%@AUTEUR: Juergen Gilg
\psset[pst-solides3d]{viewpoint=5 5 5,SphericalCoor,
	Decran=90,lightsrc=15 5 5}
\begin{pspicture}(-6,-11)(-6,7)
\rput(0,0){
\defFunction[algebraic]{klein}(u,v){2*(1-Euler^(u/(8*pi)))*cos(u)*(cos(v/2))^2}%
{2*(-1+Euler^(u/(8*pi)))*sin(u)*(cos(v/2))^2}%
{1-Euler^(u/(4*pi))-sin(v)+Euler^(u/(8*pi))*sin(v)}
\psSolid[object=surfaceparametree,
    base=0 pi 2 mul 0 pi 8 mul,
    linecolor=lightgray,linewidth=0.75\pslinewidth,
    incolor=gray,
    fillcolor=blue!40,
    ngrid=60,
%    RotY=55,
%    RotX=200,
    RotZ=-110,
    function=klein]%
}
\end{pspicture}