Functions applied by series by Plot.map

[kletts]

I just discovered the awesome power of Plot.map's ability to apply any complex functional transformation across each series individually.

Plot.lineY(stocks, Plot.map({ y:  d => ewma(d, alpha) }, 
              { x: "Date", y: "Close", stroke: "Symbol" }))

There's an example implementation at: https://observablehq.com/d/558c4eae846df71f

While it's mentioned in the documentation
there aren't worked examples on that page where a function is used in this way. It's such a powerful feature it seems a shame it doesn't get more prominence. If you agree, feel free to adapt my linked example.