"plot.point.pairs" <-
function(x, data, xcol = data$x, ycol = data$y, xlab = "x coordinate",
ylab = "y coordinate", col.line = 2, line.pch = 0, ...) {
xyplot(ycol ~ xcol, aspect = mapasp(x = xcol, y = ycol),
panel = panel.point.pairs, xlab = xlab, ylab = ylab, pairs = x,
col.line = col.line, line.pch = line.pch, ...)
}