[R-Forge #5688] Column subset on DTs with duplicate names by index still returns first dup column

[arunsrinivasan]

Submitted by: Arun ; Assigned to: Arun ; R-Forge link

Best with an example:

require(data.table) ## 1.9.3
DT <- data.table(x=1:5, x=6:10)
DT[, 1:2, with=FALSE]

It's clear that the columns to choose are 1st and 2nd. Still, it gives back just the first column:

   x x
1: 1 1
2: 2 2
3: 3 3
4: 4 4
5: 5 5

data.frame does this very nicely, although it renames the columns (which we don't have to do).

as.data.frame(DT)[, 1:2]
  x x.1
1 1   6
2 2   7
3 3   8
4 4   9
5 5  10

[arunsrinivasan]

Also updated this SO post and here's the commit that fixed handling duplicate names: 9f0a7f8