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Ingy döt Net 2013-04-10 23:57:08 -07:00
parent 47bf37c096
commit b83f433714
12433 changed files with 156208 additions and 123 deletions
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30
Task/Probabilistic-choice/OCaml/probabilistic-choice.ocaml Normal file
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let p = [
"Aleph", 1.0 /. 5.0;
"Beth", 1.0 /. 6.0;
"Gimel", 1.0 /. 7.0;
"Daleth", 1.0 /. 8.0;
"He", 1.0 /. 9.0;
"Waw", 1.0 /. 10.0;
"Zayin", 1.0 /. 11.0;
"Heth", 1759.0 /. 27720.0;
]
let rec take k = function
| (v, p)::tl -> if k < p then v else take (k -. p) tl
| _ -> invalid_arg "take"
let () =
let n = 1_000_000 in
Random.self_init();
let h = Hashtbl.create 3 in
List.iter (fun (v, _) -> Hashtbl.add h v 0) p;
let tot = List.fold_left (fun acc (_, p) -> acc +. p) 0.0 p in
for i = 1 to n do
let sel = take (Random.float tot) p in
let n = Hashtbl.find h sel in
Hashtbl.replace h sel (succ n) (* count the number of each item *)
done;
List.iter (fun (v, p) ->
let d = Hashtbl.find h v in
Printf.printf "%s \t %f %f\n" v p (float d /. float n)
) p