R users,
I am creating a series of scatterplots with Lattice's xyplot(). Some of the plotting symbols are squares with thick borders. The corners of the squares are rounded by default; I would like them to be square. In base graphics this is easily done with par(ljoin = "mitre"), and in grid graphics with gpar(linejoin = "mitre"). Is there an analogous parameter in Lattice? Passing ljoin as an argument to xyplot() or panel functions doesn't seem to work, and I can't find anything promising in lattice.par.get().
Thanks,
Andrew Morgan
Department of Genetics
University of North Carolina - Chapel Hill