Présentation de geomdiff3D_01.jps

%/width 500 def

%/height 300 def

%/border 7.5 def

/xmin -2 def
/xmax 2 def
/ymin -1.5 def
/ymax 1.5 def
/xtkstep 1 def
/ytkstep 1 def
/xsubtkstep .5 def
/ysubtkstep .5 def
/xmkstep 2 def
/ymkstep 2 def
jpegmode
/f {setxvar
    x Exp x neg Exp add 0.2 mul 0.25 add
} def
/g {setxvar
    x Exp x neg Exp add 0.2 mul neg -0.25 add 
} def
gsave
   noir
   1.5 setlinewidth
   continu
   -1.48 1.48 {f} Courbe
grestore
gsave
   noir
   1.5 setlinewidth
   continu
   -1.48 1.48 {g} Courbe
grestore

%tracé des ellipses aux extrémités 

/b {1.48 Exp 1.48 neg Exp add 0.2 mul 0.25 add} def
/a {0.25} def
1.5 0 a b ellipse
90 -90 -1.5 0 a b Ellipse
pointilles
-90 90 -1.5 0 a b Ellipse

%Tracé des ellipses internes

continu
/b' {0.5 Exp 0.5 neg Exp add 0.2 mul 0.25 add} def
/a' {0.2} def
90 -90 0.5 0 a' b' Ellipse
/b'' {0.8 Exp 0.8 neg Exp add 0.2 mul 0.25 add} def
/a'' {0.2} def
90 -90 0.8 0 a'' b'' Ellipse
pointilles
-90 90 0.5 0 a' b' Ellipse
-90 90 0.8 0 a'' b'' Ellipse

%Tracé du segment fléché "da"

/c {b' 0.1 add} def
/d {b'' 0.1 add} def
/C {0.45  c} def
/D {0.8  d} def
continu
C D (<->) line
/I {C D milieu} def
/J {0.5 -0.75} def 

%Définition du domaine à hachurer

/A {0.5  b' neg} def
rouge
A point
gsave
newpath
A smoveto
90 -90 0.5 0 a' b' Ellipse
0.5 0.8 {f} Courbe
90 -90 0.8 0 a'' b'' Ellipse
0.5 0.8 {g} Courbe
clip
%stroke

bleu hachure
grestore

setTimesItalic 
   noir  
   (da) I ultext
   rouge   
   (dA) J dtext