<div dir="ltr"><div dir="ltr">On Wed, Feb 3, 2021 at 12:39 PM Sepideh Kavousi <<a href="mailto:skavou1@lsu.edu">skavou1@lsu.edu</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
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I am not running an specific example. Attached is my code. and when I wun with </div>
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./step5.out -snes_monitor -snes_fd_color -ts_monitor -snes_converged_reason -pc_type lu</div></div></blockquote><div><br></div><div>Did you mean [i][j] here?</div><div><br></div><div> aF[j][j].vx=((vx_x+vx_y)-1*aYdot[j][i].vx*(1));<br><br></div><div> Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">
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it seems it does not solve anything because the output is like:</div>
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0 SNES Function norm 0.000000000000e+00
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>1 TS dt 0.005 time 0.005</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>2 TS dt 0.005 time 0.01</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>3 TS dt 0.005 time 0.015</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>4 TS dt 0.005 time 0.02</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>5 TS dt 0.005 time 0.025</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>6 TS dt 0.005 time 0.03</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>7 TS dt 0.005 time 0.035</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>8 TS dt 0.005 time 0.04</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>9 TS dt 0.005 time 0.045</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>10 TS dt 0.005 time 0.05</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
<div>11 TS dt 0.005 time 0.055</div>
<div>copy!</div>
<div> 0 SNES Function norm 0.000000000000e+00 </div>
<div> Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0</div>
.......</div>
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<div id="gmail-m_-2874880173742128337divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Jed Brown <<a href="mailto:jed@jedbrown.org" target="_blank">jed@jedbrown.org</a>><br>
<b>Sent:</b> Wednesday, February 3, 2021 11:19 AM<br>
<b>To:</b> Sepideh Kavousi <<a href="mailto:skavou1@lsu.edu" target="_blank">skavou1@lsu.edu</a>>; <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>
<b>Subject:</b> Re: [petsc-users] SNES-norm is zero all the time</font>
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<div>Sepideh Kavousi <<a href="mailto:skavou1@lsu.edu" target="_blank">skavou1@lsu.edu</a>> writes:<br>
<br>
> Hello,<br>
> I have a very stupid problem that I am really ashamed of asking but it has been with me for days and I do not know what to do. I want to solve the Javier stokes equation with finite difference method.
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Could you run with -snes_monitor -snes_converged_reason -pc_type lu?<br>
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> When I wanted to run the code, the snes norm value does not change and i get an error for timestep convergence. I thought I might do something wrong so, I tried to simplify the equation I want to solve to an easy form, given as: u_t=u_x +u_y Where _t is the
time derivative and _x and _y are the derivative in x and y direction. When I want to solve this problem, it still does not do anything at all and the snes function norm is zero all the time. I know I am missing something but does anyone have any idea what
should I check in my code. The answers does not change with time. Best, Sepideh<br>
><br>
><br>
> Get Outlook for iOS<<a href="https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Faka.ms%2Fo0ukef&data=04%7C01%7Cskavou1%40lsu.edu%7C07c0cc86cc4d4100e28a08d8c8680396%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C0%7C637479696353544458%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=A7xZE31UylQvnMnTFIcZj60GToFHW%2FsumLS9kIISEWo%3D&reserved=0" target="_blank">https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Faka.ms%2Fo0ukef&data=04%7C01%7Cskavou1%40lsu.edu%7C07c0cc86cc4d4100e28a08d8c8680396%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C0%7C637479696353544458%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=A7xZE31UylQvnMnTFIcZj60GToFHW%2FsumLS9kIISEWo%3D&reserved=0</a>><br>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener</div><div><br></div><div><a href="http://www.cse.buffalo.edu/~knepley/" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>