i1 : R = QQ[x1,x2,x3] o1 = R o1 : PolynomialRing
i2 : M = matrix {{ x1*x2*x3, x2^2*x3, x1*x2*x3^2 }} o2 = | x1x2x3 x2^2x3 x1x2x3^2 | 1 3 o2 : Matrix R <--- R
i3 : pommaretMultVar M o3 = {set {x3}, set {x3}, set {x3}} o3 : List