JSFiddle - React, Tailwind, and code Playground

by Simon Raper

CSS

.link {
    stroke: #000;
    stroke-width: 1.5px;
}
.node {
    fill: #1f77b4;
    stroke: #fff;
    stroke-width: 1.5px;
}

JavaScript

var width = 960,
    height = 500;

var color = d3.scale.category10();

var linkData = [2, a={source: a, target: b}, {source: a, target: c}, {source: b, target: c}];

alert(linkData[1]);

var nodes = [],
    links = [];

var force = d3.layout.force()
    .nodes(nodes)
    .links(links)
    .charge(-400)
    .linkDistance(120)
    .size([width, height])
    .on("tick", tick);

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height);

var node = svg.selectAll(".node"),
    link = svg.selectAll(".link");

var a = {id: "a"}, b = {id: "b"}, c = {id: "c"}, d={id: "d"};
  nodes.push(a, b, c, d);
for (var i = 0; i < 4; i++){
  links.push({source: nodes[i], target: b}, {source: nodes[i], target: d}, {source: nodes[i], target: c});
}
start();

function start() {
  link = link.data(force.links(), function(d) { return d.source.id + "-" + d.target.id; });
  link.enter().insert("line", ".node").attr("class", "link");
  link.exit().remove();

  node = node.data(force.nodes(), function(d) { return d.id;});
  node.enter().append("circle").attr("class", function(d) { return "node " + d.id; }).attr("r", 8);
  node.exit().remove();

  force.start();
}

function tick() {
  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; });
}