ggplot2 上多面直方图中的各个 binwidth

Question

我制作了一系列直方图，并且facet_grid希望网格中的每个直方图都具有相同数量的类，在下面的示例中，例如 6 个类。下面这个例子中的问题是binwidth = diff(range(x$data))/6)根据a、b和c的整体范围来定义类，即为所有三个方面定义一个binwidth。

如何分别定义面 a、b 和 c 的 binwidth？

require("ggplot2")

a <- c(1.21,1.57,1.21,0.29,0.36,0.29,0.93,0.26,0.28,0.48,
       0.12,0.38,0.83,0.82,0.41,0.69,0.25,0.98,0.52,0.11)
b <- c(0.42,0.65,0.17,0.38,0.44,0.01,0.01,0.03,0.15,0.01)
c <- c(1.09,3.55,1.07,4.55,0.55,0.11,0.72,0.66,1.22,3.04,
       2.01,0.64,0.47,1.33,3.44)

x <- data.frame(data = c(a,b,c), variable = c(rep("a",20),rep("b",10),rep("c",15)),area="random")

qplot(data, data = x, geom = "histogram", binwidth = diff(range(x$data))/6) +
  facet_grid(area~variable, scales = "free")

Answer 1

这不是最佳选择，但您可以在不同层中绘制直方图：

ggplot(x, aes(x=data)) +
   geom_histogram(data=subset(x, variable=="a"), binwidth=.1) +
   geom_histogram(data=subset(x, variable=="b"), binwidth=.2) +
   geom_histogram(data=subset(x, variable=="c"), binwidth=.5) +
   facet_grid(area~variable, scales="free")