Graph rewriting is a powerful technique that requires graph pattern matching, which is an NP-complete problem. We present GrGen, a generative programming system for graph rewriting, which applies heuristic optimizations. According to Varró’s benchmark it is at least one order of magnitude faster than any other tool known to us. Our graph rewriting tool implements the well-founded single-pushout...

A hybrid network of evolutionary processors (an HNEP) is a graph where each node is associated with an evolutionary processor (a special rewriting system), a set of words, an input filter and an output filter. Every evolutionary processor is given with a finite set of one type of point mutations (an insertion, a deletion or a substitution of a symbol) which can be applied to certain positions o...

This paper describes Grrr, a prototype visual graph drawing tool. Previously there were no visual languages for programming graph drawing algorithms despite the inherently visual nature of the process. The languages which gave a diagrammatic view of graphs were not computa-tionally complete and so could not be used to implement complex graph drawing algorithms. Hence current graph drawing tools...

Rewriting is a common functionality in proof assistants, that allows to simplify theorems and goals. The set of equations to use in a rewrite step has to be manually specified, and therefore often includes rules which may lead to non-termination. Even in the case of termination another desirable property of a simplification set would be confluence. A well-known technique from rewriting to trans...

This paper introduces a generic and uniform approach to integrate different design languages for distributed systems in verification tools. It is based on Meseguer’s Rewriting Logic, hence transitions between the states of the respective system are modeled as (conditional) term rewriting steps modulo an equational theory. We argue that, for reasons of efficiency, it is intractable to admit arbi...

In this paper, we show that the SR transformation, a computationally equivalent transformation proposed by Şerbănuţă and Roşu, is a sound structure-preserving transformation for weakly-left-linear deterministic conditional term rewriting systems. More precisely, we show that every weakly-leftlinear deterministic conditional term rewriting system can be converted to an equivalent weakly-leftline...

We present a sound and complete logical system for deriving inclusions between graphs from inclusions between graphs, taken as hypotheses. Graphs provide a natural tool for expressing relations and reasoning about them. Here we extend this system to a sound and complete one to cope with proofs from hypotheses. This leads to a system dealing with complementation. Other approaches using pictures ...

We give a high-level overview of our recent results which extend and unify the lines of research initiated by Meseguer and Montanari under the motto “Petri nets are monoids”, and by Marti-Oliet, Meseguer and other authors in their linear logic axiomization of Petri nets. In particular, we investigate the use of rewriting logic, which was partially inspired by the two aforementioned approaches, ...

Gene assembly is an intricate biological process that has been studied formally and modeled through string and graph rewriting systems. Recently, a restriction of the general (intramolecular) model, called simple gene assembly, has been introduced. This restriction has subsequently been defined as a string rewriting system. We show that by extending the notion of overlap graph it is possible to...