Hi Christophe,
just try :
legend("top",leg=c("a","b"),fill=c("black","blue"))
instead of your :
legend("top",leg=c("a","b"),col=c("black","blue"), fill=TRUE)
Regards, Olivier
Olivier ETERRADOSSI Ma?tre-Assistant CMGD / Equipe "Propri?t?s Psycho-Sensorielles des Mat?riaux" Ecole des Mines d'Al?s H?lioparc, 2 av. P. Angot, F-64053 PAU CEDEX 9 tel std: +33 (0)5.59.30.54.25 tel direct: +33 (0)5.59.30.90.35 fax: +33 (0)5.59.30.63.68 http://www.ema.fr