Apply function to corresponding elements in list of data frames

Question

I have a list of data frames in R. All of the data frames in the list are of the same size. However, the elements may be of different types. For example,

I would like to apply a function to corresponding elements of data frame. For example, I want to use the paste function to produce a data frame such as

"1a" "2b" "3c"

"4d" "5e" "6f"

Is there a straightforward way to do this in R. I know it is possible to use the Reduce function to apply a function on corresponding elements of dataframes within lists. But using the Reduce function in this case does not seem to have the desired effect.

Reduce(paste,l)

Produces:

"c(1, 4) c(\"a\", \"d\")" "c(2, 5) c(\"b\", \"e\")" "c(3, 6) c(\"c\", \"f\")"

Wondering if I can do this without writing messy for loops. Any help is appreciated!

Answer 1

Instead of Reduce, use Map.

 # not quite the same as your data
 l <- list(data.frame(matrix(1:6,ncol=3)),
           data.frame(matrix(letters[1:6],ncol=3), stringsAsFactors=FALSE))
 # this returns a list
 LL <- do.call(Map, c(list(f=paste0),l))
 #
 as.data.frame(LL)
 #  X1 X2 X3
 # 1 1a 3c 5e
 # 2 2b 4d 6f