool GeoVisualization Workshop</title>
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src="//d3js.org/d3.v4.min.js"></script>
        <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.43.0/mapbox-gl.js'></script>
        <link href='https://unpkg.com/mapbox-gl@0.43.0/dist/mapbox-gl.css' rel='stylesheet' />
    <style>
        body { margin:0; padding:0; }
        #map { position:absolute; top:0; bottom:0; width:100%; }
    </style>
</head>
<body>
​
  <!-- this div with an id of "map" will be used to create our map -->
  <div id='map'></div>
  
<script>
​
  // javascript code goes here!!!
  
  // url to our "raw" geo data
  var dataURL = "https://raw.githubusercontent.com/clhenrick/geovisualization_workshop_ischool/master/data/nyc_crashes.geojson";
  
  // url to hexbins
  var hexBinURL = "https://gist.githubusercontent.com/clhenrick/5787a12a8bf3b02821839e4f9556d997/raw/f18f34a319380ba471078baec382970dbc64a9ff/processed.json";
​
  // access token to use with MapboxGL
  var accessToken = 'pk.eyJ1IjoiZW5qYWxvdCIsImEiOiIzOTJmMjBiZmI2NGQ2ZjAzODhiMzhiOGI2MTI1YTk4YSJ9.sIOXXU3TPp5dLg_L3cUxhQ';
​
 // set mapboxGL access token
 mapboxgl.accessToken = accessToken;
  
 //instantiate map opject 
 var map = new mapboxgl.Map({
   
   container:"map",
   style:"mapbox://stlyes/mapbox/dark-v9",
   center:[-74,40.7],
   zoom: 10
 }) ;
  
 //add map navigation controls
  map.addControl(new mapboxgl.NavigationControl());
 
 //do stuff on map load
  map.on("load", function(){
    
    //load our data
    d3.json(dataURL, function(error, data){
      
      if(error) throw error;
      
      console.log(data);
      
      map.addSource("crashes",{
        type:"geojson",
        data: data,
//         cluster: true,
//         clusterRadius: 10,
//         clusterMaxZoom: 12
      });
      
      //add the layer to the map
      map.addLayer({
        id: "crashes",
        type: "circle",
        source: "crashes",
        layout: {},
        paint: {
          "circle-color":{
            property: "crash_type",
            type: "categorical",
            stops: [
              ["no_injury_fatality","#fecc5c"],
              ["injury","#fd8d3c"],
              ["fatality","#f03b20"],
              ["injury_and_fatality","#bd0026"]
            ]
          },
          "circle-opacity": 0.8,
          "circle-radius":{
            base: 1.75,
            stops:[
              [12,2],
              [22,180]
            ]
          } 
        }
      });
    });//end d3.json
    
    //load hexbin data
    d3.json(hexBinURL, function(error, hexbins){
      if(error) throw error;
      console.log(hexbins);
      
      var colorRamp = ['#feebe2','#fcc5c0','#fa9fb5','#f768a1','#dd3497','#ae017e','#7a0177']
      map.addSource("hexGrid",{
        type: "geojson",
        data: hexbins
      });
      
      map.addLayer({
        id: "hexGrid",
        type:"fill",
        source:"hexGrid",
        layout:{},
        paint:{
          "fill-color":{
            property: "bin",
            stops: colorRamp.map(function(d,i){
              return [i,d];
          }),
        },
          "fill-opacity": 0.9
        }
      });
      
    });
    
  })//end map on load
 
 
 
 
 
 
 
 
 
 
 
 
 
  
</script>
</body>
</html>
​
    