Public
Edited
Aug 1, 2023
608 forks
Importers
324 stars
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chart = {

// Specify the chart’s dimensions.
const width = 928;
const height = width;

// Create the color scale.
const color = d3.scaleLinear()
.domain([0, 5])
.range(["hsl(152,80%,80%)", "hsl(228,30%,40%)"])
.interpolate(d3.interpolateHcl);

// Compute the layout.
const pack = data => d3.pack()
.size([width, height])
.padding(3)
(d3.hierarchy(data)
.sum(d => d.value)
.sort((a, b) => b.value - a.value));
const root = pack(data);

// Create the SVG container.
const svg = d3.create("svg")
.attr("viewBox", `-${width / 2} -${height / 2} ${width} ${height}`)
.attr("width", width)
.attr("height", height)
.attr("style", `max-width: 100%; height: auto; display: block; margin: 0 -14px; background: ${color(0)}; cursor: pointer;`);

// Append the nodes.
const node = svg.append("g")
.selectAll("circle")
.data(root.descendants().slice(1))
.join("circle")
.attr("fill", d => d.children ? color(d.depth) : "white")
.attr("pointer-events", d => !d.children ? "none" : null)
.on("mouseover", function() { d3.select(this).attr("stroke", "#000"); })
.on("mouseout", function() { d3.select(this).attr("stroke", null); })
.on("click", (event, d) => focus !== d && (zoom(event, d), event.stopPropagation()));

// Append the text labels.
const label = svg.append("g")
.style("font", "10px sans-serif")
.attr("pointer-events", "none")
.attr("text-anchor", "middle")
.selectAll("text")
.data(root.descendants())
.join("text")
.style("fill-opacity", d => d.parent === root ? 1 : 0)
.style("display", d => d.parent === root ? "inline" : "none")
.text(d => d.data.name);

// Create the zoom behavior and zoom immediately in to the initial focus node.
svg.on("click", (event) => zoom(event, root));
let focus = root;
let view;
zoomTo([focus.x, focus.y, focus.r * 2]);

function zoomTo(v) {
const k = width / v[2];

view = v;

label.attr("transform", d => `translate(${(d.x - v[0]) * k},${(d.y - v[1]) * k})`);
node.attr("transform", d => `translate(${(d.x - v[0]) * k},${(d.y - v[1]) * k})`);
node.attr("r", d => d.r * k);
}

function zoom(event, d) {
const focus0 = focus;

focus = d;

const transition = svg.transition()
.duration(event.altKey ? 7500 : 750)
.tween("zoom", d => {
const i = d3.interpolateZoom(view, [focus.x, focus.y, focus.r * 2]);
return t => zoomTo(i(t));
});

label
.filter(function(d) { return d.parent === focus || this.style.display === "inline"; })
.transition(transition)
.style("fill-opacity", d => d.parent === focus ? 1 : 0)
.on("start", function(d) { if (d.parent === focus) this.style.display = "inline"; })
.on("end", function(d) { if (d.parent !== focus) this.style.display = "none"; });
}

return svg.node();
}
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data = FileAttachment("flare-2.json").json()
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