On 2 July 2016 at 11:11, Jeroen Sijsling <sijsl...@gmail.com> wrote: > Hello, > > In Sage 7.2 I get the following error: > > R.<x> = PolynomialRing(QQ) > pol_rep = [1, -12, 70, -264, 757, -1872, 4258, -8796, 15922, -24900, 33886, > -40608, 43117, -40608, 33886, -24900, 15922, -8796, 4258, -1872, 757, > -264, 70, -12, 1] > K.<r> = NumberField(R(pol_rep)) > print K.subfield(K(1)) > > [...] > ValueError: 1 is not a root of the defining polynomial of Number Field in r0 > with defining polynomial x > > Replace the last line by print K.subfield(K(0)) and I get > > [...] > SignalError: Segmentation fault > > Replace pol_rep by [1, 1, 0, 1] and everything is fine though. > > Best, > Jeroen
Looking at the subfield() code reveals more basic problems: one = K(1) one.minpoly() x one.charpoly() x^24 # but one.charpoly(algorithm='sage').factor() (x - 1)^24 so there is a problem in getting the char poly of some number field elements via pari. This is serious! John > > -- > 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 sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at https://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. -- 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 sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
