%krivky a plochy

figure(1)
ezplot('(x^2+y^2)^2-(x^2-y^2)',[-1, 1, -1, 1])

figure(2)
ezplot('2*cos(t)*(1-cos(t))','2*sin(t)*(1-cos(t))',[0,2*pi])


figure(3)
a=1.5;
b=1.5;
c=1;
x=[num2str(a),'*cos(u)'];
y=[num2str(b),'*cos(v)+',num2str(a),'*sin(u)'];
z=[num2str(c),'*sin(v)'];
ezsurf(x,y,z,[0 2*pi 0 2*pi])

figure(4)
t=0:pi/10:2*pi;
[X,Y,Z]=cylinder(2+sin(t).*cos(t));
surf(X,Y,Z)
axis tight square