amusecode
remove set_acceleration from gd.py
propose to remove set_acceleration from the gravitational dynamics interface..its hardly implemented anywhere and I am not sure why it is there (no consistent use case..)
there could be a a use of for setting an external acceleration of some sort..but then you would name and implement it differently..
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This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 28 days if no further activity occurs. Thank you for your contributions.
This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 28 days if no further activity occurs. Thank you for your contributions.
This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 28 days if no further activity occurs. Thank you for your contributions.
This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 28 days if no further activity occurs. Thank you for your contributions.
Hi, I find this interesting because Bonsai is such a high-performance code, I keep asking myself why is it not better documented with sample scripts et al. ; I have not been able to "parse" bonsai as an integrator with an external potential through a bridge, although this works just fine with many integrators : Octgrav, BHTree, Phigrape, Ph4, .. but I guess since Bonsai is 100% GPU, that it does not stop-go to read the external field. The resuls - always the same - is that the system dissolves on a dynamical timescale. I was not aware of the set_acceleration() method, and do not know how to implement this : anyone with an example .. ? In general Amuse is a superior environment to compare results and trying different approaches, so having a Bonsai with embedded systems would be very useful in fact. cheers, cmb.
Moved the comment to a different issue. set_acceleration methods in Bonsai do set the acceleration, however it's immediately overwritten so I don't see the point of having them...
Hi Steven, waw that was a quick reply .. It may well be that I am messing up the units somehow, but why should the
approach be different for Bonsai, compared to (say) Octgrav or Ph4 ? My script is a simple embedding of a galactic disc
(of stars) in a frozen external (halo) potential. The disc is built with Agama, but that is not important I don't think. I provide
a converter, i.e. the same set of units used to create the stellar disc, and then embed that disc in the halo. As I say, I used
Ph4, .. Phigrape (gpu) , using GPU's - for Octgrav, Phigrape - or mpi. It works fine, but performances are not great with N ~ 2^17
= 131k stars or more ; Bonsai handles easily up to 2^19 ~ 400k stars in a fraction of the time (it's actually 15 minutes of runtime
compared to 4h for the other codes). But the Bonsai integrator simply thinks that the disc is isolated so it is missing a large halo
potential, as used by Agama to integrate [individual] orbits. The disc dissolves quickly, when it should be in equilibrium ;(
Cheers,
Chris B.
Christian Boily Tel.: work: +33-(0)3.68.85.24.36 Observatoire astronomique home: 11, rue de l'Universite FAX : +33-(0)3.68.85.24.17 Strasbourg F-67000 @.*** France urlhttp://www.rzuser.uni-heidelberg.de/~s17
On 9/14/23 15:18, Steven Rieder wrote:
Moved the comment to a different issue. set_acceleration methods in Bonsai do set the acceleration, however it's immediately overwritten so I don't see the point of having them...
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