Modeling
\[\begin{aligned}
\hspace{5em} && \textit{All models are wrong. Some are useful. (George Box)}
\end{aligned}\]
We have seen different approaches in modeling discrete event systems (DES) for simulation. Most of them are limiting in some way. But DiscreteEvents provides a simple, yet versatile and powerful grammar for combining them.
- Sampling: for periodic actions,
- Event scheduling: for scheduling single events at given times or under given conditions,
- Activities: for expressing an event and the time until another event as an overlapping activities in a system,
- Processes: for expressing entities with typical sequences of events interacting in a system,
- State Machines: for expressing entities reacting differently to events based on their current state,
- Actor systems: for representing systems consisting of multiple nested and parallel interacting components.
The following examples show how those different approaches to modeling DES can be employed and combined.