docs: function(p) {
  
              var self = this;
  
              if (p.depth > 1) p = p.parent;
              // no children
              if (!p.children) return;
  
              //console.log("zoom in p.value = " + p.value);
              //console.log("zoom in p.name = " + p.name);
              self.updateExplanation(p.value, p.name);
  
              self.zoom(p, p);
          }