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--* Subject: [3] Expected SUP(#1), probable type substitution bug [rootsum.as][0.35.3]

--@ Fixed  by:  SSD   Tue Apr 18 10:05:44 EDT 1995 
--@ Tested by:  none 
--@ Summary:    Type substitution bugs fixed. eval takes (POLY K, L EQ POLY K). 


#include "axiom.as"

SUP ==> SparseUnivariatePolynomial
POLY ==> Polynomial
K ==> Integer

rootSum(fSUP:SUP K,gSUP :SUP K):SUP K ==
      x := new()$Symbol; y := new()$Symbol
      ff : POLY K := multivariate(fSUP,x); gg : POLY K := multivariate(gSUP,x)
      xx := x :: POLY K; yy := y :: POLY K
      phi := eval(ff,xx = yy); psi := eval(gg,xx = xx - yy)
      univariate resultant(phi,psi,y)