Hio i tried to do this by: par(new=TRUE) but the result is one picture but y-axis has 2 différent graduations.how can i correct this?( i want one graduation on y axis). -- View this message in context: http://www.nabble.com/how-can-i-superpose-2--graphs-tp17305355p17305355.html Sent from the R help mailing list archive at Nabble.com.