Trying to append col.name on to a vector

I have several functions that I am tryin开发者_如何学Gog to implement in R(studio). I will show the simplest one. I am trying to append names on to a vector for later use as a col.name.

# Initialize
headerA <- vector(mode="character",length=20)
headerA[1]="source";headerA[2]="matches"

# Function - add on new name
h <- function(df, compareA, compareB) {
   new_header <- paste(compareA,"Vs",compareB,sep="_")
   data.frame(df,new_header)
}
# Comparison 1:
compareA <-"AA"
compareB <-"BB"
headers <- (headerA, compareA, compareB)

But I am getting this error and it is very puzzling. I have googled it but the search is too vague/broad.

When run I get:

headers <- (headerA, compareA, compareB)

Error: unexpected ',' in "headers <- (headerA,"

The second error for the other function is similar...

It looks like you're missing a call to your function h and just have an open ( instead:

headers <- h(headerA, compareA, compareB)

Results in:

        df new_header
1   source   AA_Vs_BB
2  matches   AA_Vs_BB
3            AA_Vs_BB
4            AA_Vs_BB
...