60 setxunit
2.5 setborder
90 setangle_repere
-0.5 2.5 setxrange
-1.5 1.5 setyrange
1 1 settkstep
.5 .5 setsubtkstep
1 1 setmkstep
ticks
subticks
marks
traceaxes
axesarrow
/R {settvar
    1 t Cos add
} def
  0  2 pi mul settrange
gsave
   .75 setlinewidth
   continu
   noir
   (R) courbepolar
grestore