Force Layout with Value
Modifying a Force Layout
{
const height = 300;
const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height]);
const color = d3.scaleOrdinal(d3.schemeCategory10);
var a = {id: "a"},
b = {id: "b"},
c = {id: "c"},
nodes = [a, b, c],
links = [];
var simulation = d3.forceSimulation(nodes)
.force("charge", d3.forceManyBody().strength(-1000))
.force("link", d3.forceLink(links).distance(200))
.force("x", d3.forceX())
.force("y", d3.forceY())
.alphaTarget(1)
.on("tick", ticked);
var g = svg.append("g").attr("transform", "translate(" + width / 2 + "," + height / 2 + ")"),
link = g.append("g").attr("stroke", "#000").attr("stroke-width", 1.5).selectAll(".link"),
node = g.append("g").attr("stroke", "#fff").attr("stroke-width", 1.5).selectAll(".node");
restart();
d3.timeout(function() {
links.push({source: a, target: b}); // Add a-b.
links.push({source: b, target: c}); // Add b-c.
links.push({source: c, target: a}); // Add c-a.
restart();
}, 1000);
d3.interval(function() {
nodes.pop(); // Remove c.
links.pop(); // Remove c-a.
links.pop(); // Remove b-c.
restart();
}, 2000, d3.now());
d3.interval(function() {
nodes.push(c); // Re-add c.
links.push({source: b, target: c}); // Re-add b-c.
links.push({source: c, target: a}); // Re-add c-a.
restart();
}, 2000, d3.now() + 1000);
function restart() {
// Apply the general update pattern to the nodes.
node = node.data(nodes, function(d) { return d.id;});
node.exit().remove();
node = node.enter().append("circle").attr("fill", function(d) { return color(d.id); }).attr("r", 8).merge(node);
// Apply the general update pattern to the links.
link = link.data(links, function(d) { return d.source.id + "-" + d.target.id; });
link.exit().remove();
link = link.enter().append("line").merge(link);
// Update and restart the simulation.
simulation.nodes(nodes);
simulation.force("link").links(links);
simulation.alpha(1).restart();
}
function ticked() {
node.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; })
link.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
}
return svg.node();
}
d3 = require("d3@5")
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.
