Same code different results in two computers

Hi Ning,

have you tried to run the same simulation on two computers using only *one*
core?

for correct order of engines, see
https://yade-dem.org/doc/user.html#base-engines

Jan

2012/11/29 ceguo <email address hidden>

> New question #215531 on Yade:
> https://answers.launchpad.net/yade/+question/215531
>
> Hi,
>
> I installed Yade-0.90 in two computers, one is my desktop, the other is a
> supercomputer. And I run same code on the two platforms I got different
> results.
>
> Besides, I found if I put NewtonIntegrator() before or after
> PeriTriaxController() in O.engines, I also got different results. So I am
> wondering where did these differences come from?
>
> Ning
>
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Hi Jan,

Thanks for the reply. I 'guess' NewtonIntegrator should be posed after PeriTriaxController, right? But I check some given example codes, I see someone puts NewtonIntegrator before the controller engine, which makes me confusing.

How can I specify using only one core for YADE simulation?

Ning

the number of threads should be 1 by default, but to be sure you can use

yade-trunk -j 1 yourScript.py

Jan

2012/11/29 ceguo <email address hidden>

> Question #215531 on Yade changed:
> https://answers.launchpad.net/yade/+question/215531
>
> Status: Answered => Open
>
> ceguo is still having a problem:
> Hi Jan,
>
> Thanks for the reply. I 'guess' NewtonIntegrator should be posed after
> PeriTriaxController, right? But I check some given example codes, I see
> someone puts NewtonIntegrator before the controller engine, which makes
> me confusing.
>
> How can I specify using only one core for YADE simulation?
>
> Ning
>
> --
> You received this question notification because you are a member of
> yade-users, which is an answer contact for Yade.
>
> _______________________________________________
> Mailing list: https://launchpad.net/~yade-users
> Post to : <email address hidden>
> Unsubscribe : https://launchpad.net/~yade-users
> More help : https://help.launchpad.net/ListHelp
>

Hi Jan,

I tried your suggestion, it seems the difference is not caused by multiple cores. The results are consistent but different for two computers.

Ning

Hi Bruno,

Thanks. I see your point. The two systems are different in version. I will upgrade the system and see if there is still any difference.

Ning

Thanks Chareyre, that solved my question.

Well, having different results is not bad in itself(*). Upgrading for this reason is overkilling but it's your time. ;)

(*) If it was bad, then which system would be giving the good result? The older one or the new one?!