[sage-devel] Re: Help getting started with Hopf algebras in Sage

2010-10-05 Thread jvkersch
Hi Niles, Like John, I would like to be cc'd on any tickets about this. Apart from the obvious mathematical importance, I'm quite interested in finding out the right way of implementing these structures. I don't know if I'll be able to contribute immediately, but I'm looking forward to seeing ho

[sage-devel] Differential forms (Trac #9650)

2010-08-22 Thread jvkersch
Hi all, This is just a short notice to say that I've uploaded (a while back) a patch for support of differential forms to Sage, see: http://trac.sagemath.org/sage_trac/ticket/9650 Symbolic computations with tensors etc. have come up a number of times on this mailing list, so I thought maybe

[sage-devel] Re: Problems with TestSuite

2010-07-29 Thread jvkersch
Hi Simon and Florent, Let me answer you both in one post, since I think your solutions might be related. I agree with Simon that this is the offending line: tester.assert_(isinstance(self, self.parent().category().element_class)) Now, by adding the line Element = DifferentialForm to my p

[sage-devel] Problems with TestSuite

2010-07-27 Thread jvkersch
Hi all, I am looking for some understanding into the various test routines run by TestSuite. The problem is that I'm working on a new parent on which TestSuite fails, and I would like to understand whether this is due to me not understanding the relevant sage internals (very likely) or if I can j

[sage-devel] Re: Generators in Sage

2010-05-23 Thread jvkersch
Hi guys, Thanks for the insights. I knew that trying to define the generators in my original way was asking for trouble, but it's good to learn why. Right now, I just did the simple thing (which I should have done from the start): class DifferentialForms(Algebra): def __init__(..., coordinat

[sage-devel] Generators in Sage

2010-05-18 Thread jvkersch
Dear all, I would like to follow up on my differential forms class query (http:// groups.google.be/group/sage-devel/browse_thread/thread/ 2feef1f0be557585/75173b6c6f52450d) with a question about Sage programming/invoking style. If R^n has coordinates x, y, ... (or whatever), then the algebra of d

[sage-devel] Re: Differential forms

2010-05-14 Thread jvkersch
On 14 mei, 09:58, jvkersch wrote: > Meanwhile, I will also collect > the resources that people have posted in this thread, on a Wiki page > or so. See http://wiki.sagemath.org/tensorcalc Thanks for all the interesting pointers! All the best, Joris -- To post to this group, send

[sage-devel] Re: Differential forms

2010-05-14 Thread jvkersch
Hi Martin, On 13 mei, 12:52, Martin Rubey wrote: > Waldek just pointed me to a package by Seiler: > > http://axiom-wiki.newsynthesis.org/JetBundles This looks like an interesting package. While I was doing my PhD thesis I read many of W. Seiler's papers, and I was always intruiged by the compu

[sage-devel] Re: Differential forms

2010-05-14 Thread jvkersch
I think my previous reply to this message got eaten, so I'm sending it again. On 11 mei, 23:32, William Stein wrote: > > (...) should > > I start with a module over the Symbolic Ring, or is another ring more > > appropriate? > > Have you got anywhere reading the Sage developers guide? > > http://

[sage-devel] Re: Differential forms

2010-05-13 Thread jvkersch
On 12 mei, 01:11, Jason Grout wrote: > > I was wondering if there is any interest in a Sage package to compute > > with differential forms.   > > I am interested.  I'm particularly interested in applications to > teaching multivariable calculus. This raises the interesting possibility (which I

[sage-devel] Differential forms

2010-05-11 Thread jvkersch
Dear mailing list, I was wondering if there is any interest in a Sage package to compute with differential forms. Right now, I have the rudiments of a differential form class with the obvious operations (wedge product, exterior differential, Hodge star, ...) but I want to take this somewhat furth