[R] Order of boxes in boxplot()

[Jim Porzak]

On Thu, 7 Apr 2005, michael watson (IAH-C) wrote: 
> Sorry for such an inane question - how do I control the order in which 
> the boxes are plotted using boxplot() when I pass it a formula and a 
> data.frame? It seems that the groups are plotted in alphabetical 
> order... I want to change this.... 

Mick,
Here's the code I use to order boxes by decreasing median value. 
SubtDays is variable of interest
ConChnl is original grouping factor.
tMedians is a temp data frame 
dConChnl is new grouping factor with desired order


boxplot(SubtDays ~ ConChnl, .          ### Default ordering of boxes

tMedians <- aggregate(SubtDays, list(ConChnl), median, na.rm = TRUE)
dConChnl <- factor(ConChnl, levels = tMedians[order(tMedians$x), 1])

boxplot(SubtDays ~ dConChnl, .         ### Ordered by decreasing median


HTH,
Jim Porzak
Director of Analytics
Loyalty Matrix, Inc.
(415) 296-1141 x210
R.LoyaltyMatrix.com
www.LoyaltyMatrix.com