On Sat, Jan 1, 2022 at 4:01 PM Michael Beeson <profbee...@gmail.com> wrote: > > sage: d = 6 > > sage: p = d/2 > > sage: p > > 3 > > sage: is_prime(p) > > False # Huh?!!
The parent of p is QQ (the rational field). p is not a prime number of the **rational field**. You should coerce p to ZZ first. In retrospect, we probably should have just made is_prime throw an exception if the parent ring is a field, since the ring theory definition of prime number isn't very useful in a field. > > sage: is_prime(3) > > True > > sage: p==3 > > True > > This happens in version 8.7 and also in the current version (installed > yesterday) > > > -- > You received this message because you are subscribed to the Google Groups > "sage-support" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-support+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sage-support/9cb13872-298c-4463-b27d-b77ea288bfedn%40googlegroups.com. -- William (http://wstein.org) -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-support/CACLE5GDnGOFcb2OEO3OCczOuj-Yvzxa-k%3Dvx0xfoYog52Mogow%40mail.gmail.com.
