1Stdlib.Random(3)                 OCaml library                Stdlib.Random(3)
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NAME

6       Stdlib.Random - no description
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Module

9       Module   Stdlib.Random
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Documentation

12       Module Random
13        : (module Stdlib__Random)
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23   Basic functions
24       val init : int -> unit
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26       Initialize  the generator, using the argument as a seed.  The same seed
27       will always yield the same sequence of numbers.
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31       val full_init : int array -> unit
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33       Same as Random.init but takes more data as seed.
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37       val self_init : unit -> unit
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39       Initialize the generator with a random seed chosen in  a  system-depen‐
40       dent way.  If /dev/urandom is available on the host machine, it is used
41       to provide a highly random initial seed.  Otherwise, a less random seed
42       is computed from system parameters (current time, process IDs).
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46       val bits : unit -> int
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48       Return 30 random bits in a nonnegative integer.
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51       Before3.12.0  used  a  different  algorithm  (affects all the following
52       functions)
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57       val int : int -> int
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60       Random.int bound returns a random integer  between  0  (inclusive)  and
61       bound (exclusive).  bound must be greater than 0 and less than 2^30.
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65       val full_int : int -> int
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68       Random.full_int  bound  returns  a random integer between 0 (inclusive)
69       and bound (exclusive).  bound may be any positive integer.
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71       If bound is less than 2^30, Random.full_int  bound  is  equal  to  Ran‐
72       dom.int  bound  .  If  bound is greater than 2^30 (on 64-bit systems or
73       non-standard environments, such as JavaScript), Random.full_int returns
74       a value, where Random.int raises Invalid_argument .
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77       Since 4.13.0
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81       val int32 : Int32.t -> Int32.t
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84       Random.int32  bound  returns a random integer between 0 (inclusive) and
85       bound (exclusive).  bound must be greater than 0.
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89       val nativeint : Nativeint.t -> Nativeint.t
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92       Random.nativeint bound returns a random integer between  0  (inclusive)
93       and bound (exclusive).  bound must be greater than 0.
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97       val int64 : Int64.t -> Int64.t
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100       Random.int64  bound  returns a random integer between 0 (inclusive) and
101       bound (exclusive).  bound must be greater than 0.
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105       val float : float -> float
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108       Random.float bound returns a random floating-point number between 0 and
109       bound  (inclusive).   If  bound  is negative, the result is negative or
110       zero.  If bound is 0, the result is 0.
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114       val bool : unit -> bool
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117       Random.bool () returns true or false with probability 0.5 each.
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122   Advanced functions
123       The functions from module Random.State manipulate the current state  of
124       the  random generator explicitly.  This allows using one or several de‐
125       terministic PRNGs, even in a multi-threaded program, without  interfer‐
126       ence from other parts of the program.
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128       module State : sig end
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134       val get_state : unit -> State.t
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136       Return the current state of the generator used by the basic functions.
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140       val set_state : State.t -> unit
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142       Set the state of the generator used by the basic functions.
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148OCamldoc                          2022-02-04                  Stdlib.Random(3)