Singular

LIB "ncloc.lib";
==> // ** redefining testNcloc (LIB "ncloc.lib";) ./examples/isDenom.sing:1
ring R = 0,(x,y,Dx,Dy),dp;
def S = Weyl();
setring S; S;
==> // coefficients: QQ
==> // number of vars : 4
==> //        block   1 : ordering dp
==> //                  : names    x y Dx Dy
==> //        block   2 : ordering C
==> // noncommutative relations:
==> //    Dxx=x*Dx+1
==> //    Dyy=y*Dy+1
// monoidal localization
ncloc loc;
poly g1 = x^2*y+x+2;
poly g2 = y^3+x*y;
list L = g1,g2;
loc = L;
poly g = g1^2*g2;
poly f = g - 1;
isDenom(g, loc);
==> 1
isDenom(f, loc);
==> 0
// geometrical localization
loc = ideal(x-1,y-3);
g = x^2+y-3;
f = (x-1)*g;
isDenom(g, loc);
==> 1
isDenom(f, loc);
==> 0
// rational localization
intvec v = 2;
loc = v;
g = y^5+17*y^2-4;
f = x*y;
isDenom(g, loc);
==> 1
isDenom(f, loc);
==> 0