docs: function() {
      var maxValue = 0;
      this.sb.graph.eachNode(function(n) {
        var valArray = n.getData('valueArray'),
            acum = 0;
        $.each(valArray, function(v) { 
          acum += +v;
        });
        maxValue = maxValue>acum? maxValue:acum;
      });
      return maxValue;
    }