DynkinType -- the class of Dynkin Types

Description

A Dynkin Type is a list of items representing Dynkin types of irreducible root systems. These types are a string (the letter representing the family A, B, C, D, E, F or G) and an integer, the rank.

i1 : R=rootSystemB(4)++rootSystemA(6)

o1 = RootSystem{...8...}

o1 : RootSystem

i2 : dynkinType(R)

o2 = DynkinType{{A, 6}, {B, 4}}

o2 : DynkinType

Methods that use an object of class DynkinType :

dynkinExponents(DynkinType) -- the exponents of the Dynkin type
DynkinType ++ DynkinType -- the disjoint union of Dynkin Types
DynkinType == DynkinType -- the equality of Dynkin Types
numberOfPositiveRoots(DynkinType) -- the number of positive roots
rootSystem(DynkinType) -- the root system of a given type

For the programmer

The object DynkinType is a type, with ancestor classes BasicList < Thing.