[petsc-users] arkimex rejecting all dt in petsc 3.6.0

[Abhyankar, Shrirang G.]

Can the DAE equation type be supplied via a run-time option?

Shri

-----Original Message-----
From: barry smith <bsmith at mcs.anl.gov>
Date: Thursday, June 18, 2015 at 11:08 AM
To: Italo Tasso <italo at tasso.com.br>, "Constantinescu, Emil M."
<emconsta at mcs.anl.gov>
Cc: "petsc-users at mcs.anl.gov" <petsc-users at mcs.anl.gov>
Subject: Re: [petsc-users] arkimex rejecting all dt in petsc 3.6.0

>
>  Here is the response from Emil who made the changes to the code
>
>If you are solving a DAE then in the new version, we introduced a new
>flag that distinguishes between ODEs and DAEs leading to different
>semantics. For DAEs this is needed b/c it may not have consistent initial
>conditions.
>
>If solving DAEs, the user has to set the EquationType appropriately:
>e.g.,
>ierr = TSSetEquationType(ts,TS_EQ_DAE_IMPLICIT_INDEX1);CHKERRQ(ierr);
>
>This is documented in the doc, but I didn't add it to the changelog (Jed
>pointed it out to me).
>
>Currently it only affects -ts_type arkimex. I'll work with Satish to add
>it to the changelog.
>
>*If that's not the case:* let me know and we can dig deeper.
>
>Emil
>
>> On Jun 18, 2015, at 5:48 AM, Italo Tasso <italo at tasso.com.br> wrote:
>> 
>> I just upgraded to 3.6.0 and my code stopped working. All dt are
>>rejected. I used the same configure line, same code, same everything.
>> 
>> With 3.5.4 I get:
>> 
>> 0 TS dt 1e-06 time 0
>>     0 SNES Function norm 2.549981005316e+05
>>     1 SNES Function norm 6.107056905987e-03
>>     2 SNES Function norm 1.483881932064e-10
>>     3 SNES Function norm 9.122873794272e-11
>>   Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 3
>>     0 SNES Function norm 7.790429171165e+04
>>     1 SNES Function norm 7.289068747803e-04
>>     2 SNES Function norm 8.227639633330e-11
>>   Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2
>>     0 SNES Function norm 1.154356516184e+05
>>     1 SNES Function norm 2.309925413255e-03
>>     2 SNES Function norm 6.382141981406e-11
>>   Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2
>>       TSAdapt 'basic': step   0 accepted t=0          + 1.000e-06
>>wlte=0.000654 family='arkimex' scheme=0:'3' dt=1.000e-05
>> 
>> With 3.6.0 I get:
>> 
>> 0 TS dt 1e-06 time 0
>>     0 SNES Function norm 2.549981005316e+05
>>     1 SNES Function norm 6.107056925316e-03
>>     2 SNES Function norm 1.519319591792e-10
>>     3 SNES Function norm 9.070104116945e-11
>>   Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 3
>>     0 SNES Function norm 7.790429171165e+04
>>     1 SNES Function norm 6.942541792651e-04
>>     2 SNES Function norm 8.458781909516e-11
>>   Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2
>>     0 SNES Function norm 1.154356516184e+05
>>     1 SNES Function norm 2.287202942961e-03
>>     2 SNES Function norm 6.585201377573e-11
>>   Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2
>>       TSAdapt 'basic': step   0 rejected t=0          + 1.000e-06 wlte=
>> 324 family='arkimex' scheme=0:'3' dt=1.311e-07
>> 
>> Any ideas? I attached the full output.
>> 
>> Options I use:
>> 
>> -ts_view -ts_type arkimex -ts_arkimex_fully_implicit -ts_adapt_monitor
>>-ts_monitor -snes_monitor -snes_converged_reason -ksp_type preonly
>>-pc_type lu -pc_factor_mat_solver_package mumps -snes_rtol 0 -snes_atol
>>1e-10 -snes_stol 0
>> 
>> <petsc354.txt><petsc360.txt>
>