code: function modalOpen (options) {
      if (isString(options)) options = optionsFromTarget(options);
      var modal = select('#d3-view-modal');
      if (!modal.size())
          select('body').append('modal').mount(options, vm => vm.model.$showModal());
      else
          modal.model().$update(options).$showModal();
  }
docs: function for opening a modal inject this method to the root model