quiver3，空间向量场图

[x, y] = meshgrid(-2:0.2:2, -1:0.1:1);

z = x.*exp(-x.^2-y.^2);

[u, v, w] = surfnorm(x, y, z); %找出与曲面上各个点垂直的向量(u, v, w)，注意已经归一化

quiver3(x, y, z, u, v, w);

hold on, surf(x, y, z); hold off

axis equal

%colormap('default')

 

参考：http://anony3721.blog.163.com/blog/static/51197420119695025932/