For $Y(b) = \text{thing}_1$, after a transform to another domain $Y(a)=\text{thing}_2$ , is there $Y(a,b)= \text{thing}_3$?
where $\text{thing}_3$ is related to $\text{thing}_1$ and $\text{thing}_2$ ?
More clarification:-
Ok, if I have a function in time say $Y(n) = u(n)$; after moving to $Z$-domain it will be $Y(Z)= \frac{z}{(z-1)}$, is there some way I can make a new function $Y(n,Z)$ = something that changes to n and Z ?
Edit 2:
I want if $(n =0)$ in $Y(n,Z) = Y(Z)$ and vice versa