%% PhS
%% 

%% échelle et étendue de l'image
50 setxunit
-0.5 10  setxrange
-1 6  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 -0.2 mul t dup mul add t 0.6 mul add 1 add
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
-2.2 1.715 settrange
{xdet 2.5 add} {ydet 1 add} courbeparam

-2.5 1.76 settrange
{xdet neg 5.97 add} {ydet -3.23 add 0.3 mul 4.2405 add} courbeparam

noir
[1.02 2.34    2.38 1.94   4.17 4.24] points

rouge
1 setlinewidth
[1.02 2.34 -0.8 -0.19 addv 1.02 2.34 0.8 0.19 addv] (<->) ligne
[2.38 1.94 -0.8 -0.19 addv 2.38 1.94 0.8 0.19 addv] (<->) ligne
[4.17 4.24 -0.8 -0.19 addv 4.17 4.24 0.8 0.19 addv] (<->) ligne


vert
pointilles
[0.3 0 0.3 0.85 8.47 2.68 8.47 0] (-) ligne


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


vert
<latex>
$a$
</latex>
0.3 -0.3 [3 dup] cctexlabel


<latex>
$b$
</latex>
9 -0.6 [3 dup] cctexlabel