18 setfontsize
-5 5 setxrange
-2 2 setyrange

/f {
   tanh
} def

50 setxunit
[1 1 .5 .5 .1 .1] {orange} Quadrillage
.7 setlinewidth

tracerepere
marks

<tex>
$$
   y = \th x
$$
</tex>

/dx_boxit 3 def
/dy_boxit 3 def
/linearc .05 def
/fillstyle {jaune fill} def
boxit
-3 1 [2 dup] cctexlabel
   
1.5 setlinewidth
gsave
   bleu
   {f} courbe
grestore

setTimesItalic
   (O) O drtext