On 4 May 2014 18:53, Jan Medina <janmedin...@gmail.com> wrote:
> Hi John
>
> John the discrete_log is the bsgs? in SAGE is not implemeted the Pohlig
> Helman algorithm?
One of the great things about Sage is that you have access to the
source code, so you can answer such questions yourself:
sage: search_src("Pohlig")
groups/generic.py:693: ALGORITHM: Pohlig-Hellman and Baby step giant step.
A long time ago (2008?) I implemented the bsgs, but since then there
have been improvements. One of these was that someone added
Pohlig-Helman. You can see exactly what is done in the file
src/sage/groups/generic.py
John
>
>
> 2014-05-04 10:41 GMT-05:00 John Cremona <john.crem...@gmail.com>:
>
>> On 4 May 2014 16:02, Jan Medina <janmedin...@gmail.com> wrote:
>> > Hi John, hi Simon.
>> >
>> > For example i want to construct the Bose.Chowla sequence with parameters
>> > p=839 y h=17, my question is what way its better to construct this
>> > sequence?.
>> >
>>
>> I have no idea, sorry.
>>
>> > I want to know this because i'm researching on the Chor Rivest system.
>> > Thus
>> > I need a good algorithm to solve the DLP.
>>
>> You are very welcome to implement better algorithms than Sage has
>> already and contribute them!
>>
>> John
>>
>> >
>> >
>> > 2014-05-04 9:34 GMT-05:00 Simon King <simon.k...@uni-jena.de>:
>> >>
>> >> Hi Jan, hi John,
>> >>
>> >> On 2014-05-04, John Cremona <john.crem...@gmail.com> wrote:
>> >> > On 4 May 2014 13:20, Jan Medina <janmedin...@gmail.com> wrote:
>> >> >> I wan to calculate log(\theta+i,\theta) for i in a finte field and
>> >> >> theta a
>> >> >> primtive element
>> >> >>
>> >> >
>> >> > You can see the documentation of this function like this:
>> >> >
>> >> > sage: F=GF(101)
>> >> > sage: a=F(3)
>> >> >
>> >> > sage: a.log?
>> >> >
>> >> > and even the code using a.log??
>> >>
>> >> I somehow have the impression that part of the problem is that John
>> >> thinks in terms of methods ( a.log() ), while Jan is thinking in terms
>> >> of functions ( log(a) ).
>> >>
>> >> Anyway, the documentation of the *function* "log" can be seen with
>> >> sage: log?
>> >> and the source code with
>> >> sage: log??
>> >>
>> >> And it seems to be the case that ultimately the function call log(a)
>> >> will end up with the method call a.log(). So, answering Jan's question:
>> >> Yes, if alpha is is an element of a finite field with primitive element
>> >> theta, then log(alpha,theta) is essentially the same as directly
>> >> calling
>> >> alpha.log(theta), and this the discrete logarithm.
>> >>
>> >> Best regards,
>> >> Simon
>> >>
>> >>
>> >> --
>> >> You received this message because you are subscribed to a topic in the
>> >> Google Groups "sage-support" group.
>> >> To unsubscribe from this topic, visit
>> >> https://groups.google.com/d/topic/sage-support/mbx4_5AN208/unsubscribe.
>> >> To unsubscribe from this group and all its topics, 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/d/optout.
>> >
>> >
>> > --
>> > 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/d/optout.
>>
>> --
>> You received this message because you are subscribed to a topic in the
>> Google Groups "sage-support" group.
>> To unsubscribe from this topic, visit
>> https://groups.google.com/d/topic/sage-support/mbx4_5AN208/unsubscribe.
>> To unsubscribe from this group and all its topics, 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/d/optout.
>
>
> --
> 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/d/optout.
--
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/d/optout.
