RealySt: A C++ Tool for Optimizing Reachability Probabilities in Stochastic Hybrid Systems

This paper presents the open-source C++ tool RealySt for effectively computing optimal time-bounded reachability probabilities for subclasses of hybrid automata extended with random clocks. The tool explicitly resolves the underlying nondeterminism and computes reachable state sets exactly. The error of the computed results solely stems from the multi-dimensional integration. The architecture of RealySt is extensible and allows to easily integrate other classes of hybrid automata extended by random clocks. RealySt relies on the HyPro library to perform flowpipe construction, and on GSL for multi-dimensional integration.