[FLASH-BUGS] possible bugs in Poisson routines

[Artur Gawryszczak]

Hello,

On Thursday 07 August 2003 23:12, Paul Ricker wrote:
> The dust collapse problem requires isolated boundary conditions, which
> are not supported for multigrid in 2D Cartesian coordinates.  What
> boundary conditions did you use for the 2D/3D multigrid case? 

I'm using `grav_boundary_type = "isolated"' in every run. Maybe this isn't 
supported, but both 2D and 3D setups does not complain about that. I made 
integrations once more (third or fourth time) and found the missing factor. 
I'm sorry about the mess.

> For multipole, the problem is spherically symmetric, so you shouldn't
> need to use such high mpole_lmax values.  I suspect the problem in
> this case is that, because of the high power of r for high multipole
> order, errors in the computation of moments near the center are
> leading to force errors there.

Well, this was just an experiment. If it produces strange results in simple 
case, I'd rather not trust it and use multigrid submodule.

-- 
Best Regards,
        Artur