Published
Edited
Sep 23, 2022
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chart = {
const svg = d3.create("svg")
.attr("viewBox", [-600,-600,1200,1200]);

const chords = chord(matrix);

const group = svg.append("g")
.attr("font-size", 14)
.attr("font-family", "sans-serif")
.selectAll("g")
.data(chords.groups)
.join("g");

group.append("path")
.attr("fill", d => color(d.value))
.attr("d", arc);

group.append("text")
.each(d => (d.angle = (d.startAngle + d.endAngle) / 2))
.attr("dy", "0.35em")
.attr("transform", d => `
rotate(${(d.angle * 180 / Math.PI - 90)})
translate(${outerRadius + 5})
${d.angle > Math.PI ? "rotate(180)" : ""}
`)
.attr("text-anchor", d => d.angle > Math.PI ? "end" : null)
.text(d => names[d.index]);

group.append("title")
.text(d => `${names[d.index]}
${d3.sum(chords, c => (c.source.index === d.index) * c.source.value)} outgoing →
${d3.sum(chords, c => (c.target.index === d.index) * c.source.value)} incoming ←`);

svg.append("g")
.attr("fill-opacity", 0.75)
.selectAll("path")
.data(chords)
.join("path")
.style("mix-blend-mode", "multiply")
.attr("fill", d => color(d.target.value))
.attr("d", ribbon)
.append("title")
.text(d => `${names[d.source.index]} → ${names[d.target.index]} ${d.source.value}`);

return svg.node();
}
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data = d3.csvParse(await FileAttachment("saivacollaboratorguide-3 (1)@2.csv").text(), d3.autoType)
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names = Array.from(new Set(data.flatMap(d => [d.source, d.target])))
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matrix = {
const index = new Map(names.map((name, i) => [name, i]));
const matrix = Array.from(index, () => new Array(names.length).fill(0));
for (const {source, target, value} of data) matrix[index.get(source)][index.get(target)] += value;
return matrix;
}
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chord = d3.chordDirected()
.padAngle(12 / innerRadius)
.sortSubgroups(d3.descending)
.sortChords(d3.descending)
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arc = d3.arc()
.innerRadius(innerRadius)
.outerRadius(outerRadius)
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ribbon = d3.ribbonArrow()
.radius(innerRadius - 0.5)
.padAngle(1 / innerRadius)
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customcolor = Array.from(new Set(data.map(d => [d.color,d.value])))
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color = d3.scaleOrdinal(names, d3.schemeCategory10)
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formatValue = x => `${x.toFixed(0)}B`
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outerRadius = innerRadius + 6
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innerRadius = Math.min(width, height) * 0.5 - 20
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width = 840
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height = width
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d3 = require("d3@6")
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