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(**************************************************************************)
(*                                                                        *)
(*                                 OCaml                                  *)
(*                                                                        *)
(*             Xavier Leroy, projet Cristal, INRIA Rocquencourt           *)
(*                        Nicolas Ojeda Bar, LexiFi                       *)
(*                                                                        *)
(*   Copyright 2018 Institut National de Recherche en Informatique et     *)
(*     en Automatique.                                                    *)
(*                                                                        *)
(*   All rights reserved.  This file is distributed under the terms of    *)
(*   the GNU Lesser General Public License version 2.1, with the          *)
(*   special exception on linking described in the file LICENSE.          *)
(*                                                                        *)
(**************************************************************************)

(** {1 Floating-point arithmetic}

    OCaml's floating-point numbers follow the
    IEEE 754 standard, using double precision (64 bits) numbers.
    Floating-point operations never raise an exception on overflow,
    underflow, division by zero, etc.  Instead, special IEEE numbers
    are returned as appropriate, such as [infinity] for [1.0 /. 0.0],
    [neg_infinity] for [-1.0 /. 0.0], and [nan] ('not a number')
    for [0.0 /. 0.0].  These special numbers then propagate through
    floating-point computations as expected: for instance,
    [1.0 /. infinity] is [0.0], and any arithmetic operation with [nan]
    as argument returns [nan] as result.

    @since 4.07.0
*)

val zero : float
(** The floating point 0.
   @since 4.08.0 *)

val one : float
(** The floating-point 1.
   @since 4.08.0 *)

val minus_one : float
(** The floating-point -1.
   @since 4.08.0 *)

external neg : float -> float = "%negfloat"
(** Unary negation. *)

external add : float -> float -> float = "%addfloat"
(** Floating-point addition. *)

external sub : float -> float -> float = "%subfloat"
(** Floating-point subtraction. *)

external mul : float -> float -> float = "%mulfloat"
(** Floating-point multiplication. *)

external div : float -> float -> float = "%divfloat"
(** Floating-point division. *)

external fma : float -> float -> float -> float =
  "caml_fma_float" "caml_fma" [@@unboxed] [@@noalloc]
(** [fma x y z] returns [x * y + z], with a best effort for computing
   this expression with a single rounding, using either hardware
   instructions (providing full IEEE compliance) or a software
   emulation.  Note: since software emulation of the fma is costly,
   make sure that you are using hardware fma support if performance
   matters.  @since 4.08.0 *)

external rem : float -> float -> float = "caml_fmod_float" "fmod"
[@@unboxed] [@@noalloc]
(** [rem a b] returns the remainder of [a] with respect to [b].  The returned
    value is [a -. n *. b], where [n] is the quotient [a /. b] rounded towards
    zero to an integer. *)

val succ : float -> float
(** [succ x] returns the floating point number right after [x] i.e.,
   the smallest floating-point number greater than [x].  See also
   {!next_after}.
   @since 4.08.0 *)

val pred : float -> float
(** [pred x] returns the floating-point number right before [x] i.e.,
   the greatest floating-point number smaller than [x].  See also
   {!next_after}.
   @since 4.08.0 *)

external abs : float -> float = "%absfloat"
(** [abs f] returns the absolute value of [f]. *)

val infinity : float
(** Positive infinity. *)

val neg_infinity : float
(** Negative infinity. *)

val nan : float
(** A special floating-point value denoting the result of an
    undefined operation such as [0.0 /. 0.0].  Stands for
    'not a number'.  Any floating-point operation with [nan] as
    argument returns [nan] as result.  As for floating-point comparisons,
    [=], [<], [<=], [>] and [>=] return [false] and [<>] returns [true]
    if one or both of their arguments is [nan]. *)

val pi : float
(** The constant pi. *)

val max_float : float
(** The largest positive finite value of type [float]. *)

val min_float : float
(** The smallest positive, non-zero, non-denormalized value of type [float]. *)

val epsilon : float
(** The difference between [1.0] and the smallest exactly representable
    floating-point number greater than [1.0]. *)

val is_finite : float -> bool
(** [is_finite x] is [true] iff [x] is finite i.e., not infinite and
   not {!nan}.

   @since 4.08.0 *)

val is_infinite : float -> bool
(** [is_infinite x] is [true] iff [x] is {!infinity} or {!neg_infinity}.

   @since 4.08.0 *)

val is_nan : float -> bool
(** [is_nan x] is [true] iff [x] is not a number (see {!nan}).

   @since 4.08.0 *)

val is_integer : float -> bool
(** [is_integer x] is [true] iff [x] is an integer.

   @since 4.08.0 *)

external of_int : int -> float = "%floatofint"
(** Convert an integer to floating-point. *)

external to_int : float -> int = "%intoffloat"
(** Truncate the given floating-point number to an integer.
    The result is unspecified if the argument is [nan] or falls outside the
    range of representable integers. *)

external of_string : string -> float = "caml_float_of_string"
(** Convert the given string to a float.  The string is read in decimal
    (by default) or in hexadecimal (marked by [0x] or [0X]).
    The format of decimal floating-point numbers is
    [ [-] dd.ddd (e|E) [+|-] dd ], where [d] stands for a decimal digit.
    The format of hexadecimal floating-point numbers is
    [ [-] 0(x|X) hh.hhh (p|P) [+|-] dd ], where [h] stands for an
    hexadecimal digit and [d] for a decimal digit.
    In both cases, at least one of the integer and fractional parts must be
    given; the exponent part is optional.
    The [_] (underscore) character can appear anywhere in the string
    and is ignored.
    Depending on the execution platforms, other representations of
    floating-point numbers can be accepted, but should not be relied upon.
    Raise [Failure "float_of_string"] if the given string is not a valid
    representation of a float. *)

val of_string_opt: string -> float option
(** Same as [of_string], but returns [None] instead of raising. *)

val to_string : float -> string
(** Return the string representation of a floating-point number. *)

type fpclass = Stdlib.fpclass =
    FP_normal           (** Normal number, none of the below *)
  | FP_subnormal        (** Number very close to 0.0, has reduced precision *)
  | FP_zero             (** Number is 0.0 or -0.0 *)
  | FP_infinite         (** Number is positive or negative infinity *)
  | FP_nan              (** Not a number: result of an undefined operation *)
(** The five classes of floating-point numbers, as determined by
    the {!classify_float} function. *)

external classify_float : (float [@unboxed]) -> fpclass =
  "caml_classify_float" "caml_classify_float_unboxed" [@@noalloc]
(** Return the class of the given floating-point number:
    normal, subnormal, zero, infinite, or not a number. *)

external pow : float -> float -> float = "caml_power_float" "pow"
[@@unboxed] [@@noalloc]
(** Exponentiation. *)

external sqrt : float -> float = "caml_sqrt_float" "sqrt"
[@@unboxed] [@@noalloc]
(** Square root. *)

external exp : float -> float = "caml_exp_float" "exp" [@@unboxed] [@@noalloc]
(** Exponential. *)

external log : float -> float = "caml_log_float" "log" [@@unboxed] [@@noalloc]
(** Natural logarithm. *)

external log10 : float -> float = "caml_log10_float" "log10"
[@@unboxed] [@@noalloc]
(** Base 10 logarithm. *)

external expm1 : float -> float = "caml_expm1_float" "caml_expm1"
[@@unboxed] [@@noalloc]
(** [expm1 x] computes [exp x -. 1.0], giving numerically-accurate results
    even if [x] is close to [0.0]. *)

external log1p : float -> float = "caml_log1p_float" "caml_log1p"
[@@unboxed] [@@noalloc]
(** [log1p x] computes [log(1.0 +. x)] (natural logarithm),
    giving numerically-accurate results even if [x] is close to [0.0]. *)

external cos : float -> float = "caml_cos_float" "cos" [@@unboxed] [@@noalloc]
(** Cosine.  Argument is in radians. *)

external sin : float -> float = "caml_sin_float" "sin" [@@unboxed] [@@noalloc]
(** Sine.  Argument is in radians. *)

external tan : float -> float = "caml_tan_float" "tan" [@@unboxed] [@@noalloc]
(** Tangent.  Argument is in radians. *)

external acos : float -> float = "caml_acos_float" "acos"
[@@unboxed] [@@noalloc]
(** Arc cosine.  The argument must fall within the range [[-1.0, 1.0]].
    Result is in radians and is between [0.0] and [pi]. *)

external asin : float -> float = "caml_asin_float" "asin"
[@@unboxed] [@@noalloc]
(** Arc sine.  The argument must fall within the range [[-1.0, 1.0]].
    Result is in radians and is between [-pi/2] and [pi/2]. *)

external atan : float -> float = "caml_atan_float" "atan"
[@@unboxed] [@@noalloc]
(** Arc tangent.
    Result is in radians and is between [-pi/2] and [pi/2]. *)

external atan2 : float -> float -> float = "caml_atan2_float" "atan2"
[@@unboxed] [@@noalloc]
(** [atan2 y x] returns the arc tangent of [y /. x].  The signs of [x]
    and [y] are used to determine the quadrant of the result.
    Result is in radians and is between [-pi] and [pi]. *)

external hypot : float -> float -> float = "caml_hypot_float" "caml_hypot"
[@@unboxed] [@@noalloc]
(** [hypot x y] returns [sqrt(x *. x + y *. y)], that is, the length
    of the hypotenuse of a right-angled triangle with sides of length
    [x] and [y], or, equivalently, the distance of the point [(x,y)]
    to origin.  If one of [x] or [y] is infinite, returns [infinity]
    even if the other is [nan]. *)

external cosh : float -> float = "caml_cosh_float" "cosh"
[@@unboxed] [@@noalloc]
(** Hyperbolic cosine.  Argument is in radians. *)

external sinh : float -> float = "caml_sinh_float" "sinh"
[@@unboxed] [@@noalloc]
(** Hyperbolic sine.  Argument is in radians. *)

external tanh : float -> float = "caml_tanh_float" "tanh"
[@@unboxed] [@@noalloc]
(** Hyperbolic tangent.  Argument is in radians. *)

external trunc : float -> float = "caml_trunc_float" "caml_trunc"
                                    [@@unboxed] [@@noalloc]
(** [trunc x] rounds [x] to the nearest integer whose absolute value is
   less than or equal to [x].

   @since 4.08.0 *)

external round : float -> float = "caml_round_float" "caml_round"
                                    [@@unboxed] [@@noalloc]
(** [round x] rounds [x] to the nearest integer with ties (fractional
   values of 0.5) rounded away from zero, regardless of the current
   rounding direction.  If [x] is an integer, [+0.], [-0.], [nan], or
   infinite, [x] itself is returned.

   @since 4.08.0 *)

external ceil : float -> float = "caml_ceil_float" "ceil"
[@@unboxed] [@@noalloc]
(** Round above to an integer value.
    [ceil f] returns the least integer value greater than or equal to [f].
    The result is returned as a float. *)

external floor : float -> float = "caml_floor_float" "floor"
[@@unboxed] [@@noalloc]
(** Round below to an integer value.
    [floor f] returns the greatest integer value less than or
    equal to [f].
    The result is returned as a float. *)

external next_after : float -> float -> float
  = "caml_nextafter_float" "caml_nextafter" [@@unboxed] [@@noalloc]
(** [next_after x y] returns the next representable floating-point
   value following [x] in the direction of [y].  More precisely, if
   [y] is greater (resp. less) than [x], it returns the smallest
   (resp. largest) representable number greater (resp. less) than [x].
   If [x] equals [y], the function returns [y].  If [x] or [y] is
   [nan], a [nan] is returned.
   Note that [next_after max_float infinity = infinity] and that
   [next_after 0. infinity] is the smallest denormalized positive number.
   If [x] is the smallest denormalized positive number,
   [next_after x 0. = 0.]

   @since 4.08.0 *)

external copy_sign : float -> float -> float
  = "caml_copysign_float" "caml_copysign"
[@@unboxed] [@@noalloc]
(** [copy_sign x y] returns a float whose absolute value is that of [x]
    and whose sign is that of [y].  If [x] is [nan], returns [nan].
    If [y] is [nan], returns either [x] or [-. x], but it is not
    specified which. *)

external sign_bit : (float [@unboxed]) -> bool
  = "caml_signbit_float" "caml_signbit" [@@noalloc]
(** [sign_bit x] is [true] iff the sign bit of [x] is set.
    For example [sign_bit 1.] and [signbit 0.] are [false] while
    [sign_bit (-1.)] and [sign_bit (-0.)] are [true].

    @since 4.08.0 *)

external frexp : float -> float * int = "caml_frexp_float"
(** [frexp f] returns the pair of the significant
    and the exponent of [f].  When [f] is zero, the
    significant [x] and the exponent [n] of [f] are equal to
    zero.  When [f] is non-zero, they are defined by
    [f = x *. 2 ** n] and [0.5 <= x < 1.0]. *)

external ldexp : (float [@unboxed]) -> (int [@untagged]) -> (float [@unboxed]) =
  "caml_ldexp_float" "caml_ldexp_float_unboxed" [@@noalloc]
(** [ldexp x n] returns [x *. 2 ** n]. *)

external modf : float -> float * float = "caml_modf_float"
(** [modf f] returns the pair of the fractional and integral
    part of [f]. *)

type t = float
(** An alias for the type of floating-point numbers. *)

val compare: t -> t -> int
(** [compare x y] returns [0] if [x] is equal to [y], a negative integer if [x]
    is less than [y], and a positive integer if [x] is greater than
    [y]. [compare] treats [nan] as equal to itself and less than any other float
    value.  This treatment of [nan] ensures that [compare] defines a total
    ordering relation.  *)

val equal: t -> t -> bool
(** The equal function for floating-point numbers, compared using {!compare}. *)

val min : t -> t -> t
(** [min x y] returns the minimum of [x] and [y].  It returns [nan]
   when [x] or [y] is [nan].  Moreover [min (-0.) (+0.) = -0.]

   @since 4.08.0 *)

val max : float -> float -> float
(** [max x y] returns the maximum of [x] and [y].  It returns [nan]
   when [x] or [y] is [nan].  Moreover [max (-0.) (+0.) = +0.]

   @since 4.08.0 *)

val min_max : float -> float -> float * float
(** [min_max x y] is [(min x y, max x y)], just more efficient.

   @since 4.08.0 *)

val min_num : t -> t -> t
(** [min_num x y] returns the minimum of [x] and [y] treating [nan] as
   missing values.  If both [x] and [y] are [nan], [nan] is returned.
   Moreover [min_num (-0.) (+0.) = -0.]

   @since 4.08.0 *)

val max_num : t -> t -> t
(** [max_num x y] returns the maximum of [x] and [y] treating [nan] as
   missing values.  If both [x] and [y] are [nan] [nan] is returned.
   Moreover [max_num (-0.) (+0.) = +0.]

   @since 4.08.0 *)

val min_max_num : float -> float -> float * float
(** [min_max_num x y] is [(min_num x y, max_num x y)], just more
   efficient.  Note that in particular [min_max_num x nan = (x, x)]
   and [min_max_num nan y = (y, y)].

   @since 4.08.0 *)


val hash: t -> int
(** The hash function for floating-point numbers. *)

module Array : sig

  type t = floatarray
  (** The type of float arrays with packed representation.  @since 4.08.0 *)

  val length : t -> int
  (** Return the length (number of elements) of the given floatarray. *)

  val get : t -> int -> float
  (** [get a n] returns the element number [n] of floatarray [a].

      Raise [Invalid_argument] if [n] is outside the range 0 to
      [(length a - 1)]. *)

  val set : t -> int -> float -> unit
  (** [set a n x] modifies floatarray [a] in place, replacing element
      number [n] with [x].

      Raise [Invalid_argument] if [n] is outside the range 0 to
      [(length a - 1)]. *)

  val make : int -> float -> t
  (** [make n x] returns a fresh floatarray of length [n], initialized with [x].

      Raise [Invalid_argument] if [n < 0] or [n > Sys.max_floatarray_length]. *)

  val create : int -> t
  (** [create n] returns a fresh floatarray of length [n],
      with uninitialized data.

      Raise [Invalid_argument] if [n < 0] or [n > Sys.max_floatarray_length]. *)

  val init : int -> (int -> float) -> t
  (** [init n f] returns a fresh floatarray of length [n],
     with element number [i] initialized to the result of [f i].
     In other terms, [init n f] tabulates the results of [f]
     applied to the integers [0] to [n-1].

     Raise [Invalid_argument] if [n < 0] or [n > Sys.max_floatarray_length]. *)

  val append : t -> t -> t
  (** [append v1 v2] returns a fresh floatarray containing the
     concatenation of the floatarrays [v1] and [v2].

     Raise [Invalid_argument] if
     [length v1 + length v2 > Sys.max_floatarray_length]. *)

  val concat : t list -> t
  (** Same as {!append}, but concatenates a list of floatarrays. *)

  val sub : t -> int -> int -> t
  (** [sub a start len] returns a fresh floatarray of length [len],
     containing the elements number [start] to [start + len - 1]
     of floatarray [a].

     Raise [Invalid_argument] if [start] and [len] do not
     designate a valid subarray of [a]; that is, if
     [start < 0], or [len < 0], or [start + len > length a]. *)

  val copy : t -> t
  (** [copy a] returns a copy of [a], that is, a fresh floatarray
      containing the same elements as [a]. *)

  val fill : t -> int -> int -> float -> unit
  (** [fill a ofs len x] modifies the floatarray [a] in place,
     storing [x] in elements number [ofs] to [ofs + len - 1].

     Raise [Invalid_argument] if [ofs] and [len] do not
     designate a valid subarray of [a]. *)

  val blit : t -> int -> t -> int -> int -> unit
  (** [blit v1 o1 v2 o2 len] copies [len] elements
      from floatarray [v1], starting at element number [o1], to floatarray [v2],
      starting at element number [o2]. It works correctly even if
      [v1] and [v2] are the same floatarray, and the source and
      destination chunks overlap.

      Raise [Invalid_argument] if [o1] and [len] do not
      designate a valid subarray of [v1], or if [o2] and [len] do not
      designate a valid subarray of [v2]. *)

  val to_list : t -> float list
  (** [to_list a] returns the list of all the elements of [a]. *)

  val of_list : float list -> t
  (** [of_list l] returns a fresh floatarray containing the elements
      of [l].

      Raise [Invalid_argument] if the length of [l] is greater than
      [Sys.max_floatarray_length].*)

  (** {2 Iterators} *)

  val iter : (float -> unit) -> t -> unit
  (** [iter f a] applies function [f] in turn to all
      the elements of [a].  It is equivalent to
      [f a.(0); f a.(1); ...; f a.(length a - 1); ()]. *)

  val iteri : (int -> float -> unit) -> t -> unit
  (** Same as {!iter}, but the
      function is applied with the index of the element as first argument,
      and the element itself as second argument. *)

  val map : (float -> float) -> t -> t
  (** [map f a] applies function [f] to all the elements of [a],
      and builds a floatarray with the results returned by [f]. *)

  val mapi : (int -> float -> float) -> t -> t
  (** Same as {!map}, but the
      function is applied to the index of the element as first argument,
      and the element itself as second argument. *)

  val fold_left : ('a -> float -> 'a) -> 'a -> t -> 'a
  (** [fold_left f x a] computes
      [f (... (f (f x a.(0)) a.(1)) ...) a.(n-1)],
      where [n] is the length of the floatarray [a]. *)

  val fold_right : (float -> 'a -> 'a) -> t -> 'a -> 'a
  (** [fold_right f a x] computes
      [f a.(0) (f a.(1) ( ... (f a.(n-1) x) ...))],
      where [n] is the length of the floatarray [a]. *)

  (** {2 Iterators on two arrays} *)

  val iter2 : (float -> float -> unit) -> t -> t -> unit
  (** [Array.iter2 f a b] applies function [f] to all the elements of [a]
      and [b].
      Raise [Invalid_argument] if the floatarrays are not the same size. *)

  val map2 : (float -> float -> float) -> t -> t -> t
  (** [map2 f a b] applies function [f] to all the elements of [a]
      and [b], and builds a floatarray with the results returned by [f]:
      [[| f a.(0) b.(0); ...; f a.(length a - 1) b.(length b - 1)|]].
      Raise [Invalid_argument] if the floatarrays are not the same size. *)

  (** {2 Array scanning} *)

  val for_all : (float -> bool) -> t -> bool
  (** [for_all p [|a1; ...; an|]] checks if all elements of the floatarray
      satisfy the predicate [p]. That is, it returns
      [(p a1) && (p a2) && ... && (p an)]. *)

  val exists : (float -> bool) -> t -> bool
  (** [exists p [|a1; ...; an|]] checks if at least one element of
      the floatarray satisfies the predicate [p]. That is, it returns
      [(p a1) || (p a2) || ... || (p an)]. *)

  val mem : float -> t -> bool
  (** [mem a l] is true if and only if there is an element of [l] that is
      structurally equal to [a], i.e. there is an [x] in [l] such
      that [compare a x = 0]. *)

  val mem_ieee : float -> t -> bool
  (** Same as {!mem}, but uses IEEE equality instead of structural equality. *)

  (** {2 Sorting} *)

  val sort : (float -> float -> int) -> t -> unit
  (** Sort a floatarray in increasing order according to a comparison
      function.  The comparison function must return 0 if its arguments
      compare as equal, a positive integer if the first is greater,
      and a negative integer if the first is smaller (see below for a
      complete specification).  For example, {!Stdlib.compare} is
      a suitable comparison function.  After calling [sort], the
      array is sorted in place in increasing order.
      [sort] is guaranteed to run in constant heap space
      and (at most) logarithmic stack space.

      The current implementation uses Heap Sort.  It runs in constant
      stack space.

      Specification of the comparison function:
      Let [a] be the floatarray and [cmp] the comparison function. The following
      must be true for all [x], [y], [z] in [a] :
-      [cmp x y] > 0 if and only if [cmp y x] < 0
-      if [cmp x y] >= 0 and [cmp y z] >= 0 then [cmp x z] >= 0

      When [sort] returns, [a] contains the same elements as before,
      reordered in such a way that for all i and j valid indices of [a] :
-      [cmp a.(i) a.(j)] >= 0 if and only if i >= j
  *)

  val stable_sort : (float -> float -> int) -> t -> unit
  (** Same as {!sort}, but the sorting algorithm is stable (i.e.
       elements that compare equal are kept in their original order) and
       not guaranteed to run in constant heap space.

       The current implementation uses Merge Sort. It uses a temporary
       floatarray of length [n/2], where [n] is the length of the floatarray.
       It is usually faster than the current implementation of {!sort}. *)

  val fast_sort : (float -> float -> int) -> t -> unit
  (** Same as {!sort} or {!stable_sort}, whichever is faster
      on typical input. *)

  (** {2 Iterators} *)

  val to_seq : t -> float Seq.t
  (** Iterate on the floatarray, in increasing order. Modifications of the
      floatarray during iteration will be reflected in the iterator. *)

  val to_seqi : t -> (int * float) Seq.t
  (** Iterate on the floatarray, in increasing order, yielding indices along
      elements. Modifications of the floatarray during iteration will be
      reflected in the iterator. *)

  val of_seq : float Seq.t -> t
  (** Create an array from the generator. *)


  val map_to_array : (float -> 'a) -> t -> 'a array
  (** [map_to_array f a] applies function [f] to all the elements of [a],
      and builds an array with the results returned by [f]:
      [[| f a.(0); f a.(1); ...; f a.(length a - 1) |]]. *)

  val map_from_array : ('a -> float) -> 'a array -> t
  (** [map_from_array f a] applies function [f] to all the elements of [a],
      and builds a floatarray with the results returned by [f]. *)

  (** {2 Undocumented functions} *)

  (* These functions are for system use only. Do not call directly. *)
  external unsafe_get : t -> int -> float = "%floatarray_unsafe_get"
  external unsafe_set : t -> int -> float -> unit = "%floatarray_unsafe_set"
end

module ArrayLabels : sig

  type t = floatarray
  val length : t -> int
  val get : t -> int -> float
  val set : t -> int -> float -> unit
  val make : int -> float -> t
  val create : int -> t
  val init : int -> f:(int -> float) -> t
  val append : t -> t -> t
  val concat : t list -> t
  val sub : t -> pos:int -> len:int -> t
  val copy : t -> t
  val fill : t -> pos:int -> len:int -> float -> unit
  val blit : src:t -> src_pos:int -> dst:t -> dst_pos:int -> len:int -> unit
  val to_list : t -> float list
  val of_list : float list -> t
  val iter : f:(float -> unit) -> t -> unit
  val iteri : f:(int -> float -> unit) -> t -> unit
  val map : f:(float -> float) -> t -> t
  val mapi : f:(int -> float -> float) -> t -> t
  val fold_left : f:('a -> float -> 'a) -> init:'a -> t -> 'a
  val fold_right : f:(float -> 'a -> 'a) -> t -> init:'a -> 'a
  val iter2 : f:(float -> float -> unit) -> t -> t -> unit
  val map2 : f:(float -> float -> float) -> t -> t -> t
  val for_all : f:(float -> bool) -> t -> bool
  val exists : f:(float -> bool) -> t -> bool
  val mem : float -> set:t -> bool
  val mem_ieee : float -> set:t -> bool
  val sort : cmp:(float -> float -> int) -> t -> unit
  val stable_sort : cmp:(float -> float -> int) -> t -> unit
  val fast_sort : cmp:(float -> float -> int) -> t -> unit
  val to_seq : t -> float Seq.t
  val to_seqi : t -> (int * float) Seq.t
  val of_seq : float Seq.t -> t
  val map_to_array : f:(float -> 'a) -> t -> 'a array
  val map_from_array : f:('a -> float) -> 'a array -> t

  (* These functions are for system use only. Do not call directly. *)
  external unsafe_get : t -> int -> float = "%floatarray_unsafe_get"
  external unsafe_set : t -> int -> float -> unit = "%floatarray_unsafe_set"
end