Function partition

d3-3.2.8/d3.js:5827–5831

(d, i)

      return 1 + d;
    }
    function partition(d, i) {
      var nodes = hierarchy.call(this, d, i);
      position(nodes[0], 0, size[0], size[1] / depth(nodes[0]));
      return nodes;
    }
    partition.size = function(x) {
      if (!arguments.length) return size;
      size = x;