Published
Edited
Aug 30, 2021
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{
const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height]);
svg.append("g")
.call(xAxis);
svg.append("g")
.call(yAxis);
svg.append("g")
.attr("fill", "none")
.attr("stroke", "steelblue")
.attr("stroke-linejoin", "round")
.selectAll("path")
.data(contours)
.join("path")
.attr("stroke-width", (d, i) => i % 5 ? 0.25 : 1)
.attr("d", d3.geoPath());
svg.append("g")
.attr("stroke", "white")
.selectAll("circle")
.data(data)
.join("circle")
.attr("cx", d => x(d.x))
.attr("cy", d => y(d.y))
.attr("r", 2);
return svg.node();
}
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x = d3.scaleLinear()
.domain(d3.extent(data, d => d.x)).nice()
.rangeRound([margin.left, width - margin.right])
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y = d3.scaleLinear()
.domain(d3.extent(data, d => d.y)).nice()
.rangeRound([height - margin.bottom, margin.top])
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xAxis = g => g.append("g")
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(d3.axisBottom(x).tickSizeOuter(0))
.call(g => g.select(".domain").remove())
.call(g => g.select(".tick:last-of-type text").clone()
.attr("y", -3)
.attr("dy", null)
.attr("font-weight", "bold")
.text(data.x))
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yAxis = g => g.append("g")
.attr("transform", `translate(${margin.left},0)`)
.call(d3.axisLeft(y).tickSizeOuter(0))
.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")
.text(data.y))
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height = 600
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margin = ({top: 20, right: 30, bottom: 30, left: 40})
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contours = d3.contourDensity()
.x(d => x(d.x))
.y(d => y(d.y))
.size([width, height])
.bandwidth(30)
.thresholds(30)
(data)
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data = Object.assign(d3.tsvParse(await FileAttachment("faithful.tsv").text(), ({waiting: x, eruptions: y}) => ({x: +x, y: +y})), {x: "Idle (min.)", y: "Erupting (min.)"})
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d3 = require("d3@6")
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