As mentioned in another post, as a consequence of Mittag-Leffler's theorem combined with the Weierstrass factorization theorem, after reducing to the common denominator, any meromorphic function can be expressed as
$$f(z) = e^{g(z)}\prod_k(z-z_k)^{n_k} \tag{1}\label{1}$$
where $n_k > 0$ ($n_k<0$) denotes the multiplicity of a zero (pole) at $z_k$ and $g(z)$ is an entire function.
This can be reformulated and generalized into
$$\begin{align} f(z) &= \exp\left[g(z) + \sum_k n_k\ln(z-z_k)\right] \\ &\to \exp\Big[g(z) + \underbrace{\int_\mathbb C n(y)\ln(z-y)\,dy}_{=(n\ast_\mathbb C\ln)(z)}\Big] \tag{2}\label{2} \end{align}$$
where $n(z)$ is a strictly integer-valued distribution for meromorphic functions, but could in general also be something else, e.g. a meromorphic function itself. Due to its origin I'd like to refer to $\eqref{2}$ as the Weierstrass-Mittag-Leffler-Transformation (or WeMiLe-Transformation, if you allow for that acronym). So now my question is
How can the transformation $\eqref{2}$ be inverted?
For a meromorphic $f(z)$ with finitely many zeros of finite order that inversion is obviously $n(y) = \sum_k n_k \delta(y-z_k)$ and $g(z)=\ln\big[f(\zeta)/\prod_k(\zeta-z_k)\big]$ for any $\zeta\in\mathbb C\backslash\{z_k\}$, i.e. one has to determine all zeros and poles, but what about non-meromorphic $f(z)$, e.g. what about $f(z)=\delta(z)$?
\labelscrews up MathJax. Of course, I should have remembered that... – Tobias Kienzler Oct 23 '14 at 19:21