Model Definition

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Model Definition

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This section contains a quick overview of the elements used to define a model with Ventity.   Much more detail is provided in the section Defining a Model.

 

Ventity is used to simulate the behavior of complex systems.  A system typically consists of different types of things that interact to produce system behavior.  In Ventity, each type of system member is referred to as an entity type.  Entity types can represent organizations cities, buildings, resources, projects, shipping, and many other types of objects, plans, or concepts.

 

Ventity is based on System Dynamics principles, with the state of the system and each entity based on stocks and flows.  Ventity also supports auxiliary variables, constant parameters, and lookup tables.  Ventity support Euler integration between time steps in a simulation.  Ventity supports both relative time and calendar time.

 

Ventity provides additional features:

 

-        Attributes are string variables that are used to identify entities, indicate group membership, provide access to other entities, or keep track of status

-        References provide access to other entities using one or more attribute value

-        Collections are automatically maintained that contain all active entities of each type

-        Sub-collections are created for groups of entities that share the same value for one or more attributes

-        Actions are procedures which applied between the regular integration time steps.  Actions can create or delete entities.or make other state changes.

-        Triggers can be added to entities, collections, sub-collections, or actions that invoke actions based on specified criteria

-        MACROs are reusable chunks of model logic that are invoked with Function calls

-        Components are reusable chunks of model logic that can be inserted into multiple entities or multiple times into the same entity