Fonts

Problem
Solution

Problem

You want to use different fonts in your graphs.

Solution

Update: Also see the extrafont package for much better support of fonts for PDF and Windows bitmap output.

Font support in R is generally not very good. It varies between systems, and between output formats.

geom_text

With geom_text or annotate in ggplot2, you can set a number of properties of the text. geom_text is used to add text from the data frame, and annotate is used to add a single text element.

Name	Default value
`size`	5
`family`	`""` (sans)
`fontface`	`plain`
`lineheight`	1.2
`angle`	0
`hjust`	0.5
`vjust`	0.5

Note that size is in mm, not points.

dat <- data.frame(
    y = 1:3,
    text = c("This is text", "Text with\nmultiple lines", "Some more text")
)

library(ggplot2)
p <- ggplot(dat, aes(x=1, y=y)) + 
       scale_y_continuous(limits=c(0.5, 3.5), breaks=NULL) +
       scale_x_continuous(breaks=NULL)

p + geom_text(aes(label=text))

p + geom_text(aes(label=text), family="Times", fontface="italic", lineheight=.8) +
    annotate(geom="text", x=1, y=1.5, label="Annotation text", colour="red",
             size=7, family="Courier", fontface="bold", angle=30)

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themes and element_text

When controlling elements such as the title, legend, axis labels, and so on, you use element_text, which has the same parameters, except that size is points (not mm), and instead of fontface, it uses face. The default value of size depends on the element; for example, titles are larger than tick labels.

p + geom_point() +
    ggtitle("This is a Title") +
    theme(plot.title=element_text(family="Times", face="bold", size=20))

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Table of fonts

You can use this code to generate a graphical table of fonts. Fonts have short names and canonical family names. You can use either one when specifying the family.

fonttable <- read.table(header=TRUE, sep=",", stringsAsFactors=FALSE,
                        text='
Short,Canonical
mono,Courier
sans,Helvetica
serif,Times
,AvantGarde
,Bookman
,Helvetica-Narrow
,NewCenturySchoolbook
,Palatino
,URWGothic
,URWBookman
,NimbusMon
URWHelvetica,NimbusSan
,NimbusSanCond
,CenturySch
,URWPalladio
URWTimes,NimbusRom
')

fonttable$pos <- 1:nrow(fonttable)

library(reshape2)
fonttable <- melt(fonttable, id.vars="pos", measure.vars=c("Short","Canonical"),
                  variable.name="NameType", value.name="Font")

# Make a table of faces. Make sure factors are ordered correctly
facetable <- data.frame(Face = factor(c("plain","bold","italic","bold.italic"),
                                      levels = c("plain","bold","italic","bold.italic")))

fullfonts <- merge(fonttable, facetable)


library(ggplot2)
pf <- ggplot(fullfonts, aes(x=NameType, y=pos)) + 
             geom_text(aes(label=Font, family=Font, fontface=Face)) +
             facet_wrap(~ Face, ncol=2)

To view it on screen:

pf

What you see on the screen isn’t necessarily the same as what you get when you output to PNG or PDF. To see PNG output:

png('fonttable.png', width=720, height=720, res=72)
print(pf)
dev.off()

Notice that on the system that generated this picture, most of the fonts (at the top) don’t really work. Only the basic fonts (at the bottom) work.

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And PDF output (the image below has been converted from PDF to PNG):

pdf('fonttable.pdf', width=10, height=10)
print(pf)
dev.off()

# Convert to PNG using GraphicsMagick:
# system("gm convert -resize 720x720 -background white fonttable.pdf fonttable-pdf.png")

The PDF device has better font support than the PNG device. All the fonts work (though they’re not necessarily pretty):

PDF font table, converted to PNG