Hi! On 2014-09-18, Travis Scrimshaw <[email protected]> wrote: > Things like this have popped up in a few places, where doing things in a > fraction field over ZZ behaves much better than over QQ. I feel that > anytime we're constructing a fraction field from a ring R over a fraction > field F, we should make R over the ring used to construct F so reductions > (mainly gcd) are better behaved.
By coincidence, I have opened a ticket already, for the fact that 2/2*x is automatically simplified in Frac(ZZ[x]) but not in Frac(QQ[x]). Technically it is not a bug, since "simplification" usually means to divide by the gcd of numerator and denominator (which is 1 in QQ[x], but 2 in ZZ[x]). However, simplification could/should also involve a normalisation (when we are talking about fraction fields of polynomial rings over a field, then both numerator and denominator should be made monic). I suppose this would be enough to fix the hash problem. See trac ticket #16993 Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
