ggsave losing unicode characters from ggplot+gridExtra

Question

More code than you really need, but to set the mood:

#Make some data and load packages
data<-data.frame(pchange=runif(80,0,1),group=factor(sample(c(1,2,3),80,replace=T)))
library(dplyr)
library(magrittr)
library(gridExtra)
library(ggplot2)
data%<>%arrange(group,pchange) %>% mutate(num=1:80)

#Make plot that includes unicode characters
g1<-ggplot(data, aes(factor(num),pchange, fill = group,width=.4)) +
  geom_bar(stat="identity", position = "dodge") +
  theme_classic()+
  theme(axis.ticks = element_blank(), 
        axis.text.x = element_blank(),
        legend.position="right")+
  scale_y_continuous(breaks=c(0,.25,.5,.75,1))+
  xlab("")+
  scale_fill_discrete("Arbitrary Group",
                      breaks=c(1,2,3),
                      labels=c("< 1 Year", "\u2265 1 Year & \n\u2264 5 Years","> 5 Years"))


#I want to add an A below the plot (this may not be necessary for the issue, but its a part of the workflow so I thought I'd include it.
g <- arrangeGrob(plot=g1,
                 sub = textGrob("A",
                                x = .1,
                                hjust = .5,
                                vjust=-2,
                                gp = gpar(fontface = "bold",
                                          fontsize = 16,
                                          col="black")))

#Save the plot
ggsave(filename="X:/yourpath/Plot1.pdf", plot=g,
       width = 8, height = 4, units = "in", dpi = 600)

Here's what it looks like:

Here's what it should look like (in terms of the characters in the key; plot taken as jpeg directly from Rstudio plot window):

Answer 1

You have two options. One, use the cairo_pdf device instead of the default pdf in your call you ggsave, e.g.,

library(Cairo)
ggsave(filename="X:/yourpath/Plot1.pdf", plot=g, device=cairo_pdf,
       width = 8, height = 4, units = "in", dpi = 600)

The other option would be to use expressions instead of explicit unicode characters:

g<-ggplot(data, aes(factor(num),pchange, fill = group,width=.4)) +
  geom_bar(stat="identity", position = "dodge") +
  theme_classic()+
  theme(axis.ticks = element_blank(), 
        axis.text.x = element_blank(),
        legend.position="right")+
  scale_y_continuous(breaks=c(0,.25,.5,.75,1))+
  xlab("")+
  scale_fill_discrete("Arbitrary Group",
                      breaks=c(1,2,3),
                      labels=c(expression(phantom(0) < "1 Year"), 
                              expression(paste(phantom(0) >= "1 Year &", phantom(0) <= "5 Years")),
                              expression(phantom(0) > "5 Years")))



ggsave(filename="Plot1.pdf", plot=g,
       width = 8, height = 4, units = "in", dpi = 600)

Although, as you can see, with the second option the formatting isn't as tight as you might like.

As to why you are experiencing this issue, according to the answer here, the pdf driver can only handle single byte encodings.