[R] Sorting problem

[Gabor Grothendieck]

> From:   <Ted.Harding at nessie.mcc.ac.uk>
>  
> On 24-Dec-04 Gabor Grothendieck wrote:
> > 
> > From: Paul JH Drake <p.drake at beatson.gla.ac.uk>
> >> 
> >> When I plot data as a boxplot, the boxes appear on the plot in
> >> alphabetical order (of group) rather than the order in which they
> >> appear
> >> in the data. So far, the only thing I can do to fix this is to prefix
> >> the group labels with a,b,c...etc to trick R into plotting them in the
> >> right order.
> >> 
> >> Can sorting be turned off?
> >> How should I address this sensibly?
> > 
> > Actually they are shown in order of the levels of the factor.
> > e.g. to show them in reverse order:
> > 
> > attach(InsectSprays)
> > spray <- factor( as.character(spray), level = rev(levels(spray)) )
> > boxplot(count ~ spray)
> 
> Applying boxplot to data constructed as follows:
> 
> X<-list(C=rnorm(10),B=rnorm(20),A=rnorm(30))
> boxplot(X)
> 
> gives the plots in the order "C", "B", "A", so here they indeed
> come out in the order of the data.
> 
> But suppose I had wanted them in the order "B", "A", "C", say.
> How would Gabor's suggestion (or similar) be applied to this case?

boxplot(X[c("B","C","A")])