public Result Execute(
ExternalCommandData commandData,
ref string message,
ElementSet elements)
{
UIApplication app = commandData.Application;
UIDocument uidoc = app.ActiveUIDocument;
_doc = uidoc.Document;
//RunBenchmark();
Element wall = Util.SelectSingleElementOfType(
uidoc, typeof( Wall ), "a wall", true );
GetInstancesIntersectingElement( wall );
return Result.Succeeded;
}