GQR: A Fast Solver for Binary Qualitative Constraint Networks

Qualitative calculi are constraint-based representation formalisms that allow for efficient reasoning about continuous aspects of the world with inherently infinite domains, such as time and space. GQR (Generic Qualitative Reasoner) is a tool that provides reasoning services for arbitrary binary qualitative calculi. Given qualitative information expressible in a qualitative calculus, GQR checks whether this information is consistent w.r.t. the calculus definition. GQR employs stateof-the-art techniques in both qualitative and constraint reasoning, such as heuristic search and usage of known tractable subclasses. In contrast to specialized reasoners, it offers reasoning services for a variety of calculi known in the literature, which can be defined in a simple specification language. The main focus in the design and implementation of GQR is to provide a generic and extensible solver that preserves efficiency and scalability.