> Syntax error -- W is not defined. What is W? > Sorry. As Justin pointed out W is an arbitrary number field not equal to the rational numbers. > > > > sage: %timeit ((x+y+z)**3)(1/y,y,y**100) > > 10 loops, best of 3: 752 ms per loop <=== look here! > > sage: %timeit ((u+v+w)**3)(1/v,v,v**100) > > 10 loops, best of 3: 48.2 ms per loop <=== look here! > > It's not at all clear to me without further discussion and benchmarking > what the right optimization is so that rational functions over fields are > sufficiently fast. My point was that the above command over a number field is 15 times as fast as over the rationals. This is so counterintuitive that I think it is unacceptable.
> Basically, are you suggesting that one > not call reduce until, e.g., printing? There are several options. (1) declare reduce to be expensive so require the user to call it explicitly (this is the approach followed by maxima). As a refinement this behaviour could be triggered by a new flag for a ring element: gcd_is_expensive (e.g. for polynomials in several variables). (2) call reduce lazily and cache the result (this is what you are suggesting). Originally I had thought of (1) but now I think I like (2) better. Michel --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
