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How to stop a runaway simulation?
Posted 11.08.2010, 11:15 GMT-4 7 Replies
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I am running simulations automated with matlab scripting. Sometimes the simulations run away (do not converge) and last for ever with a extremly small time step. In such situations one usually hits the stop button in the solution progress window, but in an automated run you can't.
I guess it could be done with the Stop Condition in the 'Solvers Parameters - Time Stepping - Use Stop Condition' field.
There I could use the current or last time step size and set a limit to it.
But how can I access the current (or last) Stepsize ? Is there a variable I can use?
Thanks for any ideas,
Martin
Hello Martin Suter
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Could someone give an answer?
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ctrl + pause/break
Using script - check the documentation of a function that you use... Try to find where "the evaluation of convergance" is calculated and write proper condition..
Best regards,
Rafał Piotuch
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I don't quiet see what you mean!
Could you please be more precise?
Cheers
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sure:) Hope you use Matlab to solve problem, else I don't know how to help you:)
So.. If you use Matlab it is easy to stop simulation manualy- just press ctr+pause/break and the simulation stops after some time - but for sure you want to stop simulation automaticly, without any human control...
When you solve sth. using for example femtime function.. read documentation of such function and read script of this function - there must be a "place" in code that refers to convergance calculation... So there must be a variable that stores current step_size.. If you will write in pseudo code:
if (step_size<0.0001) then
%the function return sth, so it should be stopped or proper value should be returned.
return(0);
it should be working.
So that's all.
Rafał Piotuch
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