The integer 'nu' needs to be a 'good degree' for the first parameter 'polynomialMatrix' that can be verified by doing isGoodDegree(polynomialMatrix,nu)
degreeImplicitEq computes the degree of the gcd of the maximal minors of the matrix representation of the homogeneous polynomials in 'polynomialMatrix' in degree 'nu', equivalently, the degree of determinant of the Z-complex associated to 'polynomialMatrix' in degree 'nu'. This is:
degreeImplicitEq(polynomialMatrix, nu) = degree(representationMatrix(polynomialMatrix,nu) that computes 'deg(det((Z(g0,g1,g2,g3))_nu))'
Precisely, 'degreeImplicitEq' returns an integer which is the degree of H^{deg(f)}.G, where H is the implicit equation, deg(f) is the degree of f={f0,f1,f2,f3}, and G is an extra factor that may appear.
i1 : S = QQ[s,t];
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i2 : f0 = s^2+s^3*t;
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i3 : f1 = s^3*t^6+1;
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i4 : f2 = s*t^2+2*s^3*t^5;
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i5 : f3 = s^2+s^3*t^6;
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i6 : degreeImplicitEq (teToricRationalMap{f0,f1,f2,f3},2)
o6 = 17
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