Hi Mamum, The co-ordinates appear shifted because the bars are not centered at 1, 2, 3, etc. To give an example:
# Create a barplot # of the numbers 1 through 10 barplot(1:10) # Now look at the x axis coordinates of these actual bars barplot(1:10, plot = FALSE) # One way to get these coordinates for yourself would be x <- barplot(1:10) # this will plot AND save the object x # see the coordinates # This should have the points properly centered with the bars points(x = x, y = 10:1) HTH, Josh On Wed, Sep 8, 2010 at 6:14 AM, mamunbabu2001 <mrashi...@hotmail.com> wrote: > > Hi Peng, > Thanks for your reply. I have tried it and it does work fine > apart from one problem. Even though the second data set > has same length as the first one, the point function seems > to shit all the points towards left side. So the points are not > in concordat co-ordinates as the bars. Any idea how this can > be fixed ??? > > thanks in advace. > > regards, > Mamun > -- > View this message in context: > http://r.789695.n4.nabble.com/Over-lay-2-scale-in-same-plot-tp2528661p2531255.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles http://www.joshuawiley.com/ ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.