Charm++ parallel programming system

[Tom Quinn <trq AT astro.washington.edu>]

What softening did you use?  Did you use periodic boundary conditions? 
What bucket size did you use?  With so few particles, I would guess that 
no multipole expansions were used: there would only be a couple of nodes 
in the tree, and they wouldn't be well separated.

It would be easier to track this down if you provided the param file, the 
initial condition file, and the command line parameters you used.

Tom Quinn       Astronomy, University of Washington
Internet:       
trq AT astro.washington.edu
Phone:          206-685-9009

On Wed, 11 May 2011, Shad Kirmani wrote:

> I generate 8-10 particles distributed uniformally(using rand) in space from
> (-5,-5) to (5,5). 
> I print out the forces calculated by ChaNGa and the order in which they are
> calculated.  I verify the force calculations by doing them manually(since
> the number of particle is small) and in the same order as ChaNGa. 
>
> I used the default parameters. I ran on a single treepiece. 
>
> Thanks for looking in to this.
> Shad Kirmani
> Graduate Student
> CSE PSU
>
> On Tue, May 10, 2011 at 12:27 PM, Pritish Jetley 
> <pjetley2 AT uiuc.edu>
>  wrote:
>       Could you give us a few more details? In particular, it would be
>       helpful to have the data set you are using, as well as the
>       parameters
>       passed to the code. Also, I'd like to know how you made the
>       comparison
>       of forces. Did you use the output of an N^2 computation as a
>       yardstick?
>
>       Thanks,
>       Pritish
>
>       P.S.: I have included cosmology-ppl in the list of recipients.
>       This is
>       the ChaNGa mailing list.
>
> On Tue, May 10, 2011 at 9:42 AM, Shad Kirmani 
> <sxk5292 AT cse.psu.edu>
> wrote:
> > Hello,
> > I have been using your ChaNGa code to calculate forces between the
> > particles.
> > When it comes to calculating forces there seems to be an issue.
> Particle to
> > node (using nodeBucketForce in gravity.h) is not being calculated to
> the
> > correct value. I am not being able to figure out why this is so.
> > We printed out the tree and verified that it is correct. We also
> verified
> > the Centre of Mass for each of the node to be correct.
> > Can anyone give me helpful pointers where I might be going wrong?
> > Thanks,
> > Shad Kirmani
> > Graduate Student,
> > CSE, Penn State
> > _______________________________________________
> > charm mailing list
> > 
> charm AT cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/charm
> >
> >
>
>
>
> --
> Pritish Jetley
> Doctoral Candidate, Computer Science
> University of Illinois at Urbana-Champaign