Vincent, I did read your email, which is very good. Thank you for posting. Unfortunately it is too focused for my taste. I would like to solve the generic problem of how to put in semantic information in sage first. Many might say let's solve one problem first, but in my mind it is already three times that this problem is appearing: - LMFDB - findstat - category framework That's why people who were at Edinburgh were invited.
I am looking for a generic solution, and to help with this I have started writing a document that is read only here: https://etherpad.mozilla.org/ep/pad/view/ro.Gzkl7YR-2gG/latest I am not writing this document at this exact moment, because I have a pressing deadline until Sunday. I am willing to devote much more time for this then. This is not an empty comment, in some ways my pressing deadline of Sunday is because I am already working on this. My timing is slightly affected, because in the back of my head I knew I just had to wait for the next flare up of this discussion on the list to get another discussion started, but this time backed up with concrete elements. Anyone who would like to help me add constructive material to the document is welcome to do so, just ask me for the link. @Christian: a generic, better, query engine might be build outside of findstat if the findstat group is too focused on their particular use case. Believe me, findstat is as far as I can tell baby case compared to LMFDB. But it has the merits of trying a more viable approach in my mind. I certainly don't want to develop anything without explicitly telling findstat about it. Paul Paul-Olivier Dehaye SNF Professor of Mathematics University of Zurich skype: lokami_lokami (preferred) phone: +41 76 407 57 96 chat: pauloliv...@gmail.com twitter: podehaye freenode irc: pdehaye On Wed, May 28, 2014 at 11:54 AM, Vincent Delecroix < 20100.delecr...@gmail.com> wrote: > Hi Christian, > > 2014-05-28 11:32 UTC+02:00, Christian Stump <christian.st...@gmail.com>: > >> It seems that actually nobody read my initial post on that thread... so > >> let me repeat > > > > I did -- but didn't really have any qualified contribution... > > > >> But the semantic has to be implemented at the level of maps not at the > >> level of methods. > > > > could you explain what you mean there (maybe using your example of the > > number of descents of a permutation). > > A method ( = a Python function) is not a Sage Map ( = a Python object > that model a mathematical function). I would like first to convert the > method into a map > {{{ > from sage.categories.map import Map > class NumberOfDescents(Map): > def __init__(self): > Map.__init__(Permutations(), NonNegativeIntegers()) > > def _call_(self, p): > return Integer(p.number_of_descents()) > }}} > The above example is already non-trivial since it specifies a domain > and a codomain (which is different from the parent of the image of an > element): > {{{ > sage: nod = NumberOfDescents() > sage: p = Permutation([3,2,1]) > sage: nod(p) > 3 > sage: nod(p).parent() is NN > False > }}} > The second step would be to think how to add semantic to the map. Part > of is already managed by the axioms/categories (for example a Morphism > between GradedSets preserve the grading). But there is nothing for > injectivity/surjectivity or more subtle properties. > > It would make more sense to register actual maps as above. > > Vincent > > -- > You received this message because you are subscribed to the Google Groups > "sage-combinat-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-combinat-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-combinat-de...@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-combinat-devel. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
