## {3,7} hexiamond
h2.
angleunit(2*pi/7)
# the line below lets us specify internal angles
angleofs(pi)
distunit(edge(3,7))
unittile(1,3,1,4,1,3,1,4)
conway("(0 1)(2 3)(4 5)(6 7)")
sublines(1)
# warning: this one is "nonorientable"