X=-1:0.1:1; 
Y=-2:0.1:2;
[x,y]=meshgrid(X,Y);

z=-x.^6+2*x.^3+y.^2+2*y+1;

surf(x,y,z)

%alles grafikes parastaseis
contour(x,y,z)

surfc(x,y,z)

pcolor(x,y,z)