[R] barplot x axis labels

[Andrew Perrin]

I know this has got to be easy, but can't figure it out.

I've got a data frame that includes several numeric indices and a date for
each of 1100 records.  I'd like to plot a barplot of the mean of each of
these indices by date.  I've managed to do this:

> barplot(tapply(first.pro.auth.sum, dates(date), mean))

but even though I use the dates(date) function, the x axis displays
numeric labels, not dates. I'd like it to display the dates. Any advice?

Thanks.

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Andrew J Perrin - http://www.unc.edu/~aperrin
Assistant Professor of Sociology, U of North Carolina, Chapel Hill
clists at perrin.socsci.unc.edu * andrew_perrin (at) unc.edu