On Wed, Feb 3, 2021 at 1:03 PM Sepideh Kavousi <[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]> > *Sent:* Wednesday, February 3, 2021 11:46 AM > *To:* Sepideh Kavousi <[email protected]>; [email protected] < > [email protected]> > *Subject:* Re: [petsc-users] SNES-norm is zero all the time > > Sepideh Kavousi <[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/ <http://www.cse.buffalo.edu/~knepley/>
