code: function(pos, prop) {
       prop = $.splat(prop);
       this.viz.graph.eachNode(function(elem) {
           $.each(prop, function(p) { elem.getPos(p).$add(pos); });
       });
    }
docs: /*
  Applies a translation to the tree.
  
  Parameters:
  
  pos - A <Complex> number specifying translation vector.
  prop - A <Graph.Node> position property ('pos', 'start' or 'end').
  
  Example:
  
  (start code js)
  st.geom.translate(new Complex(300, 100), 'end');
  (end code)