PolyCurve.ByjoinedCurves node issue

HI there!
I have two questions :slight_smile:

  1. I Would like to create floors with a node!
    This one is telling me " Warning :PolyCurve.ByJoinedCurves operation failed.
    Cannot make a PolyCurve from an empty list"
    As you can see my polycurve list are not empty so I don’t understand why this error message and so I cant generate floors!
  2. On Dynamo my shape is smooth but if we check on Revit, curves don’t follow this smooth shape and I don’t know why?!
    If you can give me some tips about that it will be really cool!
    Thank you verry much to the community180912rhino rhynamo dynamo version 1.....dyn|attachment (23.2 KB)


Actually, one of your inputs is an empty list :

Thank you Mellouze!:wink:
Problem solved for the first node.
However, the second node is telling me “Warning:Floor.ByOutlineTypeAndLevel operation failed.
The multiplicities of other interior knots must be at most degree - 2.
Parameter name: knots”
I saw this issue several times but I still don’t understand the meaning and what I have to do!
What is the tips to solve that please?
Thank you very much!