Hi all! On 2012-03-28, Nicolas M. Thiery <nicolas.thi...@u-psud.fr> wrote: > On Wed, Mar 28, 2012 at 10:04:44AM -0700, Mark Shimozono wrote: >> The fraction field of a Laurent polynomial ring S can't tell if one of >> its elements is in S.
I recall that about two years ago I had opened a ticket on inversion and fraction fields of power series rings. The bugs have been: A) sage: R.<x> = ZZ[[]] sage: (1/x).parent() Laurent Series Ring in x over Integer Ring sage: (x/x).parent() Power Series Ring in x over Integer Ring (Both parents are wrong, I believe, and to the very least the results are inconsistent) B) sage: (1/(2*x)).parent() <BOOM> C) sage: F = FractionField(R) sage: 1/x in F False If I remember correctly, I fixed all three bugs and even obtained a speed-up. Unfortunately, the patch bit-rotted and would not apply anymore. I am talking about trac ticket #8972, if someone likes to have a look. Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-combinat-devel" group. To post to this group, send email to sage-combinat-devel@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
