%%% les bornes sur les axes
/xmin -1 def
/xmax 3 def
/ymin -.5 def
/ymax 1.5 def
% ================== debut du dessin ====================

/sigma .5 def
/m 1.2 def

/f {
   m sub sigma div
   dup mul
   -2 div
   Exp
   1
   2 pi mul sqrt sigma mul   
   div mul
}  def

/f' {pop 0} def

/xA -1 def
/xB 1 def
/yA xA f def
/yB xB f def

traceaxes
unites
xticks
yticks
xmarks
ymarks
axesarrow

/tailletangente 1 def
/Mtgx m def
/Mtgy m f def
m (f) tangente 

m dup f point

gsave
newpath
   mixte
   m Ymin smoveto
   m Ymax slineto
stroke
grestore

medium setlinewidth
{f} courbe

setTimesItalic
   (O) 0 0 dltext
   (m) m 0 drtext