How can two strings be concatenated?

Hans picture Hans · Aug 26, 2011 · Viewed 693.4k times · Source

How can I concatenate (merge, combine) two values? For example I have:

tmp = cbind("GAD", "AB")
tmp
#      [,1]  [,2]
# [1,] "GAD" "AB"

My goal is to concatenate the two values in "tmp" to one string:

tmp_new = "GAD,AB"

Which function can do this for me?

Answer

Rainer picture Rainer · Aug 26, 2011
paste()

is the way to go. As the previous posters pointed out, paste can do two things:

concatenate values into one "string", e.g.

> paste("Hello", "world", sep=" ")
[1] "Hello world"

where the argument sep specifies the character(s) to be used between the arguments to concatenate, or collapse character vectors

> x <- c("Hello", "World")
> x
[1] "Hello" "World"
> paste(x, collapse="--")
[1] "Hello--World"

where the argument collapse specifies the character(s) to be used between the elements of the vector to be collapsed.

You can even combine both:

> paste(x, "and some more", sep="|-|", collapse="--")
[1] "Hello|-|and some more--World|-|and some more"

Hope this helps.