Facets的整体标签

Question

这是一些生成具有两组方面的图形的最小代码.

library("ggplot2", quietly = TRUE, warn.conflicts = FALSE)
library("RColorBrewer", quietly = TRUE, warn.conflicts = FALSE)
val.a <- rnorm(10)
val.b <- rnorm(10)
val.c <- c("A","B","A","A","B","B","B","B","A","B")
val.d <- c("D","D","E","D","E","E","E","D","D","E")
val.e <- rnorm(10)
maya <- data.frame(val.a,val.b,val.c,val.d,val.e)
ggplot(maya, aes(x=val.a, y=val.b)) +
  geom_point(shape=20,size=3, aes(colour=val.e)) +
  facet_grid(val.c~val.d) +
  xlab("Leonardo") + ylab("Michaelangelo") +
  scale_colour_gradientn(colours=brewer.pal(9,"YlGnBu"), name="Splinter")

我无法弄清楚如何添加整个构面标签,以便名称Donatello和Raphael位于顶部和右侧轴上.

我在SO上看到了一些类似的解决方案,但我无法对代码进行反复无常的研究.请问你能否解答我的难题？

类似的问题在这里,但如果我有两个以上的方面,它就失败了.标签显示在图表内的某处.有没有办法让这个工作适用于一般情况？

所以我在上面的链接上尝试了rawr的解决方案,最终在多个列的同一个地方.这是更新为rawr解决方案的代码,但是它产生了意外的标签(对我来说因为我不理解解决方案).

library("ggplot2", quietly = TRUE, warn.conflicts = FALSE)
library("RColorBrewer", quietly = TRUE, warn.conflicts = FALSE)
val.a <- rnorm(20)
val.b <- rnorm(20)
val.c <- c("A","B","C","D","E","F","G","H","I","J")
val.d <- c("A","B","C","D","E","F","G","H","I","J")
val.e <- rnorm(20)
maya <- data.frame(val.a,val.b,val.c,val.d,val.e)
p <- ggplot(maya, aes(x=val.a, y=val.b)) + geom_point(shape=20,size=3, aes(colour=val.e)) + facet_grid(val.c~val.d) + xlab("Leonardo") + ylab("Michaelangelo") + scale_colour_gradientn(colours=brewer.pal(9,"YlGnBu"), name="Splinter")
z <- ggplotGrob(p)

library(grid)
library(gtable)
# add label for right strip
z <- gtable_add_cols(z, unit(z$width[[7]], 'cm'), 7)
z <- gtable_add_grob(z, 
                     list(rectGrob(gp = gpar(col = NA, fill = gray(0.5))),
                          textGrob("Variable 1", rot = -90, gp = gpar(col = gray(1)))),
                     4, 8, 6, name = paste(runif(2)))

# add label for top strip
z <- gtable_add_rows(z, unit(z$heights[[3]], 'cm'), 2)
z <- gtable_add_grob(z, 
                     list(rectGrob(gp = gpar(col = NA, fill = gray(0.5))),
                          textGrob("Variable 2", gp = gpar(col = gray(1)))),
                     3, 4, 3, 6, name = paste(runif(2)))

# add margins
z <- gtable_add_cols(z, unit(1/8, "line"), 7)
z <- gtable_add_rows(z, unit(1/8, "line"), 3)

# draw it
grid.newpage()
grid.draw(z)

请有人向我指出代码的一部分,告诉它一般方面标签应该有多宽？

Answer 1

这很普遍.顶部和右侧条带的当前位置在布局数据框中给出.此解决方案使用这些位置来定位新条带.新条带的构造使高度,宽度,背景颜色,字体大小和颜色与当前条带相同.下面有一些解释.

# Packages
library(ggplot2)
library(RColorBrewer)
library(grid)
library(gtable)

# Data
val.a <- rnorm(20)
val.b <- rnorm(20)
val.c <- c("A","B","C","D","E","F","G","H","I","J")
val.d <- c("A","B","C","D","E","F","G","H","I","J")
val.e <- rnorm(20)
maya <- data.frame(val.a,val.b,val.c,val.d,val.e)

# Base plot
p <- ggplot(maya, aes(x = val.a, y = val.b)) + 
   geom_point(shape = 20,size = 3, aes(colour = val.e)) + 
   facet_grid(val.c ~ val.d) + 
   xlab("Leonardo") + ylab("Michaelangelo") + 
   scale_colour_gradientn(colours = brewer.pal(9,"YlGnBu"), name = "Splinter")

# Labels 
labelR = "Variable 1"
labelT = "Varibale 2"

# Get the ggplot grob
z <- ggplotGrob(p)

# Get the positions of the strips in the gtable: t = top, l = left, ...
posR <- subset(z$layout, grepl("strip-r", name), select = t:r)
posT <- subset(z$layout, grepl("strip-t", name), select = t:r)

# Add a new column to the right of current right strips, 
# and a new row on top of current top strips
width <- z$widths[max(posR$r)]    # width of current right strips
height <- z$heights[min(posT$t)]  # height of current top strips

z <- gtable_add_cols(z, width, max(posR$r))  
z <- gtable_add_rows(z, height, min(posT$t)-1)

# Construct the new strip grobs
stripR <- gTree(name = "Strip_right", children = gList(
   rectGrob(gp = gpar(col = NA, fill = "grey85")),
   textGrob(labelR, rot = -90, gp = gpar(fontsize = 8.8, col = "grey10"))))

stripT <- gTree(name = "Strip_top", children = gList(
   rectGrob(gp = gpar(col = NA, fill = "grey85")),
   textGrob(labelT, gp = gpar(fontsize = 8.8, col = "grey10"))))

# Position the grobs in the gtable
z <- gtable_add_grob(z, stripR, t = min(posR$t)+1, l = max(posR$r) + 1, b = max(posR$b)+1, name = "strip-right")
z <- gtable_add_grob(z, stripT, t = min(posT$t), l = min(posT$l), r = max(posT$r), name = "strip-top")

# Add small gaps between strips
z <- gtable_add_cols(z, unit(1/5, "line"), max(posR$r))
z <- gtable_add_rows(z, unit(1/5, "line"), min(posT$t))

# Draw it
grid.newpage()
grid.draw(z)