public static Transform[] parseListOfTransforms(XMLObject xo, int maxDim)
      throws XMLParseException {
    Transform[] transforms = null;

    boolean anyTransforms = false;
    for (int i = 0; i < xo.getChildCount(); ++i) {
      if (xo.getChild(i) instanceof Transform.ParsedTransform) {
        Transform.ParsedTransform t = (Transform.ParsedTransform) xo.getChild(i);
        if (transforms == null) {
          transforms = Transform.Util.getListOfNoTransforms(maxDim);
        }

        t.end = Math.max(t.end, maxDim);
        if (t.start < 0 || t.end < 0 || t.start > t.end) {
          throw new XMLParseException("Invalid bounds for transform in " + xo.getId());
        }
        for (int j = t.start; j < t.end; j += t.every) {
          transforms[j] = t.transform;
          anyTransforms = true;
        }
      }
    }
    if (anyTransforms) {
      StringBuilder sb =
          new StringBuilder("Using distributional transforms in " + xo.getId() + "\n");
      for (int i = 0; i < transforms.length; ++i) {
        if (transforms[i] != Transform.NONE) {
          sb.append("\t")
              .append(transforms[i].getTransformName())
              .append(" on index ")
              .append(i + 1)
              .append("\n");
        }
      }
      sb.append("Please cite:\n").append(Citable.Utils.getCitationString(Transform.LOG));
      Logger.getLogger("dr.utils.Transform").info(sb.toString());
    }
    return transforms;
  }
  public void proposeTree() throws OperatorFailedException {
    TreeModel tree = c2cLikelihood.getTreeModel();
    BranchMapModel branchMap = c2cLikelihood.getBranchMap();
    NodeRef i;
    double oldMinAge, newMinAge, newRange, oldRange, newAge, q;
    // choose a random node avoiding root, and nodes that are ineligible for this move because they
    // have nowhere to
    // go
    final int nodeCount = tree.getNodeCount();
    do {
      i = tree.getNode(MathUtils.nextInt(nodeCount));
    } while (tree.getRoot() == i || !eligibleForMove(i, tree, branchMap));
    final NodeRef iP = tree.getParent(i);

    // this one can go anywhere

    NodeRef j = tree.getNode(MathUtils.nextInt(tree.getNodeCount()));
    NodeRef k = tree.getParent(j);

    while ((k != null && tree.getNodeHeight(k) <= tree.getNodeHeight(i)) || (i == j)) {
      j = tree.getNode(MathUtils.nextInt(tree.getNodeCount()));
      k = tree.getParent(j);
    }

    if (iP == tree.getRoot() || j == tree.getRoot()) {
      throw new OperatorFailedException("Root changes not allowed!");
    }

    if (k == iP || j == iP || k == i) throw new OperatorFailedException("move failed");

    final NodeRef CiP = getOtherChild(tree, iP, i);
    NodeRef PiP = tree.getParent(iP);

    newMinAge = Math.max(tree.getNodeHeight(i), tree.getNodeHeight(j));
    newRange = tree.getNodeHeight(k) - newMinAge;
    newAge = newMinAge + (MathUtils.nextDouble() * newRange);
    oldMinAge = Math.max(tree.getNodeHeight(i), tree.getNodeHeight(CiP));
    oldRange = tree.getNodeHeight(PiP) - oldMinAge;
    q = newRange / Math.abs(oldRange);

    // need to account for the random repainting of iP

    if (branchMap.get(PiP.getNumber()) != branchMap.get(CiP.getNumber())) {
      q *= 0.5;
    }

    if (branchMap.get(k.getNumber()) != branchMap.get(j.getNumber())) {
      q *= 2;
    }

    tree.beginTreeEdit();

    if (j == tree.getRoot()) {

      // 1. remove edges <iP, CiP>
      tree.removeChild(iP, CiP);
      tree.removeChild(PiP, iP);

      // 2. add edges <k, iP>, <iP, j>, <PiP, CiP>
      tree.addChild(iP, j);
      tree.addChild(PiP, CiP);

      // iP is the new root
      tree.setRoot(iP);

    } else if (iP == tree.getRoot()) {

      // 1. remove edges <k, j>, <iP, CiP>, <PiP, iP>
      tree.removeChild(k, j);
      tree.removeChild(iP, CiP);

      // 2. add edges <k, iP>, <iP, j>, <PiP, CiP>
      tree.addChild(iP, j);
      tree.addChild(k, iP);

      // CiP is the new root
      tree.setRoot(CiP);

    } else {
      // 1. remove edges <k, j>, <iP, CiP>, <PiP, iP>
      tree.removeChild(k, j);
      tree.removeChild(iP, CiP);
      tree.removeChild(PiP, iP);

      // 2. add edges <k, iP>, <iP, j>, <PiP, CiP>
      tree.addChild(iP, j);
      tree.addChild(k, iP);
      tree.addChild(PiP, CiP);
    }

    tree.setNodeHeight(iP, newAge);

    tree.endTreeEdit();

    //
    logq = Math.log(q);

    // repaint the parent to match either its new parent or its new child (50% chance of each).

    if (MathUtils.nextInt(2) == 0) {
      branchMap.set(iP.getNumber(), branchMap.get(k.getNumber()), true);
    } else {
      branchMap.set(iP.getNumber(), branchMap.get(j.getNumber()), true);
    }

    if (DEBUG) {
      c2cLikelihood.checkPartitions();
    }
  }