[R] col.names in as.data.frame() ?

[Boris Steipe]

I have been trying to create a data frame from some structured text in a single expression. Reprex:

nouns <- as.data.frame(
  matrix(c(
    "gaggle",
    "geese",
    
    "dule",
    "doves",
    
    "wake",
    "vultures"
  ), ncol = 2, byrow = TRUE),
  col.names = c("collective", "category")
)

But ... :

> str(nouns)
'data.frame':	3 obs. of  2 variables:
 $ V1: chr  "gaggle" "dule" "wake"
 $ V2: chr  "geese" "doves" "vultures"

i.e. the col.names argument does nothing. From my reading of ?as.data.frame, my example should have worked.

I know how to get the required result with colnames(), but I would like to understand why the idiom as written didn't work, and how I could have known that from the help file.


Thanks!
Boris