On Sun, 29 Oct 2006 03:10:55 -0700, Bill Hart <[EMAIL PROTECTED]> wrote: > I believe that there is no reason to have a default indeterminate x > defined when SAGE starts, any more. I know I was basically one of the > people advocating this, but Bill Page's principle of least surprise has > convinced me that I'm wrong. > > What I think *is* valuable, is being able to define: > > x = polygen() > > This is useful if one wants to introduce a placekeeping indeterminate. > Here x will still be a universal indeterminate.
I like that. I think I also proposed it. > But once you get rid of the default x that is introduced when SAGE > starts, then obviously R = PolynomialRing(ZZ) has to be illegal. That > is unless of course, you use this $.0 thing. I personally think SAGE > should refer to them as R.0, R.1, etc, but maybe that causes problems > somewhere else. > > Actually, this is one of the features of MAGMA that I abhor the most, > so if it were me, I would just make R=PolynomialRing(ZZ) illegal. If you test out sage-dev on sage.math, you'll find that I already made R=PolynomialRing(ZZ) illegal, since it seemed most natural to do so. > But I have to admit, there is also something unsettling about this. I don't think so. It's extremeley natural if you use any other serious programs for algebraic geometry besides MAGMA. In the other ones, there is never a way to define polynomial rings without saying what the generators are. > However, if we solve this problem, we will have removed one of the > biggest obstacles to new users that MAGMA currently presents. My impression is that this problem has already been solved by most programs *except* MAGMA. > Polynomials are totally fundamental things and anything we can do to > make them easier and more natural to use will be a huge benefit to > users of SAGE. I agree. William --~--~---------~--~----~------------~-------~--~----~ 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/ -~----------~----~----~----~------~----~------~--~---
