Number formatting axis labels in ggplot2?
RGgplot2R Problem Overview
I'm plotting a fairly simple chart using ggplot2 0.9.1.
x <- rnorm(100, mean=100, sd = 1) * 1000000
y <- rnorm(100, mean=100, sd = 1) * 1000000
df <- data.frame(x,y)
p.new <- ggplot(df,aes(x,y)) +
geom_point()
print(p.new)
Which works, but ggplot2 defaults to scientific notation that is inappropriate for my audience. If I want to change the x-axis label format by entering:
p.new + scale_x_continuous(labels = comma)
I get:
>Error in structure(list(call = match.call(), aesthetics = aesthetics, : object 'comma' not found
What am I doing wrong? I note that the language changed recently from "formatter" to "labels". Perhaps I'm misreading the man page?
Edit: I was indeed misreading the man page
Need to load library(scales)
before attempting this.
R Solutions
Solution 1 - R
One needs to load library(scales)
before attempting this.
Solution 2 - R
More generally, you can control some nice parameters using the "scales" package. One of its functions is number_format().
library(ggplot2)
library(scales)
p <- ggplot(mpg, aes(displ, cty)) + geom_point()
For formatting your numbers, you can use the function number_format(). It offers some nice possibilities, such as controlling the number of decimals (here 2 decimals) and your decimal mark (here ',' instead of '.')
p + scale_y_continuous(
labels = scales::number_format(accuracy = 0.01,
decimal.mark = ','))
Solution 3 - R
Here is an example of how to add commas and decimals to ggplot using scales::comma_format()
.
Essentially allowing for a prettyNum() style of formatting.
Seatbelts_df <- as.data.frame(Seatbelts)
ggplot(data=Seatbelts_df, aes(x=Seatbelts_df$drivers, y=Seatbelts_df$DriversKilled, color=factor(Seatbelts_df$law))) +
geom_jitter(alpha=0.5) +
theme(plot.title=element_text(face="bold")) +
labs(title="Amount of Drivers on Road vs Amount of deaths", subtitle = "Dataset from package datasets::Seatbelts", x ="Drivers on Road", y="Amount of Deaths", color="Seatbelt Law?") +
scale_color_manual(labels = c("Yes", "No"), values = c("blue", "red")) +
geom_vline(aes(xintercept=mean(Seatbelts_df$drivers)), color="black", linetype="dashed", size=1) +
scale_x_continuous(
labels = scales::comma_format(big.mark = ',',
decimal.mark = '.'))