ocaml/otherlibs/num/num.ml

396 lines
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OCaml

(***********************************************************************)
(* *)
(* Objective Caml *)
(* *)
(* Valerie Menissier-Morain, projet Cristal, INRIA Rocquencourt *)
(* *)
(* Copyright 1996 Institut National de Recherche en Informatique et *)
(* en Automatique. All rights reserved. This file is distributed *)
(* under the terms of the GNU Library General Public License. *)
(* *)
(***********************************************************************)
(* $Id$ *)
open Int_misc
open Nat
open Big_int
open Arith_flags
open Ratio
type num = Int of int | Big_int of big_int | Ratio of ratio
(* The type of numbers. *)
let biggest_INT = big_int_of_int biggest_int
and least_INT = big_int_of_int least_int
(* Coercion big_int -> num *)
let num_of_big_int bi =
if le_big_int bi biggest_INT & ge_big_int bi least_INT
then Int (int_of_big_int bi)
else Big_int bi
let numerator_num = function
Ratio r -> normalize_ratio r; num_of_big_int (numerator_ratio r)
| n -> n
let denominator_num = function
Ratio r -> normalize_ratio r; num_of_big_int (denominator_ratio r)
| n -> Int 1
let normalize_num = function
Int i -> Int i
| Big_int bi -> num_of_big_int bi
| Ratio r -> if is_integer_ratio r
then num_of_big_int (numerator_ratio r)
else Ratio r
let cautious_normalize_num_when_printing n =
if (!normalize_ratio_when_printing_flag) then (normalize_num n) else n
let num_of_ratio r =
normalize_ratio r;
if not (is_integer_ratio r) then Ratio r
else if is_int_big_int (numerator_ratio r) then
Int (int_of_big_int (numerator_ratio r))
else Big_int (numerator_ratio r)
(* Operations on num *)
let add_num a b = match (a,b) with
((Int int1), (Int int2)) ->
let r = int1 + int2 in
if (int1 lxor int2) lor (int1 lxor (r lxor (-1))) < 0
then Int r (* No overflow *)
else Big_int(add_big_int (big_int_of_int int1) (big_int_of_int int2))
| ((Int i), (Big_int bi)) ->
num_of_big_int (add_int_big_int i bi)
| ((Big_int bi), (Int i)) ->
num_of_big_int (add_int_big_int i bi)
| ((Int i), (Ratio r)) ->
Ratio (add_int_ratio i r)
| ((Ratio r), (Int i)) ->
Ratio (add_int_ratio i r)
| ((Big_int bi1), (Big_int bi2)) -> num_of_big_int (add_big_int bi1 bi2)
| ((Big_int bi), (Ratio r)) ->
Ratio (add_big_int_ratio bi r)
| ((Ratio r), (Big_int bi)) ->
Ratio (add_big_int_ratio bi r)
| ((Ratio r1), (Ratio r2)) -> num_of_ratio (add_ratio r1 r2)
let ( +/ ) = add_num
let minus_num = function
Int i -> if i = monster_int
then Big_int (minus_big_int (big_int_of_int i))
else Int (-i)
| Big_int bi -> Big_int (minus_big_int bi)
| Ratio r -> Ratio (minus_ratio r)
let sub_num n1 n2 = add_num n1 (minus_num n2)
let ( -/ ) = sub_num
let mult_num a b = match (a,b) with
((Int int1), (Int int2)) ->
if num_bits_int int1 + num_bits_int int2 < length_of_int
then Int (int1 * int2)
else num_of_big_int (mult_big_int (big_int_of_int int1)
(big_int_of_int int2))
| ((Int i), (Big_int bi)) ->
num_of_big_int (mult_int_big_int i bi)
| ((Big_int bi), (Int i)) ->
num_of_big_int (mult_int_big_int i bi)
| ((Int i), (Ratio r)) ->
num_of_ratio (mult_int_ratio i r)
| ((Ratio r), (Int i)) ->
num_of_ratio (mult_int_ratio i r)
| ((Big_int bi1), (Big_int bi2)) ->
num_of_big_int (mult_big_int bi1 bi2)
| ((Big_int bi), (Ratio r)) ->
num_of_ratio (mult_big_int_ratio bi r)
| ((Ratio r), (Big_int bi)) ->
num_of_ratio (mult_big_int_ratio bi r)
| ((Ratio r1), (Ratio r2)) ->
num_of_ratio (mult_ratio r1 r2)
let ( */ ) = mult_num
let square_num = function
Int i -> if 2 * num_bits_int i < length_of_int
then Int (i * i)
else num_of_big_int (square_big_int (big_int_of_int i))
| Big_int bi -> Big_int (square_big_int bi)
| Ratio r -> Ratio (square_ratio r)
let div_num n1 n2 =
match n1 with
| Int i1 ->
begin match n2 with
| Int i2 ->
num_of_ratio (create_ratio (big_int_of_int i1) (big_int_of_int i2))
| Big_int bi2 -> num_of_ratio (create_ratio (big_int_of_int i1) bi2)
| Ratio r2 -> num_of_ratio (div_int_ratio i1 r2) end
| Big_int bi1 ->
begin match n2 with
| Int i2 -> num_of_ratio (create_ratio bi1 (big_int_of_int i2))
| Big_int bi2 -> num_of_ratio (create_ratio bi1 bi2)
| Ratio r2 -> num_of_ratio (div_big_int_ratio bi1 r2) end
| Ratio r1 ->
begin match n2 with
| Int i2 -> num_of_ratio (div_ratio_int r1 i2)
| Big_int bi2 -> num_of_ratio (div_ratio_big_int r1 bi2)
| Ratio r2 -> num_of_ratio (div_ratio r1 r2) end
;;
let ( // ) = div_num
let floor_num = function
Int i as n -> n
| Big_int bi as n -> n
| Ratio r -> num_of_big_int (floor_ratio r)
let quo_num x y = floor_num (div_num x y)
let mod_num x y = sub_num x (mult_num y (quo_num x y))
let power_num_int a b = match (a,b) with
((Int i), n) ->
(match sign_int n with
0 -> Int 1
| 1 -> num_of_big_int (power_int_positive_int i n)
| _ -> Ratio (create_normalized_ratio
unit_big_int (power_int_positive_int i (-n))))
| ((Big_int bi), n) ->
(match sign_int n with
0 -> Int 1
| 1 -> num_of_big_int (power_big_int_positive_int bi n)
| _ -> Ratio (create_normalized_ratio
unit_big_int (power_big_int_positive_int bi (-n))))
| ((Ratio r), n) ->
(match sign_int n with
0 -> Int 1
| 1 -> Ratio (power_ratio_positive_int r n)
| _ -> Ratio (power_ratio_positive_int
(inverse_ratio r) (-n)))
let power_num_big_int a b = match (a,b) with
((Int i), n) ->
(match sign_big_int n with
0 -> Int 1
| 1 -> num_of_big_int (power_int_positive_big_int i n)
| _ -> Ratio (create_normalized_ratio
unit_big_int
(power_int_positive_big_int i (minus_big_int n))))
| ((Big_int bi), n) ->
(match sign_big_int n with
0 -> Int 1
| 1 -> num_of_big_int (power_big_int_positive_big_int bi n)
| _ -> Ratio (create_normalized_ratio
unit_big_int
(power_big_int_positive_big_int bi (minus_big_int n))))
| ((Ratio r), n) ->
(match sign_big_int n with
0 -> Int 1
| 1 -> Ratio (power_ratio_positive_big_int r n)
| _ -> Ratio (power_ratio_positive_big_int
(inverse_ratio r) (minus_big_int n)))
let power_num a b = match (a,b) with
(n, (Int i)) -> power_num_int n i
| (n, (Big_int bi)) -> power_num_big_int n bi
| _ -> invalid_arg "power_num"
let ( **/ ) = power_num
let is_integer_num = function
Int _ -> true
| Big_int _ -> true
| Ratio r -> is_integer_ratio r
(* integer_num, floor_num, round_num, ceiling_num rendent des nums *)
let integer_num = function
Int i as n -> n
| Big_int bi as n -> n
| Ratio r -> num_of_big_int (integer_ratio r)
and round_num = function
Int i as n -> n
| Big_int bi as n -> n
| Ratio r -> num_of_big_int (round_ratio r)
and ceiling_num = function
Int i as n -> n
| Big_int bi as n -> n
| Ratio r -> num_of_big_int (ceiling_ratio r)
(* Comparisons on nums *)
let sign_num = function
Int i -> sign_int i
| Big_int bi -> sign_big_int bi
| Ratio r -> sign_ratio r
let eq_num a b = match (a,b) with
((Int int1), (Int int2)) -> int1 = int2
| ((Int i), (Big_int bi)) -> eq_big_int (big_int_of_int i) bi
| ((Big_int bi), (Int i)) -> eq_big_int (big_int_of_int i) bi
| ((Int i), (Ratio r)) -> eq_big_int_ratio (big_int_of_int i) r
| ((Ratio r), (Int i)) -> eq_big_int_ratio (big_int_of_int i) r
| ((Big_int bi1), (Big_int bi2)) -> eq_big_int bi1 bi2
| ((Big_int bi), (Ratio r)) -> eq_big_int_ratio bi r
| ((Ratio r), (Big_int bi)) -> eq_big_int_ratio bi r
| ((Ratio r1), (Ratio r2)) -> eq_ratio r1 r2
let ( =/ ) = eq_num
let ( <>/ ) a b = not(eq_num a b)
let compare_num a b = match (a,b) with
((Int int1), (Int int2)) -> compare_int int1 int2
| ((Int i), (Big_int bi)) -> compare_big_int (big_int_of_int i) bi
| ((Big_int bi), (Int i)) -> compare_big_int bi (big_int_of_int i)
| ((Int i), (Ratio r)) -> compare_big_int_ratio (big_int_of_int i) r
| ((Ratio r), (Int i)) -> -(compare_big_int_ratio (big_int_of_int i) r)
| ((Big_int bi1), (Big_int bi2)) -> compare_big_int bi1 bi2
| ((Big_int bi), (Ratio r)) -> compare_big_int_ratio bi r
| ((Ratio r), (Big_int bi)) -> -(compare_big_int_ratio bi r)
| ((Ratio r1), (Ratio r2)) -> compare_ratio r1 r2
let lt_num num1 num2 = compare_num num1 num2 < 0
and le_num num1 num2 = compare_num num1 num2 <= 0
and gt_num num1 num2 = compare_num num1 num2 > 0
and ge_num num1 num2 = compare_num num1 num2 >= 0
let ( </ ) = lt_num
and ( <=/ ) = le_num
and ( >/ ) = gt_num
and ( >=/ ) = ge_num
let max_num num1 num2 = if lt_num num1 num2 then num2 else num1
and min_num num1 num2 = if gt_num num1 num2 then num2 else num1
(* Coercions with basic types *)
(* Coercion with int type *)
let int_of_num = function
Int i -> i
| Big_int bi -> int_of_big_int bi
| Ratio r -> int_of_ratio r
and num_of_int i =
if i = monster_int
then Big_int (big_int_of_int i)
else Int i
(* Coercion with nat type *)
let nat_of_num = function
Int i -> nat_of_int i
| Big_int bi -> nat_of_big_int bi
| Ratio r -> nat_of_ratio r
and num_of_nat nat =
if (is_nat_int nat 0 (length_nat nat))
then Int (nth_digit_nat nat 0)
else Big_int (big_int_of_nat nat)
(* Coercion with big_int type *)
let big_int_of_num = function
Int i -> big_int_of_int i
| Big_int bi -> bi
| Ratio r -> big_int_of_ratio r
(* Coercion with ratio type *)
let ratio_of_num = function
Int i -> ratio_of_int i
| Big_int bi -> ratio_of_big_int bi
| Ratio r -> r;;
let string_of_big_int_for_num bi =
if !approx_printing_flag
then approx_big_int !floating_precision bi
else string_of_big_int bi
(* Coercion with string type *)
(* XL: suppression de sys_string_of_num *)
let string_of_normalized_num = function
Int i -> string_of_int i
| Big_int bi -> string_of_big_int_for_num bi
| Ratio r -> string_of_ratio r
let string_of_num n =
string_of_normalized_num (cautious_normalize_num_when_printing n)
let num_of_string s =
try
let flag = !normalize_ratio_flag in
normalize_ratio_flag := true;
let r = ratio_of_string s in
normalize_ratio_flag := flag;
if eq_big_int (denominator_ratio r) unit_big_int
then num_of_big_int (numerator_ratio r)
else Ratio r
with Failure _ ->
failwith "num_of_string"
(* Coercion with float type *)
let float_of_num = function
Int i -> float i
| Big_int bi -> float_of_big_int bi
| Ratio r -> float_of_ratio r
(* XL: suppression de num_of_float, float_num *)
let succ_num = function
Int i -> if i = biggest_int
then Big_int (succ_big_int (big_int_of_int i))
else Int (succ i)
| Big_int bi -> num_of_big_int (succ_big_int bi)
| Ratio r -> Ratio (add_int_ratio 1 r)
and pred_num = function
Int i -> if i = monster_int
then Big_int (pred_big_int (big_int_of_int i))
else Int (pred i)
| Big_int bi -> num_of_big_int (pred_big_int bi)
| Ratio r -> Ratio (add_int_ratio (-1) r)
let abs_num = function
Int i -> if i = monster_int
then Big_int (minus_big_int (big_int_of_int i))
else Int (abs i)
| Big_int bi -> Big_int (abs_big_int bi)
| Ratio r -> Ratio (abs_ratio r)
let approx_num_fix n num = approx_ratio_fix n (ratio_of_num num)
and approx_num_exp n num = approx_ratio_exp n (ratio_of_num num)
let incr_num r = r := succ_num !r
and decr_num r = r := pred_num !r