Test randomization functions

SDXorg / test-models

A collection of System Dynamics models implemented in various environments with a canonical output

MIT License

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Test randomization functions #32

Open JamesPHoughton opened 8 years ago

JamesPHoughton commented 8 years ago

Test the following Vensim functions:

EXPRND
LOGNORMAL
RANDOM NORMAL
POISSON
RANDOM UNIFORM

We may have to be clever about how we do it. Maybe taking sums of large numers of samples with different parameters?

JamesPHoughton commented 8 years ago

The caching issue is complex here, as it doesn't depend on the stock. The value of the call to rand should probably not be cached, as that would introduce artificial covariance. But the functions that contain the call should absolutely be cached, so that they have the same value for any of their downstreams...

Should write a variable that uses the rand, and is called in two different elements, and then make sure they are the same, which would not be the case if the full tree was called each time...