On 8/28/07, Lisandro Dalcin <dalcinl at gmail.com> wrote:
> On 8/28/07, Matthew Knepley <knepley at gmail.com> wrote:
> > Yes, definitely. Go ahead and push it.
>
> I started to try this by implementing first on petsc4py with
> petsc-2.3.3-p4, by solving a trivial SPD diagonal system { A_ii =
> 1/(i+1) } with no PC and maxit=5. Below the results, some things seems
> broken.
>
> I think I will do the following:
>
> 1- Correct things in release-2.3.3, KSP's should not set
> KSP_DIVERGED_ITS if the convergence test returned other than
> KSP_CONVERGED_ITERATING (all GMRES's, RICHARDSON and TCQMR seems to do
> this). It also seems that I have to review KSP type GLTR (it stopped
> at iteration 4 and not 5, as it should).
>
> 2- Modify KSPSkipConverged and push on petsc-dev. Or perhpas can we
> also push this on release-2.3.3? The previous way is rather buggy,
> especially in conjunction with KSP_NORM_NO.Sounds good. I will ask Todd about gltr since it might be supposed to do something funny. You really do not want to look at it. Matt > Below the result (petsc4py is a nice tool for test/debug, isn't it?) > > > tfqmr - CONVERGED_ITS - iters: 5, ||r|| = 4.881889e-03, > x0,N-1=0.999996,9.978373 > minres - CONVERGED_ITS - iters: 5, ||r|| = 5.356222e-02, > x0,N-1=1.000009,9.701171 > fgmres - DIVERGED_ITS - iters: 5, ||r|| = 5.356222e-02, > x0,N-1=1.000009,9.701171 > stcg - CONVERGED_ITS - iters: 5, ||r|| = 5.629995e-02, > x0,N-1=1.000052,9.771470 > qcg - CONVERGED_ITS - iters: 5, ||r|| = 5.629995e-02, > x0,N-1=-1.000052,-9.771470 > cg - CONVERGED_ITS - iters: 5, ||r|| = 5.629995e-02, > x0,N-1=1.000052,9.771470 > lgmres - DIVERGED_ITS - iters: 5, ||r|| = 5.356222e-02, > x0,N-1=1.000009,9.701171 > cgne - CONVERGED_ITS - iters: 5, ||r|| = 7.192229e-02, > x0,N-1=1.000000,7.116166 > chebychev - DIVERGED_ITS - iters: 5, ||r|| = 2.591834e+00, > x0,N-1=0.636559,0.708271 > cgs - CONVERGED_ITS - iters: 5, ||r|| = 1.457830e-03, > x0,N-1=1.000000,9.994777 > bicg - CONVERGED_ITS - iters: 5, ||r|| = 5.629995e-02, > x0,N-1=1.000052,9.771470 > lsqr - CONVERGED_ITS - iters: 5, ||r|| = 4.612376e-01, > x0,N-1=1.000000,7.116166 > gltr - CONVERGED_ITS - iters: 4, ||r|| = 5.629995e-02, > x0,N-1=1.000052,9.771470 > tcqmr - DIVERGED_ITS - iters: 5, ||r|| = 0.000000e+00, > x0,N-1=1.000009,9.701171 > bcgs - CONVERGED_ITS - iters: 5, ||r|| = 2.566301e-03, > x0,N-1=0.999703,9.982615 > cr - CONVERGED_ITS - iters: 5, ||r|| = 5.356222e-02, > x0,N-1=1.000009,9.701171 > symmlq - CONVERGED_ITS - iters: 5, ||r|| = 5.629995e-02, > x0,N-1=1.000052,9.771470 > bcgsl - CONVERGED_ITS - iters: 5, ||r|| = 1.232695e-03, > x0,N-1=0.999988,9.999315 > lcd - DIVERGED_ITS - iters: 5, ||r|| = 5.629995e-02, > x0,N-1=1.000052,9.771470 > preonly - CONVERGED_ITS - iters: 1, ||r|| = 0.000000e+00, > x0,N-1=1.000000,1.000000 > gmres - DIVERGED_ITS - iters: 5, ||r|| = 5.356222e-02, > x0,N-1=1.000009,9.701171 > richardson - DIVERGED_ITS - iters: 5, ||r|| = 1.215430e+00, > x0,N-1=1.000000,4.095100 > > > > > > > > On 8/28/07, Lisandro Dalcin <dalcinl at gmail.com> wrote: > > > Does it make sense to change KSPSkipConverged to return > > > KSP_CONVERGED_ITS if iternum==maxit ? > > > > > > KSP_DIVERGED_ITS means convergence failure, but IMHO, KSPSkipConverged > > > should not imply convergence failure (this has implications in SNES). > > > > > > > > > -- > > > Lisandro Dalc?n > > > --------------- > > > Centro Internacional de M?todos Computacionales en Ingenier?a (CIMEC) > > > Instituto de Desarrollo Tecnol?gico para la Industria Qu?mica (INTEC) > > > Consejo Nacional de Investigaciones Cient?ficas y T?cnicas (CONICET) > > > PTLC - G?emes 3450, (3000) Santa Fe, Argentina > > > Tel/Fax: +54-(0)342-451.1594 > > > > > > > > > > > > -- > > What most experimenters take for granted before they begin their > > experiments is infinitely more interesting than any results to which > > their experiments lead. > > -- Norbert Wiener > > > > > > > -- > Lisandro Dalc?n > --------------- > Centro Internacional de M?todos Computacionales en Ingenier?a (CIMEC) > Instituto de Desarrollo Tecnol?gico para la Industria Qu?mica (INTEC) > Consejo Nacional de Investigaciones Cient?ficas y T?cnicas (CONICET) > PTLC - G?emes 3450, (3000) Santa Fe, Argentina > Tel/Fax: +54-(0)342-451.1594 > > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener
