d3.rollup(electric,v=>d3.sum(v,d=>d.Usage),d=>d["Day of the week"])
d3.sum(electric,d=>d.Usage)
electric
SELECT TimeZone
, count(*)::int as records
, avg(electric."Usage"::int) as avg_usage
FROM electric
GROUP BY 1
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.