9386992 by larskotthoff

Click on any arc to zoom in. Click on the center circle to zoom out.

A sunburst is similar to a treemap, except it uses a radial layout. The root node of the tree is at the center, with leaves on the circumference. The area (or angle, depending on implementation) of each arc corresponds to its value. Sunburst design by John Stasko. Data courtesy Jeff Heer.

index.html

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

path {
  stroke: #fff;
  fill-rule: evenodd;
}

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

var width = 960,
    height = 700,
    radius = Math.min(width, height) / 2;

var x = d3.scale.linear()
    .range([0, 2 * Math.PI]);

var y = d3.scale.sqrt()
    .range([0, radius]);

var color = d3.scale.category20c();

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height)
  .append("g")
    .attr("transform", "translate(" + width / 2 + "," + (height / 2 + 10) + ")");

var partition = d3.layout.partition()
    .value(function(d) { return d.size; });

var arc = d3.svg.arc()
    .startAngle(function(d) { return Math.max(0, Math.min(2 * Math.PI, x(d.x))); })
    .endAngle(function(d) { return Math.max(0, Math.min(2 * Math.PI, x(d.x + d.dx))); })
    .innerRadius(function(d) { return Math.max(0, y(d.y)); })
    .outerRadius(function(d) { return Math.max(0, y(d.y + d.dy)); });

svg.append("circle").attr("r", radius).style("fill", "pink");

d3.json("/d/4063550/flare.json", function(error, root) {
  var path = svg.selectAll("path")
      .data(partition.nodes(root))
    .enter().append("path")
      .attr("d", arc)
      .style("fill", function(d) { return color((d.children ? d : d.parent).name); })
      .on("click", click);

  function click(d) {
    path.transition()
      .duration(750)
      .attrTween("d", arcTween(d));
  }
});

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

// Interpolate the scales!
function arcTween(d) {
  var xd = d3.interpolate(x.domain(), [d.x, d.x + d.dx]),
      yd = d3.interpolate(y.domain(), [d.y, 1]),
      yr = d3.interpolate(y.range(), [d.y ? 20 : 0, radius]);
  return function(d, i) {
    return i
        ? function(t) { return arc(d); }
        : function(t) { x.domain(xd(t)); y.domain(yd(t)).range(yr(t)); return arc(d); };
  };
}

</script>