Visualization toolmaker. Founder @observablehq. Creator @d3. Former @nytgraphics. Pronounced BOSS-tock.
map = {
const svg = d3.create("svg")
.attr("viewBox", [0, 0, 975, 610])
.attr("stroke-linejoin", "round");
svg.append("g")
.attr("fill", "#ccc")
.selectAll("path")
.data(features.features)
.join("path")
.attr("fill", d => color(distances.get(d.id)))
.attr("d", path)
.append("title")
.text(d => `${d.properties.name}, ${states.get(d.id.slice(0, 2)).name}
${d.id}
${distances.get(d.id)} hop${distances.get(d.id) === 1 ? "" : "s"}`);
svg.append("path")
.attr("fill", "none")
.attr("stroke", "black")
.attr("stroke-opacity", 0.5)
.attr("stroke-width", 0.5)
.attr("d", path(topojson.mesh(us, us.objects.counties, (a, b) => a !== b)));
svg.append("path")
.attr("fill", "none")
.attr("stroke", "black")
.attr("d", path(topojson.mesh(us, us.objects.states, (a, b) => a !== b)));
return svg.node();
}
path = d3.geoPath()
distances = {
let current = [...coastals];
let next = [];
let distance = 0;
const distances = new Map(features.features.map(({id}) => [id, Infinity]));
while (current.length) {
for (const id of current) {
if (distances.get(id) > distance) {
distances.set(id, distance);
next.push(...neighbors.get(id));
}
}
current = next;
next = [];
++distance;
}
return distances;
}
neighbors = new Map(topojson.neighbors(us.objects.counties.geometries).map((neighbors, i) => [features.features[i].id, neighbors.map(j => features.features[j].id)]))
features = topojson.feature(us, us.objects.counties)
states = new Map(us.objects.states.geometries.map(d => [d.id, d.properties]))
us = FileAttachment("counties-albers-10m.json").json()
coastals = new Set(d3.tsvParse(await FileAttachment("coastal-counties@5.tsv").text(), ({id}) => id))
color = d3.scaleSequentialSqrt([0, d3.max(Array.from(distances.values()))], t => d3.interpolateYlGnBu(1 - t))
topojson = require("topojson-client@3")
d3 = require("d3@5")
import {legend} from "@d3/color-legend"
One platform to build and deploy the best data apps
Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.
Use Observable Framework to build data apps locally. Use data loaders to build in any language or library, including Python, SQL, and R.
Seamlessly deploy to Observable. Test before you ship, use automatic deploy-on-commit, and ensure your projects are always up-to-date.