How can I join the option of ellipse? Is there any open source?
It has not been implemented in Dynamo for Civil 3D, along with many other object types.
What are you looking to do with the ellipse type?
2 Likes
Because many people use ellipses to draw circle types, resulting in 2-3 thousand ellipse-type circles that cannot be defined 
Select everything and filter by object type comparison and boolean mask.
Or utilize List.RemoveIfNot.
1 Like