Hi Martin (and Sage-devel),
I discovered that polynomial substitution is badly inconsistent between the
symbolic ring and multivariate polynomials:
sage: R.<x,y> = QQ[]
sage: f = x + 2*y
sage: f.subs(x=y,y=x)
3*y
sage: var('x,y')
sage: f = x + 2*y
sage: f.subs(x=y,y=x)
2*x + y
See http://trac.sagemath.org/sage_trac/ticket/6873 for more and a proposal
about how to solve this.
William
--
William Stein
Associate Professor of Mathematics
University of Washington
http://wstein.org
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send an email to sage-devel@googlegroups.com
To unsubscribe from this group, send an email to
sage-devel-unsubscr...@googlegroups.com
For more options, visit this group at http://groups.google.com/group/sage-devel
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---
