You don't give an example, but in general you can use a vector for cex with the values proportional to the third variable.
Same goes for color: col can be a vector, not just a single value. This has been discussed before on-list, and fairly recently. Sarah On Wed, Jan 12, 2011 at 2:19 PM, John Sorkin <jsor...@grecc.umaryland.edu> wrote: > I would like to plot 3-dimensional data on a two-dimensional scatter-plot. > Is there a way I can automatically modify the plot symbol (e.g. changing size > or color) to indicate the value of a third variable? E.g. How can I plot > weight vs. age and indicate the value of muscle mass for each value > weight-age pair by making the plot point proportional to the subject's muscle > mass? > Thanks, > John > -- Sarah Goslee http://www.functionaldiversity.org ______________________________________________ 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.
