On Nov 26, 2008, at 2:30 AM, Simon King wrote: > Hi! > > On Nov 26, 1:51 am, Alex Raichev <[EMAIL PROTECTED]> wrote: >> sage: F.<a>= NumberField(x^2-2) >> sage: a^2 >> 2 >> sage: a^2 in QQ >> True >> sage: a^2 in QQbar >> False >> sage: 2 in QQbar >> True > > A related observation: > sage: F.<a>=NumberField(x^2-2) > sage: QQ.is_subring(F) > True > sage: F.is_subring(QQbar) > False
This one should be false as QQbar comes with an embedding into CC, but F does not (in other words, there is no canonical embedding of F into QQbar). The a^2 in QQbar is a bug though. - Robert --~--~---------~--~----~------------~-------~--~----~ 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-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
