Thanks a lot.
> On 19-May-2018, at 9:16 PM, Smith, Barry F. <[email protected]> wrote:
>
> Praveen,
>
> Ahh, we didn't have support for passing PETSC_NULL_MAT from Fortran for
> this routine. I have added it in the branch
> barry/fix-null-matrix-set-jacobian/maint which after testing will go into
> the maint branch.
>
> Could you please try this branch and let us know if it resolves the problem
> (or a new problem pops up)?
>
> Barry
>
> Unfortunately handling null objects from Fortran requires us to manually
> tweak the Fortran interface functions and sometimes we forget or don't
> realize they need fixing until someone reports a problem.
I meanwhile passed a Mat object to TSSetRHSJacobian function. It seems that
with -snes_mf and PCSHELL, my RHSJacobian is never invoked. Is this the correct
behaviour ?
In RHSJacobian, I am storing the current solution into my usercontext so that I
can use it in my shell preconditioner
subroutine RHSJacobian(ts, time, u, J, P, ctx, ierr)
call VecCopy(u, ctx%p%v_u, ierr); CHKERRQ(ierr)
end
However, since my RHSJacobian is never invoked, I dont have access to the
current solution needed in my ApplyPC. How can I access the current solution in
my ApplyPC function ?
Another issue I am facing is this. I attach my user context to the PC
call TSGetSNES(ts, snes, ierr); CHKERRQ(ierr)
call SNESGetKSP(snes, ksp, ierr); CHKERRQ(ierr)
call KSPGetPC(ksp, pc, ierr); CHKERRQ(ierr)
call PCSetType(pc, PCSHELL, ierr); CHKERRQ(ierr)
call PCShellSetContext(pc, ctx, ierr); CHKERRQ(ierr)
call PCShellSetApply(pc, ApplyPC, ierr); CHKERRQ(ierr)
Inside my ApplyPC, I access ctx using
subroutine ApplyPC(pc, x, y, ierr)
use petscpc
use mtsdata
implicit none
PC :: pc
Vec :: x, y
PetscErrorCode :: ierr
! Local variables
type(tsdata) :: ctx
call PCShellGetContext(pc, ctx, ierr); CHKERRQ(ierr)
end
But the ctx I get from above is not correct, since it does not have the data I
stored in my original ctx.
I am rather clueless at this stage.
Thanks for your help.
Best regards
praveen
