batteries 2.11.0 · OCaml Package

batteries

Pseudo-random number generators (PRNG).

This module extends Stdlib's Random module, go there for documentation on the rest of the functions and types.

author Damien Doligez (base library)

author David Teller

author Pierre Chambart

@documents Random

Basic functions

val init : int -> unit

Initialize the generator, using the argument as a seed. The same seed will always yield the same sequence of numbers.

val full_init : int array -> unit

Same as Random.init but takes more data as seed.

val self_init : unit -> unit

Initialize the generator with a more-or-less random seed chosen in a system-dependent way.

val bits : unit -> int

Return 30 random bits in a nonnegative integer.

val int : int -> int

Random.int bound returns a random integer between 0 (inclusive) and bound (exclusive). bound must be greater than 0 and less than 2³⁰.

val int32 : Int32.t -> Int32.t

val nativeint : Nativeint.t -> Nativeint.t

val int64 : Int64.t -> Int64.t

Random.nativeint bound returns a random integer between 0 (inclusive) and bound (exclusive). bound must be greater than 0.

val float : float -> float

Random.float bound returns a random floating-point number between 0 (inclusive) and bound (exclusive). If bound is negative, the result is negative or zero. If bound is 0, the result is 0.

val bool : unit -> bool

Random.bool () returns true or false with probability 0.5 each.

val char : unit -> char

Return a random Latin-1 character.

val full_range_int : unit -> int

full_range_int () returns the maximum entropy possible in a single int: 31 bits on 32-bit platforms and 63 bits on 64-bit platforms. Intentionally gives different results on different platforms, so is not portable.

Enumerations of random values.

val enum_bits : unit -> int BatEnum.t

val enum_int : int -> int BatEnum.t

val enum_bool : unit -> bool BatEnum.t

val enum_float : float -> float BatEnum.t

val enum_int32 : Int32.t -> Int32.t BatEnum.t

val enum_int64 : Int64.t -> Int64.t BatEnum.t

val enum_nativeint : Nativeint.t -> Nativeint.t BatEnum.t

val enum_char : unit -> char BatEnum.t

Working with data structures.

val choice : 'a BatEnum.t -> 'a

choice e returns a randomly-chosen element of e.

This function only works on finite enumerations with less than 2³⁰ elements.

val multi_choice : int -> 'a BatEnum.t -> 'a BatEnum.t

multi_choice n e returns an enumeration of n randomly-chosen elements of e.

val shuffle : 'a BatEnum.t -> 'a array

shuffle e returns a new array, containing the same set of elements as e, but in a random order.

Shuffling is implemented using the Fisher-Yates algorithm and works in O(n), where n is the number of elements of e.

This function only works on finite enumerations with less than 2³⁰ elements.

Advanced functions

module State : sig ... end

Manipulate the current state of the random generator.

val get_state : unit -> State.t

Return the current state of the generator used by the basic functions.

val set_state : State.t -> unit

Set the state of the generator used by the basic functions.

module Incubator : sig ... end

package batteries

Basic functions

Enumerations of random values.

Working with data structures.

Advanced functions