[petsc-users] Tao iterations
Justin Chang
jychang48 at gmail.com
Tue Apr 21 09:48:43 CDT 2015
Time step 1:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0663148
Objective value=-55.5945
total number of iterations=35, (max: 2000)
total number of function/gradient evaluations=37, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 2:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0682307
Objective value=-66.9675
total number of iterations=23, (max: 2000)
total number of function/gradient evaluations=25, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 3:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0680522
Objective value=-71.8211
total number of iterations=19, (max: 2000)
total number of function/gradient evaluations=22, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 4:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0551556
Objective value=-75.1252
total number of iterations=18, (max: 2000)
total number of function/gradient evaluations=20, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 5:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0675667
Objective value=-77.4414
total number of iterations=6, (max: 2000)
total number of function/gradient evaluations=8, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 6:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.059143
Objective value=-79.5007
total number of iterations=3, (max: 2000)
total number of function/gradient evaluations=5, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 7:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0433683
Objective value=-81.3546
total number of iterations=5, (max: 2000)
total number of function/gradient evaluations=8, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 8:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0840676
Objective value=-82.9382
total number of iterations=0, (max: 2000)
total number of function/gradient evaluations=1, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 9:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0840676
Objective value=-82.9382
total number of iterations=0, (max: 2000)
total number of function/gradient evaluations=1, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
Time step 10:
Tao Object: 1 MPI processes
type: blmvm
Gradient steps: 0
TaoLineSearch Object: 1 MPI processes
type: more-thuente
Active Set subset type: subvec
convergence tolerances: fatol=0.0001, frtol=0.0001
convergence tolerances: gatol=0, steptol=0, gttol=0
Residual in Function/Gradient:=0.0840676
Objective value=-82.9382
total number of iterations=0, (max: 2000)
total number of function/gradient evaluations=1, (max: 4000)
Solution converged: estimated |f(x)-f(X*)|/|f(X*)| <= frtol
On Tue, Apr 21, 2015 at 9:28 AM, Jason Sarich <jason.sarich at gmail.com>
wrote:
> Hi Justin,
>
> what reason is blmvm giving for stopping the solve? (you can use -tao_view
> or -tao_converged_reason to get this)
>
> Jason
>
> On Mon, Apr 20, 2015 at 6:32 PM, Justin Chang <jychang48 at gmail.com> wrote:
>
>> Jason,
>>
>> I am using TaoGetSolutionStatus(tao,&its, ...) and it gives me exactly
>> what I want. However, I seem to be having an issue with blmvm
>>
>> I wrote my own backward euler code for a transient linear diffusion
>> problem with lower bounds >= 0 and upper bounds <= 1. For the first several
>> time steps I am getting its > 0, and it decreases over time due to the
>> nature of the discrete maximum principles. However, at some point my its
>> become 0 and the solution does not "update", which seems to me that
>> TaoSolve is not doing anything after that. This doesn't happen if I were to
>> use tron (my KSP and PC are cg and jacobi respectively).
>>
>> Do you know why this behavior may occur?
>>
>> Thanks,
>>
>> On Tue, Apr 14, 2015 at 9:35 AM, Jason Sarich <jason.sarich at gmail.com>
>> wrote:
>>
>>> Hi Justin,
>>>
>>> I have pushed these changes to the "next" branch, your code snippet
>>> should work fine there.
>>>
>>> Note that there is also available (since version 3.5.0) the routine
>>> TaoGetSolutionStatus(tao,&its,NULL,NULL,NULL,NULL,NULL) which will provide
>>> the
>>> same information
>>>
>>> Jason
>>>
>>> On Fri, Apr 10, 2015 at 6:28 PM, Justin Chang <jychang48 at gmail.com>
>>> wrote:
>>>
>>>> Whatever is convenient and/or follow the "PETSc" standards.
>>>> Something similar to SNESGetIterationNumber() or KSPGetIterationNumber()
>>>> would be nice. Ideally I want my code to look like this:
>>>>
>>>> ierr = TaoGetIterationNumber(tao,&its);CHKERRQ(ierr);
>>>> ierr = PetscPrintf(PETSC_COMM_WORLD, "Number of Tao iterations =
>>>> %D\n", its);
>>>>
>>>> Thanks :)
>>>>
>>>> On Fri, Apr 10, 2015 at 5:53 PM, Jason Sarich <jason.sarich at gmail.com>
>>>> wrote:
>>>>
>>>>> Hi Justin, I'll get this in. I assume that displaying the number of
>>>>> iterations with tao_converged_reason is what you are asking for in
>>>>> particular? Or did you have something else in mind?
>>>>>
>>>>> Jason
>>>>> On Apr 10, 2015 16:42, "Smith, Barry F." <bsmith at mcs.anl.gov> wrote:
>>>>>
>>>>>>
>>>>>> Justin,
>>>>>>
>>>>>> Sorry TAO simply doesn't even collect this information currently.
>>>>>> But yes we should definitely make it available!
>>>>>>
>>>>>> Jason,
>>>>>>
>>>>>> Could you please add this; almost all the TaoSolve_xxx() have a
>>>>>> local variable iter; change that to tao->niter (I'm guess this is suppose
>>>>>> to capture this information) and add a TaoGetIterationNumber() and the uses
>>>>>> can access this. Also modify at the end of TaoSolve() -tao_converged_reason
>>>>>> to also print the iteration count. At the same time since you add this you
>>>>>> can add a tao->totalits which would accumulate all iterations over all the
>>>>>> solves for that Tao object and the routine TaoGetTotalIterations() to
>>>>>> access this. Note that TaoSolve() would initialize tao->niter = 0 at the
>>>>>> top.
>>>>>>
>>>>>> Thanks
>>>>>>
>>>>>> Barry
>>>>>>
>>>>>>
>>>>>>
>>>>>> > On Apr 10, 2015, at 4:16 PM, Justin Chang <jchang27 at uh.edu> wrote:
>>>>>> >
>>>>>> > Hi all,
>>>>>> >
>>>>>> > Is there a way to generically obtain the number of Tao iterations?
>>>>>> I am looking through the -help options for Tao and I don't see any metric
>>>>>> where you can output this quantity in the manner that you could for SNES or
>>>>>> KSP solves. I am currently using blmvm and tron, and the only way I can see
>>>>>> getting this metric is by outputting -tao_view and/or -tao_monitor and
>>>>>> manually finding this number. I find this cumbersome especially for
>>>>>> transient problems where I would like to simply have this number printed
>>>>>> for each step instead of ending up with unnecessary info.
>>>>>> >
>>>>>> > Thanks,
>>>>>> >
>>>>>> >
>>>>>> > --
>>>>>> > Justin Chang
>>>>>> > PhD Candidate, Civil Engineering - Computational Sciences
>>>>>> > University of Houston, Department of Civil and Environmental
>>>>>> Engineering
>>>>>> > Houston, TX 77004
>>>>>> > (512) 963-3262
>>>>>>
>>>>>>
>>>>
>>>
>>
>
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