Octagonal Loop in Octagonal Hole

Here we have an octagonal hole and an octagonal, annular loop. Such a geometry could be more efficiently modeled by making use of a sheet of class M, and triangulating the complementary (smaller in area) region to that shown below. However, if one needs to model this type of inductive element while including the surface resistance of the sheet, this can only be done using a sheet of class J (the default class).

using PSSFSS, Plots
sheet = polyring(s1=[1,0], s2=[0,1], a=[0.2, 0.5], b=[0.35, -25], sides=8, orient=22.5, units=cm, ntri=400)
p1 = plot(sheet, linecolor=:red, unitcell=true)
p2 = plot(sheet, linecolor=:blue, rep=(4,3))
plot(p1, p2, layout = (1,2), size=(800,400))