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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple style='word-wrap: break-word;-webkit-nbsp-mode: space;line-break:after-white-space'><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Sure after reaching a steady state it looks like this:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 3.767377637168e-03 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 2.529971638368e-05 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 2 SNES Function norm 4.433873358247e-09 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 3 SNES Function norm 4.535675922104e-11 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 9.898938706929e-04 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 1.322473621975e-05 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 2 SNES Function norm 1.672724799379e-09 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 3 SNES Function norm 1.338501638801e-11 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 1.624500221071e-03 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 2.448515345247e-05 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 2 SNES Function norm 6.225549426481e-09 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 3 SNES Function norm 1.062516222150e-10 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 4 SNES Function norm 6.493758120241e-13 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 1.106311709708e-03 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 2.475673243430e-05 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 2 SNES Function norm 9.969586735411e-09 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 3 SNES Function norm 2.479591395229e-10 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 4 SNES Function norm 1.542689576708e-12 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 6.070943996748e-04 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 1.648134285171e-05 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 2 SNES Function norm 8.461078655420e-09 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 3 SNES Function norm 2.480863447790e-10 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 4 SNES Function norm 1.513977618851e-12 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> TSAdapt basic arkimex 0:4 step 15 accepted t=5.67201 + 4.328e+00 dt=4.687e+00 wlte$<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>0.477 wltea= -1 wlter= -1 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>If I set the next target time (in tssolve) to be tlast+1e-3 it looks like this:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 4.734802409365e-03 <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 6.173939866359e-13<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 5.633294284900e-04<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 3.575533754564e-13<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 9.651618110271e-04<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 6.863177319359e-13<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 7.706102281617e-04<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 8.490865565002e-13<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 0 SNES Function norm 5.028108294534e-04<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> 1 SNES Function norm 6.905750968862e-13<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'> TSAdapt basic arkimex 0:4 step 16 accepted t=10 + 1.000e-03 dt=2.612e-03 wlte$<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>0.0141 wltea= -1 wlter= -1<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>The SNES solver has a atoll of 1e-10, setting the atoll to lower values does not change the result.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Thank you,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Moritz<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Von:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Zhang, Hong <hongzhang@anl.gov> <br><b>Gesendet:</b> Donnerstag, 13. Dezember 2018 16:42<br><b>An:</b> Huck, Moritz <Moritz.Huck@isea.rwth-aachen.de><br><b>Cc:</b> petsc-users@mcs.anl.gov<br><b>Betreff:</b> Re: [petsc-users] Solution "jumps" after setting timestep<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Can you please add command line options -ts_monitor -snes_monitor and show us the outputs? <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks,<o:p></o:p></p></div><div><p class=MsoNormal>Hong (Mr.)<o:p></o:p></p></div><div><p class=MsoNormal><br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>On Nov 4, 2018, at 6:19 AM, Moritz.Huck--- via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>Hi,<span class=apple-tab-span><o:p></o:p></span></span></p><p class=MsoNormal><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'><br>I using the basic adaptor.<br>If I let the adaptor handle everything it does not oscillates.<br>I don’t mean setting the timestep at the start (which does not produces the<br>problem),<br>I need to set during runtime between two steps.<br><br>Best Regards,<br><br>Moritz<br><br>-----Ursprüngliche Nachricht-----<br>Von: Constantinescu, Emil M. <</span><a href="mailto:emconsta@anl.gov"><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>emconsta@anl.gov</span></a><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>><span class=apple-converted-space> </span><br>Gesendet: Samstag, 3. November 2018 15:43<br>An: Huck, Moritz <</span><a href="mailto:Moritz.Huck@isea.rwth-aachen.de"><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>Moritz.Huck@isea.rwth-aachen.de</span></a><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>>;<span class=apple-converted-space> </span></span><a href="mailto:petsc-users@mcs.anl.gov"><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>petsc-users@mcs.anl.gov</span></a><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'><br>Betreff: Re: [petsc-users] Solution "jumps" after setting timestep<br><br>On 11/3/18 4:56 AM, Moritz.Huck--- via petsc-users wrote:<br style='caret-color: rgb(0, 0, 0);font-variant-caps: normal;text-align:start;-webkit-text-stroke-width: 0px;word-spacing:0px'><br></span><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>Hi,<br><br>I am using the IMEX Runge Kutta to solve an implicit DAE (G=0).<br><br>When I manually set the time step (TSSetTimestep) my solution jumps.<o:p></o:p></span></p></blockquote><p class=MsoNormal><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'><br>When you don't set the time step, does it still oscillates? If not, can you<br>check if it oscillates when reducing the fixed initial time step?<span class=apple-converted-space> </span><br>Did you turn the adaptivity off (-ts_adapt_type none)?<br><br>Emil<br><br><br style='caret-color: rgb(0, 0, 0);font-variant-caps: normal;text-align:start;-webkit-text-stroke-width: 0px;word-spacing:0px'><br></span><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><span style='font-size:10.5pt;font-family:"Verdana",sans-serif'>If I go from a steady state to the same state, it oscillates a few<span class=apple-converted-space> </span><br>time and comes back to the steady solution.<br><br>Can this be prevented?<br><br>Thank you,<br><br>Moritz<o:p></o:p></span></p></blockquote></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></body></html>