Some functions to generate a random network. Returned objected is ready for plug-and-play use with D3 force-directed graph examples

RandomNetwork.js

function initializeNodes(n) {
  var arr = [];
  for (var i = 0; i < n; i++) {
    arr.push({id:i});
  }
  return arr;
}

function getRandomArbitrary(min, max) {
    return Math.random() * (max - min) + min;
}

function randomUndirectedEdges(n, nodesArray) {
  var links = [];
  var i = 0;
  while (i < n) {
    var edge = [
      Math.floor(getRandomArbitrary(0, nodesArray.length)),
      Math.floor(getRandomArbitrary(0, nodesArray.length))];
    var revEdge = [edge[1], edge[0]];
    if (links.indexOf(edge) === -1) {
      if (links.indexOf(revEdge) === -1) {
        if (edge[0] !== edge[1]) {
          var edgeObj = {"source": edge[0], "target": edge[1], "value": 1};
          links.push(edgeObj);
          i = i + 1;
        }
      }
    }
  }
  return links;
}

function RandomNetwork(NODES_NUM,EDGES_NUM) {
  var nodes = initializeNodes(NODES_NUM);
  var edges = randomUndirectedEdges(EDGES_NUM, nodes);
  return { "nodes" : nodes,
           "links": edges };
}

This is cool and especially useful for testing! One comment:

Both of these lines will always be false because edge and revedge are pointers to new objects each time you check. You really care about the values inside the arrays, not where they are in memory -> if (links.indexOf(edge) === -1) {
if (links.indexOf(revEdge) === -1) {