在不同的axis.title/text属性的情况下调整面板图（ggplot）子图之间的间距

Question

I would like to adjust the spacing between plots that are aligned in a panel using the cowplot package when some plots contain axis titles/labels, and others don't.

Example

Let's create three plots:

library(tidyverse)
library(cowplot)

set.seed(123)

df <- data.frame(x = rnorm(n = 100), 
                 y = rnorm(n = 100))

plot <- ggplot(data = df, aes(x, y)) + geom_point()

plot_grid(plot, plot, plot, nrow = 1, align = "vh") 

These plots are aligned perfectly, But often. I have a scenario in which I would like to create a 'cleaner' panel figure. One way to do this is to remove the titles/text of the y-axis of the second and third plots.

Like this:

plot2 <- plot + theme(axis.title.y = element_blank(),  
                      axis.text.y = element_blank())

plot_grid(plot, plot2, plot2, nrow = 1, align = "vh")

Again, perfectly aligned, but the spacing between the first and the second plot (and the second and third plot) is quite large. I would like to reduce the spacing to create a more compact plot, while the axis remain exactly the same size.

Expected output

Is this possible with cowplot ? Or is there another way to do this?

Answer 1

Referencing this post on github , plot_grid() doesn't add any space by default and uses the margins of your plot. To remove the space outside your plot area, you can use them(plot.margin=...) to remove.

With that being said... that's not what's going on here! Printing either plot or plot2 will yield a plot with no margins. It appears the issue is with the use of the align= argument in plot_grid() . I'm not sure why, but setting it to anything other than the default values ( align="none" ) results in the extra whitespace around the plots. Very strange... needless to say, removing that argument fixes your problem:

Original code using align="vh"

plot_grid(plot, plot2, plot2, nrow = 1, align="vh")

Using align="none"

plot_grid(plot, plot2, plot2, nrow = 1, align="none")

Any further space would be added according to your graphics device, since the actual plot you get depends on the size and resolution of that device.

Answer 2

Here is a solution using the patchwork package

library(tidyverse)

set.seed(123)

df <- data.frame(x = rnorm(n = 100), 
                 y = rnorm(n = 100))

plot1 <- ggplot(data = df, aes(x, y)) + geom_point()

plot2 <- plot1 + theme(axis.title.y = element_blank(),  
                      axis.text.y = element_blank())

# install.packages("patchwork", dependencies = TRUE)
library(patchwork)

plot1 + plot2 + plot2 +
  plot_layout(ncol = 3) 

^{Created on 2020-07-24 by the reprex package (v0.3.0)}