Do you start with initial conditions of 0 <= u_i <= 1 ?
Run with -snes_monitor -snes_converged_reason -ksp_monitor_true_residual
-info -snes_linesearch_monitor and send all the output
Barry
> On Sep 11, 2018, at 11:33 PM, Josh L <[email protected]> wrote:
>
> Hi,
>
> I am using SNES to solve an nonlinear equation f(u), and I know all the u_i
> should be 0 and 1.
>
> First, I use SNES without constraint, and it converges.
>
> But, If I set
> SNESSetType(snes,SNESVINEWTONRSLS,ierr)
> SNESVISetVariableBounds(snes,xl,xu,ierr)
>
> where xl and xu is vector, and xl_i=0 and xu_i=1
>
> then SNES fails to converge, because linesearch fails(snes reason = -6), and
> the norm of residual is not reducing(the norm of incremental solution is
> reducing)
>
> The reason to add constraint is that I want to implement some irreversibility.
>
>
> Thanks,
> Josh
>
