md`# Sankey diagram showing a hierarchy`
chart = {
const edgeColor = 'none';
const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height]);
const {nodes, links} = sankey(graph);
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", d => color(d.name))
.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")
.style("mix-blend-mode", "multiply");
link.append("path")
.attr("d", d3.sankeyLinkHorizontal())
.attr("stroke", d => d.color)
.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")
// .style("font", "10px sans-serif")
// .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();
}
color = {
const color = d3.scaleOrdinal(d3.schemeCategory10);
return role => 'green'; //color(role.name);
}
format = {
const f = d3.format(",.0f");
return d => `${f(d)} TWh`;
}
graph = {
const nodes = POETS.role;
const n = (role) => nodes.find(n => n.name === name).id;
const l = (source, target, access) => ({source, target, value: 1, color: 'blue'});
const links = nodes.filter(role => !!role.role_id).map(role => ({
source: role.role_id, target: role.id, value: 1, color: 'blue'
}));
return { nodes, links}
}
width = 800;
height = 600;
sankey = {
const sankey = d3.sankey()
.nodeId(d => d.id)
.nodeAlign(d3.sankeyJustify)
.nodeWidth(10)
.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))
});
}
import {POETS} from "@cea2k/poets-data"
d3 = require("d3@5", "d3-sankey@0.12")
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