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  domain-local  generator, using the argument as a seed.
27       The same seed 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 domain-local generator with a random seed  chosen  in  a
40       system-dependent  way.   If  /dev/urandom  is available on the host ma‐
41       chine, it is used to provide a highly random initial seed.   Otherwise,
42       a  less  random  seed is computed from system parameters (current time,
43       process IDs, domain-local state).
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47       val bits : unit -> int
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49       Return 30 random bits in a nonnegative integer.
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52       Before5.0.0 used a different algorithm (affects all the following func‐
53       tions)
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58       val int : int -> int
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61       Random.int  bound  returns  a  random integer between 0 (inclusive) and
62       bound (exclusive).  bound must be greater than 0 and less than 2^30.
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66       val full_int : int -> int
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69       Random.full_int bound returns a random integer  between  0  (inclusive)
70       and bound (exclusive).  bound may be any positive integer.
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72       If  bound  is  less  than  2^30, Random.full_int bound is equal to Ran‐
73       dom.int bound . If bound is greater than 2^30  (on  64-bit  systems  or
74       non-standard environments, such as JavaScript), Random.full_int returns
75       a value, where Random.int raises Invalid_argument .
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78       Since 4.13.0
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82       val int32 : Int32.t -> Int32.t
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85       Random.int32 bound returns a random integer between 0  (inclusive)  and
86       bound (exclusive).  bound must be greater than 0.
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90       val nativeint : Nativeint.t -> Nativeint.t
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93       Random.nativeint  bound  returns a random integer between 0 (inclusive)
94       and bound (exclusive).  bound must be greater than 0.
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98       val int64 : Int64.t -> Int64.t
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101       Random.int64 bound returns a random integer between 0  (inclusive)  and
102       bound (exclusive).  bound must be greater than 0.
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106       val float : float -> float
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109       Random.float bound returns a random floating-point number between 0 and
110       bound (inclusive).  If bound is negative, the  result  is  negative  or
111       zero.  If bound is 0, the result is 0.
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115       val bool : unit -> bool
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118       Random.bool () returns true or false with probability 0.5 each.
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122       val bits32 : unit -> Int32.t
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125       Random.bits32   ()  returns  32  random  bits  as  an  integer  between
126       Int32.min_int and Int32.max_int .
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129       Since 4.14.0
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133       val bits64 : unit -> Int64.t
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136       Random.bits64  ()  returns  64  random  bits  as  an  integer   between
137       Int64.min_int and Int64.max_int .
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140       Since 4.14.0
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144       val nativebits : unit -> Nativeint.t
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147       Random.nativebits () returns 32 or 64 random bits (depending on the bit
148       width of the platform) as an integer between Nativeint.min_int and  Na‐
149       tiveint.max_int .
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152       Since 4.14.0
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157   Advanced functions
158       The  functions from module Random.State manipulate the current state of
159       the random generator explicitly.  This allows using one or several  de‐
160       terministic  PRNGs, even in a multi-threaded program, without interfer‐
161       ence from other parts of the program.
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163       module State : sig end
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169       val get_state : unit -> State.t
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172       get_state() returns a fresh copy of the current state of the domain-lo‐
173       cal generator (which is used by the basic functions).
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177       val set_state : State.t -> unit
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180       set_state  s  updates  the  current state of the domain-local generator
181       (which is used by the basic functions) by copying the state s into it.
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185       val split : unit -> State.t
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187       Draw a fresh PRNG state from the current state of the domain-local gen‐
188       erator  used  by the default functions.  (The state of the domain-local
189       generator is modified.)  See Random.State.split .
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192       Since 5.0.0
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198OCamldoc                          2023-07-20                  Stdlib.Random(3)