77.4 FakeDegrees

FakeDegrees( W, q )

returns a list holding the fake degrees of W as a reflection group on the vector space V on which it acts, evaluated at q. These are the graded multiplicities of the irreducible characters of W in the quotient SV/I where SV is the symmetric algebra of V and I is the ideal generated by the homogeneous invariants of positive degree in SV. The ordering of the result corresponds to the ordering of the characters in CharTable(W).

    gap> q := X( Rationals );; q.name := "q";;
    gap> FakeDegrees( CoxeterGroup( "A", 2 ), q );
    [ q^3, q^2 + q, q^0 ] 

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

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GAP 3.4.4
April 1997