# dynkinType(BasicList) -- constructing a Dynkin type

## Synopsis

• Function: dynkinType
• Usage:
dynkinType(L)
• Inputs:
• L, , of irreducible types that are lists containing a string of one letter from A to F and a positive integer, the rank
• Outputs:

## Description

 i1 : dynkinType({{"A",2},{"B",3}}) o1 = DynkinType{{A, 2}, {B, 3}} o1 : DynkinType

Note that low rank isomorphisms between classical groups are automatically used so that the letter is alphabetically minimal and the elementary types are irreducible (D2=A1xA1).

 i2 : dynkinType({{"A",2},{"B",1}}) o2 = DynkinType{{A, 2}, {A, 1}} o2 : DynkinType i3 : dynkinType({{"A",2},{"C",2}}) o3 = DynkinType{{A, 2}, {B, 2}} o3 : DynkinType i4 : dynkinType({{"A",2},{"D",2}}) o4 = DynkinType{{A, 2}, {A, 1}, {A, 1}} o4 : DynkinType