100 setxyrapport
36 setxunit
7.5 setborder
90 setangle_repere
-1 10 setxrange
-100 600 setyrange
/quadrillagegray 0.4 def
0.5 setquadrillagexstep
50 setquadrillageystep
quadrillage
1 50 settkstep
.5 10 setsubtkstep
1 50 setmkstep
ticks
subticks
marks
traceaxes
axesarrow
unites
/f {setxvar
#rpn#   x*(22-2*x)*(18-2*x)
} def
gsave
   bleu
   .75 setlinewidth
   continu
  0  9 {f} Courbe
grestore