SNES Problem
Nils Erik Svangård
nilserik at gmail.com
Tue Mar 14 14:02:27 CST 2006
> > Yes, there is a difference between the old 3-stage RK-solver and the
> > SNESsolver using RK. In the old a timestep was calculatade for each
> ^^^^^^^^^^^^^^^
> Are you using PETSc's explicit RK? If so that does not use SNES.
>
Sorry, I meant TS.
> > cell based on a stability criteria and if chosen it could run in
> > time-accurate mode eg. the timestep is the same for each cell, in SNES
> ^^^^^^^^^
> Do you mean for backward Euler for the explicit RK? Or both?
Sorry again, using TS I use the same size of the timestep on every
cell (both when trying use back-euler and RK).
In my old 3-stage RK I can use both variable timestep and
time-accurate timestep.
In my seperate back-euler implementation using SNES I use the same
timestep on every cell.
>
> > I use a timestep that is the same for all cells and
> > changes only if it returns non-physical answers or the solution diverges.
>
> I think you need to put the "proper" computation of the time-step
> based on the stability criteria that you have in the "old" code.
> Unfortunately this is currently hardwired in src/ts/impls/explicit/rk/rk.c
> (search for "Computing next stepsize"). I think you need to use the minimum
> of the timestep computed here and what is needed for the "stability criteria".
>
Hmm.. Ok so I could use my back-euler SNES implementation with my old
timestep calculation function (using time-accurate timestep)? And it
might work better.
Thanks
/nisse
> >
> > Another interesting observation is that when using back euler at the
> > moment when it bugs out petsc has assigned neigboring cells pressure
> > values that differs about 1 ATM, which is a very non physical value,
>
> Likely some stability problem.
>
> Barry
>
> > but I have no clue as to why petsc want such a value in thesolution.
> >
> > /nisse
> >
> > On 3/3/06, Barry Smith <bsmith at mcs.anl.gov> wrote:
> >>
> >> There must be a difference between the two RKs. The initial
> >> timestep it uses, or algorithm for changing time step or slight
> >> difference in algorithms?
> >>
> >> Barry
> >>
> >> On Fri, 3 Mar 2006, Nils Erik Svangård wrote:
> >>
> >>> A interesting thing is when I change TS_BEULER to TS_RUNGE_KUTTA the
> >>> solver exits fast due to the non physical values. My original solver
> >>> is a 3-step Runge-Kutta which works flawlessly.
> >>>
> >>> The error when running RK:
> >>>
> >>> ./ImplicitG3D on a linux-gnu named sethnx004.vac.com by yy26539 Fri
> >>> Mar 3 10:31:27 2006
> >>> Libraries linked from /home/yy26539/work/NISSE/petsc-2.3.0/lib/linux-gnu
> >>> Configure run at Thu Oct 13 08:23:56 2005
> >>> Configure options --with-cc=gcc --with-fc="f77 -N109"
> >>> --download-mpich=1 --download-mpich-pm=gforker
> >>> --download-f-blas-lapack=1 --with-shared=0
> >>> -----------------------------------------------------------------------
> >>> [0]PETSC ERROR: Caught signal number 8 FPE: Floating Point
> >>> Exception,probably divide by zero
> >>> [0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger
> >>> [0]PETSC ERROR: likely location of problem given in stack below
> >>> [0]PETSC ERROR: --------------- Stack Frames ---------------
> >>> [0]PETSC ERROR: Note: The EXACT line numbers in the stack are not available,
> >>> [0]PETSC ERROR: INSTEAD the line number of the start of the function
> >>> [0]PETSC ERROR: is given.
> >>> [0]PETSC ERROR: [0] TS user right-hand-side function line 0 unknownunknown
> >>> [0]PETSC ERROR: [0] TSComputeRHSFunction line 282 src/ts/interface/ts.c
> >>> [0]PETSC ERROR: [0] TSRkqs line 256 src/ts/impls/explicit/rk/rk.c
> >>> [0]PETSC ERROR: [0] TSStep_Rk line 322 src/ts/impls/explicit/rk/rk.c
> >>> [0]PETSC ERROR: [0] TSStep line 1520 src/ts/interface/ts.c
> >>> [0]PETSC ERROR: --------------------------------------------
> >>> [0]PETSC ERROR: User provided function() line 0 in unknown directory
> >>> unknown file
> >>> [0]PETSC ERROR: Signal received!
> >>> [0]PETSC ERROR: !
> >>> aborting job:
> >>> application called MPI_Abort(MPI_COMM_WORLD, 59) - process 0
> >>>
> >>> On 3/3/06, Nils Erik Svangård <nilserik at gmail.com> wrote:
> >>>> Hello again,
> >>>>
> >>>>> Is it just not compiling because PETSC_ERR_ARG_DOMAIN is not
> >>>>> defined? Or does it still not work even when you have put the number in?
> >>>>> What is the error? Or did you get it all working with SNES?
> >>>>>
> >>>>
> >>>>
> >>>> It is not compiling because PETSC_ERR_ARG_DOMAIN is not defined:
> >>>>
> >>>> error on line 585 of SNESG3D2.F: data type is undefined for variable
> >>>> PETSC_ERR_ARG_DOMAIN
> >>>>
> >>>> I tried putting a number in, then it compiles but complains while
> >>>> linking that the Push() and Pop() functions is not defined. I made a
> >>>> workaround by adding a variable in a common block and setting it
> >>>> before returning from a non physical value in the FormFunction. Now I
> >>>> can compile and when there is a non-physical value it returns and
> >>>> resumes with a smaller timestep.
> >>>> SNES still give non physical values which are hard to add checks for
> >>>> in the program (e.g sqrt(RO(L)-RO(L+1))).
> >>>>
> >>>> Did I understand correctly that SNES does a linesearch and probably
> >>>> goes for a solution which isnt the one I looking for? Does SNES use
> >>>> the linesearch algorithm when I use -snes_mf (which I use)?
> >>>>
> >>>>> It may work automatically with TS; you would just set TS with a
> >>>>> smaller timestep and call TSSolve again?
> >>>>>
> >>>>
> >>>> OK, I'll add a check and put TSSolve in a while loop.
> >>>>
> >>>> My SNESSolve loop looks like this right now:
> >>>> call VecCreateSeq(PETSC_COMM_SELF,N,x,ierr)
> >>>> call VecDuplicate(x,r,ierr)
> >>>> call VecDuplicate(x,xb,ierr)
> >>>> call SNESCreate(PETSC_COMM_SELF,snes,ierr)
> >>>> call SNESSetFunction(snes,r,FormFunction,PETSC_NULL_OBJECT,ierr)
> >>>> call SNESSetFromOptions(snes,ierr)
> >>>> call FormInitialGuess(x,ierr)
> >>>> call VecCopy(x,xb,ierr)
> >>>> write(6,*)zero,dt,tmax,i1000
> >>>> step=0
> >>>> timestep=dt
> >>>> bang=0
> >>>> C While loop
> >>>> 10 if (step .le. 100) then
> >>>> C call PetscExceptionPush(87,ierr)
> >>>> C call PetscExceptionPush(PETSC_ERR_ARG_DOMAIN,ierr)
> >>>> call SNESSolve(snes,PETSC_NULL_OBJECT,x,ierr)
> >>>> ierr=bang
> >>>> C call PetscExceptionPop(87,ierr2)
> >>>> IF ( ierr .EQ. 87) THEN
> >>>> timestep=timestep/2
> >>>> call VecCopy(xb,x,ierr)
> >>>> write(6,*) "No physical solution, trying",
> >>>> . " with smaller timestep: ",timestep
> >>>> bang=0
> >>>> ELSE
> >>>> call SNESGetConvergedReason(snes,reason,ierr)
> >>>> IF ( reason .LT. 0 ) THEN
> >>>> timestep=timestep/2
> >>>> call VecCopy(xb,x,ierr)
> >>>> write(6,*)"Solution diverged, trying with",
> >>>> . " smaller timestep: ",timestep
> >>>> ELSE
> >>>> timestep=dt
> >>>> step=step+1
> >>>> call VecCopy(x,xb,ierr)
> >>>> write(6,*) "Solve success, going for step: ",step
> >>>> write(6,*) "Reason: ",reason," ierr: ",ierr
> >>>> reason=0
> >>>> ierr=0
> >>>> ENDIF
> >>>> ENDIF
> >>>> goto 10
> >>>> endif
> >>>> C End While loop
> >>>>
> >>>> And the check in the FormFunction:
> >>>>
> >>>> if (ET(L) .LT. 0) then
> >>>> ierr = 87
> >>>> bang = 87
> >>>> C SETERRQ(87,"Non physical value!",ierr)
> >>>> return
> >>>> elseif ( RO(L) .LT. 0 ) then
> >>>> ierr = 87
> >>>> bang = 87
> >>>> return
> >>>> endif
> >>>>
> >>>>
> >>>> /nisse
> >>>>
> >>>>
> >>>>
> >>>>> Barry
> >>>>>
> >>>>> I'm adding a petscerror.h for Fortran that includes these values
> >>>>> Sorry I forgot we hadn't given them for Fortran.
> >>>>>
> >>>>> On Thu, 2 Mar 2006, Nils Erik Svangård wrote:
> >>>>>
> >>>>>> Hi again,
> >>>>>> I realised that my implementation was a bit flawed so I have rewritten
> >>>>>> it again, the push and pop() functions dont seem to work, and they are
> >>>>>> keeping me from compiling the program, this is the main timestep loop:
> >>>>>>
> >>>>>> call VecCreateSeq(PETSC_COMM_SELF,N,x,ierr)
> >>>>>> call VecDuplicate(x,r,ierr)
> >>>>>> call VecDuplicate(x,xb,ierr)
> >>>>>> call SNESCreate(PETSC_COMM_SELF,snes,ierr)
> >>>>>> call SNESSetFunction(snes,r,FormFunction,PETSC_NULL_OBJECT,ierr)
> >>>>>> call SNESSetFromOptions(snes,ierr)
> >>>>>> call FormInitialGuess(x,ierr)
> >>>>>> call VecCopy(x,xb,ierr)
> >>>>>> write(6,*)zero,dt,tmax,i1000
> >>>>>> step=0
> >>>>>> timestep=dt
> >>>>>> C While loop
> >>>>>> 10 if (step .le. 100) then
> >>>>>> call PetscExceptionPush(87,ierr)
> >>>>>> call SNESSolve(snes,PETSC_NULL_OBJECT,x,ierr)
> >>>>>> call PetscExceptionPop(87,ierr2)
> >>>>>>
> >>>>>> call SNESGetConvergedReason(snes,reason,ierr)
> >>>>>> IF ( reason .LT. 0 ) THEN
> >>>>>> timestep=timestep/2
> >>>>>> VecCopy(xb,x,ierr)
> >>>>>> write(6,*)"Solution diverged, trying with",
> >>>>>> . " smaller timestep: ",timestep
> >>>>>> ELSE
> >>>>>> IF ( ierr .EQ. 87) THEN
> >>>>>> timestep=timestep/2
> >>>>>> VecCopy(xb,x,ierr)
> >>>>>> write(6,*) "No physical solution, trying",
> >>>>>> . " with smaller timestep: ",timestep
> >>>>>> ELSE
> >>>>>> timestep=dt
> >>>>>> step=step+1
> >>>>>> VecCopy(x,xb,ierr)
> >>>>>> write(6,*) "Solve success, going for step: ",step
> >>>>>> ENDIF
> >>>>>> ENDIF
> >>>>>> goto 10
> >>>>>> endif
> >>>>>> C End While loop
> >>>>>>
> >>>>>> And in my Formfunction I have added the following check:
> >>>>>> if (ET(L) .LT. 0) then
> >>>>>> ierr = 87
> >>>>>> return
> >>>>>> endif
> >>>>>>
> >>>>>> PETSC_ERR_ARG_DOMAIN didnt work: error on line 6500 of SNESG3D2.F:
> >>>>>> data type is undefined for variable PETSC_ERR_ARG_DOMAIN
> >>>>>> Even thought I had petsc.h included.
> >>>>>>
> >>>>>> Can I do this check when I use TS also? I have the sameproblem with
> >>>>>> the values being negative when using TS.
> >>>>>>
> >>>>>>
> >>>>>> /nisse
> >>>>>>
> >>>>>>
> >>>>>> On 2/27/06, Barry Smith <bsmith at mcs.anl.gov> wrote:
> >>>>>>>
> >>>>>>> SNES works by computing p = -approxinv(J)*F(uold) and
> >>>>>>> then does a line search on unew = uold + lambda*p to get the
> >>>>>>> new u. First it uses a test value of 1 for lambda so it
> >>>>>>> tries to compute F(uold + p). It is possible that uold + p
> >>>>>>> has some "non-physical" values in it. There are two ways
> >>>>>>> you can try handling it:
> >>>>>>>
> >>>>>>> 1) Before doing the linesearch SNES calls a "precheck" function,
> >>>>>>> that can change the step if it decides there is a problem
> >>>>>>> with the step (like it is too long). You can provide your
> >>>>>>> own precheck function with SNESLineSearchSetPreCheck() it could,
> >>>>>>> for example, shrink the Newton direction to make it remain physical.
> >>>>>>>
> >>>>>>> or 2) when your form function detects an illegal value it calls
> >>>>>>> SETERRQ(PETSC_ERR_ARG_DOMAIN,"Nonphysical function input"); Note:
> >>>>>>> this is before it takes the square root of the negative number,
> >>>>>>> so check the number and call the error before calling SETERRQ().
> >>>>>>> (If using Fortran then simply set ierr = PETSC_ERR_ARG_DOMAIN and
> >>>>>>> then immediately return). Then replace your call to SNESSolve with
> >>>>>>> ierr = PetscExceptionTry1(SNESSolve(snes,b,x),PETSC_ERR_ARG_DOMAIN);
> >>>>>>> if (PetscExceptionCaught(ierr,PETSC_ERR_ARG_DOMAIN)) {
> >>>>>>> /* this means your function found a non-physical value so
> >>>>>>> cut your time-step and continue through the loop again. */
> >>>>>>> Put code to do this here.
> >>>>>>> }
> >>>>>>> If using fortran then do
> >>>>>>> call PetscExceptionPush(PETSC_ERR_ARG_DOMAIN,ierr)
> >>>>>>> call SNESSolve(snes,b,x,ierr)
> >>>>>>> call PetscExceptionPop(PETSC_ERR_ARG_DOMAIN,anotherierr)
> >>>>>>> if (ierr == PETSC_ERR_ARG_DOMAIN) then
> >>>>>>> non-physical value so cut the time-step and try again
> >>>>>>> else ! everything is normal so take the next time-step
> >>>>>>>
> >>>>>>> Barry
> >>>>>>>
> >>>>>>> The Fortran interface may be missing PetscExceptionPush() and Pop()
> >>>>>>> if so let us know and we'll provide the patch.
> >>>>>>>
> >>>>>>> On Mon, 27 Feb 2006, Nils Erik Svangård wrote:
> >>>>>>>
> >>>>>>>> Hi all,
> >>>>>>>>
> >>>>>>>> I have problems solving some CFD problems using SNES and my custom
> >>>>>>>> back-euler. I have 7 equations that I want to solve.
> >>>>>>>>
> >>>>>>>> First my FormFunction copies the values from the Vec that SNES uses to
> >>>>>>>> the variables that my code use:
> >>>>>>>>
> >>>>>>>> RO(L)=xx(1,L)
> >>>>>>>> RU(L)=xx(2,L)
> >>>>>>>> RV(L)=xx(3,L)
> >>>>>>>> RW(L)=xx(4,L)
> >>>>>>>> ET(L)=xx(5,L)
> >>>>>>>> RQ(L)= xx(6,L)
> >>>>>>>> REPS(L)=xx(7,L)
> >>>>>>>>
> >>>>>>>> Here I also print the values of ET(2) for debugging:
> >>>>>>>>
> >>>>>>>> write(6,*)"ET(2) = xx(5,2) : ",ET(2)," = ",xx(5,2)
> >>>>>>>>
> >>>>>>>> Then I get the fluxes by calling custom functions
> >>>>>>>>
> >>>>>>>> call AUXVR
> >>>>>>>> call VGRAD
> >>>>>>>> call FLUX
> >>>>>>>> call KESRC
> >>>>>>>>
> >>>>>>>> Then I perform back-euler save the new value to so that I can use it
> >>>>>>>> in the next iterationi (TSF(L) is Time step function, which is set by
> >>>>>>>> hand and is the same for all L):
> >>>>>>>>
> >>>>>>>> ff(1,L) = RO(L)-OLD(1,L)-TSF(L)*DRO(L)
> >>>>>>>> ff(2,L) = RU(L)-OLD(2,L)-TSF(L)*DRU(L)
> >>>>>>>> ff(3,L) = RV(L)-OLD(3,L)-TSF(L)*DRV(L)
> >>>>>>>> ff(4,L) = RW(L)-OLD(4,L)-TSF(L)*DRW(L)
> >>>>>>>> ff(5,L) = ET(L)-OLD(5,L)-TSF(L)*DET(L)
> >>>>>>>> ff(6,L) = RQ(L)-OLD(6,L)-TSF(L)*DRQ(L)
> >>>>>>>> ff(7,L) = REPS(L)-OLD(7,L)-TSF(L)*DREPS(L)
> >>>>>>>>
> >>>>>>>> And save the new value of RO-REPS to use in the next iteration of back-euler:
> >>>>>>>>
> >>>>>>>> OLD(1,L)=RO(L)
> >>>>>>>> OLD(2,L)=RU(L)
> >>>>>>>> OLD(3,L)=RV(L)
> >>>>>>>> OLD(4,L)=RW(L)
> >>>>>>>> OLD(5,L)=ET(L)
> >>>>>>>> OLD(6,L)=RQ(L)
> >>>>>>>> OLD(7,L)=REPS(L)
> >>>>>>>>
> >>>>>>>> Here I print the values of L=2 as above for debugging:
> >>>>>>>>
> >>>>>>>> write(6,*)ff(5,2)," = ",ET(2),"-",OLD(5,2),"-",TSF(2),"*",DET(2)
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> The program exit abnormaly after 33 runs of the FormFunction. The
> >>>>>>>> cause of this is that AUXVR tries to perform sqrt(ET(2)) when ET(2) is
> >>>>>>>> negative, ET is the total energy and should never be negative. It
> >>>>>>>> seems that all of a sudden the PETSc SNES solver decides to supply the
> >>>>>>>> FormFunction with a negative ET value. I need help understanding why
> >>>>>>>> and how to fix it (if it is fixable).
> >>>>>>>>
> >>>>>>>> Here is the output of:
> >>>>>>>> write(6,*)"ET(2) = xx(5,2) : ",ET(2)," = ",xx(5,2)
> >>>>>>>> Which is in the beginning of my FormFunction.
> >>>>>>>> And:
> >>>>>>>> write(6,*)ff(5,2)," = ",ET(2),"-",OLD(5,2),"-",TSF(2),"*",DET(2)
> >>>>>>>> Which is in the end of my Formfunction.
> >>>>>>>>
> >>>>>>>> 1. ET(2) = xx(5,2) : 253250. = 253250.000000000
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 2. ET(2) = xx(5,2) : 253250. = 253250.000010259
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 3. ET(2) = xx(5,2) : 253250. = 253249.999999988
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4132419437260 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941324E+08
> >>>>>>>> 4. ET(2) = xx(5,2) : 253250. = 253250.000048432
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 5. ET(2) = xx(5,2) : 253250. = 253249.999999872
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4177283437784 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941773E+08
> >>>>>>>> 6. ET(2) = xx(5,2) : 253250. = 253250.000071113
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 7. ET(2) = xx(5,2) : 253250. = 253249.999980115
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4453347441010 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.944533E+08
> >>>>>>>> 8. ET(2) = xx(5,2) : 253250. = 253250.000037298
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4082723436679 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.940827E+08
> >>>>>>>> 9. ET(2) = xx(5,2) : 253250. = 253249.999942706
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4082723436679 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.940827E+08
> >>>>>>>> 10. ET(2) = xx(5,2) : 253250. = 253249.999948703
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 11. ET(2) = xx(5,2) : 253250. = 253250.000007808
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.7283811474088 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.972838E+08
> >>>>>>>> 12. ET(2) = xx(5,2) : 253250. = 253250.000018146
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 13. ET(2) = xx(5,2) : 253250. = 253250.000001865
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 28.3742819315846 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.837428E+08
> >>>>>>>> 14. ET(2) = xx(5,2) : 253250. = 253249.999997296
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 15. ET(2) = xx(5,2) : 253250. = 253250.000000049
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 30.6548963582361 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -3.065490E+08
> >>>>>>>> 16. ET(2) = xx(5,2) : 253250. = 253250.000022870
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 17. ET(2) = xx(5,2) : 253250. = 253249.999999716
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.5326051451209 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.953260E+08
> >>>>>>>> 18. ET(2) = xx(5,2) : 253250. = 253250.000074328
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4165187437643 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941652E+08
> >>>>>>>> 19. ET(2) = xx(5,2) : 253250. = 253250.000049809
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4085059436707 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.940851E+08
> >>>>>>>> 20. ET(2) = xx(5,2) : 253250. = 253250.000019253
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 21. ET(2) = xx(5,2) : 253250. = 253250.000000189
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.8851075492403 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.988511E+08
> >>>>>>>> 22. ET(2) = xx(5,2) : 253250. = 253249.999997897
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4085059436707 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.940851E+08
> >>>>>>>> 23. ET(2) = xx(5,2) : 253250. = 253249.999975142
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.3961539435263 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.939615E+08
> >>>>>>>> 24. ET(2) = xx(5,2) : 253250. = 253250.000018324
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4085059436707 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.940851E+08
> >>>>>>>> 25. ET(2) = xx(5,2) : 253250. = 253249.999987073
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4165187437643 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941652E+08
> >>>>>>>> 26. ET(2) = xx(5,2) : 253250. = 253249.999980982
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4165187437643 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941652E+08
> >>>>>>>> 27. ET(2) = xx(5,2) : 253250. = 253249.999994645
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 28. ET(2) = xx(5,2) : 253250. = 253249.999962364
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4165187437643 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941652E+08
> >>>>>>>> 29. ET(2) = xx(5,2) : 253250. = 253249.999999921
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 30. ET(2) = xx(5,2) : 253250. = 253250.000000058
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 28.4019971319085 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.840200E+08
> >>>>>>>> 31. ET(2) = xx(5,2) : 253250. = 253250.000040348
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4085059436707 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.940851E+08
> >>>>>>>> 32. ET(2) = xx(5,2) : 253250. = 253250.000005245
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 33. ET(2) = xx(5,2) : 253250. = 253250.000005245
> >>>>>>>> ff(5,2) = ET(2)-OLD(5,2)-TSF(2)*DET(2) : 29.4126563437192 =
> >>>>>>>> 253250. - 253250.000000000 - 1.000000E-07 * -2.941266E+08
> >>>>>>>> 34. ET(2) = xx(5,2) : -848141. = -848141.388090847
> >>>>>>>> --------------------------------------------------------------------------
> >>>>>>>> Petsc Release Version 2.3.0, Patch 32, April, 26, 2005
> >>>>>>>> See docs/changes/index.html for recent updates.
> >>>>>>>> See docs/faq.html for hints about trouble shooting.
> >>>>>>>> See docs/index.html for manual pages.
> >>>>>>>> -----------------------------------------------------------------------
> >>>>>>>> ./SNESG3D2 on a linux-gnu named sethnx004.vac.com by yy26539 Mon Feb
> >>>>>>>> 27 14:21:13 2006
> >>>>>>>> Libraries linked from /home/yy26539/work/NISSE/petsc-2.3.0/lib/linux-gnu
> >>>>>>>> Configure run at Thu Oct 13 08:23:56 2005
> >>>>>>>> Configure options --with-cc=gcc --with-fc="f77 -N109"
> >>>>>>>> --download-mpich=1 --download-mpich-pm=gforker
> >>>>>>>> --download-f-blas-lapack=1 --with-shared=0
> >>>>>>>> -----------------------------------------------------------------------
> >>>>>>>> [0]PETSC ERROR: Caught signal number 8 FPE: Floating Point
> >>>>>>>> Exception,probably divide by zero
> >>>>>>>> [0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger
> >>>>>>>> [0]PETSC ERROR: likely location of problem given in stack below
> >>>>>>>> [0]PETSC ERROR: --------------- Stack Frames ---------------
> >>>>>>>> [0]PETSC ERROR: Note: The EXACT line numbers in the stack are not available,
> >>>>>>>> [0]PETSC ERROR: INSTEAD the line number of the start of the function
> >>>>>>>> [0]PETSC ERROR: is given.
> >>>>>>>> [0]PETSC ERROR: [0] SNES user function line 0 unknownunknown
> >>>>>>>> [0]PETSC ERROR: [0] SNESComputeFunction line 788 src/snes/interface/snes.c
> >>>>>>>> [0]PETSC ERROR: [0] SNESLineSearchCubic line 514 src/snes/impls/ls/ls.c
> >>>>>>>> [0]PETSC ERROR: --------------------------------------------
> >>>>>>>> [0]PETSC ERROR: User provided function() line 0 in unknown directory
> >>>>>>>> unknown file
> >>>>>>>> [0]PETSC ERROR: Signal received!
> >>>>>>>> [0]PETSC ERROR: !
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> Suggestions and tips are very welcome!
> >>>>>>>> /nisse
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> --
> >>>>>>>> Nils-Erik Svang�rd
> >>>>>>>> MSN: schweingaard at hotmail.com
> >>>>>>>> Skype: schweingaard
> >>>>>>>>
> >>>>>>>>
> >>>>>>>
> >>>>>>
> >>>>>>
> >>>>>> --
> >>>>>> Nils-Erik Svangård
> >>>>>> MSN: schweingaard at hotmail.com
> >>>>>> Skype: schweingaard
> >>>>>>
> >>>>>>
> >>>>>
> >>>>
> >>>>
> >>>> --
> >>>> Nils-Erik Svangård
> >>>> E-Mail: nilserik at gmail.com
> >>>> MSN: schweingaard at hotmail.com
> >>>> Skype: schweingaard
> >>>> Mobil: +46-(0)70-3612178
> >>>>
> >>>
> >>>
> >>> --
> >>> Nils-Erik Svangård
> >>> E-Mail: nilserik at gmail.com
> >>> MSN: schweingaard at hotmail.com
> >>> Skype: schweingaard
> >>> Mobil: +46-(0)70-3612178
> >>>
> >>>
> >>
> >
> >
> > --
> > Nils-Erik Svangård
> > E-Mail: nilserik at gmail.com
> > MSN: schweingaard at hotmail.com
> > Skype: schweingaard
> > Mobil: +46-(0)70-3612178
> >
> >
>
--
Nils-Erik Svangård
E-Mail: nilserik at gmail.com
MSN: schweingaard at hotmail.com
Skype: schweingaard
Mobil: +46-(0)70-3612178
More information about the petsc-users
mailing list