AtomicStateSystem

[maxitg]

Changes

• Implements AtomicStateSystem.
• Implement by simply calling MultisetSubstitutionSystem, so has similar limitations.

Comments

• This is similar to what the MultiwaySystem resource function does.
• Does not support multiple branchlike outputs per event, as the multiset system does not support it. Can be added with a new head (e.g., Branchlike[...] or AlternativeOutputs[...]).
• I added "InputIndex" as an ordering function, which is redundant as "InputTokenIndices" and "SortedInputTokenIndices" do the same thing for the atomic system. They just seem awkward if there is only one input token by design, so I added "InputIndex". Let me know what you think.
• This is ready for review, but it requires the MultisetSubstitutionSystem docs to be merged first.

Examples

• Multiple rules are required for branching at the moment:

In[] := #["ExpressionsEventsGraph", VertexLabels -> Placed[Automatic, After]] & @
  SetReplaceTypeConvert[{WolframModelEvolutionObject, 2}] @
    GenerateMultihistory[AtomicStateSystem[{n_ :> n + 1, n_ :> n - 1}],
                         {"MaxGeneration" -> 4},
                         None,
                         EventOrderingFunctions[AtomicStateSystem],
                         {}] @ 0

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