Kahan Sum Float Error

KahanSum.fs

// @mdl
let rec kahan_sum_aux (xs : float list) (sum : float) (c : float) =
  match xs with
  | [] -> sum
  | x::xs ->
  let y = x - c in
  let t = sum + y in
  let c = (t - sum) - y in
  kahan_sum_aux xs t c

let kahan_sum (xs : float list) =
  match xs with
  | [] -> 0.0
  | _ -> kahan_sum_aux xs 0.0 0.0

let () =
  let xs = List.replicate 10 0.1 in
  let error_sum = List.fold (+) 0.0 xs in
  let compensated_sum = kahan_sum xs in
  printfn "error_sum = 1.0: %b\ncompensated_sum = 1.0: %b"
    (error_sum = 1.0) (compensated_sum = 1.0)