How do you take a vector in R, and paste the individual elements together? Easy, a loop. No, bad! **slap on the wrist** Here’s an example why not.
So let’s start by concatenating a few character strings and showing some examples using base::paste:
a <- c("something", "to", "paste")
[1] "something" "to" "paste"
> paste(a, sep="_") [1] "something" "to" "paste"
> paste(a, collapse="_") [1] "something_to_paste"
> paste(a, sep="_", collapse="-") [1] "something-to-paste"
And there we have it, a simple example demonstrating the difference between a separator expression and a collapse expression without using a hideous loop.
So finally the moral: read the help pages!
