qqmath to reduce the number of points
plotted by sampling along the specified distribution. The usual method
for such sampling is to use the f.value argument to
panel.qqmath. However, this panel function differs in
two ways:
(1) a specified number of data points are retained (not
interpolated) on each tail of the distribution.
(2) the sampling is evenly spaced along the specified
distribution automatically (whereas f.value = ppoints(100) is
evenly spaced along the uniform distribution only).
This function is deprecated as of tails.n argument of
panel.qqmath instead.panel.qqmath.tails(x, f.value = NULL, distribution = qnorm,
groups = NULL, ..., approx.n = 100, tails.n = 10)panel.qqmath.panel.xyplot.panel.qqmath which should be used instead (as of