Published
Edited
Jun 9, 2020
Insert cell
Insert cell
chart = {
const root = partition(data);
let focus = root;

const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height])
.style("font", "10px sans-serif");

const cell = svg
.selectAll("g")
.data(root.descendants())
.join("g")
.attr("transform", d => `translate(${d.y0},${d.x0})`);

const rect = cell.append("rect")
.attr("width", d => d.y1 - d.y0 - 1)
.attr("height", d => rectHeight(d))
.attr("fill-opacity", 0.6)
.attr("fill", d => {
if (!d.depth) return "#ccc";
while (d.depth > 1) d = d.parent;
return color(d.data.name);
})
.style("cursor", "pointer")
.on("click", clicked);

const text = cell.append("text")
.style("user-select", "none")
.attr("pointer-events", "none")
.attr("x", 4)
.attr("y", 13)
.attr("fill-opacity", d => +labelVisible(d));

text.append("tspan")
.text(d => d.data.name);

const tspan = text.append("tspan")
.attr("fill-opacity", d => labelVisible(d) * 0.7)
.text(d => ` ${format(d.value)}`);

cell.append("title")
.text(d => `${d.ancestors().map(d => d.data.name).reverse().join("/")}\n${format(d.value)}`);

function clicked(p) {
focus = focus === p ? p = p.parent : p;

root.each(d => d.target = {
x0: (d.x0 - p.x0) / (p.x1 - p.x0) * height,
x1: (d.x1 - p.x0) / (p.x1 - p.x0) * height,
y0: d.y0 - p.y0,
y1: d.y1 - p.y0
});

const t = cell.transition().duration(750)
.attr("transform", d => `translate(${d.target.y0},${d.target.x0})`);

rect.transition(t).attr("height", d => rectHeight(d.target));
text.transition(t).attr("fill-opacity", d => +labelVisible(d.target));
tspan.transition(t).attr("fill-opacity", d => labelVisible(d.target) * 0.7);
}
function rectHeight(d) {
return d.x1 - d.x0 - Math.min(1, (d.x1 - d.x0) / 2);
}

function labelVisible(d) {
return d.y1 <= width && d.y0 >= 0 && d.x1 - d.x0 > 16;
}
return svg.node();
}
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topicsFileData = FileAttachment("topics.json").text()
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data = JSON.parse(('{"label": "Constitute", "topics": ' + topicsFileData + '}').replace(/"label"/g, '"name"').replace(/"count"/g, '"value"'))
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partition = data => {
const root = d3.hierarchy(data, d => d.topics)
.sum(d => d.value)
.sort((a, b) => b.height - a.height || b.value - a.value);
return d3.partition()
.size([height, (root.height + 1) * width / 3])
(root);
}
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color = d3.scaleOrdinal(d3.quantize(d3.interpolateRainbow, data.topics.length + 1))
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format = d3.format(",d")
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width = 975
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height = 1200
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d3 = require("d3@5")
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