On Feb 13, 2008 2:09 PM, Nick Alexander <[EMAIL PROTECTED]> wrote: > > > On 13-Feb-08, at 12:28 PM, William Stein wrote: > > > > > On Feb 13, 2008 9:57 AM, Nick Alexander <[EMAIL PROTECTED]> wrote: > >> > >> > >> On 13-Feb-08, at 6:06 AM, John Cremona wrote: > >> > >>> > >>> I just discovered sage.rings.arith.discrete_log_generic(), not until > >>> after implementing a similar function for elliptic curves over > >>> finite > >>> fields (patch to be submitted before too long). I thought it was a > >>> pity that we cannot apparently use the same code for dlogs in an > >>> additive group (as in what I just wrote) and a multiplcative one (as > >>> in discrete_log_generic()). Could we? > >> > >> At this time, not easily. > > > > I think it would be trivial. Just pass in a function of two > > arguments called > > "mul" instead of using "*". It's the same way Python's sort works. > > (One should probably also pass in a pow function.) > > John also needs identity and inverses, which requires passing in > three or functions. Or, more likely a struct, which in an OO > language, I call an object. > > To me, that means you're writing a special purpose "abstract group" > wrapper for discrete logs, which is fine. But I believe the heavier > categorical stuff is intended to make doing this much more general > and pervasive throughout the system. Doing one instance ad-hoc is > easy; doing the general case is not easy (imho).
And doing the general case is easier if you do one instance :-) William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
