d3.js

https://d3js.org/

The JavaScript library for bespoke data visualization
Create custom dynamic visualizations with unparalleled flexibility

I've used d3 for a bunch of projects:

• nba stats explorer and the team efficiency chart
• portland reassessment map
• lichesstree
• radial NCAA tournament bracket
• NCAA tournament randomizer
• this map of the provenance of US and Canadian runners of the Boston marathon
• a graph of relative covid rates
  • (the data is all messed up now, so it no longer looks like it should, sadly)
• soccer team ratings, an experiment in displaying a sparkline-like graphic in a table
• Some solving-sol drawings, lightly interactive. Click and drag to experiment
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  • 016
  • 046
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  • 130
  • 1136
    • my personal favorite, which I blogged about because I had to learn about bezier curves to draw it

And wrote a few blog posts:

• bundle d3 with esbuild
• some tooltip options for d3
• making a US map for the web with d3
• making a US state choropleth
• making a grid choropleth with d3