[Users] problems with AHFinderDirect

[Erik Schnetter]

On Thu, Jun 14, 2012 at 8:40 AM, Ian Hinder <ian.hinder at aei.mpg.de> wrote:
>
> On 14 Jun 2012, at 13:53, Eloisa Bentivegna wrote:
>
>> On Jun 14, 2012, at 12:01 PM, Vassilios Mewes wrote:
>>
>>> Hello all,
>>>
>>> when using the AHFinderDirect thorn in a simulation of a relativistic wind past a TOV neutron star, i get the following error message:
>>>
>>> INFO (AHFinderDirect): proc 0: searching for horizon 1/1
>>>  [1mWARNING level 0 in thorn AHFinderDirect processor 0 host permeability.daa.uv.es
>>>  (line 78 of /Users/vass/programs/Cactus/arrangements/EinsteinAnalysis/AHFinderDirect/src/jtutil/error_exit.cc):
>>>  -> [0m ***** row_sparse_Jacobian__UMFPACK::solve_linear_system():
>>>        error return status=1 from umfpack_numeric() routine
>>>
>>> is that an indication that umfpack is not installed correctly (i was never prompted to install it manually and the compilation of the Einstein toolkit [Maxwell release] went on smoothly without any errors), or rather that something is wrong trying to find the horizon? (there should be an horizon, because the lapse goes to 0 fairly quickly, after which the simulation eventually crashes)
>>
>> Hi Vassili,
>>
>> this error usually comes up when the arguments to umfpack_numeric() are not numbers (as would happen, for instance, if the metric had become singular). Could you check that your 3+1 variables are finite? Thorn NaNChecker could help you do that.
>
> If this turns out to be the problem, we should probably check for this in AHFinderDirect and give an error message.  Something like "The metric has become singular at [x,y,z]; unable to compute horizon and aborting the run".

Nah: "unable to compute horizon; continuing the run".

-erik

-- 
Erik Schnetter <schnetter at cct.lsu.edu>
http://www.perimeterinstitute.ca/personal/eschnetter/