| LIB "bimodules.lib";
ring r = 0,(x,s),dp;
def R = nc_algebra(1,s); setring R; //1st shift algebra
ideal I = s^2, x*s, s^2 + 3*x*s;
isTwoSidedGB(I); // I is two-sided
==> 1
ideal J = s^2+x;
isTwoSidedGB(J); // J is not two-sided; twostd(J) = s,x;
==> 0
|