topic Re: Set random seed in 3D model in FlexSim Forum

Set random seed in 3D model

jyhjeng_d2 — Tue, 21 Feb 2023 03:53:24 GMT

[ FlexSim 22.0.1 ]

I used a different random seed to see its influence on the statistics in the queue length in a simple queueing model. However, I could not set the seed. Instead, I looked at the Q&A, and they suggested I use toolbox > Modeling Logic > Model Trigger > On Reset.

However, my toolbox did not have such an option.

How could I change the random seed for the source?

Here is my flexsim file.Primer_1-1A.fsm

Re: Set random seed in 3D model

joerg_vogel_HsH — Tue, 21 Feb 2023 06:33:10 GMT

@Jyhjeng D2, what kind of license do you use? You need a licensed version of FlexSim to get randomized results. A Demo version called express license won’t be able to allow all feature you describe that you are missing. https://answers.flexsim.com/articles/65811/flexsim-features-by-license-type.html

Re: Set random seed in 3D model

jason_lightfoot_adsk — Tue, 21 Feb 2023 13:06:13 GMT

The option would still be there but yield this message when selected:

Re: Set random seed in 3D model

jason_lightfoot_adsk — Tue, 21 Feb 2023 13:10:35 GMT

Change the random seeds for the streams using the experimenter by either:

Running an experiment and looking at the differing results for each replicaiton
Go to the advanced tab of the experimenter and change the replication to use for your manual run:

Make sure you use a non-zero stream number in any stochastic expression (usually best to use getstream(current) or getstream(activity) )

There is another option which is to disable the 'repeat streams' option under the stochastics menu - this has limited use since, should you find anything interesting in terms of results or detecting bugs, you will not be able to replicated it.

Re: Set random seed in 3D model

jyhjeng_d2 — Wed, 22 Feb 2023 02:25:07 GMT

Got it. I used a trial version. That is why the random seed did not work. Thanks.