> g_c[2,3]:=diff(x,theta)*diff(x,phi)+diff(y,theta)*diff(y,phi)+diff(z,theta)*
> diff(z,phi):
> g_c[3,3]:=diff(x,phi)*diff(x,phi)+diff(y,phi)*diff(y,phi)+diff(z,phi)*diff(z,phi):
> g:=simplify(create([-1,-1],eval(g_c)));

2.2 Calculation of the operators

Obtaining the orthonormal basis

> restart;
> with(DifferentialGeometry):with(Tensor):with(Tools):
> DGsetup([r,theta,phi],M):
> Basis:=evalDG(1*D_r,1/(r)*D_theta,1/(r*sin(theta))*D_phi]);

> Commutators:=FrameData(Basis,N);

> DGsetup(Commutators,verbose);