share/contrib/gentran/test/graeffe.f

   1       subroutine graeff(a,b)
   2 c
   3 c     --  Graeffe Root-Squaring Method   --
   4 c     --  to Find Roots of a Polynomial  --
   5 c
   6       b(1)=a(11)**2
   7       b(2)=2.0*a(9)*a(11)-a(10)**2
   8       b(3)=2.0*a(7)*a(11)-2.0*a(8)*a(10)+a(9)**2
   9       b(4)=2.0*a(5)*a(11)-2.0*a(6)*a(10)+2.0*a(7)*a(9)-a(8)**2
  10       b(5)=2.0*a(3)*a(11)-2.0*a(4)*a(10)+2.0*a(5)*a(9)-2.0*a(6)*a(8)+a(7
  11      . )**2
  12       b(6)=2.0*a(1)*a(11)-2.0*a(2)*a(10)+2.0*a(3)*a(9)-2.0*a(4)*a(8)+2.0
  13      . *a(5)*a(7)-a(6)**2
  14       b(7)=2.0*a(1)*a(9)-2.0*a(2)*a(8)+2.0*a(3)*a(7)-2.0*a(4)*a(6)+a(5)
  15      . **2
  16       b(8)=2.0*a(1)*a(7)-2.0*a(2)*a(6)+2.0*a(3)*a(5)-a(4)**2
  17       b(9)=2.0*a(1)*a(5)-2.0*a(2)*a(4)+a(3)**2
  18       b(10)=2.0*a(1)*a(3)-a(2)**2
  19       b(11)=a(1)**2
  20       return
  21       end