R:网格布局标题

Question

我正在使用 grid 包来显示这样的图数组:

layout <- grid.layout(2, 4)
pushViewport(viewport(layout = layout))
# print various plots

有没有办法为整个网格布局指定标题？

Answer 1

基于类似 SO 问题的虚拟示例:Place title of multiplot panel with ggplot2

首先创建一个具有所需行数 + 1 个短行作为标题的布局:

pushViewport(viewport(layout = grid.layout(3, 2, heights = unit(c(0.5, 5, 5), "null"))))   

在那里创建一些图:

print(ggplot(mtcars, aes(hp)) + geom_histogram(), vp = viewport(layout.pos.row = 2, layout.pos.col = 1:2))
print(ggplot(mtcars, aes(wt)) + geom_histogram(), vp = viewport(layout.pos.row = 3, layout.pos.col = 1))
print(ggplot(mtcars, aes(mpg)) + geom_histogram(), vp = viewport(layout.pos.row = 3, layout.pos.col = 2))

将标题添加到顶行:

grid.text("MAIN TITLE", vp = viewport(layout.pos.row = 1, layout.pos.col = 1:2))

导致: