chart = {
const svg = d3.create("svg")
.attr("viewBox", [-14, 0, width + 28, height])
.style("display", "block")
.style("margin", "0 -14px")
.style("background", mode === "dark" ? "#1b1e23" : "none")
.style("color", mode === "dark" ? "#fff" : "#1b1e23");
// Create a value format.
const format = y.tickFormat(20, "%");
svg.append("g")
.attr("fill", mode === "dark" ? "lightsteelblue" : "steelblue")
.selectAll("rect")
.data(data)
.join("rect")
.attr("x", (d, i) => x(i))
.attr("y", d => y(d.value))
.attr("height", d => y(0) - y(d.value))
.attr("width", x.bandwidth());
svg.append("g")
.call(xAxis);
svg.append("g")
.call(yAxis);
return svg.node();
}
mode = Generators.observe(notify => {
const query = matchMedia("(prefers-color-scheme: dark)");
const changed = () => notify(query.matches ? "dark" : "light");
changed();
query.addListener(changed);
return () => query.removeListener(changed);
})
data = d3.csvParse(await FileAttachment("alphabet.csv").text(), ({letter, frequency}) => ({name: letter, value: +frequency})).sort((a, b) => b.value - a.value)
x = d3.scaleBand()
.domain(d3.range(data.length))
.range([margin.left, width - margin.right])
.padding(0.1)
y = d3.scaleLinear()
.domain([0, d3.max(data, d => d.value)]).nice()
.range([height - margin.bottom, margin.top])
xAxis = g => g
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(d3.axisBottom(x).tickFormat(i => data[i].name).tickSizeOuter(0))
yAxis = g => g
.attr("transform", `translate(${margin.left},0)`)
.call(d3.axisLeft(y))
.call(g => g.select(".domain").remove())
height = 500
margin = ({top: 20, right: 0, bottom: 30, left: 40})
d3 = require("d3@6")
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.
