It presumably can't compute the class group, because of the proof=true
thing. Basically if you want a proven result, it is going to take
forever and will need more primes than Pari has precomputed.
It's not clear to me if SAGE is actually catching the error message,
or if it is just raising an exception because Pari did something it
wasn't expecting (i.e. print an error message).
Bill.
On 29 Dec, 20:27, mabshoff <[EMAIL PROTECTED]
dortmund.de> wrote:
> On Dec 29, 9:17 pm, [EMAIL PROTECTED] wrote:
>
>
>
> > Hello:
>
> > I am working at my Number Theory lectures and I have found a bug (?). This
> > is
> > the output:
>
> > /////////////////// SAGE 2.9.1 ///////////////////
> > sage: K.<a>=CyclotomicField(23)
> > sage: O=K.maximal_order()
> > sage: (2*O).factor()
> > *** Warning: large Minkowski bound: certification will be VERY long.
> > Traceback (most recent call last):
> > File "<stdin>", line 1, in <module>
> > File "/home/notebook/sage_notebook/worksheets/admin/3/code/13.py",
> > line 4, in <module>
> > exec compile(ur'(Integer(2)*O).factor()' + '\n', '', 'single')
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sympy/plotting/",
> > line 1, in <module>
>
> > File "sage_object.pyx", line 92, in
> > sage.structure.sage_object.SageObject.__repr__
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sage/structure/factor\
> > ization.py", line 187, in _repr_
> > t = str(self[i][0])
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > ld/number_field_ideal.py", line 218, in __repr__
> > return "Fractional ideal %s"%self._repr_short()
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > ld/number_field_ideal.py", line 235, in _repr_short
> > return '(%s)'%(', '.join([str(x) for x in self.gens_reduced()]))
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > ld/number_field_ideal.py", line 553, in gens_reduced
> > dummy = self.is_principal(proof)
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > ld/number_field_ideal.py", line 714, in is_principal
> > bnf = self.number_field().pari_bnf(proof)
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > ld/number_field.py", line 1464, in pari_bnf
> > self.pari_bnf_certify()
> > File
> > "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > ld/number_field.py", line 1497, in pari_bnf_certify
> > if self.pari_bnf(certify=False, units=True).bnfcertify() != 1:
> > File "gen.pyx", line 6474, in sage.libs.pari.gen._pari_trap
> > sage.libs.pari.gen.PariError: not enough precomputed primes, need
> > primelimit ~ (35)
>
> Hi Enrique,
>
> this looks like a bug to me. I have seen this issue discussed before,
> but I cannot find any ticket in our bug tracker that relates to it. So
> I am hoping for somebody more familiar with the pari interface to
> voice an opinion.
>
> Cheers.
>
> Michael
>
> > But if you type the following lines using gp interface, it works:
>
> > sage: K=gp.bnfinit(cyclotomic_polynomial(23))
> > sage: gp.idealfactor(K,2)
>
> > [[2, [1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
> > 0]~, 1, 11, [1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0,
> > 0, 0]~], 1; [2, [1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0,
> > 0, 0, 0, 0]~, 1, 11, [1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0,
> > 0, 0, 0, 0, 0]~], 1]
>
> > All the best,
>
> > Enrique
>
> > --------------------------------------------------------------------------
> > Mensaje enviado mediante una herramienta Webmail integrada en *El Rincon*:
> > ------------->>>>>>>> https://rincon.uam.es <<<<<<<<--------------
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to sage-devel@googlegroups.com
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at http://groups.google.com/group/sage-devel
URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/
-~----------~----~----~----~------~----~------~--~---
