Hi, Jean I used the method that you taught me. but unfortunately the results seems bad. And I'm not sure where the problem is including the transform between dofhandler iterator and triangulation iterator. So please take a look at my codes(two pieces of codes shown in the following figures) and tell me which one will be the right one. The first one is [image: 1.png] And the second one is [image: 2.png]
Thank you very much. Best, Toddy 在2021年11月13日星期六 UTC+8 上午10:31:07<Toddy Liu> 写道： > > Hello, Jean > > I'll look at the material and have a try. Thanks for your help > > Best, > Toddy > 在2021年11月13日星期六 UTC+8 上午1:03:04<Jean-Paul Pelteret> 写道： > >> Hi Toddy, >> >> It’s possible to convert a triangulation iterator to a DoF iterator using >> the technique described here: >> >> https://github.com/dealii/dealii/wiki/Frequently-Asked-Questions#can-i-convert-triangulation-cell-iterators-to-dofhandler-cell-iterators >> So one way would be just to loop over the triangulation and convert that >> to a velocity DoFHandler iterator and a pressure DoFHandler iterator. >> But it looks to me that you can convert between iterators in the same >> manner, so if you want you could also just use a standard loop over (DoF) >> cell iterators, and convert that primary iterator to the other kind. >> >> I hope that this helps! >> >> Best, >> Jean-Paul >> >> >> On 12. Nov 2021, at 04:22, Toddy Liu <[email protected]> wrote: >> >> Dear Deal.II community, >> >> I'm programming on modifying step 35 using Parallel computing with >> multiple processors using distributed memory. In step35, the tutorial >> program used "synchronous" iterator which consists of two iterators, one >> for velocity and the other for pressure. >> >> Now I'm struggling with the cell iterator when I assemble system. In step >> 40, it's enough to access cells using access like >> " const auto &cell : dof_handler.active_cell_iterators()". But how can I >> do this when the assemble_system needs two iterators (in my case one for >> velocity and the other for pressure)? >> >> Any advice or suggestions will be appreciated! >> Thank you. >> >> Best, >> Toddy >> >> -- >> 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 [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/dealii/cb916c9f-c84c-4f94-86b9-360e0e19c7b4n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/dealii/cb916c9f-c84c-4f94-86b9-360e0e19c7b4n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> >> >> -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/734d619d-d6c7-4e48-8ed1-879ea68c1344n%40googlegroups.com.
