clc; 
clear all; 
close all;

t=0:pi/10:2*pi;
figure
[x,y,z]=cylinder(4*cos(t));
subplot(2,2,1); mesh(x,y,z)
subplot(2,2,2); ezmesh('x.*exp(-x.^2-y.^2)',40);
fh='x.*exp(-x.^2-y.^2)';
subplot(2,2,2); ezmesh(fh,40)
[x,y,z] = sphere;
subplot(2,2,3); plot3(x,y,z)
subplot(2,2,4); surf(x,y,z)