  This is a paper about $c$-functions and Macdonald polynomials. There are
$c$-function formulas for $E$-expansions of $P_\lambda$ and $A_{\lambda+\rho}$,
principal specializations of $P_\lambda$ and $E_\mu$, for Macdonald's constant
term formulas, and for the norms of Macdonald polynomials. Most of these follow
from the creation formulas for Macdonald polynomials, providing alternative
proofs to several results from Macdonald (2003). In addition, we prove the
Boson-Fermion correspondence in the Macdonald polynomial setting and the Weyl
character formula for Macdonald polynomials.
