25 setxunit
20 setborder
90 setangle_repere
-1 10 setxrange
-1 5 setyrange
1 1 settkstep
.5 .5 setsubtkstep
2 2 setmkstep
/A {6 3.5} def
/B {0.2 0.8} def
/W {-0.5 4.5} def
/E {9 -0.5} def
/S {0 2} def
/EB {3 -0.5} def
ticks
traceaxes
axesarrow
unites
/f {setxvar
#rpn#   2
} def
/g {setxvar
#rpn#   3-x
} def





<latex>
$W$
</latex>
W bctexlabel
<latex>
$\varepsilon$
</latex>
E brtexlabel
<latex>
$2\sigma F$
</latex>
S cltexlabel
<latex>
$2E_B$
</latex>
EB dltexlabel

gsave
   bleu
   .75 setlinewidth
   pointilles
 0 10  {f} courbe
grestore
gsave
   rouge
   .75 setlinewidth
   mixte
 0 3 {g} courbe
grestore
gsave
   bleu
   continu
<latex>
\begin{center}
$\mathbf{I}$\\
$\downarrow$
\end{center}
</latex>
   /hstep 10 store
   /hangle 0 store
 3 10  {f} Hachcourbe
noir
A drtexlabel
grestore
gsave
   noir
   continu
<latex>
$\mathbf{II}\longrightarrow$
</latex>
   /hstep 10 store
   /hangle 90 store
 1 3  {f} {g} Hachcourbes
B urtexlabel
grestore