LIB "tst.lib"; tst_init(); ring A = 0,(x,y,z),dp; poly f = x2yz+xy2z+y2z+z3+xy; poly f1 = xy+y2-1; poly f2 = xy; ideal G = f1,f2; ideal S = std(G); S; reduce(f,G); G=f2,f1; reduce(f,G); reduce(f,S,1); reduce(f,S); tst_status(1);$