basic pie by jwilber

index.html

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v5.min.js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; }
  </style>
</head>

<body>
<svg width="300" height="300"> </svg>
<script>
  var data = {
    labels: ['a', 'b', 'c', 'd'],
    values: [1, 2, 3, 4]
  };
  
//     var data = [2, 4, 8, 10];

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

    var color = d3.scaleOrdinal(['#4daf4a','#377eb8','#ff7f00','#984ea3','#e41a1c']);

    // Generate the pie
    var pie = d3.pie();

    // Generate the arcs
    var arc = d3.arc()
                .innerRadius(0)
                .outerRadius(radius);

    //Generate groups
    var arcs = g.selectAll("arc")
                .data(pie(data.values))
                .enter()
                .append("g")
                .attr("class", "arc")

    //Draw arc paths
    arcs.append("path")
        .attr("fill", function(d, i) {
            return color(i);
        })
        .attr("d", arc);
</script>
</body>

</body>