Oh my god, it was a bad one. Thanks for helping. Sepideh ________________________________ From: Matthew Knepley <[email protected]> Sent: Wednesday, February 3, 2021 12:14 PM To: Sepideh Kavousi <[email protected]> Cc: Jed Brown <[email protected]>; [email protected] <[email protected]> Subject: Re: [petsc-users] SNES-norm is zero all the time
On Wed, Feb 3, 2021 at 1:03 PM Sepideh Kavousi <[email protected]<mailto:[email protected]>> wrote: I only have one field "names vx" and this variable change in both x and y directions. I have also chosen dof in DMDACreate2d to "1". I am not sure why I should have aF[i][j].vx. "i" defines the grids in x direction and "j" is in y-directions. In all my previous codes I define" aF[j][i].vx" and not "aF[i][j].vx", and it was working properly. To me, it looks like you have "jj" Matt Best, Sepideh ________________________________ From: Jed Brown <[email protected]<mailto:[email protected]>> Sent: Wednesday, February 3, 2021 11:46 AM To: Sepideh Kavousi <[email protected]<mailto:[email protected]>>; [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> Subject: Re: [petsc-users] SNES-norm is zero all the time Sepideh Kavousi <[email protected]<mailto:[email protected]>> writes: > I am not running an specific example. Attached is my code. and when I wun > with > ./step5.out -snes_monitor -snes_fd_color -ts_monitor -snes_converged_reason > -pc_type lu > > it seems it does not solve anything because the output is like: > > 0 SNES Function norm 0.000000000000e+00 > Nonlinear solve converged due to CONVERGED_FNORM_ABS iterations 0 > 1 TS dt 0.005 time 0.005 Check your FormFunction for why af[][] is zero. I see aF[j][j].vx but you'll need to set at all the grid points, i.e., aF[j][i].vx and aF[j][i].vy. -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/<https://nam04.safelinks.protection.outlook.com/?url=http:%2F%2Fwww.cse.buffalo.edu%2F~knepley%2F&data=04%7C01%7Cskavou1%40lsu.edu%7C9aa72ef56f15478b6e0e08d8c86f8841%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C0%7C637479728645895019%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=CcQ%2BasyQnfdLmGdPbqBospHzu6DPt6sXte4x%2BHp8e%2F8%3D&reserved=0>
