close(gcf)
clear all
x=[-7.5:0.5:7.5];
y=x;
[x,y]=meshgrid(x,y);
z=sin((x.^2+y.^2)/50).*exp(-(x/10).^2-(y/10).^2);
surf(x,y,z);
grid
clear all
x=[-7.5:0.5:7.5];
y=x;
[x,y]=meshgrid(x,y);
z=sin((x.^2+y.^2)/50).*exp(-(x/10).^2-(y/10).^2);
surf(x,y,z);
grid