[petsc-users] -snes_mf and -snes_fd

[Barry Smith]

> On May 5, 2016, at 11:03 PM, Jed Brown <jed at jedbrown.org> wrote:
> 
> Matthew Knepley <knepley at gmail.com> writes:
>>> without -snes_mf AT ALL but with -snes_fd 0 I get RHS called 3 times [1]
>>> 
>> 
>> I need to see the output of -snes_view for these cases. Its possible that we
>> have a bug related to the argument.
> 
> This case looks correct to me.  It's the same as passing no options, so
> the analytic Jacobian gets used.  That said, our options scheme is lame
> to use separate options when only one can possibly be used.  We should
> have -snes_jacobian <analytic,mf,mf_operator,fd,fd_color> or similar.

   Perhaps it should have two parts; one for the mat and one for the pmat. So -snes_jacobian X[:Y] where X can be analytic, mf,fd,fd_color and Y can be analytic,fd,fd_color,none

   Make it an issue.

Barry