Thanks for the quick response!
But what about in theory, when we have such a situation?
[code]eo = SplineGeometry()
pnts = [(0, 0), (0.4999, 0), (0.4999, 1), (0, 1), (0.5, 0), (1, 0), (1, 1), (0.5, 1)]
pind = [ geo.AppendPoint(*pnt) for pnt in pnts ]
geo.Append([‘line’,pind[0],pind[1]],leftdomain=1,rightdomain=0,bc=“bottom”)
geo.Append([‘line’,pind[1],pind[2]],leftdomain=1,rightdomain=0,bc=“interface”)
geo.Append([‘line’,pind[2],pind[3]],leftdomain=1,rightdomain=0,bc=“top”)
geo.Append([‘line’,pind[3],pind[0]],leftdomain=1,rightdomain=0,bc=“left”)
geo.Append([‘line’,pind[4],pind[5]],leftdomain=2,rightdomain=0,bc=“bottom”)
geo.Append([‘line’,pind[5],pind[6]],leftdomain=2,rightdomain=0,bc=“right”)
geo.Append([‘line’,pind[6],pind[7]],leftdomain=2,rightdomain=0,bc=“top”)
geo.Append([‘line’,pind[7],pind[4]],leftdomain=2,rightdomain=0,bc=“interface”)[/code]
https://ngsolve.org/media/kunena/attachments/1238/gluing.py
Attachment: gluing.py