Public
Edited
Aug 22, 2023
Paused
17 forks
47 stars
Insert cell
Insert cell
Insert cell
chart = {

// Declare the chart dimensions and margins.
const width = 928;
const height = 720;
const marginTop = 10;
const marginRight = 10;
const marginBottom = 30;
const marginLeft = 40;
// Declare the scales.
const x = d3.scaleUtc()
.domain(d3.extent(data, d => d.date))
.range([marginLeft, width - marginRight]);

const y = d3.scaleLinear()
.range([height - marginBottom, marginTop]);
const color = d3.scaleOrdinal()
.domain(regionRank)
.range(d3.schemeCategory10)
.unknown("gray");

// Create the SVG container.
const svg = d3.create("svg")
.attr("width", width)
.attr("height", height)
.attr("viewBox", [0, 0, width, height])
.attr("style", "max-width: 100%; height: auto;");

// Create the areas
const area = d3.area()
.x(d => x(d.data.date))
.y0(d => y(d[0]))
.y1(d => y(d[1]));
svg.append("g")
.attr("fill-opacity", 0.8)
.selectAll("path")
.data(series)
.join("path")
.attr("fill", ({key}) => color(regionByState.get(key)))
.attr("d", area)
.append("title")
.text(({key}) => key);

// Create the lines.
const midline = d3.line()
.curve(d3.curveBasis)
.x(d => x(d.data.date))
.y(d => y((d[0] + d[1]) / 2));

svg.append("g")
.attr("fill", "none")
.attr("stroke-width", 0.75)
.selectAll("path")
.data(series)
.join("path")
.attr("stroke", ({key}) => d3.lab(color(regionByState.get(key))).darker())
.attr("d", area.lineY1());

// Append a path for text labels
svg.append("defs")
.selectAll("path")
.data(series)
.join("path")
.attr("id", d => (d.id = DOM.uid("state")).id)
.attr("d", midline);

// Append the labels.
svg.append("g")
.style("font", "10px sans-serif")
.attr("text-anchor", "middle")
.selectAll("text")
.data(series)
.join("text")
.attr("dy", "0.35em")
.append("textPath")
.attr("href", d => d.id.href)
.attr("startOffset", d => `${Math.max(0.05, Math.min(0.95, d.offset = d3.maxIndex(d, d => d[1] - d[0]) / (d.length - 1))) * 100}%`)
.text(d => d.key);

// Append the axes.
svg.append("g")
.attr("transform", `translate(0,${height - marginBottom})`)
.call(d3.axisBottom(x).ticks(width / 80).tickSizeOuter(0));

svg.append("g")
.attr("transform", `translate(${marginLeft},0)`)
.call(d3.axisLeft(y).ticks(10, "%"))
.call(g => g.select(".domain").remove());

return Object.assign(svg.node(), {scales: {color}});
}
Insert cell
data = {
const years = d3.range(1790, 2000, 10);
const states = d3.tsvParse(await FileAttachment("population.tsv").text(), (d, i) => i === 0 ? null : ({name: d[""], values: years.map(y => +d[y].replace(/,/g, "") || 0)}));
states.sort((a, b) => d3.ascending(regionRank.indexOf(regionByState.get(a.name)), regionRank.indexOf(regionByState.get(b.name))) || d3.descending(d3.sum(a.values), d3.sum(b.values)));
return Object.assign(years.map((y, i) => Object.fromEntries([["date", new Date(Date.UTC(y, 0, 1))]].concat(states.map(s => [s.name, s.values[i]])))), {columns: ["date", ...states.map(s => s.name)]});
}
Insert cell
series = d3.stack()
.keys(data.columns.slice(1))
.offset(d3.stackOffsetExpand)
(data)
Insert cell
regionRank = [
"New England",
"Middle Atlantic",
"South Atlantic",
"East South Central",
"West South Central",
"East North Central",
"West North Central",
"Mountain",
"Pacific"
]
Insert cell
regionByState = {
const regions = await d3.csv("https://raw.githubusercontent.com/cphalpert/census-regions/7bdc6aa1cb0892361e90ce9ad54983041c2ad015/us%20census%20bureau%20regions%20and%20divisions.csv");
return new Map(regions.map(d => [d.State, d.Division]));
}
Insert cell

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.
Learn more