Round equivalent to Smooth ceil node

Hi there,
I noticed the material function ‘smooth ceil’ inside the material editor but cannot seem to find a smooth version for ‘Round’ and / or ‘floor’.
Does anyone know these even exist? Or how to create them?
Best regards!

Did you ever manage to get an answer?

nope, but I am much smarter now, so I can think I can figure this out myself, although I didn’t need it anymore, so pushed it back into limbo.