Your mistake is to force the parent to be GF(7). The parent is not the coefficient ring. Try sage: FormalSum? Type: type Base Class: <type 'type'> String Form: <class 'sage.structure.formal_sum.FormalSum'> Namespace: Interactive File: /home/john/sage-3.4.2/local/lib/python2.5/site-packages/sage/ structure/formal_sum.py
Constructor information: Definition: FormalSum(self, x, parent=Abelian Group of all Formal Finite Sums over Integer Ring, check=True, reduce=True) What were you trying to do? John Cremona On May 9, 1:00 pm, Christian Nassau <nas...@nullhomotopie.de> wrote: > Hi, > > FormalSum arithemtic appears to be broken when the parent is a Galois field: > > sage: a = FormalSum([(1,'x')],parent=GF(7)) > sage: 1*a > 0 > sage: a*1 > --------------------------------------------------------------------------- > TypeError Traceback (most recent call last) > > /home/cn/sg2/sage-3.4-linux-openSUSE_11.1_x86_64-x86_64-Linux/<ipython > console> in <module>() > > /home/cn/sg2/sage-3.4-linux-openSUSE_11.1_x86_64-x86_64-Linux/local/lib/python2.5/site-packages/sage/structure/element.so > in sage.structure.element.ModuleElement.__mul__ > (sage/structure/element.c:6599)() > > /home/cn/sg2/sage-3.4-linux-openSUSE_11.1_x86_64-x86_64-Linux/local/lib/python2.5/site-packages/sage/structure/coerce.so > in sage.structure.coerce.CoercionModel_cache_maps.bin_op > (sage/structure/coerce.c:5848)() > > TypeError: unsupported operand parent(s) for '*': 'Finite Field of size > 7' and 'IntegerRing' > > This is with Sage version 'Sage Version 3.4, Release Date: 2009-03-11'. > Is there a tracker where I should report this as a bug? > > Christian --~--~---------~--~----~------------~-------~--~----~ 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 URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
