75.3 CartanName

CartanName( type )

CartanName( D )

takes as argument a type type as returned by CartanType. Returns the name of the root system with that type, which is the concatenation of the names of its irreducible components, with x added in between.

    gap> C := [ [ 2, 0, -1 ], [ 0, 2, 0 ], [ -1, 0, 2 ] ];;
    gap> CartanName( CartanType( C ) );
    "A2xA1"
    gap> CartanName( CartanType( CartanMat( "I", 2, 7 ) ) );
    "I2(7)" 

The argument to CartanName can also be a domain (i.e., D should be a record with a field operations.CartanName, and that function is then called with D as argument --- this is used for Coxeter groups and Coxeter cosets).

This function requires the package "chevie" (see RequirePackage).

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