[petsc-users] petsc4py

[Lisandro Dalcin]

2010/9/29 Николай Кутузов <kutuzovnp at gmail.com>:
> Where can i get it? I've tried this one --
> http://code.google.com/p/petsc4py/source/browse/demo/ode/rober.py
>

This is from branch release-1.1, a  new release 1.1.2 is planned for
the weekend. As you can see from the output at the very end, SNES is
using matrix free. Note that I've not changed he code code, just
passed -snes_mf

What petsc4py and PETSc versions are you using?

[dalcinl at trantor petsc4py-release-1.1]$ python demo/ode/rober.py
-ts_view -snes_mf
TS Object:
  type: theta
    Theta=0.5
    Extrapolation=no
  maximum steps=100
  maximum time=1e+30
  total number of nonlinear solver iterations=203
  total number of linear solver iterations=311
  SNES Object:
    type: ls
      line search variant: SNESLineSearchCubic
      alpha=0.0001, maxstep=1e+08, minlambda=1e-12
    maximum iterations=50, maximum function evaluations=10000
    tolerances: relative=1e-08, absolute=1e-50, solution=1e-08
    total number of linear solver iterations=3
    total number of function evaluations=8
    KSP Object:
      type: gmres
        GMRES: restart=30, using Classical (unmodified) Gram-Schmidt
Orthogonalization with no iterative refinement
        GMRES: happy breakdown tolerance 1e-30
      maximum iterations=10000, initial guess is zero
      tolerances:  relative=1e-05, absolute=1e-50, divergence=10000
      left preconditioning
      using PRECONDITIONED norm type for convergence test
    PC Object:
      type: none
      linear system matrix = precond matrix:
      Matrix Object:
        type=mffd, rows=3, cols=3
            matrix-free approximation:
              err=1e-07 (relative error in function evaluation)
              Using wp compute h routine
              Computes normA
              Does not compute normU


-- 
Lisandro Dalcin
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