On Tue, Nov 22, 2011 at 09:53:47PM +0000, Garth N. Wells wrote: > On 22 November 2011 21:50, Anders Logg <l...@simula.no> wrote: > > On Tue, Nov 22, 2011 at 09:33:25PM +0000, Garth N. Wells wrote: > >> On 22 November 2011 21:30, Anders Logg <l...@simula.no> wrote: > >> > On Tue, Nov 22, 2011 at 10:16:54PM +0100, Marie E. Rognes wrote: > >> >> On 11/22/2011 09:55 PM, Anders Logg wrote: > >> >> >On Tue, Nov 22, 2011 at 08:45:30PM +0000, Garth N. Wells wrote: > >> >> >> > >> >> >>On 21 Nov 2011, at 21:53, "Marie E. Rognes"<m...@simula.no> wrote: > >> >> >> > >> >> >>> > >> >> >>>On 21. nov. 2011, at 21:52, Anders Logg<l...@simula.no> wrote: > >> >> >>> > >> >> >>>>On Mon, Nov 21, 2011 at 08:46:13PM +0000, Garth N. Wells wrote: > >> >> >>>>>On 21 November 2011 13:07, Anders Logg<l...@simula.no> wrote: > >> >> >>>>>>On Sun, Nov 20, 2011 at 11:55:43PM +0100, Anders Logg wrote: > >> >> >>>>>>>On Sun, Nov 20, 2011 at 11:49:42PM +0100, Marie E. Rognes wrote: > >> >> >>>>>>>> > >> >> >>>>>>>>On 20. nov. 2011, at 23:31, Anders Logg<l...@simula.no> wrote: > >> >> >>>>>>>> > >> >> >>>>>>>>>Is anyone using the Function constructor that takes a vector > >> >> >>>>>>>>>as input > >> >> >>>>>>>>>argument? > >> >> >>>>>>>>> > >> >> >>>>>>>>>Function u(V, x); > >> >> >>>>>>>>> > >> >> >>>>>>>>Yes. > >> >> >>>>>>>Does it work? In parallel? > >> >> >>>>>>> > >> >> >>>>>>>Does it not work to instead use > >> >> >>>>>>> > >> >> >>>>>>> x = u.vector() > >> >> >>>>>>> > >> >> >>>>>>>? > >> >> >>>>>>> > >> >> >>>>>>>If you need it, we should keep it but add an error message that > >> >> >>>>>>>it > >> >> >>>>>>>doesn't work in parallel, unless it does... > >> >> >>>>>>Any more input on this? There are several options: > >> >> >>>>>> > >> >> >>>>>>1. Remove this constructor > >> >> >>>>>> > >> >> >>>>>>2. Throw an error when running in parallel > >> >> >>>>>> > >> >> >>>>>>3. Check that the input vector makes sense > >> >> >>>>>> > >> >> >>>>>>The last one is problematic since I don't see an easy way to > >> >> >>>>>>perform > >> >> >>>>>>the check, other than calling get_local and having it fail. > >> >> >>>>>> > >> >> >>>>>I haven't heard any reason why it can't be removed. We may need to > >> >> >>>>>fix > >> >> >>>>>assignment (re earlier discussion on assign) to just copy values > >> >> >>>>>and > >> >> >>>>>not the whole object so that a user can get the vector and then > >> >> >>>>>assign > >> >> >>>>>values to it without messing up the ghosting. > >> >> >>>>Sounds good, but I want to wait for Marie to comment before I remove > >> >> >>>>it. She is using it. > >> >> >>>> > >> >> >>>>Marie? Does it work for you to use x = u.vector()? > >> >> >>>> > >> >> >>>Probably. However removing the constructor would be changing parts > >> >> >>>of the basic interface, which I think is a bad idea. > >> >> >>> > >> >> >>>Add a warning if you want to deprecate it later. > >> >> >>> > >> >> >>Isn't the time to make an interface change now rather than later? > >> >> > >> >> I would say that the time to make an interface change before > >> >> 1.0 has passed: I see more value in sticking to > >> >> to what we have claimed, than in fixing this single instance. > >> >> > >> >> >True, but last time we discussed this was 1 hour or so before the > >> >> >release of 1.0-rc1. Now we have a whole week to 1.0-rc2... :-) > >> >> > > >> >> >Marie, can you check again if that constructor is necessary? > >> >> > >> >> I'm typically using it for the same as the dolfin la/eigenvalue demo > >> >> is using it for. > >> >> Do you have a replacement syntax available? > > > > Marie, I think this should work: > > > > u = Function(V) > > u.vector()[:] = x > > > > where x is the solution you get from the eigenvalue problem. > > > > Can you see if that works? > > > > It won't, because of a bad flaw in the vector assignment. It will > make u.vector()[:] a copy of x (which has the wrong parallel layout) , > when what we want is to assign just the values.
I thought you argued before that was the correct behavior? (When we discussed the subfunction assignment last week.) Is it much work to fix that before 1.0-rc2? -- Anders > Garth > > > > > > > > >> >> That said, I'm not going to lose any sleep over this. > >> > > >> > Is everyone ok with throwing an error that it doesn't work in > >> > parallel? > >> > > >> > >> I don't think that is ideal. > >> > >> I building now with the constructors commented out to see how many > >> changes would be required. > > > > _______________________________________________ Mailing list: https://launchpad.net/~dolfin Post to : dolfin@lists.launchpad.net Unsubscribe : https://launchpad.net/~dolfin More help : https://help.launchpad.net/ListHelp
