completeLinearSystemOnNodalPlaneCurve(Ideal,List) -- see completeLinearSystemOnNodalPlaneCurve -- Compute the complete linear system of a divisor on a nodal plane curve
imageUnderRationalMap(Ideal,Matrix) -- see imageUnderRationalMap -- Compute the image of the scheme under a rational map
Other things
distinctPlanePoints -- Generates the ideal of k random points in the coordinate ring $R$ of $\\P^{ 2}$