Inspiration from Mike Bostock's chord diagram examples and others. Also the API reference layout for the chord layout.
forked from SkiWether's block: Chord diagram showing co-occurrences.
forked from TheShetland's block: Chord diagram showing co-occurrences.
Modified http://d3js.org/d3.v3.min.js to a secure url
https://d3js.org/d3.v3.min.js