AFAIK, currently the function field object can not compute its genus (see below). I'm thinking about adding this feature in following few days. Now, there are two different approaches I can take, and I would like to know which one is more desirable for Sage community:
1. Sage can use singular to compute the genus, so we can write (essentially) a wrapper which compute the genus and make it a member of the function field class. 2. To implement the algorithm (for example the one in [1]) from scratch. Please, tell me which one is the more desirable approach. If anybody has any comment or has already the implementation please bring it up in the discussion. [1] Sendra, J. R. and Winkler, F. and Pérez-Díaz, S., Rational Algebraic Curves - A Computer Algebra Approach, Springer, 2007. sage: kx.<x> = FunctionField(QQ) sage: kxY.<Y> = PolynomialRing(kx, 'Y') sage: kxy.<y> = kx.extension(Y^2 - x^5 -1) sage: kxy Function field in y defined by Y^2 - x^5 - 1 sage: kxy.genus() --------------------------------------------------------------------------- AttributeError Traceback (most recent call last) /home/syd/Documents/RecherchePhD/Codes/sage/GrbBasis/<ipython console> in <module>() /home/syd/Programmes/sage-4.7.2/local/lib/python2.6/site-packages/sage/ structure/parent.so in sage.structure.parent.Parent.__getattr__ (sage/ structure/parent.c:6260)() /home/syd/Programmes/sage-4.7.2/local/lib/python2.6/site-packages/sage/ structure/parent.so in sage.structure.parent.getattr_from_other_class (sage/structure/parent.c:3110)() AttributeError: 'FunctionField_polymod_with_category' object has no attribute 'genus' sage: -- 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
