How can I start with all the nodes collapsed in d3js?

Question

Starting from this example http://bl.ocks.org/1062288 I would like to have a tree with all the nodes collapsed, so the initial graph should contain only one node (the root).

Answer 1

Option 1: Modify the JSON

Modify the JSON file, readme.json, to use _children instead of children.

Option 2: Edit the Javascript

Edit the javascript to switch the _children and children attributes for every node. This could be done like so

var nodes = flatten(root);
nodes.forEach(function(d) {
  d._children = d.children;
  d.children = null;
});

Here is a JSFiddle for the second option.