I am working in version 4.1.1. It says that log only works when the base is a generator of the multiplicative group of the finite field.
For example if you work in GF(11), 5 is not a generator of the multiplicative group, although it is clear that 5^2 = 3 mod 11, but when using sage: sage: p = GF(11)(5) sage: p.multiplicative_order() 5 sage: b=GF(11)(3) sage: b.log(p) Traceback (most recent call last): ... ValueError: base (=5) for discrete log must generate multiplicative group On 6 March 2010 12:40, Alasdair <amc...@gmail.com> wrote: > What version of Sage are you using? - log works fine for me (version > 4.2.1): > > sage: F.<x>=GF(2^8,"x") > sage: (x+1).multiplicative_order() > 51 > sage: (x+1)^30 > x^5 + x^3 + x^2 > sage: (x^5+x^3+x^2).log(x+1) > 30 > > cheers, > Alasdair > > On Mar 5, 11:03 pm, yujia chiu <woodc...@gmail.com> wrote: > > Dear all, > > > > I tried to compute the logarithm of b based a in a finite field. But it > > seemed that the b.log(a) command in sage only works when a generates the > > multiplicative group of the finite field. Unfortunately, my a doesn't, > > although I already showed that b is indeed a power of a. > > Could you please tell me how to solve this problem? Thanks in advance. > > > > -- > > Kind Regards, > > Yujia Qiu > > -- > To post to this group, send email to sage-support@googlegroups.com > To unsubscribe from this group, send email to > sage-support+unsubscr...@googlegroups.com<sage-support%2bunsubscr...@googlegroups.com> > For more options, visit this group at > http://groups.google.com/group/sage-support > URL: http://www.sagemath.org > -- Kind Regards, Yujia Qiu -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
