%% d'apres les donnees de
%% http://www.mathcurve.com/courbes3d/noeuds/noeudenhuit.shtml

-7 6 setxrange
-5 5 setyrange
50 setxunit

10 10 6 SetCamPos
0 0 0 SetCamView

-10 10 setxrange3d
-3 3 setyrange3d
2 setlinejoin
rouge

/g {
3 dict begin
   settvar
#rpn# 3*Cos(t)+5*Cos(3*t)
#rpn# 3*Sin(t)+5*Sin(3*t)
#rpn# Sin(5*t/2)*Sin(3*t) + Sin(4*t) -Sin(6*t)
end
} def

/g' {
3 dict begin
   settvar
#rpn# -3*Sin(t)-15*Sin(3*t)
#rpn# 3*Cos(t)+15*Cos(3*t)
#rpn# 2.5*Cos(5*t/2)*Sin(3*t) + 3*Sin(5*t/2)*Cos(3*t) + 4*Cos(4*t) -6*Cos(6*t)
end
} def

/g'' {
3 dict begin
   settvar
#rpn# -3*Cos(t)-45*Cos(3*t)
#rpn# -3*Sin(t)-45*Sin(3*t)
#rpn# -(2.5)^2*Sin(5*t/2)*Sin(3*t) + 7.5*Cos(5*t/2)*Cos(3*t) + 7.5*Cos(5*t/2)*Cos(3*t) - 9*Sin(5*t/2)*Sin(3*t) - 16*Sin(4*t) +36*Sin(6*t)
end
} def


% 0 pi 2 mul {g} CourbeR3
% stop

.1 setlinewidth
%/aretescachees false def

GetCamPos setlightsrc
%solidgridOff

0 pi 2 mul (g) .2 [400 5] newtube
dup [0 .3] solidputhuecolors
drawsolid**