Used to work on @observablehq — still think it rocks.
🏍 🌎 👶
Published
Edited
Dec 18, 2019
1 star
chart = {
const svg = d3.create("svg").attr("viewBox", [0, 0, width, height]);
svg.append("g").call(xAxis);
svg.append("g").call(yAxis);
const path = svg
.append("g")
.attr("fill", "none")
.attr("stroke", "steelblue")
.attr("stroke-width", 2.5)
.attr("stroke-linejoin", "round")
.attr("stroke-linecap", "round")
.selectAll("path")
.data(data.series)
.join("path")
.style("mix-blend-mode", "multiply")
.attr("d", d => line(d.values));
svg.call(hover, path);
return svg.node();
}
raw = d3.csvParse(
await FileAttachment(
"Annual Returns on Stock, T.Bonds and T.Bills_ 1928 - Current - Sheet1.csv"
).text()
)
function parseMoney(d) {
return +d.substr(1).replace(/,/g, '');
}
formatMoney = {
const fmt = d3.format(",");
return d => "$" + fmt(Math.round(d));
}
function pluckSeries(from, name) {
return { name, values: raw.map(d => parseMoney(d[from])) };
}
data = ({
y: "Compounded value of $100, invested in 1928",
series: [
pluckSeries("Stocks", "Stocks"),
pluckSeries("T.Bills", "Treasury Bills (3 month)"),
pluckSeries("T.Bonds", "Treasury Bonds (10 year)")
],
dates: raw.map(d => new Date(d.Year + "-12-31"))
})
function hover(svg, path) {
svg.style("position", "relative");
if ("ontouchstart" in document)
svg
.style("-webkit-tap-highlight-color", "transparent")
.on("touchmove", moved)
.on("touchstart", entered)
.on("touchend", left);
else
svg
.on("mousemove", moved)
.on("mouseenter", entered)
.on("mouseleave", left);
const dot = svg.append("g").attr("display", "none");
dot.append("circle").attr("r", 2.5);
dot
.append("text")
.style("font", "bold 12px sans-serif")
.style("text-shadow", "0 0 3px white")
.attr("fill", "#000")
.attr("text-anchor", "middle")
.attr("y", -8);
function moved() {
d3.event.preventDefault();
const ym = y.invert(d3.event.layerY);
const xm = x.invert(d3.event.layerX);
const i1 = d3.bisectLeft(data.dates, xm, 1);
const i0 = i1 - 1;
const i = xm - data.dates[i0] > data.dates[i1] - xm ? i1 : i0;
const s = data.series.reduce((a, b) =>
Math.abs(a.values[i] - ym) < Math.abs(b.values[i] - ym) ? a : b
);
path
.attr("stroke", d => (d === s ? null : "#ddd"))
.filter(d => d === s)
.raise();
dot.attr("transform", `translate(${x(data.dates[i])},${y(s.values[i])})`);
dot.select("text").text(`${s.name}: ${formatMoney(s.values[i])}`);
}
function entered() {
path.style("mix-blend-mode", null).attr("stroke", "#ddd");
dot.attr("display", null);
}
function left() {
path.style("mix-blend-mode", "multiply").attr("stroke", null);
dot.attr("display", "none");
}
}
height = 600
margin = ({ top: 20, right: 80, bottom: 30, left: 50 })
x = d3.scaleUtc()
.domain(d3.extent(data.dates))
.range([margin.left, width - margin.right])
y = (scale === "linear"
? d3
.scaleLinear()
.domain([0, d3.max(data.series, d => d3.max(d.values))])
.nice()
: d3
.scaleLog()
.base(2)
.domain([50, d3.max(data.series, d => d3.max(d.values))])
).range([height - margin.bottom, margin.top])
xAxis = g => g
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(d3.axisBottom(x).ticks(width / 80).tickSizeOuter(0))
yAxis = g =>
g
.attr("transform", `translate(${margin.left},0)`)
.call(
d3
.axisLeft(y)
.tickValues(
scale === "log" ? [50, 100, 1000, 10000, 100000, 400000] : undefined
)
.tickFormat(formatMoney)
)
.call(g => g.select(".domain").remove())
.call(g =>
g
.select(".tick:last-of-type text")
.clone()
.attr("x", 3)
.attr("text-anchor", "start")
.attr("font-weight", "bold")
.style("font-size", "12px")
.text(data.y)
)
line = d3.line()
.defined(d => !isNaN(d))
.x((d, i) => x(data.dates[i]))
.y(d => y(d))
d3 = require("d3@5")
import { radio } from "@jashkenas/inputs"
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.
