topic Re: Repeat Random Streams giving different results in FlexSim Forum

Repeat Random Streams giving different results

thomas_jr — Wed, 06 May 2020 12:34:12 GMT

[ FlexSim 20.0.2 ]

Hi folks

I have noticed that the tokens in the processflow sometimes change ID between runs despite having Repeat Random Streams active, which makes it very difficult to identify bugs.

Is there something hidden in FlexSim that I should be aware of that may cause this kind of behaviour?

Best regards

Thomas

Re: Repeat Random Streams giving different results

joerg_vogel_HsH — Wed, 06 May 2020 12:54:31 GMT

Perhaps you have activated "Initialize random streams based on system time" in

File > Global Preferences > Environment

Re: Repeat Random Streams giving different results

thomas_jr — Wed, 06 May 2020 13:25:06 GMT

The field is unchecked in my FlexSim, but thanks for the answer!

Good to know for potential future applications.

Re: Repeat Random Streams giving different results

tanner_p — Wed, 06 May 2020 13:38:57 GMT

Hi @Thomas JR,

Do you have a model you could upload with this issue that we could take a look at? And are you seeing this issue in Experimenter or just in normal test runs of the model?

Re: Repeat Random Streams giving different results

thomas_jr — Wed, 06 May 2020 13:50:09 GMT

Hi @tanner.p

Unfortunately not. I'm working on a large healthcare model that contains sensitive data and other elements.

The issue appears in normal test runs. I've yet to dive into the Experimenter.

Re: Repeat Random Streams giving different results

Matthew_Gillespie — Wed, 06 May 2020 14:10:10 GMT

This page in the user manual goes over some of the things that can cause you model to not be repeatable:

https://docs.flexsim.com/en/20.0/BestPractices/ModelRepeatability/

Re: Repeat Random Streams giving different results

benjamin_w2 — Mon, 18 May 2020 17:22:08 GMT

Hi @Thomas JR, Was Matthew's comment helpful? Do you still need help with this?

Re: Repeat Random Streams giving different results

thomas_jr — Tue, 19 May 2020 11:02:00 GMT

Hi @Benjamin W2

Sorry, I did take a look at the section described, but I have yet to test if it resolves my problem.