77.3 ReflectionDegrees

ReflectionDegrees( W )

returns a list holding the degrees of W as a reflection group on the vector space V on which it acts. These are the degrees d_1,ldots,d_{dim V} of the basic invariants of W in SV, written in increasing order. They reflect various properties of W; in particular, their product is the size of W.

    gap> W := CoxeterGroup( "H", 4 );
    CoxeterGroup("H", 4)
    gap> ReflectionDegrees( W );
    [ 2, 12, 20, 30 ]
    gap> Size( W );
    14400 

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

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