thanks! I thought it was related to the fact that the size is not a prime I didn't get that sort of troubles with a similar code for prime sizes
On Sun, Mar 15, 2009 at 2:34 PM, Alex Ghitza <[email protected]> wrote: > Judging from the error message "unable to coerce from a finite field other > than the prime subfield", it seems that in Martin's examples a coercion is > attempted from GF(p^a) to GF(p^b) where a>1. In David's example, the larger > field is GF(3^2) so any coercion would be coming from GF(3), hence not > covered by the error message. > > So I don't think it has to do with trac #5491. It is either a problem with > Sage finite fields, or with translating between Gap finite fields and Sage > finite fields. I'll have a closer look later today and open a ticket. > > Best, > Alex > > > On Mon, Mar 16, 2009 at 8:19 AM, David Joyner <[email protected]> wrote: >> >> This doesn't seem to happen for smaller values, >> >> sage: n = 2; q = 3 >> sage: H = PSL(n,q^2) >> sage: H.center() >> Permutation Group with generators [()] >> sage: n = 2; q = 2 >> sage: H = PSL(n,q^2) >> sage: H.center() >> Permutation Group with generators [()] >> >> so maybe the problem is related to >> http://trac.sagemath.org/sage_trac/ticket/5491? >> >> >> >> On Sun, Mar 15, 2009 at 3:07 PM, Martin Mereb <[email protected]> wrote: >> > >> > and >> > also got this problem >> > >> > n=3;q=4; >> > >> > H = SL(n,q^2); >> > H.center() >> > >> > Traceback (most recent call last): >> > File "<stdin>", line 1, in <module> >> > File "/home/sage/sagenb/sage_notebook/worksheets/Tincho/3/code/3.py", >> > line 10, in <module> >> > H.center() >> > File >> > "/home/sage/sage_install/sage-a/local/lib/python2.5/site-packages/SQLAlchemy-0.4.6-py2.5.egg/", >> > line 1, in <module> >> > >> > File >> > "/home/sage/sage_install/sage-a/local/lib/python2.5/site-packages/sage/groups/matrix_gps/matrix_group.py", >> > line 678, in center >> > self.__center = MatrixGroup([g._matrix_(F) for g in G]) >> > File >> > "/home/sage/sage_install/sage-a/local/lib/python2.5/site-packages/sage/interfaces/gap.py", >> > line 1131, in _matrix_ >> > entries = [[R(self[r,c]) for c in range(1,m+1)] for r in >> > range(1,n+1)] >> > File "finite_field_givaro.pyx", line 586, in >> > sage.rings.finite_field_givaro.FiniteField_givaro.__call__ >> > (sage/rings/finite_field_givaro.cpp:4680) >> > File >> > "/home/sage/sage_install/sage-a/local/lib/python2.5/site-packages/sage/interfaces/gap.py", >> > line 1248, in gfq_gap_to_sage >> > return F(K(g**e)) >> > File "finite_field_givaro.pyx", line 530, in >> > sage.rings.finite_field_givaro.FiniteField_givaro.__call__ >> > (sage/rings/finite_field_givaro.cpp:4005) >> > TypeError: unable to coerce from a finite field other than the prime >> > subfield >> > >> > > >> > >> >> > > > > -- > Alex Ghitza -- Lecturer in Mathematics -- The University of Melbourne -- > Australia -- http://www.ms.unimelb.edu.au/~aghitza/ > > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
