var pack = d3.layout.pack()
    .size([r, r])
    .children(function(d) {
        return d.values; // accessor for children
    })
    .value(function(d) {
        return d.values; // accessor for values
    });

//Declare SVG attributes
var svg = d3.select("body").append("svg")
    .attr("width", w)
    .attr("height", w)
    .append("g")
    .attr("transform", "translate(" + (w - r) / 2 + "," + (w - r) / 2 + ")");