On Sat, Jun 11, 2011 at 12:19 PM, Simon King <simon.k...@uni-jena.de> wrote: > Hi!, > > At http://www.sagenb.org/home/pub/2813, I have published a worksheet > that aims at explaining how one can implement a new parent and take > advantage of both the category framework and the coercion model > (including construction functors). > > My approach was to implement fraction fields step by step, so that it > becomes clear what methods need to be provided for what purpose. I > also tried to explain the theoretical background. > > The worksheet covers: > * Choice of a base class for parents and elements > * How to implement basic arithmetics (_add_ versus __add__, etc) > * Category framework - why and how? > * Unique parents > * Basic coercion (trying to explain what structural properties > distinguish a coercion from any odd conversion, and how to implement > it) > * Advanced coercion (construction functors and pushout) > * Test suites. > > In order to be fully fuctional, the work sheet requires #8800, #9944 > and #9138 to be merged. While #8800 is merged in sage-4.7 and #9944 is > merged in sage-4.7.1, #9138 still needs review (hint-hint). > > However, I tried to work around the missing patches, so that the > worksheet is usable on www.sagenb.org (with sage-4.6).
I have updated sagenb.org to sage-4.7. I intend to keep sagenb more up to date these days... I may have broken something though, since http://www.sagenb.org/home/pub/2813 is empty. However, http://www.sagenb.org/home/pub/2814/ works. > > Of course, I'd appreciate feedback. I'd also appreciate if the > worksheet could be included into the documentation as a thematic > tutorial. > > In another thread, I suggested to proceed with documentation similar > than with spkgs: I believe that it is better to make preliminary > versions of tutorials available to the public (explicitly marking them > as preliminary or draft) than to wait a couple of months until someone > has provided a full review. In the best case, there is feed-back from > the public, so that one has a cumulative review. > > In particular, I think that the tutorials from the combinat branch > should be published soon as well. Namely, it seems to me that the > pedagogical approaches behind these texts and my text are orthogonal. > Having both available would give the user the opportunity to benefit > from what fits better to his or her respective learning type. > > What do you think? > > Best regards, > Simon > > -- > To post to this group, send an email to sage-devel@googlegroups.com > To unsubscribe from this group, send an email to > sage-devel+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org > -- William Stein Professor of Mathematics University of Washington http://wstein.org -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
