Simple version of WH

Below is a simplified version of the main procedure in hodgepack2. It first computes the Poincare polynomial, then picks out the needed coefficients and stuffs them into a list which is returned as the value of WH( W, d ).

  # WH( W, d ) = Hodge numbers of 

  WH := proc( W, d )   
     
      # Local variables
      # q+1 = order of pole for rational differential
      # n = dimension of variety
      # POP = Poincare polynomial
      # HL = list of Hodge numbers
      # k = degree in Jacobian ring = degree of term in Poincare polynomial
      # vdeg = weight of volume form in numerator
   
      local q, n, POP, HL, k, vdeg, kk;
   
      vdeg := sumlist(W);
      POP := pj(W,d);
      HL := [];
      for q from 0 to n do
         k := (q+1)*d - vdeg;
         HL := [ op(HL), coeff( POP, t, k) ];
      od;
      HL;
   
  end:


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12/27/97. Last modified by jac at 16:25 on 12/27/1997.