  Chirped sinosoids and interferometric phase plots are functions that are not
periodic, but are the composition of a smooth function and a periodic function.
These functions functions factor into a pair of maps: from their domain to a
circle, and from a circle to their codomain. One can easily imagine replacing
the circle with other phase spaces to obtain a general quasiperiodic function.
This paper shows that under appropriate restrictions, each quasiperiodic
function has a unique universal factorization. Quasiperiodic functions can
therefore be classified based on their phase space and the phase function
mapping into it.
