% Sestrojte graf funkce f(x,y) = x^2 + y^2
figure
xx = -5 : 0.05 : 5;
yy = -5 : 0.05 : 5;
[x y] = meshgrid(xx,yy);
z = x.^2 + y.^2;
mesh(x,y,z)


% Sestrojte graf funkce f(x,y) = sqrt(x^2 + y^2)
figure
xx = -5 : 0.05 : 5;
yy = -5 : 0.05 : 5;
[x y] = meshgrid(xx,yy);
z = sqrt(x.^2 + y.^2);
mesh(x,y,z)


% Sestrojte graf funkce f(x,y) = (x^2 + y^2)*sin(1./(x^2 + y^2))
figure
xx = -5 : 0.05 : 5;
yy = -5 : 0.05 : 5;
[x y] = meshgrid(xx,yy);
% vsimnete si, ze funkce neni v bode [0,0] definovana
z = (x.^2 + y.^2).*sin(1./(x.^2 + y.^2));
mesh(x,y,z)


% Sestrojte graf funkce f(x,y) = sqrt(|x*y|)
figure
xx = -5 : 0.05 : 5;
yy = -5 : 0.05 : 5;
[x y] = meshgrid(xx,yy);
z = sqrt(abs(x.*y));
mesh(x,y,z)