Visualization toolmaker. Founder @observablehq. Creator @d3. Former @nytgraphics. Pronounced BOSS-tock.
chart = {
const svg = d3.create("svg")
.attr("viewBox", [0, 0, 975, 610]);
svg.append("path")
.datum(topojson.feature(us, us.objects.nation))
.attr("fill", "#ddd")
.attr("d", path);
svg.append("path")
.datum(topojson.mesh(us, us.objects.states, (a, b) => a !== b))
.attr("fill", "none")
.attr("stroke", "white")
.attr("stroke-linejoin", "round")
.attr("d", path);
const legend = svg.append("g")
.attr("fill", "#777")
.attr("transform", "translate(915,608)")
.attr("text-anchor", "middle")
.style("font", "10px sans-serif")
.selectAll("g")
.data(radius.ticks(4).slice(1))
.join("g");
legend.append("circle")
.attr("fill", "none")
.attr("stroke", "#ccc")
.attr("cy", d => -radius(d))
.attr("r", radius);
legend.append("text")
.attr("y", d => -2 * radius(d))
.attr("dy", "1.3em")
.text(radius.tickFormat(4, "s"));
svg.append("g")
.attr("fill", "brown")
.attr("fill-opacity", 0.5)
.attr("stroke", "#fff")
.attr("stroke-width", 0.5)
.selectAll("circle")
.data(data
.filter(d => d.position)
.sort((a, b) => d3.descending(a.value, b.value)))
.join("circle")
.attr("transform", d => `translate(${d.position})`)
.attr("r", d => radius(d.value))
.append("title")
.text(d => `${d.title}
${format(d.value)}`);
return svg.node();
}
rawdata = d3.csv("https://raw.githubusercontent.com/nytimes/covid-19-data/master/live/us-counties.csv")
data = rawdata.map(d => ({
id: d.fips,
date: parseDate(d.date),
position: position(d),
title: d.county === "Unknown" ? d.state : `${d.county}, ${d.state}`,
value: +d[metric]
}))
function position({fips, state, county}) {
if (!fips) switch (`${county}, ${state}`) {
case "New York City, New York": return projection([-74.0060, 40.7128]);
case "Kansas City, Missouri": return projection([-94.5786, 39.0997]);
}
const feature = features.get(fips);
return feature && path.centroid(feature);
}
parseDate = d3.utcParse("%Y-%m-%d")
date = data[0].date
radius = d3.scaleSqrt([0, 200000], [0, 60])
features = new Map(topojson.feature(us, us.objects.counties).features.map(d => [d.id, d]))
path = d3.geoPath()
projection = d3.geoAlbersUsa().scale(1300).translate([487.5, 305])
format = d3.format(",.0f")
us = FileAttachment("counties-albers-10m.json").json()
topojson = require("topojson-client@3")
d3 = require("d3@5", "d3-array@2")
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.
