How to place +/- plus minus operator in text annotation of plot (ggplot2)?

Question

I have tried the following, but it doesn't work for me:

a <- ggplot()
a <- a + geom_point(aes(x=seq(0,1,0.1), y=seq(0,1,0.1)))
a <- a + annotate("text", x=0.5, y=0.3, label="myplot")
a <- a + annotate("text", x=0.5,y=0.2,label=expression(%+-%))

I have also tried the following as pointed out by How to annotate() ggplot with latex with no luck:

a <- a + annotate("text", x=0.5, y=0.1, label="%+-%", parse=TRUE)

And this doesn't work either:

a <- a + annotate("text", x=0.5, y=0.1, label="\pm", parse=TRUE)

Jota · Accepted Answer · 2015-12-19 02:05:07Z

32

It is possible to use the unicode representation (\u00B1):

a <- ggplot()
a <- a + geom_point(aes(x=seq(0,1,0.1), y=seq(0,1,0.1)))
a <- a + annotate("text", x=0.5, y=0.3, label="myplot")
a + annotate("text", x=0.5, y=0.2, label="\u00B1")

Or you can use the ± symbol directly, by copying and pasting it from somewhere.

a + annotate("text", x=0.5, y=0.2, label="±")

edited Dec 19, 2015 at 2:05

answered Dec 19, 2015 at 1:42

Jota

17.6k7 gold badges67 silver badges93 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Ben Bolker · Accepted Answer · 2023-03-26 21:53:03Z

12

This works:

a0 <- ggplot()
a0 <- a0 + geom_point(aes(x=seq(0,1,0.1), y=seq(0,1,0.1)))
a0 + annotate("text", x=0.5, y=0.1, label="'' %+-% '' ", parse=TRUE)

The key idea is that %+-% is an operator, so it has to operate on something, i.e. it has to be in the form x %+-% y; in this case I've made x and y be blank strings.

You could also use phantom():

annotate("text", x=0.5, y=0.1, label = "phantom() %+-% phantom()", parse = TRUE)

If you want to use full LaTeX-style markup like \pm you need to go down the rabbit hole of tikzDevice. However, latex2exp::TeX can often provide a useful hint, e.g.:

latex2exp::TeX("\\pm")
##    LaTeX: \pm 
## plotmath: phantom() %+-% phantom()

edited Mar 26, 2023 at 21:53

answered Dec 19, 2015 at 0:13

Ben Bolker

230k26 gold badges405 silver badges497 bronze badges

2 Comments

rawr Over a year ago

phantom also works, although it is almost completely undocumented

IRTFM Over a year ago

Reading and re-reading the plotmath page is necessary. And actually it is phantom() that is needed.

Collectives™ on Stack Overflow

How to place +/- plus minus operator in text annotation of plot (ggplot2)?

2 Answers 2

Comments

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related