i1 : A = (QQ [a,b,c]) [x, y, Dx, Dy, WeylAlgebra => {x=>Dx, y=>Dy}] o1 = A o1 : PolynomialRing, 2 differential variables
i2 : paramBpoly(a*x^2 + b*x*y + c*y^2, "quadratic") 2 1 o2 = {(S + 1) , (S + -)(S + 1)} 2 o2 : List