Force R not to use exponential notation (e.g. e+10)?

Question

This is a bit of a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):

‘scipen’: integer. A penalty to be applied when deciding to print numeric values in fixed or exponential notation. Positive values bias towards fixed and negative towards scientific notation: fixed notation will be preferred unless it is more than ‘scipen’ digits wider.

Example:

R> ran2 <- c(1.810032e+09, 4) 
R> options("scipen"=-100, "digits"=4)
R> ran2
[1] 1.81e+09 4.00e+00
R> options("scipen"=100, "digits"=4)
R> ran2
[1] 1810032000          4

That said, I still find it fudgeworthy. The most direct way is to use sprintf() with explicit width e.g. sprintf("%.5f", ran2).

It can be achieved by disabling scientific notation in R.

options(scipen = 999)

My favorite answer:

format(1810032000, scientific = FALSE)
# [1] "1810032000"

This gives what you want without having to muck about in R settings.

Note that it returns a character string rather than a number object

Put options(scipen = 999) in your .Rprofile file so it gets auto-executed by default. (Do not rely on doing it manually.)

(This is saying something different to other answers: how?

1. This keeps things sane when you thunk between multiple projects, multiple languages on a daily or monthly basis. Remembering to type in your per-project settings is error-prone and not scalable. You can have a global ~/.Rprofile or per-project .Rprofile. Or both, with the latter overriding the former.
2. Keeping all your config in a project-wide or global .Rprofile auto-executes it. This is useful for e.g. default package loads, data.table configuration, environment etc. Again, that config can run to a page of settings, and there's zero chance you'll remember those and their syntax and type them in