#5306: [with patch, needs work] More number field ideal utilities
---------------------------+------------------------------------------------
 Reporter:  cremona        |       Owner:  was       
     Type:  enhancement    |      Status:  new       
 Priority:  major          |   Milestone:  sage-3.4.2
Component:  number theory  |    Keywords:            
---------------------------+------------------------------------------------

Comment(by cremona):

 On invertible_residues_mod_units() it is not easy to explain what this is:
 Let R be the ring of integers and I the ideal (self).  When there are no
 units given we iterate through {{{(R/I)^*}}}.  When there are units which
 generate some subgroup U of the unit group {{{R^*}}} (which in our
 applications will always be all of {{{R^*}}}) we want to iterate through
 elements of R representing the elements of {{{(R/I)^*/U_I}}}, where U_I is
 the image of U in {{{(R/I)^*}}}.

 Believe me, we need this for enumeration of cusps over number fields for
 the subgroup Gamma_0(n) where n is an ideal in GL(2,R)!.  Now I need to
 find a way of writing that succinctly in a docstring.  [The special case
 where U is [] will be of most use to most people, so we could provide a
 clear indication of how to use that.]

 On reduce:  I'll need to check whether the element being reduced also
 needs to be integral (I suspect so) and adapt the docstring if so.

-- 
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/5306#comment:5>
Sage <http://sagemath.org/>
Sage - Open Source Mathematical Software: Building the Car Instead of 
Reinventing the Wheel

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups 
"sage-trac" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to 
[email protected]
For more options, visit this group at 
http://groups.google.com/group/sage-trac?hl=en
-~----------~----~----~----~------~----~------~--~---

Reply via email to