public static KnowledgeLinkChartLayoutAlgorithm GetLinkChartLayout( 
   MapView mapView
)

{
  //var map = MapView.Active.Map;
  // a MapView can encapsulate a link chart IF it's map
  // is of type MapType.LinkChart
  var isLinkChart = map.MapType == MapType.LinkChart;
  // or use the following
  // var isLinkChart = map.IsLinkChart;

  var mv = MapView.Active;

  await QueuedTask.Run(() =>
  {
    if (isLinkChart)
    {
      // get the layout algorithm
      var layoutAlgorithm = mv.GetLinkChartLayout();

      // toggle the value
      if (layoutAlgorithm == KnowledgeLinkChartLayoutAlgorithm.Geographic_Organic_Standard)
        layoutAlgorithm = KnowledgeLinkChartLayoutAlgorithm.Organic_Standard;
      else
        layoutAlgorithm = KnowledgeLinkChartLayoutAlgorithm.Geographic_Organic_Standard;

      // set it
      mv.SetLinkChartLayoutAsync(layoutAlgorithm);

      // OR set it and force a redraw / update
      // await mv.SetLinkChartLayoutAsync(layoutAlgorithm, true);
    }
  });
}