Ventana software support forum

Hi;

I’m doing an optimization using multiple start: random. I would like to know how to make Vensim only use whole numbers (1,2,3 ...) and not with decimals, when it assigns values to the active parameters.My goal is to simplify the optimization process becouse i am using many parameters.

Another question is if there is any restriction in the number of active parameters to optimize.

Thanks for your help!

Hi

I do not think that there are restirictions to the number of parameters to optimize. But the time needed to optimize grows exponentially with the number of parameters.
The other drawback is that if you optimize with too many parameters it will be more difficult to really understand the reasons of the result and you will rely only on pure mathematical calculations and not on the understanding of the fundamental structure of the problem.
Joined a simplistic model that generates uniform integer random variables between 1 and 10.
Regards.
JJ

You can't force optimization on integers but if you take an input then use the INTEGER function on it and set ABS=.8 at the bottom right of the optimization setup dialog you should get a good approximation of this.