How to use the curvature.m package for Enneper's Surface

<<  curvature.m

x[u_, v_]  := 
       {u  -  u^3/3  +  u v^2,  v  -  v^3/3  +  v u^2,  
        u^2  -  v^2}

The first derivativesof x are

xu[x, u, v]

xv[x, u, v]

The second derivatives of x are

xuu[x, u, v]

xuv[x, u, v]

xvv[x, v, v]

The components of the metric are EE,  FF,  
    GG (rather than E,  F,  G) :

EE[x, u, v]

FF[x, u, v]

GG[x, u, v]

The unit normal vector is :

UU[x, u, v]

The components of the shape operator are ll,  mm,  
    nn (rather than l,  m,  n) :

ll[x, u, v]

nn[x, u, v]

mm[x, u, v]

The Gaussian curvature is

KK[x, u, v]

The Mean curvature is

HH[x, u, v]