Dragon, On Friday, September 9, 2016 at 7:02:15 AM UTC-4, dragniko...@gmail.com wrote: > > Thank you Denis. > > I tried that. The function log(c/(1-c)) looks like: > > > <https://lh3.googleusercontent.com/-98tPVjPUANE/V9KVjOfyXdI/AAAAAAAAAAM/OMFk_X10nP82jlxIfN1cEjtDx0Fvdf9lQCLcB/s1600/log.png> > and it is difficult to linearise in the whole range. And the assembled > matrices are solved out of deal.II so I definitely need to a weak form. >
To solve a non-linear problem, you basically have two choices: fixed-point iteration (https://en.wikipedia.org/wiki/Fixed-point_iteration) or, like Denis said, Newton's method (https://en.wikipedia.org/wiki/Newton%27s_method). Newton's method converges faster but is a little harder to implement. Best, Bruno -- 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. For more options, visit https://groups.google.com/d/optout.