>	plot3d( 4*x^2+y^2, x=-3..3, y=-4..4, axes=normal);

>	plot3d([ sqrt(z)/2*cos(t), sqrt(z)*sin(t), z], z=0..5, t=0..(2*Pi), axes=normal, view=[-3..3, -3..3, 0..5] );

>