> > What about 3.1.1 with just the fix for this, then possibly 3.2 or > > direct to 4.0. > > As you want. I don't like adding too many sub-release numbers, just > as > if someone fears jumping to next version. I remember some Sun > products > and Perl versions that end up with something like 5 release digits. > Well, I don't really care, so it can be 3.1.1 if people prefer that.
+1 on a 3.1.1 patch with that fix. I'm working on the same project as Gilles and Dim and assuming this is the only major problem found, it would be beneficial at least in my opinion to have release close to 3.1 that isolates that fix, before any major revamp. If other problems are found, this proposal fails, and we might as well wait for a 3.2 or 4.0 . -Hassan. ----- Original Message ----- > From: "Luc Maisonobe" <luc.maison...@free.fr> > To: "Commons Developers List" <dev@commons.apache.org> > Sent: Friday, December 28, 2012 7:35:15 PM > Subject: Re: [math] major problem with new released version 3.1 > > Le 28/12/2012 19:11, Phil Steitz a écrit : > > On 12/28/12 9:58 AM, Luc Maisonobe wrote: > >> Le 28/12/2012 17:51, Konstantin Berlin a écrit : > >>> Hi, > >>> > >>> I can understand Dimitri's frustration, it seems the optimization > >>> framework gets worse with every iteration. However, we should > >>> probably look forward and think about how to design it properly > >>> instead. > >>> > >>> Several times I brought out some problems and ideas about the > >>> package > >>> and it seems the only person who has an opinion is Gilles. > >> Several people contributed to the thread (see > >> <http://commons.markmail.org/thread/i6klmc2ytflb6qnt>), but as > >> Gilles > >> pointed out in one of the message, we lack an optimization expert. > >> I > >> sincerely would not want my opinion to be taken too seriously on > >> this, > >> so I only expressed what I could and did not decide anything by > >> myself > >> (only proposed to remove the wrong binding with > >> DerivativeStructure, > >> which has since been done). > >> > >>> I will list what I consider to be major problems > >>> 1) The OO design is bad, too much inheritance which could be > >>> handled > >>> better by interfaces, the structure has no relation to the actual > >>> way > >>> parts of optimizers can be mixed and matched. Input functions > >>> should > >>> also have clear inheritance structure and should return both the > >>> value, gradient, hessian in one function call. > >> I strongly agree with Konstantin here. Abstract classes allow to > >> add > >> methods without breaking compatibility (which is good), but they > >> also > >> have some drawbacks (we have seen one drawback with the > >> parameterized > >> classes a few months ago, and this huge hierarchy is another one). > >> So > >> there is no silver bullet and we keep trying to find the good > >> balance. > >> As far as I am concerned, I would prefer we get fewer abstract > >> classes, > >> we remove some intermediate level (I don't know which ones), and > >> we use > >> more delegation than inheritance. > >> > >>> 2) Incorrect handling of constraints. There are only something > >>> like 5 > >>> possible constraints possible in optimization, with each > >>> implementation of the solver handling some but not all. There is > >>> no > >>> need to this runtime approach, which creates incredible amount of > >>> confusion. All the possible constraints should be explicitly > >>> given in > >>> the parameters to a function call, there are only 5. In addition, > >>> constraints should be pre-processed a priori! So they should be > >>> an > >>> input to the constructor not to the optimization function call. > >> Our implementation for constraints is really limited (once again, > >> scarce > >> resources). What are the 5 types you consider? Simple/double > >> bounds on > >> parameters, linear/non-linear bounds and equality? > >> > >>> 3) Linear algebra package should be used as an interface and > >>> internally to increase performance for larger datasets. Data > >>> copying > >>> should be avoided as much as possible. > >> Yes, but this would require solving another sub-problem first: > >> having a > >> decent sparse linear algebra implementation, which we also lack. > >> Our > >> implementation for full matrices was also in a sorry state prior > >> to 3.0, > >> but now fortunately this has improved at least for systems up to a > >> few > >> thousands rows and columns (so at least we do make progress on > >> some points). > >> > >>> 4) Testing should be done on larger problems. > >> Yes. I guess there are some general well known problems for that, > >> so we > >> should get a few of them and implement them. We did implement a > >> number > >> of tests from Minpack, but they focused on difficult cases rather > >> than > >> on problem size. I think optimization has a good testing coverage, > >> but > >> clearly large size problems is a needed addition. > >> > >>> I know the response is that I am free to go implemented, but I > >>> think > >>> we should at least agree on design principles instead of pushing > >>> through your own ideas because the other person is too busy. The > >>> only > >>> discussion we ever had on this was between me and Gilles, > >>> everyone > >>> else disappeared. > >> Well, we tried to keep up as our skills allowed, and we were also > >> concerned with 3.1 being released at the same time. > >> > >> We have more time now than we had a few weeks ago. This is an > >> opportunity to restart the discussion. We can refrain from pushing > >> a new > >> release (despite I would like this bug fix to be released > >> officially) > >> and take some time to think calmly. We could also push 3.2 with > >> only the > >> fix > > > > What about 3.1.1 with just the fix for this, then possibly 3.2 or > > direct to 4.0. > > As you want. I don't like adding too many sub-release numbers, just > as > if someone fears jumping to next version. I remember some Sun > products > and Perl versions that end up with something like 5 release digits. > Well, I don't really care, so it can be 3.1.1 if people prefer that. > > Luc > > > > > Phil > >> and without any revamp and start thinking about 4.0 with a > >> redesign > >> of these two main area: optimization and sparse linear algebra. > >> > >> If you could contribute to this discussion understanding we are > >> not > >> experts of this field and we cannot do it by ourselves, it would > >> be great. > >> > >> best regards, > >> Luc > >> > >>> Thanks, Konstantin > >>> > >>> On Dec 28, 2012, at 11:27 AM, Phil Steitz <phil.ste...@gmail.com> > >>> wrote: > >>> > >>>> On 12/28/12 8:12 AM, Dimitri Pourbaix wrote: > >>>>> Luc, > >>>>> > >>>>>> So in order to make sure I understand your point, you would be > >>>>>> OK if I deprecate the non-diagonal weights, in which case > >>>>>> users > >>>>>> needing this would have to implement it themselves by > >>>>>> premultiplication (as both you and Konstantin seem to > >>>>>> propose)? > >>>>> Yes, exactly. > >>>>> > >>>>>> Sure, but for the record the feature was also a last minute > >>>>>> change. This was discussed on the list, and the final decision > >>>>>> was to add this feature despite the release was close. No > >>>>>> wonder we failed to test it thoroughsly. > >>>>> Last minute? I have been discussing this with Gilles for > >>>>> several months. > >>>> Relevant project discussion happens *on this list* > >>>>>> We don't expect our releases to be perfect. We do our best, > >>>>>> with the resources we have. > >>>>> I perfectly understand this but focusing those resources less > >>>>> on > >>>>> rules and more on real cases might help. > >>>> As stated before, you are more than welcome to *become* one of > >>>> these resources. > >>>> > >>>> Phil > >>>>> Regards, Dim. > >>>>> ---------------------------------------------------------------------------- > >>>>> > >>>>> > >>>>> > >> Dimitri Pourbaix * Don't worry, be > >> happy > >>>>> Institut d'Astronomie et d'Astrophysique * and CARPE > >>>>> DIEM. CP 226, office 2.N4.211, building NO * Universite > >>>>> Libre > >>>>> de Bruxelles * Tel : +32-2-650.35.71 Boulevard > >>>>> du > >>>>> Triomphe * Fax : +32-2-650.42.26 B-1050 > >>>>> Bruxelles * NAC: HBZSC RG2Z6 > >>>>> http://sb9.astro.ulb.ac.be/~pourbaix * > >>>>> mailto:pourb...@astro.ulb.ac.be > >>>>> > >>>>> --------------------------------------------------------------------- > >>>>> > >>>>> > >> To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > >>>>> For additional commands, e-mail: dev-h...@commons.apache.org > >>>>> > >>>>> > >>>> > >>>> --------------------------------------------------------------------- > >>>> > >>>> > >> To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > >>>> For additional commands, e-mail: dev-h...@commons.apache.org > >>>> > >>> > >>> --------------------------------------------------------------------- > >>> > >>> > >> To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > >>> For additional commands, e-mail: dev-h...@commons.apache.org > >>> > >>> > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > >> For additional commands, e-mail: dev-h...@commons.apache.org > >> > >> > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > > For additional commands, e-mail: dev-h...@commons.apache.org > > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > > This message and any attachments are intended for the use of the addressee or addressees only. 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