Count_lists.ml

open Lacaml.D

let capture_failure_of_list = function
  | [] -> Mat.empty
  | (h :: _) as lst ->
    let m = List.length lst in
    let n = List.length h in
    let mat = Mat.create m n in
    let rec loop i = function
      | [] -> mat
      | h :: t ->
        let s = List.fold_left (fun j e -> mat.{i, j} <- e; j + 1) 1 h in
        if s <= n then
          invalid_arg "list not long enough"
        else
          loop (i + 1) t
    in
    try loop 1 lst
    with Invalid_argument _ ->
      failwith "of_list: vectors not of same length"

let count_first_of_list = function
  | [] -> Mat.empty
  | (h :: t) as lst ->
    let m = List.length lst in
    let n = List.length h in
    let () = List.iter (fun l ->
        if List.length l <> n then
          failwith "of_list: vectors not of same length"
        else
          ()) t
    in
    let mat = Mat.create m n in
    let rec loop i = function
      | [] -> mat
      | h :: t ->
        let () = List.iteri (fun j e -> mat.{i, j + 1} <- e) h in
        loop (i + 1) t
    in
    loop 1 lst

let linit n f =
  let rec loop i acc =
    if i < 0 then acc
    else loop (i - 1) (f i :: acc)
  in
  loop (n - 1) []
  
let linit2 n m f =
  linit n (fun _ -> linit m f)

let append_sub n at =
  List.mapi (fun i lst -> if i = at then n :: lst else lst)

let test_sample n m =
  append_sub (float m) (Random.int n) (linit2 n m float)

let time f =
  let n = Sys.time () in
  let r = f () in
  Printf.printf "%f\n" (Sys.time () -. n);
  r

let test n m times f =
  let data = linit times (fun _ -> test_sample n m) in
  let conv () =
    List.iter (fun lst ->
        try f lst; assert false
        with Failure _ -> ())
      data
  in
  time conv

let () =
  let n = int_of_string (Sys.argv.(1)) in
  let m = int_of_string (Sys.argv.(2)) in
  let times = 1000 in
  Random.self_init ();
  Printf.printf "Testing %d %d %d capture_failure_of_list\n" n m times;
  test n m times capture_failure_of_list; 
  Printf.printf "Testing %d %d %d count_first_of_list\n" n m times;
  test n m times count_first_of_list