随机生成点的大小、颜色和位置，分别用空心点和实心点画图。

par(mar = c(0.2, 0.2, 0.2, 0.2), mfrow = c(2, 2))
for (n in c(63, 60, 76, 74)) {
set.seed(77)
plot.new()
size = c(replicate(n, 1/rbeta(2, 1.5, 4)))
center = t(replicate(n, runif(2)))
center = center[rep(1:n, each = 2), ]
color = apply(replicate(2 * n, sample(c(0:9,
LETTERS[1:6]), 8, TRUE)), 2, function(x) sprintf("#%s",
paste(x, collapse = "")))
points(center, cex = size, pch = rep(20:21, n),
col = color)
box()
}

效果图