knitr displaying digits of an integer without scientific notation

Question

when displaying a number with inline-code with more than four digits like

`r 21645`

the result in a knitted html-file is this: 2.164510^{4} (in reality inside the inline-hook there is a calculation going on which results in 21645). Even though I just want it to print the number, like so: 21645. I can easily fix this for one instance wrapping it inside as.integer or format or print, but how do I set an option for the whole knitr-document so that it prints whole integers as such (all I need is to print 5 digits)? Doing this by hand gets very annoying. Setting options(digits = 7) doesnt help. I am guessing I would have to set some chunk-optionor define a hook, but I have no idea how

Answer 1

Note that if you type your numeric as integer it will be well formatted:

`r 21645L`

Of course you can always set an inline hook for more flexibility( even it is better to set globally options as in your answer):

```{r}
inline_hook <- function(x) {
  if (is.numeric(x)) {
    format(x, digits = 2)
  } else x
}
knitr::knit_hooks$set(inline = inline_hook)

```

Answer 2

I already solved it, just including the following line of code inside the setoptions-chunk in the beginning of a knitr document:

options(scipen=999)

resolves the issue, like one can read inside this answer from @Paul Hiemstra:

https://stackoverflow.com/a/25947542/4061993

from the documentation of ?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.

Answer 3

If you don't want to display scientific notation in this instance, but also don't want to disable it completely for your knitr report, you can use format() and set scientific=FALSE:

`r format(21645, scientific=FALSE)`