R, ggplot: Decimals on y-axis

Question

I want to produce a bar plot, similar to this MWE:

library(tidyverse)
library(ggplot2)

mtcars %>% 
  mutate(mpg=mpg/1000) %>% 
  ggplot(aes(x=cyl, y=mpg)) +
  geom_bar(stat="identity") +
  scale_y_continuous(labels = scales::percent)

What I get is the following (keep in mind that it is nonsense, but serves illustration purposes): Now, I want the decimals replaced from the percentages on the y-axis ("30%" instead of "30.0%"). What can I do?

I have found a similar question here, but couldn't make the function NRPercent does not work (and can't comment there).

See the question linked to as a possible duplicate, but also look at `?scales::percent`. The function you're using for labeling multiplies values by 100 and tacks on a percent sign, so a number like 0.0125 will come out as 1.25% by default. There's an argument for setting the accuracy to drop the decimals. — camille, Sep 05 '18 at 14:16

score 24 · Accepted Answer · answered Sep 05 '18 at 14:23

24

With the new version of scales you can use:

scale_y_continuous(labels = scales::percent_format(accuracy = 1))

answered Sep 05 '18 at 14:23

Axeman

32,068
8
81
94

score 2 · Answer 2 · edited Sep 05 '18 at 15:24

2

Here is a post that would help out : How do I change the number of decimal places on axis labels in ggplot2?

I posted the solution here just so you have it here. Added percent sign to values.

mtcars %>% 
  mutate(mpg=mpg/1000) %>% 
  ggplot(aes(x=cyl, y=mpg*100)) +
  geom_bar(stat="identity") +
  scale_y_continuous("Percent", labels = function(x) paste0(sprintf("%.0f", x),"%"))

edited Sep 05 '18 at 15:24

Axeman

32,068
8
81
94

answered Sep 05 '18 at 14:03

Mike

3,797
1
11
30

1

Thanks, updated the answer to include percent sign. – Mike Sep 05 '18 at 15:20
This works; however, line 2 and 3 can be clarified to `mutate(mpg) %>%` `ggplot(aes(x=cyl, y=mpg/10)` – Lukas Sep 07 '18 at 08:12
1

@Lukas, in that case there is no need for the `mutate` at all! Just `ggplot(mtcars, aes(........` – Axeman Sep 07 '18 at 11:19

R, ggplot: Decimals on y-axis

2 Answers2