500 setwidth
250 setheight

-10 100 setxrange
-.25 1.25 setyrange

10 .25 setmkstep

traceaxes
axesarrow
marks

rouge
1.5 setlinewidth

xmin 40 {pop 0} (-\() Courbe
40 50 {pop .25} (*-\() Courbe
50 60 {pop .75} (*-\() Courbe
60 xmax {pop 1} (*-) Courbe