<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">Thank you Barry and Emil.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">It works, but it takes twice as many steps than before.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">Was it wrong before? Should I have been using this option all along?</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">I am solving the Navier-Stokes equations, full implicit and non-linear.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">I also noticed two things:</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">In the 3.6.0 output, ts_monitor skips timestep #1.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">If I use the equation type in 3.5.4, I get segmentation fault.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">I attached the outputs.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Jun 18, 2015 at 1:24 PM, Emil Constantinescu <span dir="ltr"><<a href="mailto:emconsta@mcs.anl.gov" target="_blank">emconsta@mcs.anl.gov</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">No, I'm not sure if it should. It belongs to the same category as "problem_type" == TS_LINEAR / == TS_NONLINEAR.<br>
<br>
Emil<br>
<br>
<br>
On 6/18/15 11:15 AM, Abhyankar, Shrirang G. wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Can the DAE equation type be supplied via a run-time option?<br>
<br>
Shri<br>
<br>
-----Original Message-----<br>
From: barry smith <<a href="mailto:bsmith@mcs.anl.gov" target="_blank">bsmith@mcs.anl.gov</a>><br>
Date: Thursday, June 18, 2015 at 11:08 AM<br>
To: Italo Tasso <<a href="mailto:italo@tasso.com.br" target="_blank">italo@tasso.com.br</a>>, "Constantinescu, Emil M."<br>
<<a href="mailto:emconsta@mcs.anl.gov" target="_blank">emconsta@mcs.anl.gov</a>><br>
Cc: "<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>" <<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>><br>
Subject: Re: [petsc-users] arkimex rejecting all dt in petsc 3.6.0<br>
<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<br>
Here is the response from Emil who made the changes to the code<br>
<br>
If you are solving a DAE then in the new version, we introduced a new<br>
flag that distinguishes between ODEs and DAEs leading to different<br>
semantics. For DAEs this is needed b/c it may not have consistent initial<br>
conditions.<br>
<br>
If solving DAEs, the user has to set the EquationType appropriately:<br>
e.g.,<br>
ierr = TSSetEquationType(ts,TS_EQ_DAE_IMPLICIT_INDEX1);CHKERRQ(ierr);<br>
<br>
This is documented in the doc, but I didn't add it to the changelog (Jed<br>
pointed it out to me).<br>
<br>
Currently it only affects -ts_type arkimex. I'll work with Satish to add<br>
it to the changelog.<br>
<br>
*If that's not the case:* let me know and we can dig deeper.<br>
<br>
Emil<br>
<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
On Jun 18, 2015, at 5:48 AM, Italo Tasso <<a href="mailto:italo@tasso.com.br" target="_blank">italo@tasso.com.br</a>> wrote:<br>
<br>
I just upgraded to 3.6.0 and my code stopped working. All dt are<br>
rejected. I used the same configure line, same code, same everything.<br>
<br>
With 3.5.4 I get:<br>
<br>
0 TS dt 1e-06 time 0<br>
0 SNES Function norm 2.549981005316e+05<br>
1 SNES Function norm 6.107056905987e-03<br>
2 SNES Function norm 1.483881932064e-10<br>
3 SNES Function norm 9.122873794272e-11<br>
Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 3<br>
0 SNES Function norm 7.790429171165e+04<br>
1 SNES Function norm 7.289068747803e-04<br>
2 SNES Function norm 8.227639633330e-11<br>
Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2<br>
0 SNES Function norm 1.154356516184e+05<br>
1 SNES Function norm 2.309925413255e-03<br>
2 SNES Function norm 6.382141981406e-11<br>
Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2<br>
TSAdapt 'basic': step 0 accepted t=0 + 1.000e-06<br>
wlte=0.000654 family='arkimex' scheme=0:'3' dt=1.000e-05<br>
<br>
With 3.6.0 I get:<br>
<br>
0 TS dt 1e-06 time 0<br>
0 SNES Function norm 2.549981005316e+05<br>
1 SNES Function norm 6.107056925316e-03<br>
2 SNES Function norm 1.519319591792e-10<br>
3 SNES Function norm 9.070104116945e-11<br>
Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 3<br>
0 SNES Function norm 7.790429171165e+04<br>
1 SNES Function norm 6.942541792651e-04<br>
2 SNES Function norm 8.458781909516e-11<br>
Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2<br>
0 SNES Function norm 1.154356516184e+05<br>
1 SNES Function norm 2.287202942961e-03<br>
2 SNES Function norm 6.585201377573e-11<br>
Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 2<br>
TSAdapt 'basic': step 0 rejected t=0 + 1.000e-06 wlte=<br>
324 family='arkimex' scheme=0:'3' dt=1.311e-07<br>
<br>
Any ideas? I attached the full output.<br>
<br>
Options I use:<br>
<br>
-ts_view -ts_type arkimex -ts_arkimex_fully_implicit -ts_adapt_monitor<br>
-ts_monitor -snes_monitor -snes_converged_reason -ksp_type preonly<br>
-pc_type lu -pc_factor_mat_solver_package mumps -snes_rtol 0 -snes_atol<br>
1e-10 -snes_stol 0<br>
<br>
<petsc354.txt><petsc360.txt><br>
</blockquote>
<br>
</blockquote>
<br>
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</blockquote></div><br></div></div>