Polygon PeriodicBC Problem

[siwuxei]

Hi Lulu,

Thank you for the code library you developed, it has been very helpful to me.

I am currently working on solving a problem that involves periodic boundary conditions, as shown in the diagram. The top and bottom boundaries should be periodic (the yellow lines indicate the boundaries), meaning that the output of the equation should be the same at the top and bottom boundaries.

In this example, the top and bottom boundaries are defined using Polygons. When I try to use the built-in PeriodicBC method directly, I encounter the error "NotImplementedError: Polygon.periodic_point to be implemented."

Do you have any suggestions? Thank you for your prompt response! Thanks!