Developer, journalist
chart = {
const simulation = d3
.forceSimulation()
.force("charge", d3.forceManyBody())
.force("link", d3.forceLink().id(d => d.id))
.force("x", d3.forceX())
.force("y", d3.forceY())
.on("tick", ticked);
const svg = d3
.create("svg")
.attr("viewBox", [-width / 2, -height / 2, width, height]);
let link = svg
.append("g")
.attr("stroke", "#999")
.attr("stroke-opacity", 0.6)
.selectAll("line");
let node = svg
.append("g")
.attr("stroke", "#fff")
.attr("stroke-width", 1.5)
.selectAll("circle");
function ticked() {
node
.attr("cx", d => d.x)
.attr("fill", d => (d.infected ? 'red' : 'black'))
.attr("cy", d => d.y);
link
.attr("x1", d => d.source.x)
.attr("y1", d => d.source.y)
.attr("x2", d => d.target.x)
.attr("y2", d => d.target.y);
}
invalidation.then(() => simulation.stop());
return Object.assign(svg.node(), {
update({ nodes, links }) {
// Make a shallow copy to protect against mutation, while
// recycling old nodes to preserve position and velocity.
const old = new Map(node.data().map(d => [d.id, d]));
nodes = nodes.map(d => Object.assign(old.get(d.id) || {}, d));
links = links.map(d => Object.assign({}, d));
node = node
.data(nodes, d => d.id)
.join(enter =>
enter
.append("circle")
.attr("r", 5)
.call(drag(simulation))
.call(node => node.append("title").text(d => d.id))
);
link = link.data(links, d => [d.source, d.target]).join("line");
simulation.nodes(nodes);
simulation.force("link").links(links);
simulation
.alpha(1)
.restart()
.tick();
ticked(); // render now!
}
});
}
import { slider } from "@jashkenas/inputs"
update = {
const nodes = infectableNodes.filter(d => contains(d, time));
const links = data.links.filter(d => contains(d, time));
links.forEach(d => {
const random = Math.random();
const source = nodes.find(n => n.id == d.source);
const target = nodes.find(n => n.id == d.target);
if (random <= spreadChance) {
if (source.infected) {
target.infected = true;
} else if (d.target.infected) {
source.infected = true;
}
}
});
chart.update({ nodes, links });
}
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/random
getRandomInt = max => Math.floor(Math.random() * Math.floor(max))
mutable infectableNodes = data.nodes.map((d, i) => ({
...d,
infected: Math.random() <= initialChance
}))
data = JSON.parse(await FileAttachment("sfhh@4.json").text(), (key, value) => key === "start" || key === "end" ? new Date(value) : value)
times = d3.scaleTime()
.domain([d3.min(data.nodes, d => d.start), d3.max(data.nodes, d => d.end)])
.ticks(1000)
.filter(time => data.nodes.some(d => contains(d, time)))
contains = ({start, end}, time) => start <= time && time < end
height = 680
drag = simulation => {
function dragstarted(d) {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if (!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
return d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended);
}
d3 = require("d3@5")
import {swatches} from "@d3/color-legend"
import {Scrubber} from "@mbostock/scrubber"
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
