50 setxunit 7.5 setborder 90 setangle_repere -2.1 2.1 setxrange -1.1 1.1 setyrange 1 1 settkstep .5 .5 setsubtkstep 2 2 setmkstep ticks subticks marks traceaxes axesarrow 0.75 setlinewidth continu bleu /X {settvar #rpn# (1+cos(t))*sin(2*t) } def /Y {settvar #rpn# cos(2*t) } def 0 200 pi mul {X} {Y} Courbeparam