6-44.m

来自「MATLAB科学计算与工程分析源代码源程序5」· M 代码 · 共 7 行

clear
v = -2:0.2:2;
[x,y] = meshgrid(v);
z = x .* exp(-x.^2 - y.^2);
[px,py] = gradient(z,0.2,0.2);
contour(v,v,z), hold on, quiver(v,v,px,py), hold off