\documentclass[a4paper]{article} \usepackage{pst-solides3d} \pagestyle{empty} \begin{document} %@AUTEUR: Juergen Gilg \psset[pst-solides3d]{viewpoint=10 9 15,SphericalCoor, Decran=40,lightsrc=5 5 10} \begin{pspicture}(-6,-11)(-6,7) \rput(0,0){ \defFunction[algebraic]{klein}(u,v){cos(u)*cos(v)/ (-2.*sqrt(0.965/3.-0.935/3.*((cos(u)^4+sin(u)^4)*cos(v)^4+ sin(v)^4))*cos((acos(-(-0.941/6.+0.374*((cos(u)^4+ sin(u)^4)*cos(v)^4+sin(v)^4)-1.309/6.*((cos(u)^6+ sin(u)^6)*cos(v)^6+sin(v)^6)-1.221*cos(u)^2*cos(v)^4* sin(u)^2*sin(v)^2)/sqrt(0.965/3.-0.935/3.*((cos(u)^4+ sin(u)^4)*cos(v)^4+sin(v)^4))^3)+pi)/3.)+0.8)}% {sin(v)/(-2.*sqrt(0.965/3.-0.935/3.*((cos(u)^4+sin(u)^4)*cos(v)^4+ sin(v)^4))*cos((acos(-(-0.941/6.+0.374*((cos(u)^4+ sin(u)^4)*cos(v)^4+sin(v)^4)-1.309/6.*((cos(u)^6+ sin(u)^6)*cos(v)^6+sin(v)^6)-1.221*cos(u)^2*cos(v)^4* sin(u)^2*sin(v)^2)/sqrt(0.965/3.-0.935/3.*((cos(u)^4+ sin(u)^4)*cos(v)^4+sin(v)^4))^3)+pi)/3.)+0.8)}% {sin(u)*cos(v)/(-2.*sqrt(0.965/3.-0.935/3.*((cos(u)^4+ sin(u)^4)*cos(v)^4+sin(v)^4))*cos((acos(-(-0.941/6.+0.374*((cos(u)^4+ sin(u)^4)*cos(v)^4+sin(v)^4)-1.309/6.*((cos(u)^6+ sin(u)^6)*cos(v)^6+sin(v)^6)-1.221*cos(u)^2*cos(v)^4*sin(u)^2* sin(v)^2)/sqrt(0.965/3.-0.935/3.*((cos(u)^4+sin(u)^4)*cos(v)^4+ sin(v)^4))^3)+pi)/3.)+0.8)} \psSolid[object=surfaceparametree, base=0 pi 2 mul pi neg 2 div pi 2 div, linecolor={[cmyk]{1,0,1,0.5}},linewidth=0.75\pslinewidth, ngrid=50, %RotY=90, RotX=-90, function=klein]% } \end{pspicture} \end{document}