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A dynamic and flexible way to extend a model, views are a powerful tool in the whatIf? suite.
Models, especially once populated with data, are fairly rigid. Modifying any working model requires changing the design and reloading data. Views provide a mechanism for extending the model either through preprocessed input data, additional analysis of output data and even implementing feedback loops in the model's logic.
Suppose you had a model which had a control variable specifying exogenously the market share for new vehicles over time. There are many ways to create that data and one must have been used to load the original model. If you found a new algorithm for determining that market share based on something inside the model, something totally external or some mix of these, then a view could be written to implement this algorithm and feed it into the model as the new market share. Essentially you have extended the model's scope but have taken on the work of actually modifying the model. Of course the model can be changed later to encapsulate the new logic in the model itself but it doesn't need to.
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Part of the design process is deciding what should be part of the rigid structure of the model and what should be dynamic and implemented by views.
In the whatIf? platform views are the method used for interacting dynamically with the model. Views are used to import and export data, to mediate interaction with the model, do analysis and display it to the user, do iterative runs of the model to converge on parameter settings and every combination of these.
Paragraph talking about ability to overlay behaviour or control structure on top of our physical substrate built right into the model
Manufacture instantiation of data in views instead of the structure of the model to give extra flexibility
Display views are read only views into the model which do not change any model data but instead pull data from the model. These can be considered as reporting view. Here are some uses of display views: