[K,H,P1,P2] = surfature(X,Y,Z) returns the gaussian curvature of a surface (K), mean curvature (H), and principal curvatures (P1,P2). The inputs (X,Y,Z) are 2D arrays corresponding to the surface being analyzed.

Example
[X,Y,Z] = peaks;
[K,H,P1,P2] = surfature(X,Y,Z);
surf(X,Y,Z,H,'facecolor','interp');
set(gca,'clim',[-1,1])