On Thursday, 7 March 2019 23:35:15 UTC-5, Wolfgang Bangerth wrote: > > On 3/7/19 7:45 AM, Bruno Blais wrote: > > > > However, my GMRES stops very quickly after a certain number of newton > > iteration with the following : AztecOO::Iterate error code -4: GMRES > > Hessenberg ill-conditioned > > This is surprising and suggests that something is wrong with the matrix, > not > the right hand side. At least that's what I think this probably means. Did > you > have the same error when you did not modify the right hand side? What > happens > if you just artificially create a right hand side that you know is in the > range, for example by picking a random vector and multiplying it by the > matrix? >
I did not have the same error when I did not modify the RHS. Which I also find very surprising. I also found that I did not get the same error if I modify the RHS, but that I also modify the Newton correction (if I project my newton correction such that corr = corr - P*corr) I will look at what you suggested, that's an extremely good idea, and get back at you. Thanks! > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: bang...@colostate.edu > <javascript:> > www: http://www.math.colostate.edu/~bangerth/ > > -- 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.
