Source
%% PhS
%% 

%% échelle et étendue de l'image
60 setxunit
-3.5 3.5  setxrange
-2.5 3.5 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


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%  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 dup mul 3 div t dup mul 2 mul sub  t -0.2 mul add 1 add neg 0 max
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





%% tracé du cercle

noir
1 setlinewidth


2.5 setlinewidth
coul1
continu
-4 4 settrange
{xdet} {ydet} courbeparam


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% texte
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
setTimesItalic



coul1
<latex>
$\mathcal{C}_{f^-}$
</latex>
-2 2.8 [3 dup] cctexlabel