Hi Max, Is your field solver not converging or the material point solver ;)?
Best regards, Luv > On 30 Jun 2017, at 10:45, Maximilian Hartig <imilian.har...@gmail.com> wrote: > > Hello, > > I’m trying to implement plasticity and have problems getting the Petsc SNES > to converge. To check if my residual formulation is correct I tried running > with -snes_fd for an easy example as the Petsc FAQ suggest. I cannot seem to > get the solver to converge at any cost. > I already tried to impose bounds on the solution and moved to vinewtonrsls as > a nonlinear solver. I checked and rechecked my residuals but I do not find an > error there. I now have the suspicion that the -snes_fd option is not made > for handling residuals who’s first derivatives are not continuous (e.g. have > an “if” condition in them for the plasticity/ flow-condition). Can you > confirm my suspicion? And is there another way to test my residual > formulation separate from my hand-coded jacobian? > > > Thanks, > Max
