Choropleth with Pie Charts

This choropleth encodes unemployment rates from 2008 with a quantize scale ranging from 0 to 15%. A threshold scale is a useful alternative for coloring arbitrary ranges.

forked from mbostock's block: Choropleth

forked from larsenmtl's block: Choropleth with Pie Charts

<!DOCTYPE html>
<meta charset="utf-8">
<style>

.counties {
  fill: none;
}

.states {
  fill: none;
  stroke: #fff;
  stroke-linejoin: round;
}

.q0-9 { fill:rgb(247,251,255); }
.q1-9 { fill:rgb(222,235,247); }
.q2-9 { fill:rgb(198,219,239); }
.q3-9 { fill:rgb(158,202,225); }
.q4-9 { fill:rgb(107,174,214); }
.q5-9 { fill:rgb(66,146,198); }
.q6-9 { fill:rgb(33,113,181); }
.q7-9 { fill:rgb(8,81,156); }
.q8-9 { fill:rgb(8,48,107); }

</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script src="//d3js.org/queue.v1.min.js"></script>
<script src="//d3js.org/topojson.v1.min.js"></script>
<script>

var width = 960,
    height = 600;

var rateById = d3.map();

var quantize = d3.scale.quantize()
    .domain([0, .15])
    .range(d3.range(9).map(function(i) { return "q" + i + "-9"; }));

var projection = d3.geo.albersUsa()
    .scale(1280)
    .translate([width / 2, height / 2]);

var path = d3.geo.path()
    .projection(projection);

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height);

queue()
    .defer(d3.json, "https://gist.githubusercontent.com/mbostock/4090846/raw/d534aba169207548a8a3d670c9c2cc719ff05c47/us.json")
    .defer(d3.tsv, "unemployment.tsv", function(d) { rateById.set(d.id, +d.rate); })
		.defer(d3.csv, "data.csv", function(d) { return {Group1: +d.Group1, Group2: +d.Group2, Group3: +d.Group3, Group4: +d.Group4, lat: +d.lat, lon: +d.lon}; })
    .await(ready);

function ready(error, us, _, data) {
  if (error) throw error;

svg.append("g")
      .attr("class", "counties")
    .selectAll("path")
      .data(topojson.feature(us, us.objects.counties).features)
    .enter().append("path")
      .attr("class", function(d) { return quantize(rateById.get(d.id)); })
      .attr("d", path);

svg.append("path")
      .datum(topojson.mesh(us, us.objects.states, function(a, b) { return a !== b; }))
      .attr("class", "states")
      .attr("d", path);
  
  var arc = d3.svg.arc().innerRadius(0).outerRadius(20),               
      pie = d3.layout.pie()
       .value(function(d){ return d });

var pies = svg.selectAll('.pie')
    .data(data)
    .enter()
    .append('g')
    .attr('class', 'pie')
    .attr("transform", function(d) {
      return "translate(" + projection([d.lon, d.lat])[0] + "," + projection([d.lon, d.lat])[1] + ")";
    });

var color = d3.scale.category10()
  
  pies.selectAll('.slice')
    .data(function(d){
    return pie([d.Group1, d.Group2, d.Group3, d.Group4]); })
    .enter()
    .append('path')
    .attr('d',  arc)
    .style('fill', function(d,i){
      return color(i);
  	});   
}

d3.select(self.frameElement).style("height", height + "px");

</script>

https://d3js.org/d3.v3.min.js

https://d3js.org/queue.v1.min.js

https://d3js.org/topojson.v1.min.js