[R] Wrapping long labels in barplot(2)

[Jan P. Smit]

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.

Jan Smit

Consultant
Economic and Social Commission for Asia and the Pacific