R: How to concatenate vectors of strings in a list of vectors

Question

I have a list of vectors of strings like this:

x=list(c("a","b"),"c",c("d","e","f"),c("gg","hh") )

I'd like to concatenate the vectors into single strings like this

y=c("ab","c","def","gghh")

I searched around but I couldn't find a similar example. Is there a smart way to do this without looping over the list elements?

score 6 · Accepted Answer · answered Jun 29 '18 at 17:02

6

With sapply:

y <- sapply(x, paste0, collapse = '')
# [1] "ab"   "c"    "def"  "gghh"

answered Jun 29 '18 at 17:02

acylam

2

You probably know this already, but FYI for those interested, `paste0` and `paste` will give the same result in cases like this where there's only one argument (other than `collapse`) – IceCreamToucan Jun 29 '18 at 17:06

score -1 · Answer 2 · answered Jun 29 '18 at 17:00

-1

It's not the most elegant solution but this works:

x=list(c("a","b"),"c",c("d","e","f"),c("gg","hh") )

y=NULL
for(i in 1:length(x)){
  y=c(y,paste0(x[[i]],collapse=""))
}

answered Jun 29 '18 at 17:00

Fino

2 Answers2