Changes between Version 1 and Version 25 of Ticket #10527

May 8, 2012, 2:39:46 AM (11 years ago)
Hugh Thomas

Okay, I agree, BB,1,1 should be undefined.

I'm confused about the notation you're using for some of the exceptional finite mutation type classes. The non-simply-laced finite mutation type mutation classes are classified in Felikson-Shapiro-Tumarkin, arXiv:1006.4276. They are elliptic root systems (F-S-T say this), contrary to what's in the package now, and as a result I would rather get them using Saito notation. But I don't see how the data for them match up with the data in F-S-T.

Here's another question: for the most part, the third parameter is redundant. I think the third parameter should only be used for the Kac convention (in affine root systems) and the Saito convention (in elliptic root systems).

The only other information you're using it for is when you want to indicate the check in the other convention for affine roots. But "check=true" would be easier to remember.

I also think it might be helpful to indicate references for the different conventions.

seems to be a pretty good reference for the affine diagrams using the Kac convention. And the convention Macdonald uses is recorded online at

Then there is possibly a more canonical reference for Saito than F-S-T.

It seems potentially confusing that "rank" is an argument for creating the object and also an attribute of the resulting object, but they aren't equal. I guess all I'm really asking for is that the parameter for creating the object should have a different name.

I haven't heard of types AE, BE, CE, DE before. BE, CE, and DE seem to be constructed on the same logic as BC, BD, etc, so it's pretty clear what they're doing, but I'm not sure that they're needed. AE seems to be constructed on a rather different logic; logically (to me) AE should just refer to the E-series. So in addition to wondering if it's needed, I'm not very happy with the name.


  • Ticket #10527

    • Property Dependencies changed from to #10349
    • Property Milestone changed from to sage-4.7.2
    • Property Keywords days38 added
    • Property Reviewers changed from to Hugh Thomas
  • Ticket #10527 – Description

    v1 v25  
    77['A', 3]
     10The current version of the patch is the one on the combinat server, not the one posted here.