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qp2/ocaml/Bitlist.ml

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OCaml
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2019-01-25 11:39:31 +01:00
open Qptypes
open Core
(*
Type for bits strings
=====================
list of Bits
*)
type t = Bit.t list
(* String representation *)
let to_string b =
let rec do_work accu = function
| [] -> accu
| head :: tail ->
let new_accu = (Bit.to_string head) ^ accu
in do_work new_accu tail
in
do_work "" b
let of_string ?(zero='0') ?(one='1') s =
String.to_list s
|> List.rev_map ~f:( fun c ->
if (c = zero) then Bit.Zero
else if (c = one) then Bit.One
else (failwith ("Error in bitstring ") ) )
let of_string_mp s =
String.to_list s
|> List.rev_map ~f:(function
| '-' -> Bit.Zero
| '+' -> Bit.One
| _ -> failwith ("Error in bitstring ") )
(* Create a bit list from an int64 *)
let of_int64 i =
let rec do_work accu = function
| 0L -> Bit.Zero :: accu |> List.rev
| 1L -> Bit.One :: accu |> List.rev
| i ->
let b =
match (Int64.bit_and i 1L ) with
| 0L -> Bit.Zero
| 1L -> Bit.One
| _ -> raise (Failure "i land 1 not in (0,1)")
in
do_work (b :: accu) (Int64.shift_right_logical i 1)
in
let adjust_length result =
let rec do_work accu = function
| 64 -> List.rev accu
| i when i>64 -> raise (Failure "Error in of_int64 > 64")
| i when i<0 -> raise (Failure "Error in of_int64 < 0")
| i -> do_work (Bit.Zero :: accu) (i+1)
in
do_work (List.rev result) (List.length result)
in
adjust_length (do_work [] i)
(* Create an int64 from a bit list *)
let to_int64 l =
assert ( (List.length l) <= 64) ;
let rec do_work accu = function
| [] -> accu
| Bit.Zero::tail -> do_work Int64.(shift_left accu 1) tail
| Bit.One::tail -> do_work Int64.(bit_or one (shift_left accu 1)) tail
in do_work Int64.zero (List.rev l)
(* Create a bit list from a list of int64 *)
let of_int64_list l =
List.map ~f:of_int64 l
|> List.concat
(* Create a bit list from an array of int64 *)
let of_int64_array l =
Array.map ~f:of_int64 l
|> Array.to_list
|> List.concat
(* Compute n_int *)
let n_int_of_mo_num mo_num =
let bit_kind_size = Bit_kind_size.to_int (Lazy.force Qpackage.bit_kind_size) in
N_int_number.of_int ( (mo_num-1)/bit_kind_size + 1 )
(* Create a zero bit list *)
let zero n_int =
let n_int = N_int_number.to_int n_int in
let a = Array.init n_int (fun i-> 0L) in
of_int64_list ( Array.to_list a )
(* Create an int64 list from a bit list *)
let to_int64_list l =
let rec do_work accu buf counter = function
| [] ->
begin
match buf with
| [] -> accu
| _ -> (List.rev buf)::accu
end
| i::tail ->
if (counter < 64) then
do_work accu (i::buf) (counter+1) tail
else
do_work ( (List.rev (i::buf))::accu) [] 1 tail
in
let l = do_work [] [] 1 l
in
List.rev_map ~f:to_int64 l
(* Create an array of int64 from a bit list *)
let to_int64_array l =
to_int64_list l
|> Array.of_list
(* Create a bit list from a list of MO indices *)
let of_mo_number_list n_int l =
let n_int = N_int_number.to_int n_int in
let length = n_int*64 in
let a = Array.create length (Bit.Zero) in
List.iter ~f:(fun i-> a.((MO_number.to_int i)-1) <- Bit.One) l;
Array.to_list a
let to_mo_number_list l =
let a = Array.of_list l in
let mo_num = MO_number.get_max () in
let rec do_work accu = function
| 0 -> accu
| i ->
begin
let new_accu =
match a.(i-1) with
| Bit.One -> (MO_number.of_int ~max:mo_num i)::accu
| Bit.Zero -> accu
in
do_work new_accu (i-1)
end
in
do_work [] (List.length l)
(* logical operations on bit_list *)
let logical_operator2 op a b =
let rec do_work_binary result a b =
match a, b with
| [], [] -> result
| [], _ | _ , [] -> raise (Failure "Lists should have same length")
| (ha::ta), (hb::tb) ->
let newbit = op ha hb
in do_work_binary (newbit::result) ta tb
in
List.rev (do_work_binary [] a b)
let logical_operator1 op b =
let rec do_work_unary result b =
match b with
| [] -> result
| (hb::tb) ->
let newbit = op hb
in do_work_unary (newbit::result) tb
in
List.rev (do_work_unary [] b)
let and_operator a b = logical_operator2 Bit.and_operator a b
let xor_operator a b = logical_operator2 Bit.xor_operator a b
let or_operator a b = logical_operator2 Bit.or_operator a b
let not_operator b = logical_operator1 Bit.not_operator b
let popcnt b =
List.fold_left b ~init:0 ~f:(fun accu -> function
| Bit.One -> accu+1
| Bit.Zero -> accu
)