I have a multiplot figure consisting of 4 plots in a 2x2 configuration. I arranged the plots using the "cowplot" package and the plot_grid function using the code below
plot_grid(p1, p2, p3, p4, align='vh', vjust=1, scale = 1)
where p1-p4 are my 4 plots. The resulting figure has an x-axis label associated with each column in the multiplot:
Does anyone know how I can code a single x-axis label centered at the bottom of the multiplot, either with cowplot or another way?
Another option is to use textGrob
to add annotations for common x and y labels.
In this example, if you wish to remove the individual axis labels, just include theme(axis.title = element_blank())
in the plot calls. (or, for just y-axis, use theme(axis.title.y=element_blank())
).
library(ggplot2)
library(cowplot)
library(grid)
library(gridExtra)
ToothGrowth$dose <- as.factor(ToothGrowth$dose)
#make 4 plots
p1<-ggplot(ToothGrowth, aes(x=dose, y=len)) +
geom_boxplot()
p2<-ggplot(ToothGrowth, aes(x=dose, y=supp)) +
geom_boxplot()
p3<-ggplot(ToothGrowth, aes(x=supp, y=len)) +
geom_boxplot()
p4<-ggplot(ToothGrowth, aes(x=supp, y=dose)) +
geom_boxplot()
#combine using cowplot
plot<-plot_grid(p1, p2, p3, p4, align='vh', vjust=1, scale = 1)
#create common x and y labels
y.grob <- textGrob("Common Y",
gp=gpar(fontface="bold", col="blue", fontsize=15), rot=90)
x.grob <- textGrob("Common X",
gp=gpar(fontface="bold", col="blue", fontsize=15))
#add to plot
grid.arrange(arrangeGrob(plot, left = y.grob, bottom = x.grob))