Are there things that need to be done to have a simulation that repeats time after time?

[Vaillancourt]

Hello!

Say I have  X vehicles simulated, and every simulation run, each vehicle receives the exact same input as the previous simulation run; can I expect to have the same simulation result, or there are things that prevent this? 

Assume that:

- I'll repeat this on the same system, with the same executable

- I have hacked the int dRand() function to always return the same value (0)

Thanks!

- Alexandre Vaillancourt

[Oleh Derevenko]

You can assign a specific seed for the dRand, you don't need to disable it.
If you use single-threaded mode then your simulation should yield the same results each time.

Oleh Derevenko

-- Skype with underscore

 

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Subject: [ode-users] Are there things that need to be done to have a simulation that repeats time after time?

 

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[Vaillancourt]

You can assign a specific seed for the dRand, you don't need to disable it.

Yes, you're right; we're doing this normally but I wanted to make sure and "isolate" this aspect of the issue.

 

If you use single-threaded mode then your simulation should yield the same results each time.

Okay, we don't explicitly enable multi-thread right now and so it's not the issue.

Thanks for the answer, I'll keep digging!

- Alexandre

[Vaillancourt]

I confirm that this appeared to be an issue with our code, not ODE's.

Thanks!

- Alexandre Vaillancourt