Row names & column names in R
Do the following function pairs generate exactly the same results?
Pair 1) names() & colnames()
Pair 2) rownames() & row.names()
Answer
As Oscar Wilde said
Consistency is the last refuge of the unimaginative.
R is more of an evolved rather than designed language, so these things happen. names() and colnames() work on a data.frame but names() does not work on a matrix:
R> DF <- data.frame(foo=1:3, bar=LETTERS[1:3])
R> names(DF)
[1] "foo" "bar"
R> colnames(DF)
[1] "foo" "bar"
R> M <- matrix(1:9, ncol=3, dimnames=list(1:3, c("alpha","beta","gamma")))
R> names(M)
NULL
R> colnames(M)
[1] "alpha" "beta" "gamma"
R>