D3 3.x, HTML, CSS, JavaScript
jQuery 1.10.1, HTML, CSS, JavaScript
http://stackoverflow.com/questions/12826604/how-to-use-svg-gradients-to-display-varying-colors-relative-to-the-size-of-the-c
http://stackoverflow.com/questions/21780322/why-is-initial-drag-position-incorrect-when-using-a-scale
http://stackoverflow.com/questions/21740000/displaying-data-from-multidimensional-array-in-d3-js
...much to study here...
No-Library (pure JS), HTML, CSS, JavaScript
http://stackoverflow.com/questions/21683416/d3-js-data-update-remembers-old-data
by FernOfTheAndes
development area