Hello, the following is not directly related but might still be of interest for you: as you can see in ticket #8327 and in
http://groups.google.com/group/sage-combinat-devel/browse_thread/thread/421cc6117d027dc9/9cce8b12b9c81d9f?#9cce8b12b9c81d9f we started to implement cyclotomic fields in the way it is done in GAP as a vector space with a distinguished basis called Zumbroich basis. Using this basis it is very fast to find the smallest CF a given linear combination of roots of unity lives in. This makes it easy to add or multiply roots of unities living in different CFs and consider the expression in the smallest CF it lives in. The project is still in an early phase but if it will turn out to work well it is maybe interesting to merge it with the version of cyclotomic fields already being used in sage. Comments and ideas are very welcome! Cheers, Christian -- 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