// Ratio of Obese (BMI >= 30) in U.S. Adults, CDC 2008

var data = [

  , .187, .198, , .133, .175, .151, , .1, .125, .171, , .172, .133, , .108,

  .142, .167, .201, .175, .159, .169, .177, .141, .163, .117, .182, .153, .195,

  .189, .134, .163, .133, .151, .145, .13, .139, .169, .164, .175, .135, .152,

  .169, , .132, .167, .139, .184, .159, .14, .146, .157, , .139, .183, .16, .143

];

var svg = d3.select("#chart").append("svg:svg")

    .attr("width", 960)

    .attr("height", 500);

d3.json("../data/us-states.json", function(json) {

  var path = d3.geo.path();

  // A thick black stroke for the exterior.

  svg.append("svg:g")

      .attr("class", "black")

    .selectAll("path")

      .data(json.features)

    .enter().append("svg:path")

      .attr("d", path);

  // A white overlay to hide interior black strokes.

  svg.append("svg:g")

      .attr("class", "white")

    .selectAll("path")

      .data(json.features)

    .enter().append("svg:path")

      .attr("d", path);

  // The polygons, scaled!

  svg.append("svg:g")

      .attr("class", "grey")

    .selectAll("path")

      .data(json.features)

    .enter().append("svg:path")

      .attr("d", path)

      .attr("transform", function(d) {

        var centroid = path.centroid(d),

            x = centroid[0],

            y = centroid[1];

        return "translate(" + x + "," + y + ")"

            + "scale(" + Math.sqrt(data[+d.id] * 5 || 0) + ")"

            + "translate(" + -x + "," + -y + ")";

      })

      .style("stroke-width", function(d) {

        return 1 / Math.sqrt(data[+d.id] * 5 || 1);

      });

});