md`scaleOrdinal can takes domain undefined and null`
color(undefined)
color(null)
band=d3.scaleBand().range([1,2,3])
band(undefined)
band(null)
point=d3.scalePoint().range([10,20,30])
point(undefined)
point(null)
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.