[Users] adding levels to Carpet parameter file

Bernard Kelly bernard.j.kelly at nasa.gov
Mon Oct 11 14:07:50 CDT 2010


  Hi Erik.

Thanks for looking it over. I realise that time_refinement_factors can 
be changed to avoid halving the timesteps, but for now, I wanted to be 
minimalist.

But can you then tell me why the newer version crashes? Why is 
NaNChecker now finding NaNs it didn't before?

Bernard

On 10/11/10 2:16 PM, Erik Schnetter wrote:
> Bernard
>
> Your changes look fine.
>
> You are changing also the maximum number of refinement levels. This is
> not necessary; I would leave it the same, but it shouldn't make a
> difference.
>
> You are not changing dtfac. dtfac is the CFL factor on the coarsest
> grid. Since you add new, coarser levels without time refinement (this
> is the additional "1" you introduced to the time_refinement_factors
> list), you are modifying the CFL factor on the finest grid; if I get
> my arithmetic right, it now takes time steps twice as large as before.
>
> This is admittedly a trapdoor that is difficult to avoid. It is
> unfortunate that Cactus wants you to set the coarse grid parameters
> (grid spacing and CFL factor), whereas we encounter the CFL limit on
> the finest grid. I assume one could check the CFL factor on all levels
> in thorn CactusBase/Time; however, this is not implemented.
>
> -erik
>
> On Mon, Oct 11, 2010 at 12:52 PM, Bernard Kelly
> <bernard.j.kelly at nasa.gov>  wrote:
>>   Hi all.
>>
>> I'm trying something very simple -- running the "qc0-mclachlan" parameter
>> file
>> (specifically, the version found in Cactus/par after checking out
>> EinsteinToolkit
>> -- the version in Cactus/repos/McLachlan/par seems almost identical).
>>
>> After getting rid of one thorn I can't check out anyway
>> (LSUThorns/SummationByParts),
>> the parfile seems to run OK. I've since modified it by switching to a full
>> x-domain,
>> removing the Pi-symmetry, and moving the punctures out a bit. That all seems
>> to work.
>>
>> But now I'm getting stuck trying to modify it in a simple way -- enlarging
>> the grid
>> while adding refinement levels "on the outside". Diffing my new "bad"
>> parfile with the
>> old "good" one yields the differences below. I'm attaching the bad parfile
>> here also.
>>
>> Can anyone tell me where I've gone wrong, please? Are there assumed
>> parameter values never set in the test parfile?
>>
>> Thanks,
>>
>> Bernard
>>
>> P.S. The errors all seem to be from NaNChecker. Here's the first printed
>> sample:
>>
>> WARNING level 1 in thorn NaNChecker processor 29 host borgh098.prv.cube
>>   (line 875 of
>> /gpfsm/dnb31/bjkelly1/Cactus/configs/mcl/build/NaNChecker/NaNCheck.c):
>>   ->  There were 35 NaN/Inf value(s) found in variable 'ML_BSSN::phi' (NaNmask
>> bitfield 0)
>>
>>
>> ---------- results of diffing "good" (<) and "bad" (>) parfiles
>> -----------------
>>
>> 47c47
>> <  Carpet::max_refinement_levels          = 10
>> ---
>>> Carpet::max_refinement_levels          = 11
>> 99,100c99,100
>> <  CoordBase::xmin = -120.00
>> <  CoordBase::ymin = -120.00
>> ---
>>> CoordBase::xmin = -240.00
>>> CoordBase::ymin = -240.00
>> 102,107c102,107
>> <  CoordBase::xmax = +120.00
>> <  CoordBase::ymax = +120.00
>> <  CoordBase::zmax = +120.00
>> <  CoordBase::dx   =    2.00
>> <  CoordBase::dy   =    2.00
>> <  CoordBase::dz   =    2.00
>> ---
>>> CoordBase::xmax = +240.00
>>> CoordBase::ymax = +240.00
>>> CoordBase::zmax = +240.00
>>> CoordBase::dx   =    4.00
>>> CoordBase::dy   =    4.00
>>> CoordBase::dz   =    4.00
>> 170c170
>> <  CarpetRegrid2::num_levels_1            =  7
>> ---
>>> CarpetRegrid2::num_levels_1            =  8
>> 172,177c172,178
>> <  CarpetRegrid2::radius_1[ 1]            =  64.0
>> <  CarpetRegrid2::radius_1[ 2]            =  16.0
>> <  CarpetRegrid2::radius_1[ 3]            =   8.0
>> <  CarpetRegrid2::radius_1[ 4]            =   4.0
>> <  CarpetRegrid2::radius_1[ 5]            =   2.0
>> <  CarpetRegrid2::radius_1[ 6]            =   1.0
>> ---
>>> CarpetRegrid2::radius_1[ 1]            = 128.0
>>> CarpetRegrid2::radius_1[ 2]            =  64.0
>>> CarpetRegrid2::radius_1[ 3]            =  16.0
>>> CarpetRegrid2::radius_1[ 4]            =   8.0
>>> CarpetRegrid2::radius_1[ 5]            =   4.0
>>> CarpetRegrid2::radius_1[ 6]            =   2.0
>>> CarpetRegrid2::radius_1[ 7]            =   1.0
>> 180c181
>> <  CarpetRegrid2::num_levels_2            =  7
>> ---
>>> CarpetRegrid2::num_levels_2            =  8
>> 182,187c183,189
>> <  CarpetRegrid2::radius_2[ 1]            =  64.0
>> <  CarpetRegrid2::radius_2[ 2]            =  16.0
>> <  CarpetRegrid2::radius_2[ 3]            =   8.0
>> <  CarpetRegrid2::radius_2[ 4]            =   4.0
>> <  CarpetRegrid2::radius_2[ 5]            =   2.0
>> <  CarpetRegrid2::radius_2[ 6]            =   1.0
>> ---
>>> CarpetRegrid2::radius_2[ 1]            = 128.0
>>> CarpetRegrid2::radius_2[ 2]            =  64.0
>>> CarpetRegrid2::radius_2[ 3]            =  16.0
>>> CarpetRegrid2::radius_2[ 4]            =   8.0
>>> CarpetRegrid2::radius_2[ 5]            =   4.0
>>> CarpetRegrid2::radius_2[ 6]            =   2.0
>>> CarpetRegrid2::radius_2[ 7]            =   1.0
>> 190c192
>> <  CarpetRegrid2::num_levels_3            =  7
>> ---
>>> CarpetRegrid2::num_levels_3            =  8
>> 192,197c194,200
>> <  CarpetRegrid2::radius_3[ 1]            =  64.0
>> <  CarpetRegrid2::radius_3[ 2]            =  16.0
>> <  CarpetRegrid2::radius_3[ 3]            =   8.0
>> <  CarpetRegrid2::radius_3[ 4]            =   4.0
>> <  CarpetRegrid2::radius_3[ 5]            =   2.0
>> <  CarpetRegrid2::radius_3[ 6]            =   1.0
>> ---
>>> CarpetRegrid2::radius_3[ 1]            = 128.0
>>> CarpetRegrid2::radius_3[ 2]            =  64.0
>>> CarpetRegrid2::radius_3[ 3]            =  16.0
>>> CarpetRegrid2::radius_3[ 4]            =   8.0
>>> CarpetRegrid2::radius_3[ 5]            =   4.0
>>> CarpetRegrid2::radius_3[ 6]            =   2.0
>>> CarpetRegrid2::radius_3[ 7]            =   1.0
>> 206c209
>> <  Carpet::time_refinement_factors        = "[1,1,2,4,8,16,32,64,128,256]"
>> ---
>>> Carpet::time_refinement_factors        = "[1,1,1,2,4,8,16,32,64,128,256]"
>> ----------------------------------------------------------------
>>
>> --
>> -----------------------------------------------
>> Bernard J. Kelly
>>
>> NASA Goddard Space Flight Center, Code 663
>> 8800 Greenbelt Road
>> Greenbelt, MD 20771, U.S.A.
>>
>> phone: +1 (301) 286-7243
>> -----------------------------------------------
>>
>>
>> _______________________________________________
>> Users mailing list
>> Users at einsteintoolkit.org
>> http://lists.einsteintoolkit.org/mailman/listinfo/users
>>
>>
>
>


-- 
-----------------------------------------------
Bernard J. Kelly

NASA Goddard Space Flight Center, Code 663
8800 Greenbelt Road
Greenbelt, MD 20771, U.S.A.

phone: +1 (301) 286-7243
-----------------------------------------------



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