chart = {
var new_england = topojson.feature(us, us.objects.counties);
var land = topojson.feature(us, {
type: "GeometryCollection",
geometries: us.objects.counties.geometries.filter(function(d) {
//var did = d.id.slice(0, 2);
var states = ["09", "25", "23", "33", "44", "50"]
return states.includes(d.id.slice(0, 2));
})
});
var projection = d3.geoIdentity().fitExtent([[20, 20], [940, 580]], new_england);
var path = d3.geoPath(projection);
const svg = d3.create("svg")
.attr("viewBox", "0 0 960 600")
.style("width", "960")
.style("height", "600");
svg.append("g")
.attr("transform", "translate(600,40)")
.call(legend);
svg.append("g")
.selectAll("path")
.data(new_england.features)
.join("path")
.attr("fill", d => color(data.get(d.id)))
.attr("d", path)
.append("title")
.text(d => `${d.properties.name}, ${states.get(d.id.slice(0, 2)).name}
${format(data.get(d.id))}`);
svg.append("path")
.datum(topojson.mesh(us, us.objects.states, (a, b) => a !== b))
.attr("fill", "none")
.attr("stroke", "white")
.attr("stroke-linejoin", "round")
.attr("d", path);
return svg.node();
}
legend = g => {
const x = d3.scaleLinear()
.domain(d3.extent(color.domain()))
.rangeRound([0, 260]);
g.selectAll("rect")
.data(color.range().map(d => color.invertExtent(d)))
.join("rect")
.attr("height", 8)
.attr("x", d => x(d[0]))
.attr("width", d => x(d[1]) - x(d[0]))
.attr("fill", d => color(d[0]));
g.append("text")
.attr("x", x.range()[0])
.attr("y", -6)
.attr("fill", "currentColor")
.attr("text-anchor", "start")
.attr("font-weight", "bold")
.text(data.title);
g.call(d3.axisBottom(x)
.tickSize(13)
.tickFormat(d => d)
.tickValues(color.range().slice(1).map(d => color.invertExtent(d)[0])))
.select(".domain")
.remove();
}
data = Object.assign(new Map(await d3.csv("https://gist.githubusercontent.com/mbostock/682b782da9e1448e6eaac00bb3d3cd9d/raw/0e0a145ded8b1672701dc8b2a702e51c648312d4/unemployment.csv", ({id, rate}) => [id, +rate])), {title: "Unemployment rate (%)"})
color = d3.scaleQuantize([1, 10], d3.schemeBlues[9])
format = d => `${d}%`
states = new Map(us.objects.states.geometries.map(d => [d.id, d.properties]))
us = d3.json("https://cdn.jsdelivr.net/npm/us-atlas@2/us/10m.json").then(function(result) {
var states = ["09", "25", "23", "33", "44", "50"]
result.objects.states.geometries = result.objects.states.geometries.filter(function(d) {
return states.includes(d.id.slice(0, 2));
});
result.objects.counties.geometries = result.objects.counties.geometries.filter(function(d) {
return states.includes(d.id.slice(0, 2));
});
return result;
});
topojson = require("topojson-client@3")
d3 = require("d3@5", "d3-geo-projection")
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