Introduction to parallel DEVS modelling and simulation.

DEVS is a popular formalism for modelling complex dynamic systems using a discrete-event abstraction. Main advantages of DEVS are its rigorous formal definition, and its support for modularity: models can be hierarchically nested. Thanks to these properties, DEVS frequently serves as a simulation "assembly language" to which models in other formalisms are mapped. This makes it possible to combine models in different formalisms together by mapping both to DEVS. This tutorial introduces the practical use of the Parallel DEVS formalism in a bottom-up fashion. We start from simple autonomous Atomic (i.e., non-hierarchical) DEVS models and increment up to Coupled (i.e., hierarchical) DEVS models. Each increment is illustrated with a minimal running example. The focus is on the practical use of DEVS modelling and simulation, though necessary theoretical foundations are interleaved. Examples are presented using Python-PDEVS, though the foundations and techniques apply to other DEVS simulation tools as well.