The problem is indeed fixed by applying #13951 (which still needs reviewing).
Peter Op vrijdag 8 november 2013 17:35:01 UTC schreef John Cremona: > > On 8 November 2013 16:11, Georgi Guninski <guni...@guninski.com<javascript:>> > wrote: > > I am not an expert, but is it normal to get negative canonical > > height of a point on elliptic curve over number field? > > No, this is certainly an error. There is at least one outstanding > patch relating to heights over number fields (#13951) but also there > was a numerical instability problem fixed at #12509 which was not done > perfectly (I know, I did it) and that might be the issue here too. > > Heights are supposed to be independent of the base field. Your curve > and point are defined over Q where the height is computed as > 0.0324132522964454 -- this uses a completely different implementation > (in the pari library) which is more reliable, unfortunately. > > John Cremona > > > > > sage: Z1.<Z>=ZZ[];Nf.<v>=NumberField(Z**16-2);E=EllipticCurve(Nf,[-87, > 504, -40320, 0, 0]);P=E(0,0) > > sage: P.height() #not very fast > > -0.150688795814905 > > sage: P.height(precision=2000) > > -0.15068879581490624...<snip> > > > > Works on cloud.sagemath too. > > > > -- > > 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...@googlegroups.com <javascript:>. > > To post to this group, send email to > > sage-s...@googlegroups.com<javascript:>. > > > Visit this group at http://groups.google.com/group/sage-support. > > For more options, visit https://groups.google.com/groups/opt_out. > -- 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 post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/groups/opt_out.
