Hi Guido First, sorry about sending to the old mailing list; I had forgotten about the new one. (I actually sent a copy to the new one, so sorry if you got this twice.)
Second - maybe I am misunderstanding terminology? Regularization, I thought, is making sure that a cell is no more than once more refined than any of its neighbors? I thought that, in 2D and 3D, prepare_coarsening_and_refinement () does this even with none of the flags set that you mentioned below..? I am talking about the case when all flags in the member smooth_grid are false. Regardless, in 1D, there is not the option to set any of those flags, and there is no regularization. The only thing that prepare_coarsening_and_refinement () does (according to the subversion) is make a call to fix_coarsen_flags. So I guess what I'm talking about is implementing the regularization step in prepare_coarsening_and_refinement() (STEP 6 according to the comments in the source) and then calling fix_coarsen_flags. (I'll go by the version 6.0 source, there's no need to add all the anisotropic refinement stuff, of course.) I assume there's no reason I can't do this? thanks dan Guido Kanschat wrote: > > Daniel, > > first, please replace the email address for the mailing list in your > browser: it is [EMAIL PROTECTED] The old address is obsolete. > > > > it seems to me, that the following smoothing algorithms make sense in 1D: > > / limit_level_difference_at_vertices > eliminate_unrefined_islands patch_level_1 > coarsest_level_1 eliminate_refined_inner_islands > eliminate_refined_boundary_islands > do_not_produce_unrefined_islands > Additionally, these should do the proper things in 1D as well. > > smoothing_on_refinement smoothing_on_coarsening > maximum_smoothing > > I think, what you describe is the first method only. If you want to > implement any of those, I suggest to read the source code as well as > the docs. > > On the other hand, the documentation is a bit bold there: if your > error estimator does not indicate refinement, yhere should be no > degradation of accuracy. That is, if it IS a reliable and efficient > estimator. Therefore, I'd suggest you try without smoothing. > > Best, > Guido > > /Daniel Goldberg wrote: >> Hi all >> >> I'm using a 1D model to try to test out an a posteriori estimator (I >> figure 1D will make it easier to identify whether the estimator is >> more effective than a generic one, and also I have some nice >> quasi-analytic 1D solutions). I realized that there is no mesh >> regularization implemented for the call to the 1-D version of >> prepare_coarsening_and_refinement(), which could degrade accuracy, >> right? >> >> I figure it should not be so difficult to implement the >> regularization step in 1D on my own, but I was wondering if I could >> get some assistance from someone who has tried it or thought about >> it? Would I do a similar reverse sweep, from highest down to (2nd) >> lowest level, to the one described in the docs, where at each level I >> check that if a cell's level after refinement would be 2 higher than >> that of its neighboring cell, then the neighboring cell is marked for >> refinement? And I noticed the fix_coarsen_flags() function is called >> even in 1D.. would it just need to be called once after the >> aforementioned sweep? >> >> Thanks very much, >> Dan >> > _______________________________________________
