F# convert array to array of tuples

Question

Let's say I have an array

let arr = [|1;2;3;4;5;6|]

I would like to convert it to something like

[|(1,2);(3,4);(5,6)|]

I've seen Seq.window but this one is going to generate something like

[|(1,2);(2,3);(3,4);(4,5);(5,6)|]

which is not what I want

Answer 1

You can use Array.chunkBySize and then map each sub-array into tuples:

let input = [|1..10|]
Array.chunkBySize 2 list |> Array.map (fun xs -> (xs.[0], xs.[1]))

Answer 2

@Slugart's accepted answer is the best approach (IMO) assuming you know that the array has an even number of elements, but here's another approach that doesn't throw an exception if there does happen to be an odd number (it just omits the last trailing element):

let arr = [|1;2;3;4;5|]
seq { for i in 0 .. 2 .. arr.Length - 2 -> (arr.[i], arr.[i+1]) } |> Seq.toArray