Profs. Ripley and Schwartz, Thank you both very much for the suggestions! These are exactly what I was looking for. I'll re-read the boxplot help yet again; every time I read it something essential worms its way into my consciousness, but it enters more freely when I have a hint where to look. The sad truth is that I was heading for a ~10-line hacker solution. You've saved me from my usual code-writing ignomy.
Happy new year, -Joseph Prof Brian Ripley wrote: > On Thu, 5 Jan 2006, Marc Schwartz wrote: > >> On Thu, 2006-01-05 at 20:27 -0600, Joseph LeBouton wrote: >> >>> Hi all, >>> >>> what a great help list! I hope someone can help me with this puzzle... >>> >>> I'm trying to find a simple way to do: >>> >>> boxplot(obs~factor) >>> >>> so that the factors are ordered left-to-right along the x-axis by >>> median, not alphabetically by factor name. > > > The thing to realize is that they are not alphabetic, but ordered by > factor levels. So the key is to set the levels. (The help page for > boxplot does say that, as I was relieved to find.) > >>> Complicated ways abound, but I'm hoping for a magical one-liner that'll >>> do the trick. >>> >>> Any suggestions would be treasured. >>> >>> Thanks, >>> >>> -jlb >> >> >> >> Using the first example in ?boxplot, which is: >> >> boxplot(count ~ spray, data = InsectSprays, col = "lightgray") >> >> >> >> Get the medians for 'count by spray' using tapply() and then sort the >> results in increasing order, by median: >> >> med <- sort(with(InsectSprays, tapply(count, spray, median))) >> >>> med >> >> C E D A F B >> 1.5 3.0 5.0 14.0 15.0 16.5 >> >> >> Now do the boxplot, setting the factor levels in order by median: >> >> boxplot(count ~ factor(spray, levels = names(med)), >> data = InsectSprays, col = "lightgray") >> >> >> So...technically two lines of code. > > > This was answered yesterday in terms of bwplot. See ?reorder.factor > for the same example done using reorder.factor. That will give you the > single line asked for, and be self-explanatory. > -- ************************************ Joseph P. LeBouton Forest Ecology PhD Candidate Department of Forestry Michigan State University East Lansing, Michigan 48824 Office phone: 517-355-7744 email: [EMAIL PROTECTED] ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html