25 setxunit
7.5 setborder
90 setangle_repere
-2 10 setxrange
-5 5 setyrange
1 1 settkstep
.5 .5 setsubtkstep
2 2 setmkstep
ticks
subticks
marks
traceaxes
axesarrow
unites
/f {setxvar
#rpn#   max(x^2-3,0)
} def
gsave
   bleu
   1.5 setlinewidth
   continu
   {f} courbe
grestore