What does the "+" sign mean in RStudio? Most lines start with > but others start with + (for continue line I think). I'm reading along in a book and it is writing arguments for functions on separate lines but I'm not sure how to do that.
Or sometimes I see code like
> mtcars %>%
+ group_by(cyl) %>%
+ summarize(mean(mpg))
As Richard Scriven stated, + is shown at the start of continuation lines. That is, when you pressed Enter without completing the R expression that you were typing. This is the case in all R IDEs (R GUI, Architect, etc.), not just RStudio.
The value that is printed is a global option: you can retrieve it using getOption("continue") and change it with the options function. I keep it set to spaces in order to make it easier to copy code from the command line to a script.
options(continue = " ")
On Stack Overflow and other forums, most people will edit the posted code to remove the start-of-line characters (> on the first line of a command, + on additional lines for the same command). But sometimes you will encounter code without those symbols already removed - you will need to remove them yourself before copy/pasting the code into a script or your R console.
