sub-sub-submodekls

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LAUJJL
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Joined: Fri May 23, 2003 10:09 am
Vensim version: DSS

sub-sub-submodekls

Post by LAUJJL »

Is it possible to have multiple levels of sub models?
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Re: sub-sub-submodekls

Post by Administrator »

Not yet. What you can do is add any sub-sub models to the parent model.
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LAUJJL
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Posts: 1421
Joined: Fri May 23, 2003 10:09 am
Vensim version: DSS

Re: sub-sub-submodekls

Post by LAUJJL »

One of the main interests (at least for me) is to split a big model into smaller ones to make it easier to test them. Unfortunately, you can only test the sub-models mathematically, testing that there is no equation error. The problem comes from the necessity to find a value for some variables that have become constants in the sub-model and that value can be incoherent with the values given to some parameters that can normally influence the variable in another sub-model or in the main model. Forcing values to constants that are normally variables will generate behaviours that are impossible to predict and are probably unrealistic. In my model it was possible to avoid that pitfall by building multiple sub-models to make sure that when simulating any sub-models, it was never necessary to change a variable into a constant, being always calculated in the sub-model or in a sub-sub-model. To resume sub-models may influence parents but parents do not influence sub-models. The influence must be upward. JJ
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