Adding a calculation to the title of a ggplot

Question

I'm new to R and wondering if the following is possible to calculation in the title of a ggplot scatter. The code below is how I thought it might be possible.

AlexPlot + ggtitle("Alex's BG, The average is " + mean(Alex$bg, na.rm = TRUE))

Try `ggtitle(paste0("Alex's BG, The average is ", paste0(mean(Alex$bg, na.rm = TRUE))))` — Jamie, Nov 22 '22 at 17:54
Thank you but recived error "Error in +ggtitle(paste0("Alex's BG, The average is ", paste0(mean(Alex$bg, : invalid argument to unary operator" — Kevin Cranfield, Nov 22 '22 at 17:59
Please post the rest of your code or something that is reproducible. That error is likely due to something else. ie. you may have too many `+` or are using them in the wrong place — Jamie, Nov 22 '22 at 18:03
sorry I must have miss-typed tried again and it worked thank you — Kevin Cranfield, Nov 22 '22 at 18:09

score 1 · Accepted Answer · answered Nov 22 '22 at 18:37

Since you haven't shared your data, I am using mpg dataset; you need to wrap the text and the numeric calculation within paste function. The comment above works as well, but I am not sure why we need to use paste0 twice!

library(ggplot2)

ggplot(mpg) + 
  geom_point(aes(hwy, displ)) +
  ggtitle(paste("Average mpg is", round(mean(mpg$hwy, na.rm = TRUE),2)))

As you can see, this works. You need to share a reproducible example of your data, if you get an error related to your specific data.

Adding a calculation to the title of a ggplot

1 Answers1