Rotating and spacing axis labels in ggplot2

Question

I have a plot where the x-axis is a factor whose labels are long. While probably not an ideal visualization, for now I'd like to simply rotate these labels to be vertical. I've figured this part out with the code below, but as you can see, the labels aren't totally visible.

data(diamonds)
diamonds$cut <- paste("Super Dee-Duper",as.character(diamonds$cut))
q <- qplot(cut,carat,data=diamonds,geom="boxplot")
q + opts(axis.text.x=theme_text(angle=-90))

Undergo

As ggplot 3.3.0 is out now, IMO the accepted answer should be changed to jan-glxs one – Heliotaxis

Answer 1

Change the last line to

q + theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1))

By default, the axes are aligned at the center of the text, even when rotated. When you rotate +/- 90 degrees, you usually want it to be aligned at the edge instead:

The image above is from this blog post.

Surfboat

In the newest version of ggplot2 the command would be: q + theme(axis.text.x=element_text(angle = -90, hjust = 0)) – Gorlicki

To those for whom hjust is not behaving as described here, try theme(axis.text.x=element_text(angle = 90, vjust = 0.5)). As of ggplot2 0.9.3.1 this seems to be the solution. – Greenhorn

Actually, I had to combine the two solutions above to get correctly aligned labels: q + theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1)) – Lantana

@jupp0r's correct. theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1)) IS THE ONE WORKING CURRENTLY. – Pam

if you wanted 45° rotated labels (easier to read) theme(axis.text.x = element_text(angle = 45, vjust = 1, hjust=1)) gives good results – Ruttger

In my case I have the vjust was 0.3 to really make it look centered q + theme(axis.text.x = element_text(angle = 90, vjust = 0.3, hjust=1)). I am using ezplot from ez package, and using vjust = 0.5 produced a slightly crooked result – Snowonthemountain

In case someone is looking for it, it works also with qplot – Saltwort

How can I use it when I'm using the option geom_bar(stat="identity",position="dodge")? Strangely then it doesn't rotate the labels – Rimarimas

Nowadays, you can simply use guides(x = guide_axis(angle = 90)) + . (see also my answer below) – Ruttger

For better clarity on using hjust and vjust see this excellent post: #7264349 – Arvizu

Answer 2

ggplot 3.3.0 fixes this by providing guide_axis(angle = 90) (as guide argument to scale_.. or as x argument to guides):

library(ggplot2)
data(diamonds)
diamonds$cut <- paste("Super Dee-Duper", as.character(diamonds$cut))

ggplot(diamonds, aes(cut, carat)) +
  geom_boxplot() +
  scale_x_discrete(guide = guide_axis(angle = 90)) +
  # ... or, equivalently:
  # guides(x =  guide_axis(angle = 90)) +
  NULL

From the documentation of the angle argument:

Compared to setting the angle in theme() / element_text(), this also uses some heuristics to automatically pick the hjust and vjust that you probably want.

---

Alternatively, it also provides guide_axis(n.dodge = 2) (as guide argument to scale_.. or as x argument to guides) to overcome the over-plotting problem by dodging the labels vertically. It works quite well in this case:

library(ggplot2)
data(diamonds)
diamonds$cut <- paste("Super Dee-Duper",as.character(diamonds$cut))

ggplot(diamonds, aes(cut, carat)) + 
  geom_boxplot() +
  scale_x_discrete(guide = guide_axis(n.dodge = 2)) +
  NULL

Ruttger

Although I like the dodging solution here, it's worth noting that guide_axis(angle=90) picks the correct vjust and hjust values, which addresses the issue in the OP. – Abdella

@Abdella Thanks, I was not aware and now added this to the answer! – Ruttger

unfortunately this solution doesn't;t play well with ggplotly function as the rotated axis label is not carried over. Only the previous theme() solution works with ggplotly – Nananne

@Nananne yes plotly.R's ggplotly only supports a subset of ggplot's functionality. This question provides an workaround for dodging. – Ruttger

Answer 3

Use coord_flip()

data(diamonds)
diamonds$cut <- paste("Super Dee-Duper",as.character(diamonds$cut))

qplot(cut, carat, data = diamonds, geom = "boxplot") +
  coord_flip()

---

Add str_wrap()

# wrap text to no more than 15 spaces
library(stringr)
diamonds$cut2 <- str_wrap(diamonds$cut, width = 15)
qplot(cut2, carat, data = diamonds, geom = "boxplot") +
  coord_flip()

---

In Ch 3.9 of R for Data Science, Wickham and Grolemund speak to this exact question:

coord_flip() switches the x and y axes. This is useful (for example), if you want horizontal boxplots. It’s also useful for long labels: it’s hard to get them to fit without overlapping on the x-axis.

Embryology

Answer 4

To make the text on the tick labels fully visible and read in the same direction as the y-axis label, change the last line to

q + theme(axis.text.x=element_text(angle=90, hjust=1))

Happiness

Answer 5

I'd like to provide an alternate solution, a robust solution similar to what I am about to propose was required in the latest version of ggtern, since introducing the canvas rotation feature.

Basically, you need to determine the relative positions using trigonometry, by building a function which returns an element_text object, given angle (ie degrees) and positioning (ie one of x,y,top or right) information.

#Load Required Libraries
library(ggplot2)
library(gridExtra)

#Build Function to Return Element Text Object
rotatedAxisElementText = function(angle,position='x'){
  angle     = angle[1]; 
  position  = position[1]
  positions = list(x=0,y=90,top=180,right=270)
  if(!position %in% names(positions))
    stop(sprintf("'position' must be one of [%s]",paste(names(positions),collapse=", ")),call.=FALSE)
  if(!is.numeric(angle))
    stop("'angle' must be numeric",call.=FALSE)
  rads  = (angle - positions[[ position ]])*pi/180
  hjust = 0.5*(1 - sin(rads))
  vjust = 0.5*(1 + cos(rads))
  element_text(angle=angle,vjust=vjust,hjust=hjust)
}

Frankly, in my opinion, I think that an 'auto' option should be made available in ggplot2 for the hjust and vjust arguments, when specifying the angle, anyway, lets demonstrate how the above works.

#Demonstrate Usage for a Variety of Rotations
df    = data.frame(x=0.5,y=0.5)
plots = lapply(seq(0,90,length.out=4),function(a){
  ggplot(df,aes(x,y)) + 
    geom_point() + 
    theme(axis.text.x = rotatedAxisElementText(a,'x'),
          axis.text.y = rotatedAxisElementText(a,'y')) +
    labs(title = sprintf("Rotated %s",a))
})
grid.arrange(grobs=plots)

Which produces the following:

Dawndawna

I do not obtain the same results, for me the axis text is never well adjusted using your auto method. However, using rads = (-angle - positions[[ position ]])*pi/180 produced better placements. Note the additional minus sign before angle. Thanks for the code anyway :) – Shepherd

Get idea! I wanted to adapt your function to be able to run it with any parameters of element_text(). So I added a parameter in the function called element_text_params = list() and replaced the last line in your function by element_text_params <- c(element_text_params, list(angle = angle, vjust = vjust, hjust = hjust))and returned return(do.call(element_text, element_text_params)). That way I can call your function like rotatedAxisElementText(45, "y", element_text_params = list("size" = 10, "face" = "bold") – Druse

Answer 6

OUTDATED - see this answer for a simpler approach

---

To obtain readable x tick labels without additional dependencies, you want to use:

  ... +
  theme(axis.text.x = element_text(angle = 90, hjust = 1, vjust = 0.5)) +
  ...

This rotates the tick labels 90° counterclockwise and aligns them vertically at their end (hjust = 1) and their centers horizontally with the corresponding tick mark (vjust = 0.5).

Full example:

library(ggplot2)
data(diamonds)
diamonds$cut <- paste("Super Dee-Duper",as.character(diamonds$cut))
q <- qplot(cut,carat,data=diamonds,geom="boxplot")
q + theme(axis.text.x = element_text(angle = 90, hjust = 1, vjust = 0.5))

---

Note, that vertical/horizontal justification parameters vjust/hjust of element_text are relative to the text. Therefore, vjust is responsible for the horizontal alignment.

Without vjust = 0.5 it would look like this:

q + theme(axis.text.x = element_text(angle = 90, hjust = 1))

Without hjust = 1 it would look like this:

q + theme(axis.text.x = element_text(angle = 90, vjust = 0.5))

If for some (wired) reason you wanted to rotate the tick labels 90° clockwise (such that they can be read from the left) you would need to use: q + theme(axis.text.x = element_text(angle = -90, vjust = 0.5, hjust = -1)).

All of this has already been discussed in the comments of this answer but I come back to this question so often, that I want an answer from which I can just copy without reading the comments.

Ruttger

Answer 7

The ggpubr package offers a shortcut that does the right thing by default (right align text, middle align text box to tick):

library(ggplot2)
diamonds$cut <- paste("Super Dee-Duper", as.character(diamonds$cut))
q <- qplot(cut, carat, data = diamonds, geom = "boxplot")
q + ggpubr::rotate_x_text()

^{Created on 2018-11-06 by the reprex package (v0.2.1)}

Found with a GitHub search for the relevant argument names: https://github.com/search?l=R&q=element_text+angle+90+vjust+org%3Acran&type=Code

Normandnormandy

Answer 8

An alternative to coord_flip() is to use the ggstance package. The advantage is that it makes it easier to combine the graphs with other graph types and you can, maybe more importantly, set fixed scale ratios for your coordinate system.

library(ggplot2)
library(ggstance)

diamonds$cut <- paste("Super Dee-Duper", as.character(diamonds$cut))

ggplot(data=diamonds, aes(carat, cut)) + geom_boxploth()

^{Created on 2020-03-11 by the reprex package (v0.3.0)}

Extortionary