Opened 9 years ago
Closed 9 years ago
#15740 closed defect (fixed)
Better support for root systems which do not come from a Cartan type
Reported by:  Travis Scrimshaw  Owned by:  Sage Combinat CC user 

Priority:  major  Milestone:  sage6.2 
Component:  combinatorics  Keywords:  root systems 
Cc:  Sage Combinat CC user, Nicolas M. Thiéry  Merged in:  
Authors:  Travis Scrimshaw  Reviewers:  Frédéric Chapoton 
Report Upstream:  N/A  Work issues:  
Branch:  public/combinat/root_systems/non_typed15740 (Commits, GitHub, GitLab)  Commit:  d52d5a57997ed7b79f1ef79afe2471a3f4c9dba9 
Dependencies:  Stopgaps: 
Description (last modified by )
sage: d = DynkinDiagram() sage: d.add_edge(1,2,3) sage: d.add_edge(2,3) sage: d.add_edge(3,4,3) sage: d.cartan_matrix() [ 2 1 0 0] [3 2 1 0] [ 0 1 2 1] [ 0 0 3 2] sage: Q = d.root_system().root_lattice() sage: Q Root lattice of the Root system of type Dynkin diagram of rank 4 sage: al = Q.simple_roots() sage: al[1].reflection(al[2]) # Boom
Change History (10)
comment:1 Changed 9 years ago by
Authors:  → Travis Scrimshaw 

Branch:  → public/combinat/root_systems/non_typed15740 
Commit:  → 1c0a6c7549966eb34e76931d7833a16dc5d36a4c 
Description:  modified (diff) 
Status:  new → needs_review 
comment:2 Changed 9 years ago by
Looks good to me, but maybe one could add a test for the index_set correct behavior ?
comment:3 Changed 9 years ago by
It's implicitly there in the symmetrizer test, but I'll add an explicit test.
comment:4 Changed 9 years ago by
Commit:  1c0a6c7549966eb34e76931d7833a16dc5d36a4c → 05415fc560664b5b8eb5af0e55a655c3974aacc2 

Branch pushed to git repo; I updated commit sha1. New commits:
ac731d2  Trac 12141: finite algebras over fields

baa9c86  Merge branch 'u/pbruin/12141FiniteAlgebra' of trac.sagemath.org:sage into public/algebras/finite_algebra12141

9052b7c  Partial work on refactoring morphisms.

6badedb  Merge branch 'public/combinat/root_systems/non_typed15740' of trac.sagemath.org:sage into public/combinat/root_systems/non_typed15740

05415fc  Added doctest to Cartan matrix.

comment:5 Changed 9 years ago by
Commit:  05415fc560664b5b8eb5af0e55a655c3974aacc2 → d52d5a57997ed7b79f1ef79afe2471a3f4c9dba9 

comment:6 Changed 9 years ago by
After a little error with git (I forgot to base the branch off develop
), I've added the requested doctest.
comment:7 Changed 9 years ago by
Keywords:  root systems added 

Reviewers:  → Frédéric Chapoton 
Status:  needs_review → positive_review 
ok, good to go.
comment:9 Changed 9 years ago by
Milestone:  sage6.1 → sage6.2 

comment:10 Changed 9 years ago by
Resolution:  → fixed 

Status:  positive_review → closed 
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I fixed this by giving a method
symmetrizer
to the Dynkin diagrams. This uncovered another small bug in that the index set wasn't being taking from the Dynkin diagram (i.e. its vertices) which is also fixed here.New commits:
Added symmetrizer method to Dynkin diagrams and fixed the index set for the corresp. Cartan matrix.