I had a lot of fun with this one, a data-intensive, chart-forward site with choropleths, bar charts, spider charts, and a bunch of other things. The clients needed quite a few specific use cases handled, including fine-tuned behavior on hover popups, filtered displays, and comparative rankings. The data included extremely high-precision numbers, which was its own brand of interesting.
We started with D3 at first, as it appeared to have better choropleth support and granular adjustments because of the use of SVGs, but wound up shifting to the canvas-based Chart.js library partway through, as it proved a better fit for the client's developing needs.
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