I have downloaded the code from http://bl.ocks.org/mbostock/raw/910126/ and I believe that I have also downloaded the correct json file (based on flare.json). However, when I run the script the sunburst chart is completely black and apparently due to error "d.parent.data is undefined" in the color function:
.attr("fill", function(d) {
return color(
(d.children ? d : d.parent).data.key);
})
Other than changing the json file the code matches the example code. The only other difference is that I am running the code as a Drupal node.