Fix Sage's Brill-Noether

See the files

in the Sage install. Note this in the funciton riemann_roch_space (in

        The following example illustrates that the Riemann-Roch space
        function in Singular doesn't *not* work correctly.
            sage: R.<x,y,z> = GF(5)[]
            sage: f = x^7 + y^7 + z^7
            sage: C = Curve(f); pts = C.rational_points()
            sage: D = C.divisor([ (3, pts[0]), (-1,pts[1]), (10, pts[5]) ])
            sage: C.riemann_roch_basis(D)    # output is random (!!!!)
            [x/(y + x), (z + y)/(y + x)]
        The answer has dimension 2 (confirmed via Magma). But it varies
        between 1 and quite large with Singular.

There is a wiki page about general function fields issues in Sage.

days23.5/projects/brillnoether (last edited 2010-07-15 17:02:02 by was)