As an example, try using a Hilbert curve to map {π, π} back onto R (and I mean π exactly, not π ± an infinitesimal). (There are, however, infinitely many mappi

As an example, try using a Hilbert curve to map {π, π} back onto R (and I mean π exactly, not π ± an infinitesimal). (There are, however, infinitely many mappings for {π, π ± ε} -> R and {π ± ε, π} -> R, such that ε is infinitesimal.)