On Thursday, May 12, 2016 at 4:56:54 AM UTC-7, Ralf Stephan wrote: > > On Thu, May 12, 2016 at 10:48 AM mmarco <mma...@unizar.es <javascript:>> > wrote: > >> But even if we implement expression.laurent_polynomial(), it wouldn't >> automatically allow conversion from SR to LaurentPolynomialRing, would it? >> > > Right, it's conversion on demand. > The thing that should probably be and probably is in place is:
var('x') R=LaurentPolynomialRing(QQ,'x') R(1+1/x) That way the user knows exactly what to expect. The interface that <symbolic expression>.laurent_polynomial(QQ) would implement would be more of the type "convert into a laurent polynomial in some suitable ring". That's very prone to unpredictable results, e.g.: var('x,y') (1/x+1/y).laurent_polynomial() (1/x+1/y-1/y).laurent_polynomial() ( (x+y)/(x*y) -1/y ).laurent_polynomial() so I would be hesitant to offer the routine in the first place. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.