As I posted in sage-dev the problem actually is with the coefficients and I found a somewhat heavy handed solution:
sage: R.<u,v>=LaurentPolynomialRing(ZZ,2) sage: p=2*u**-1*v**-1+u*v sage: sum( R(c)*u**-exp[0]*v**-exp[1] for (exp,c) in p.dict().iteritems() ) 2*u*v + u^-1*v^-1 Andrew -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/groups/opt_out.
