Thank you every body for your suggestion. It does help. On Fri, Apr 6, 2012 at 2:37 AM, windmagics_lsl <shfu_...@163.com> wrote:
> I think there may 3 legends should be added in your plot > the argument col, pch and pt.cex should be in the same length with legend, > but the objects col, pch > and cex you defined former have 16*3 length. I guess the follow codes may > work > > col <- rep(c("blue", "red", "darkgreen"), c(16, 16, 16)) > ## Choose different size of points > cex <- rep(c(1, 1.2, 1), c(16, 16, 16)) > ## Choose the form of the points (square, circle, triangle and > diamond-shaped > pch <- rep(c(15, 16, 17), c(16, 16, 16)) > > plot(axis1, axis2, main="My plot", xlab="Axis 1", ylab="Axis 2", > col=c(Category, col), pch=pch, cex=cex) > legend(4, 12.5, c("NorthAmerica", "SouthAmerica", "Asia"), col = > unique(col), > pch = unique(pch), pt.cex = unique(cex), title = "Region") > > -- > View this message in context: > http://r.789695.n4.nabble.com/Legend-based-on-levels-of-a-variable-tp4536796p4536868.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. > -- Section of Integrative Biology University of Texas at Austin Austin, Texas 78712, USA [[alternative HTML version deleted]] ______________________________________________ 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.