> The options would then be None/False (=no embedding), True (standard > embedding), or any indexable.
I implemented the requested modifications, except for the new embeddings. This is: - the file sage.rings.universal_cyclotomic_field.all is lazily imported in sage.rings.all - the class UniversalCyclotomicField is imported in sage.rings.universal_cyclotomic_field.all and is the unique point of entry - the proposed ways to access the universal cyclotomics is through sage: UCF.<E> = UniversalCyclotomicField(); UCF Universal Cyclotomic Field endowed with the Zumbroich basis sage: E(5) E(5) sage: UCF.<zeta> = UniversalCyclotomicField() sage: zeta(5) zeta5 UCF.gen(5) zeta5 UCF.gen(5,2) zeta5^2 So far, I left open the implementation of the embedding. This is, the optional argument embedding only takes "True", "False", and "None". The problem I still have is that internally, the behaviour is always the same, independent of the embedding. This is to say that sage: E(5)+E(6) E(15) + E(15)^4 + E(15)^7 - E(15)^8 should always hold true. And I don't yet see (yet) how to ensure this - in particular, the embedding for prime n's does at least fix the embedding of all others. But I don't see if this is enough to ensure that everything works fine. There is also special behaviour for n being powers of 2, and I don't see how this influences the embeddings -- sorry for being ignorant here... Best, Christian -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To post to this group, send email to sage-devel@googlegroups.com. To unsubscribe from this group, send email to sage-devel+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel?hl=en.