vanishing.asir

// Ex. Points=newmat(3,2,[[-1,0],[0,1],[1,0]]);

def get_vanishing_ideal(Points) {
    Size = size(Points);
    if (Size[1] != 2) error("Error: The number of columns must be 2");
    NumPoints = Size[0];
    Ideal = [x - Points[0][0], y - Points[0][1]];
    for (I = 1; I < NumPoints; ++I) {
        PointIdeal = [x - Points[I][0], y - Points[I][1]];
        Ideal = poly_ideal_intersection(Ideal, PointIdeal, [x, y], 0);
    }

    NumPolynomial = length(Ideal);
    MaxDegreeInIdeal = 0;
    for (IdealLoop = Ideal; IdealLoop != []; ) {
        D = poly_degree(car(IdealLoop));
        MaxDegreeInIdeal = D > MaxDegreeInIdeal ? D : MaxDegreeInIdeal;
        IdealLoop = cdr(IdealLoop);
    }
    print(["NumPolynomial: ", NumPolynomial, " MaxDegreeInIdeal: ", MaxDegreeInIdeal]);

    return Ideal;
}
end$