index.html
<!DOCTYPE html>
<meta charset="utf-8">
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>
var data = [1, 1, 2, 3, 5, 8, 13, 21];
var width = 960,
height = 500,
radius = height / 2 - 10;
var arc = d3.svg.arc()
.innerRadius(radius - 40)
.outerRadius(radius)
.cornerRadius(20);
var pie = d3.layout.pie()
.padAngle(.02);
var color = d3.scale.category10();
var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(" + width / 2 + "," + height / 2 + ")");
svg.selectAll("path")
.data(pie(data))
.enter().append("path")
.style("fill", function(d, i) { return color(i); })
.attr("d", arc);
</script>