Paste "25 \%" in R for further processing in LaTeX

Question

I want a character variable in R taking the value from, lets say "a", and adding " \%", to create a %-sign later in LaTeX.

Usually I'd do something like:

a <- 5
paste(a,"\%")

but this fails.

Error: '\%' is an unrecognized escape in character string starting "\%"

Any ideas? A workaround would be to define another command giving the %-sign in LaTeX, but I'd prefer a solution within R.

Answer 1

As many other languages, certain characters in strings have a different meaning when they're escaped. One example for that is \n, which means newline instead of n. When you write \%, R tries to interpret % as a special character and fails doing so. You might want to try to escape the backslash, so that it is just a backslash:

paste(a, "\\%")

You can read on escape sequences here.

Answer 2

You can also look at the latexTranslate function from the Hmisc package, which will escape special characters from strings to make them LaTeX-compatible :

R> latexTranslate("You want to give me 100$ ? I agree 100% !")
[1] "You want to give me 100\\$ ? I agree 100\\% !"