Data Visualization Consultant, and an enthusiastic generalist in building software systems
chart = {
const svg = d3.create("svg").attr("viewBox", [0, 0, width, height]);
const { nodes, links } = sankey(data);
svg
.append("g")
.attr("stroke", "#000")
.selectAll("rect")
.data(nodes)
.join("rect")
.attr("x", (d) => d.x0)
.attr("y", (d) => d.y0)
.attr("height", (d) => d.y1 - d.y0)
.attr("width", (d) => d.x1 - d.x0)
.attr("fill", color)
.on("click", highlight_node_links)
.append("title")
.text((d) => `${d.name}\n${format(d.value)}`);
const link = svg
.append("g")
.attr("fill", "none")
.attr("stroke-opacity", 0.5)
.selectAll("g")
.data(links)
.join("g")
.attr("id", function (d, i) {
d.id = i;
return "link-" + i;
})
.style("mix-blend-mode", "multiply");
if (edgeColor === "path") {
const gradient = link
.append("linearGradient")
.attr("id", (d) => (d.uid = DOM.uid("link")).id)
.attr("gradientUnits", "userSpaceOnUse")
.attr("x1", (d) => d.source.x1)
.attr("x2", (d) => d.target.x0);
gradient
.append("stop")
.attr("offset", "0%")
.attr("stop-color", (d) => color(d.source));
gradient
.append("stop")
.attr("offset", "100%")
.attr("stop-color", (d) => color(d.target));
}
link
.append("path")
.attr("d", d3.sankeyLinkHorizontal())
.attr("stroke", (d) =>
edgeColor === "none"
? "#aaa"
: edgeColor === "path"
? d.uid
: edgeColor === "input"
? color(d.source)
: color(d.target)
)
.attr("stroke-width", (d) => Math.max(1, d.width));
link
.append("title")
.text((d) => `${d.source.name} → ${d.target.name}\n${format(d.value)}`);
svg
.append("g")
.attr("font-family", "sans-serif")
.attr("font-size", 10)
.selectAll("text")
.data(nodes)
.join("text")
.attr("x", (d) => (d.x0 < width / 2 ? d.x1 + 6 : d.x0 - 6))
.attr("y", (d) => (d.y1 + d.y0) / 2)
.attr("dy", "0.35em")
.attr("text-anchor", (d) => (d.x0 < width / 2 ? "start" : "end"))
.text((d) => d.name);
return svg.node();
}
function highlight_node_links(ev, node) {
var remainingNodes = [],
nextNodes = [];
var stroke_opacity = 0;
if (d3.select(this).attr("data-clicked") == "1") {
d3.select(this).attr("data-clicked", "0");
stroke_opacity = 0.5;
} else {
d3.select(this).attr("data-clicked", "1");
stroke_opacity = 0.9;
}
var traverse = [
{
linkType: "sourceLinks",
nodeType: "target"
},
{
linkType: "targetLinks",
nodeType: "source"
}
];
traverse.forEach(function (step) {
node[step.linkType].forEach(function (link) {
remainingNodes.push(link[step.nodeType]);
highlight_link(link.id, stroke_opacity);
});
while (remainingNodes.length) {
nextNodes = [];
remainingNodes.forEach(function (node) {
node[step.linkType].forEach(function (link) {
nextNodes.push(link[step.nodeType]);
highlight_link(link.id, stroke_opacity);
});
});
remainingNodes = nextNodes;
}
});
}
function highlight_link(id, opacity) {
d3.select("#link-" + id).style("stroke-opacity", opacity);
}
sankey = {
const sankey = d3.sankey()
.nodeId(d => d.name)
.nodeAlign(d3[`sankey${align[0].toUpperCase()}${align.slice(1)}`])
.nodeWidth(15)
.nodePadding(10)
.extent([[1, 5], [width - 1, height - 5]]);
return ({nodes, links}) => sankey({
nodes: nodes.map(d => Object.assign({}, d)),
links: links.map(d => Object.assign({}, d))
});
}
format = {
const format = d3.format(",.0f");
return data.units ? d => `${format(d)} ${data.units}` : format;
}
color = {
const color = d3.scaleOrdinal(d3.schemeCategory10);
return d => color(d.category === undefined ? d.name : d.category);
}
data = {
const links = await FileAttachment("energy.csv").csv({typed: true});
const nodes = Array.from(new Set(links.flatMap(l => [l.source, l.target])), name => ({name, category: name.replace(/ .*/, "")}));
return {nodes, links, units: "TWh"};
}
width = 954
height = 600
d3 = require("d3@6", "d3-sankey@0.12")
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