Change option for NewtonSolver when solver doesn't converge

[Daniel.Baker]

Wouldn’t this link be the easiest way?

Set krylov linear solver paramters in newton solver

Looks like old DOLFIN intercepts a PETSc error and then throws its own should the KSP iterations exceed their limit. Quick solution is to handle it with python: try: custom_solver.solve(problem, u.vector()) except Exception as e: # Handle the error within your time stepping algorithm gracefully... Consider using a PETScSNESSolver and its underlying SNES and KSP objects to get more information about the lack of convergence. Also consider foregoing DOLFIN’s implementations of Newton and …