The data flow paradigm has established itself as a powerful approach to machine learning. In fact, it isalso very powerful for computational physics, although it is not used as much in the field. One of thecomplications is that physical models are much less homogeneous compared to ML, which makestheir description a complicated task. In this paper we present a syntax analyzer for the GNAframework. The framework is designed to build mathematical models as lazy evaluated directedacyclic graphs. The syntax analyzer introduces a way for a concise description and configuration ofthe models using math-like syntax, providing scalability and branching. The goal of the project is todevelop a technique and a software to facilitate a generic analysis and input data descriptioncompatible with multiple backends, e.g. GNA.