ssys: Exact algebraic recasting of ODE models into S-system or GMA form

Abstract

ssys is a Python package for exact algebraic recasting of supported ODE models into S-system or Generalized Mass Action form. It reads Antimony and SBML models, introduces auxiliary variables through symbolic lifting, and validates transformed systems using symbolic, numerical, and trajectory-based checks. The package provides command-line workflows, notebook generation, and benchmark evidence across curated models and BioModels examples, making classical power-law recasting practical for reproducible systems biology modeling.