Re: endrun() was called with error level 8188 in density() function. (pure hydro simulation)

From: Volker Springel <volker_at_MPA-Garching.MPG.DE>
Date: Tue, 22 May 2007 13:53:39 +0200

Kim Do Gyun wrote:
>
> I made some initial conditions for testing pure hydro simulation.
> All particles are assigned to type "0", the gas particle, and each
> has velocity and internal energy information. For 2D simulation,
> all Z-axis values were set '0'.
>
> GADGET2 seemed to start with this IC well, but after some step,
> stoped itself with error level 8188.
>
> Here is the stdout result :
>
> +---------------------------------------------------------------------------+
>
> reading file `../ICs/kh.dat' on task=0 (contains 35078 particles.)
> distributing this file to tasks 0-0
> Type 0 (gas): 35078 (tot= 0000035078) masstab=0
> Type 1 (halo): 0 (tot= 0000000000) masstab=0
> Type 2 (disk): 0 (tot= 0000000000) masstab=0
> Type 3 (bulge): 0 (tot= 0000000000) masstab=0
> Type 4 (stars): 0 (tot= 0000000000) masstab=0
> Type 5 (bndry): 0 (tot= 0000000000) masstab=0
>
> reading done.
> Total number of particles : 0000035078
>
> allocated 0.0762939 Mbyte for ngb search.
>
> Allocated 3.73359 MByte for BH-tree. 64
>
> domain decomposition...
> NTopleaves= 106
> work-load balance=1 memory-balance=1
> domain decomposition done.
> begin Peano-Hilbert order...
> Peano-Hilbert done.
> Begin Ngb-tree construction.
> Ngb-Tree contruction finished
> task 0: endrun called with an error level of 8188
>
> +---------------------------------------------------------------------------+
>
>
> In the code, density.c,
>
> if(*SphP[i].Right == 0* && *SphP[i].Left == 0*)
> endrun(8188); /* *can't occur* */
>
> you can see the comment, "Can't occur", but it occured.
> That Right and Left variables are to be used for determining smoothing
> length. In the code, there are some mechanism to change that variables.
>
> Could someone explain what's going on here?
> SphP[i].Hsml is *NaN* here.

Hi,

I suspect the particle masses that you assigned in your initial
conditions file are all or partially 0. The code will then estimate a
zero mass density from the tree, and cannot estimate a valid guess for
the initial value of Hsml.

Volker


> (I even tried with smoothing length values in ICs, but got similar result)
>
>
>
>
> --
> ====================================
> Kim, Do Gyun
> Researcher
> Center for Space Astrophysics
> Yonsei University, Seoul, Korea
> TEL) 82-2-2123-4249
> FAX) 82-2-362-5136
> kdgcom_at_galaxy.yonsei.ac.kr <mailto:kdgcom_at_galaxy.yonsei.ac.kr>
>
Received on 2007-05-22 13:54:04