facet_wrap 布局类似于 facet_grid

Question

使用 facet_grid 根据提供的变量中的因子水平包装面板，即使给定组合没有数据。这就是我追求的行为。

不幸的是，y 轴刻度不能独立于单个面板级别（参见 here and here）。为此，您必须使用 facet_wrap.

然而，

facet_wrap 不提供与 facet_grid 相同的布局，并且仅显示具有要绘制的值的面板。

如何保持类似 facet_grid 的布局但具有独立的 y 轴刻度？没有数据的面板如果是blank/void也没关系，只要占据合适的space.

可重现的例子：

library(ggplot2)
set.seed(1)

# Generate data
test <- data.frame(x = c(rep(1, 6), rep(2, 6)), 
                   facet_1 = rep(c("A", "A", "A", "B", "B", "C"), 2),
                   facet_2 = rep(c("B", "C", "D", "C", "D", "D"), 2),
                   y = c(1e0, 1e1, 1e2, 1e3, 1e4, 1e5, rnorm(1, 1e0, 1e0*.34), rnorm(1, 1e1, 1e1*.34), rnorm(1, 1e2, 1e2*.34), rnorm(1, 1e3, 1e3*.34), rnorm(1, 1e4, 1e4*.34), rnorm(1, 1e5, 1e5*.34)))

# facet_grid - Shows blank panels B-B, B-C, and C-C. This is what I want.
#            - Does NOT scale y appropriately at the individual panel level.
ggplot(test, aes(x = x, y = y)) +
  facet_grid(facet_2 ~ facet_1, scales = "free") +
  geom_line()

# facet_wrap - Does NOT show blank panels B-B, B-C, and C-C.
#            - Does scale y appropriately at the individual panel level.
ggplot(test, aes(x = x, y = y)) +
  facet_wrap(vars(facet_1, facet_2), scales = "free") +
  geom_line()

Answer 1

你可以complete缺失的组合然后绘图。

library(ggplot2)

tidyr::complete(test, facet_1, facet_2, fill = list(x = 0, y = 0)) %>%
#Keeping them as NA would give a blank plot
#tidyr::complete(test, facet_1, facet_2) %>%
   ggplot() + aes(x = x, y = y) +
   facet_wrap(vars(facet_1, facet_2), scales = "free") +
   geom_line()

这会给你一个警告，因为这 3 个组中只有一个观察值。

facet_wrap 布局类似于 facet_grid

facet_wrap with layout like facet_grid

r

data-visualization

facet

ggplot2