Function that returns its argument, named by itself

Question

Is there a function in base R or a package which takes a list as argument and returns this list with the names set to the list items? Something along these lines:

named.list <- function(l) { names(l) <- l; l }

This is useful for the l?ply functions in plyr -- these functions keep the names of the argument list. Compare:

llply(c('a', 'b', 'c'), function(x) paste0('(', x, ')'))

 [[1]]
 [1] "(a)"

 [[2]]
 [1] "(b)"

 [[3]]
 [1] "(c)"

llply(named.list(c('a', 'b', 'c')), function(x) paste0('(', x, ')'))

 $a
 [1] "(a)"

 $b
 [1] "(b)"

 $c
 [1] "(c)"

Not quite clear what your question is. Does `?setNames` help? — Arun, Mar 14 '13 at 21:00

score 2 · Answer 1 · answered Mar 14 '13 at 21:01

2

Do you want this for example?:

ll <- c('a', 'b', 'c')
ll <- setNames(ll,ll)
 ll
  a   b   c 
"a" "b" "c"

answered Mar 14 '13 at 21:01

agstudy

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Function that returns its argument, named by itself

1 Answers1