Changing the aesthetics of a nested face in ggplot2

Question

I want to use nested panels in ggplot2 , but the names of the two panels should be on different sides of the graph. Here is an example of reproducibility:

 library(ggplot2) library(data.table) # data for reproducible example dt <- data.table( value = c("East", "West","East", "West", "NY", "LA","NY", "LA"), year = c(2008, 2008, 2013, 2013, 2008, 2008, 2013, 2013), index = c(12, 10, 18, 15, 10, 8, 12 , 14), var = c("Region","Region","Region","Region", "Metro","Metro","Metro","Metro")) # change order or plot facets dt[, var := factor(var, levels=c( "Region", "Metro"))] # plot ggplot(data=dt) + geom_point( aes(x=index, y= factor(year), color=index)) + facet_grid(value + var ~., scales = "free_y", space="free") 

Note that in this example, I use the value + var columns to create faces, but the title of the two panels is displayed together.

Expected Result . What I would like to receive is the following:

Answer 1

Possible solution using labeller = label_bquote(rows = .(var1)) , two calls to geom_text and some additional settings:

 ggplot(dt, aes(x = index, y = factor(year), color = index)) + geom_point() + geom_text(aes(x = 6, y = 1.5, label = value), color = 'black', hjust = 0) + geom_text(aes(x = 7, label = year), color = 'black') + geom_segment(aes(x = 7.5, xend = 7.5, y = 0.7, yend = 2.3), color = 'black') + geom_segment(aes(x = 7.45, xend = 7.5, y = 1, yend = 1), color = 'black') + geom_segment(aes(x = 7.45, xend = 7.5, y = 2, yend = 2), color = 'black') + scale_x_continuous(breaks = seq(8,18,2)) + facet_grid(value + var1 ~., scales = "free_y", space="free", labeller = label_bquote(rows = .(var1))) + theme_minimal() + theme(axis.title = element_blank(), axis.text.y = element_blank(), strip.background = element_rect(color = 'darkgrey', fill = 'lightgrey'), panel.grid.major.y = element_blank(), panel.grid.minor = element_blank()) 

which gives:

Note. I used var1 instead of var because the latter is also the name of the function.

---

Another possibility is to use the gridExtra package to create additional labels and place them in front of the y axis labels using grid.arrange :

 # create the main plot mainplot <- ggplot(dt, aes(x = index, y = factor(year), color = index)) + geom_point(size = 2) + scale_x_continuous(breaks = seq(8,18,2)) + facet_grid(value + var1 ~., scales = "free_y", space="free", labeller = label_bquote(rows = .(var1))) + theme_minimal() + theme(axis.title = element_blank(), strip.background = element_rect(color = 'darkgrey', fill = 'lightgrey')) # create a 2nd plot with everything besides the labels set to blank or NA lbls <- ggplot(dt, aes(x = 0, y = factor(year))) + geom_point(color = NA) + geom_text(aes(x = 0, y = 1.5, label = value), color = 'black') + scale_x_continuous(limits = c(0,0), breaks = 0) + facet_grid(value + var1 ~.) + theme_minimal() + theme(axis.title = element_blank(), axis.text.x = element_text(color = NA), axis.text.y = element_blank(), strip.background = element_blank(), strip.text = element_blank(), panel.grid = element_blank(), legend.position = 'none') # plot with 'grid.arrange' and give the 'lbls'-plot a small width library(gridExtra) grid.arrange(lbls, mainplot, ncol = 2, widths = c(1,9)) 

which gives:

Answer 2

Adding this mainly to show some game manipulation / gtable:

 library(ggplot2) library(data.table) library(gtable) library(gridExtra) # data for reproducible example dt <- data.table( value = c("East", "West","East", "West", "NY", "LA","NY", "LA"), year = c(2008, 2008, 2013, 2013, 2008, 2008, 2013, 2013), index = c(12, 10, 18, 15, 10, 8, 12 , 14), var = c("Region","Region","Region","Region", "Metro","Metro","Metro","Metro")) # change order or plot facets dt[, var := factor(var, levels=c( "Region", "Metro"))] # plot ggplot(data=dt) + geom_point( aes(x=index, y= factor(year), color=index)) + facet_grid(value + var ~., scales = "free_y", space="free") + theme_bw() + theme(panel.grid=element_blank()) + theme(panel.border=element_blank()) + theme(axis.line.x=element_line()) + theme(axis.line.y=element_line()) -> gg gb <- ggplot_build(gg) gt <- ggplot_gtable(gb) 

Here's what it looks like:

 gt ## TableGrob (14 x 8) "layout": 24 grobs ## z cells name grob ## 1 0 ( 1-14, 1- 8) background rect[plot.background..rect.5201] ## 2 5 ( 4- 4, 3- 3) axis-l absoluteGrob[GRID.absoluteGrob.5074] ## 3 6 ( 6- 6, 3- 3) axis-l absoluteGrob[GRID.absoluteGrob.5082] ## 4 7 ( 8- 8, 3- 3) axis-l absoluteGrob[GRID.absoluteGrob.5090] ## 5 8 (10-10, 3- 3) axis-l absoluteGrob[GRID.absoluteGrob.5098] ## 6 1 ( 4- 4, 4- 4) panel gTree[GRID.gTree.5155] ## 7 2 ( 6- 6, 4- 4) panel gTree[GRID.gTree.5164] ## 8 3 ( 8- 8, 4- 4) panel gTree[GRID.gTree.5173] ## 9 4 (10-10, 4- 4) panel gTree[GRID.gTree.5182] ## 10 9 ( 4- 4, 5- 5) strip-right absoluteGrob[strip.absoluteGrob.5104] ## 11 10 ( 6- 6, 5- 5) strip-right absoluteGrob[strip.absoluteGrob.5110] ## 12 11 ( 8- 8, 5- 5) strip-right absoluteGrob[strip.absoluteGrob.5116] ## 13 12 (10-10, 5- 5) strip-right absoluteGrob[strip.absoluteGrob.5122] ## 14 13 ( 4- 4, 6- 6) strip-right absoluteGrob[strip.absoluteGrob.5128] ## 15 14 ( 6- 6, 6- 6) strip-right absoluteGrob[strip.absoluteGrob.5134] ## 16 15 ( 8- 8, 6- 6) strip-right absoluteGrob[strip.absoluteGrob.5140] ## 17 16 (10-10, 6- 6) strip-right absoluteGrob[strip.absoluteGrob.5146] ## 18 17 (11-11, 4- 4) axis-b absoluteGrob[GRID.absoluteGrob.5066] ## 19 18 (12-12, 4- 4) xlab titleGrob[axis.title.x..titleGrob.5185] ## 20 19 ( 4-10, 2- 2) ylab titleGrob[axis.title.y..titleGrob.5188] ## 21 20 ( 4-10, 7- 7) guide-box gtable[guide-box] ## 22 21 ( 3- 3, 4- 4) subtitle zeroGrob[plot.subtitle..zeroGrob.5198] ## 23 22 ( 2- 2, 4- 4) title zeroGrob[plot.title..zeroGrob.5197] ## 24 23 (13-13, 4- 4) caption zeroGrob[plot.caption..zeroGrob.5199] 

We can easily manipulate these components:

 # make a copy of the gtable (not rly necessary but I think it helps simplify things since # I'll usually forget to offset the column positions at some point if the # manipulations get too involved) gt2 <- gt # add a new column after the axis title gt2 <- gtable_add_cols(gt2, unit(3.0, "lines"), 2) # these are those pesky strips of yours for_left <- gt[c(4,6,8,10),5] # let copy them over into our new column gt2 <- gtable_add_grob(gt2, for_left$grobs[[1]], t=4, l=3, b=4, r=3) gt2 <- gtable_add_grob(gt2, for_left$grobs[[2]], t=6, l=3, b=6, r=3) gt2 <- gtable_add_grob(gt2, for_left$grobs[[3]], t=8, l=3, b=8, r=3) gt2 <- gtable_add_grob(gt2, for_left$grobs[[4]], t=10, l=3, b=10, r=3) # then get rid of the original ones gt2 <- gt2[, -6] # now we'll change the background color, border color and text rotation of each strip text for (gi in 21:24) { gt2$grobs[[gi]]$children[[1]]$gp$fill <- "white" gt2$grobs[[gi]]$children[[1]]$gp$col <- "white" gt2$grobs[[gi]]$children[[2]]$children[[1]]$rot <- 0 } grid.arrange(gt2) 

The IMO user approach of labeller and geom_text in the first answer is much more readable and repeatable.