Is there a way to paste together the elements of a vector in R without using a loop?

r paste memory-efficient
Max picture Max · Jul 14, 2011 · Viewed 46.2k times · Source

Say there's a vector x:

x <- c("a", " ", "b")

and I want to quickly turn this into a single string "a b". Is there a way to do this without a loop? I know with a loop I could do this:

y <- ""
for (i in 1:3){
    paste(y, x[i], sep = "")
}

> y
[1] "a b"

but I will need to do this over many, many iterations, and having to loop over this and replace the original with the new each time would become very time consuming. I always want to be able to do something like this:

x <- paste(x)

as if paste() could smartly divide up the elements of a vector itself, but I know it can't. Is there another function, or a more creative way to use paste(), which can accomplish this efficiently?

Answer

joran picture joran · Jul 14, 2011

You just need to use the collapse argument:

paste(x,collapse="")

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