Julie, There is a tutorial in progress https://github.com/dealii/dealii/pull/11953 that is based on step-15 but uses KINSOL <https://dealii.org/developer/doxygen/deal.II/classSUNDIALS_1_1KINSOL.html>. KINSOL is a package dedicated to non-linear solve. It's probably worth using it in complicated cases like yours.
Best, Bruno On Thursday, April 15, 2021 at 6:08:30 AM UTC-4 j.y.m...@rug.nl wrote: > Dear all, > > I am trying to solve a p-Laplace Dirichlet problem with zero boundary and > used step-15 as the base. The code works well for p=1.1-2.9 with Newton and > standard linesearch procedure. But when p>=3 the program diverges, > continuation method brought me to p=2.99 but not beyond. Recently I have > used the LineMinimization class and got this error after a few iterations: > > using poly_fit and these param: > const double a1 = 1.0; > const double eta = 0.9; > const double mu = 1e-4; > const double a_max = 1.25; > const double max_evals = 100; > const bool debug_output = true; > > -------------------------------------------------------- > An error occurred in line <457> of file > </home/user/deal.ii-candi/deal.II-v9.1.1/include/deal.II/optimization/line_minimization.h> > > in function > NumberType dealii::LineMinimization::poly_fit(NumberType, NumberType, > NumberType, NumberType, NumberType, NumberType, const > dealii::FiniteSizeHistory<NumberType>&, const > dealii::FiniteSizeHistory<NumberType>&, const > dealii::FiniteSizeHistory<NumberType>&, std::pair<_FIter, _FIter>) [with > NumberType = double] > The violated condition was: > bounds.first < bounds.second > Additional information: > Incorrect bounds > > I have looked into the source code and understood these bounds are meant > for the sectioning and bracketing intervals. I tried different settings of > the param and still get this error. I am running out of ideas how to debug > this... > > Any help is highly appreciated. > > Thanks a lot and best wishes, > Julie > > > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to dealii+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/e2018a73-b617-456b-bae1-f84abdccffe2n%40googlegroups.com.
