Source
``````%% PhS
%%

%% échelle et étendue de l'image
50 setxunit
-3.5 3.5  setxrange
-0.5 4.5  setyrange
/xgauche -6 def    %% c'est la limite gauche de l'image
/xdroite 6 def     %% c'est la limite droite de l'image
/ybasse  -4 def    %% c'est la limite basse de l'image
/yhaute  4 def     %% c'est la limite haute de l'image

10 4 point

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%  DANGER !! Il ne faut pas utiliser de variables
%%  DANGER !! qui commence par les lettres :
%%  DANGER !! xmin, xmax, ymin et ymax...
%%  DANGER !! Utiliser x_min, y_min...
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%% plages initiales pour les paramètres (peuvent être modifiées pour chaque fonctions tracées
/x_min -5 def
/x_max 5 def
/t_min -9 def
/t_max 9 def

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% procédures
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%% on donne ici x(t)
/xdet {
1 dict begin
/t exch def
t
end
} def

%% on donne ici y(t)
/ydet {
1 dict begin
/t exch def
t dup mul
end
} def

%% dessine un bout de droite
/bddroite { %% Ax Ay Bx By kg (=proportion vers A) kd (=prop vers B)
8 dict begin
/kd exch def
/kg exch def
/By exch def
/Bx exch def
/B {Bx By} def
/Ay exch def
/Ax exch def
/A {Ax Ay} def
gsave
[A A B vecteur kg mulv addv A A B vecteur kd mulv addv] ligne
grestore
end
} def

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% définitions des couleurs
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

/coul1 {120 255 div 70 255 div 9 255 div setrgbcolor} def

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% tracés
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%% tracé des axes et du point Origine
1 setlinewidth
15 setfontsize
noir
continu
traceaxes
marks
tracerepere

3 setlinewidth
coul1
0 3 settrange
{xdet} {ydet} courbeparam

[-5 0 0 0] (-) ligne

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% texte
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
setTimesItalic``````