%% gh
%% condition de cocyclicité
%% échelle et étendue de l'image
240 setxunit
-1.2 1.2 setxrange
-1.2 1.2 setyrange
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% définitions des couleurs
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
/coul0 {0 0 0 0.5 setcmykcolor} def %gris
/coul1 {noir} def
/coul2 {orange} def
/coul3 {rouge} def
/coul4 {bleu} def
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% le cercle
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
coul1
0 0 1 cercle
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% les points
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
coul3
/A {3 sqrt 2 div neg .5} def
A point
$A$
A [2.5 dup] ultexlabel
/B {0 1} def
B point
$B$
B [2.5 dup] urtexlabel
/C {0 1 neg} def
C point
$C$
C [2.5 dup] dctexlabel
/D {1 0} def
D point
$D$
D [2.5 dup] crtexlabel
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% les vecteurs
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
/arrowscale {2.5 dup} def
[A C] (-) ligne
[A D] (-) ligne
[B C] (-) ligne
[B D] (-) ligne
C A D .2 (=) tripointarc
C B D .2 (=) tripointarc