  In this paper we give Monk rules for Macdonald polynomials which are
analogous to the Monk rules for Schubert polynomials. These formulas are
similar to the formulas given by Baratta (2008), but our method of derivation
is to use Cherednik's interwiners. Deriving Monk rules by this technique
addresses the relationship between the work of Baratta and the product formulas
of Yip (2010). Specializations of the Monk formula's at $q=0$ and/or $t=0$
provide Monk rules for Iwahori-spherical polynomials and for finite and affine
key polynomials.
