The affine evaluation map is a surjective homomorphism from the quantum toroidal ${ \mathfrak { gl}}_n$ algebra ${ \mathcal E}'_n(q_1,q_2,q_3)$ to the quantum affine algebra $U'_q\widehat{ \mathfrak { gl}}_n$ at level $\kappa$ completed with respect to the homogeneous grading, where $q_2=q^2$ and $q_3^n=\kappa^2$. We discuss ${ \mathcal E}'_n(q_1,q_2,q_3)$ evaluation modules. We give highest weights of evaluation highest weight modules. We also obtain the decomposition of the evaluation Wakimoto module with respect to a Gelfand-Zeitlin type subalgebra of a completion of ${ \mathcal E}'_n(q_1,q_2,q_3)$, which describes a deformation of the coset theory $\widehat{ \mathfrak { gl}}_n/\widehat{ \mathfrak { gl}}_{ n-1}$.
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