Comanche Dual

The comanche dual graph from the The University of Florida Sparse Matrix Collection.

7,922 nodes with 11,881 edges. Self-edges were removed from the links array. Nodes are colored by their velocity.

<!DOCTYPE html>
<meta charset="utf-8">
<style>
</style>
<canvas></canvas>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
var width = 960,
    height = 800;

var linkColor = d3.scaleSequential(d3.interpolateMagma)
  .domain([220, -1])

var canvas = d3.select("canvas")
    .attr("width", width)
    .attr("height", height);

var context = canvas.node().getContext("2d");

var simulation = d3.forceSimulation()
    .force("link", d3.forceLink().id(function(d) { return d.id; }).distance(0.3).strength(1.6))
    .force("charge", d3.forceManyBody().strength(-0.35).distanceMax(220))
    .force("center", d3.forceCenter(width / 2, height / 2))
//    .force("vertical", d3.forceY().strength(0.0001))
//    .force("horizontal", d3.forceX().strength(0.0001))
    .alphaDecay(0.002);

var graph = {};

d3.text("commanche_dual.mtx", function(error, raw) {
  if (error) throw error;

var node_set = d3.set();

var lines = raw.split("\n")
    .slice(15);

var pairs = lines
    .map(function(d) { return d.split(" "); });

pairs.forEach(function(d) {
    node_set.add(d[0]);
    node_set.add(d[1]);
  });

graph.nodes = node_set.values().map(function(d) {
      return {
        id: d
      };
    });

graph.links = pairs.map(function(d) {
      return {
        source: d[0],
        target: d[1]
      }
    })
    .filter(function(d) {
      return d.source !== d.target;
    });

simulation
      .nodes(graph.nodes)

simulation.force("link")
      .links(graph.links);

d3.range(10).forEach(simulation.tick);

simulation
      .on("tick", ticked);

canvas.call(d3.drag()
          .container(canvas.node())
          .subject(dragsubject)
          .on("start", dragstarted)
          .on("drag", dragged)
          .on("end", dragended));

function ticked() {
    context.clearRect(0, 0, width, height);

context.globalAlpha = 0.35;
    context.beginPath();
    context.strokeStyle = "#777";
    graph.links.forEach(drawLink);
    context.stroke();

context.globalAlpha = 1;
    context.fillStyle = "#000";
    graph.nodes.forEach(drawNode);
  }

function dragsubject() {
    return simulation.find(d3.event.x, d3.event.y);
  }
});

function dragstarted() {
  if (!d3.event.active) simulation.alphaTarget(0.8).restart();
  d3.event.subject.fx = d3.event.subject.x;
  d3.event.subject.fy = d3.event.subject.y;
}

function dragged() {
  d3.event.subject.fx = d3.event.x;
  d3.event.subject.fy = d3.event.y;
}

function dragended() {
  if (!d3.event.active) simulation.alphaTarget(0);
  d3.event.subject.fx = null;
  d3.event.subject.fy = null;
}

function drawLink(d) {
  context.moveTo(d.source.x, d.source.y);
  context.lineTo(d.target.x, d.target.y);
}

function drawNode(d) {
  context.fillStyle = d3.interpolateMagma(Math.sqrt(d.vx*d.vx + d.vy*d.vy)/1.5);
  context.fillRect(d.x-0.75, d.y-0.75, 1.5, 1.5);
}

</script>

https://d3js.org/d3.v4.min.js