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How to store final time of simulation in a variable ?

Posted Dec 9, 2023, 5:46 a.m. EST Studies & Solvers Version 6.1 3 Replies

Olivier Louisnard
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I'm chaining two time-dependent simulations, the first one finishing on a stop condition and yielding the solution, say 'sol 1'.

I know how to create and start a new simulation starting from the final state of the latter.

What I don't manage to do is to record the value of the last time of simulation 1 and use it as the starting time of simulation 2. I've tried do define a variable tlast1 with the expression :

withsol( 'sol1', t, setind(t, 'last') )

It yields the correct value of final time, but repeated at each output time of 'sol1'. Thus, no surprise that when I try to use this quantity as the starting time of the second simulation, I get the error :

Unknown model parameter. - Parameter: tlast1 - Property: tlist (Output times) - Time dependent: Time Dependent

because tlast1 is not a scalar (by the way, why ?)

I've been deeply through the documentation and can't manage to find a way to do that. If anyone can help, thank you very much by advance.

3 Replies Last Post Mar 18, 2024, 3:14 p.m. EDT
Olivier Louisnard
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Posted: 11 months ago Dec 9, 2023, 5:48 a.m. EST

Sorry, I forgot to join a basic MPH file reproducing the problem. Here it is.

Sorry, I forgot to join a basic MPH file reproducing the problem. Here it is.

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Busuyi Adebayo
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Posted: 8 months ago Mar 18, 2024, 2:27 p.m. EDT
Updated: 8 months ago Mar 18, 2024, 2:20 p.m. EDT

Hi Olivier,

Did you mamage to solve this problem? I am facing similar situation.

Thank you!

Hi Olivier, Did you mamage to solve this problem? I am facing similar situation. Thank you!
Edgar J. Kaiser Certified Consultant
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Posted: 8 months ago Mar 18, 2024, 3:14 p.m. EDT

Olivier,

your issue is that the time list in the time dependent study is not accepting variables, only parameters. This is for a reason because variables might produce cumbersome conditions for a solver. A workaround might be to run a model method at the end of study 1 that sets a parameter in the parameter list to the tlast1 value and you can use this parameter then in study 2. I never did that by myself in such a case but I think it should be feasible. I successfully did write methods that create and set parameters for other purposes, e.g. geometry where variables can't be used as well.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Olivier, your issue is that the time list in the time dependent study is not accepting variables, only parameters. This is for a reason because variables might produce cumbersome conditions for a solver. A workaround might be to run a model method at the end of study 1 that sets a parameter in the parameter list to the tlast1 value and you can use this parameter then in study 2. I never did that by myself in such a case but I think it should be feasible. I successfully did write methods that create and set parameters for other purposes, e.g. geometry where variables can't be used as well. Cheers Edgar

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