[R] Wrapping long labels in barplot(2)

[Jim Lemon]

Jan P. Smit wrote:
> I am using barplot, and barplot2 in the gregmisc bundle, in the 
> following way:
> 
> barplot2(sort(xtabs(expend / 1000 ~ theme)),
>     col = c(mdg7, mdg8, mdg3, mdg1), horiz = T, las = 1,
>     xlab = "$ '000", plot.grid = T)
> 
> The problem is that the values of 'theme', which is a factor, are in 
> some cases rather long, so that I would like to wrap/split them at a 
> space once they exceed, say, 20 characters. What I'm doing now is 
> specifying names.arg manually with '\n' where I want the breaks, but I 
> would like to automate the process.
> 
> I've looked for a solution using 'strwrap', but am not sure how to apply 
> it in this situation.
> 
You may find the staxlab function in the plotrix package to be helpful. 
It STaggers AXis LABels to allow fairly long strings to be displayed 
without overlapping.

Jim