我想知道是否有可能获得显示每个 X 值的 Data A 上方和 Data B 下方的双面条形图（例如 Two sided bar plot ordered by date）。
数据 A 可以是一个人的年龄，数据 B 是同一个人的大小。这个问题以及与上述示例的主要区别：A 和 B 显然具有完全不同的单位/ylims。
示例：
X = c("Anna","Manuel","Laura","Jeanne") # Name of the Person
A = c(12,18,22,10) # Age in years
B = c(112,186,165,120) # Size in cm
任何想法如何解决这个问题？我不介意水平或垂直解决方案。
非常感谢！
【问题讨论】：
这里的代码可以为您提供我认为您想要使用基础 R 中的 barplot 的可靠草稿。我只是将一个系列设为负数，然后手动设置 axis 中的标签以引用原始（正）值。您必须选择如何缩放这两个系列，这样比较仍然可以提供信息。我在这里通过将高度（以厘米为单位）除以 10 来做到这一点，这会产生与多年来的范围相似的范围。
# plot the first series, but manually set the range of the y-axis to set up the
# plotting of the other series. Set axes = FALSE so you can get the y-axis
# with labels you want in a later step.
barplot(A, ylim = c(-25, 25), axes = FALSE)
# plot the second series, making whatever transformations you need as you go. Use
# add = TRUE to add it to the first plot; use names.arg to get X as labels; and
# repeat axes = FALSE so you don't get an axis here, either.
barplot(-B/10, add = TRUE, names.arg = X, axes = FALSE)
# add a line for the x-axis if you want one
abline(h = 0)
# now add a y-axis with labels that makes sense. I set lwd = 0 so you just
# get the labels, no line.
axis(2, lwd = 0, tick = FALSE, at = seq(-20,20,5),
labels = c(rev(seq(0,200,50)), seq(5,20,5)), las = 2)
# now add y-axis labels
mtext("age (years)", 2, line = 3, at = 12.5)
mtext("height (cm)", 2, line = 3, at = -12.5)
par(mai = c(0.5, 1, 0.25, 0.25)) 的结果：
【讨论】：