.TH "Random" 3o source: 2019-01-25 OCamldoc "OCaml library"
.SH NAME
Random \- Pseudo-random number generators (PRNG).
.SH Module
Module   Random
.SH Documentation
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Module
.BI "Random"
 : 
.B sig  end

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Pseudo\-random number generators (PRNG)\&.

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.PP

.B === 
.B Basic functions
.B  ===

.PP

.I val init 
: 
.B int -> unit
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Initialize the generator, using the argument as a seed\&.
The same seed will always yield the same sequence of numbers\&.

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.I val full_init 
: 
.B int array -> unit
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Same as 
.B Random\&.init
but takes more data as seed\&.

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.I val self_init 
: 
.B unit -> unit
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Initialize the generator with a random seed chosen
in a system\-dependent way\&.  If 
.B /dev/urandom
is available on
the host machine, it is used to provide a highly random initial
seed\&.  Otherwise, a less random seed is computed from system
parameters (current time, process IDs)\&.

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.I val bits 
: 
.B unit -> int
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Return 30 random bits in a nonnegative integer\&.

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.B "Before3.12.0"
used a different algorithm (affects all the following
functions)


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.I val int 
: 
.B int -> int
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.B Random\&.int bound
returns a random integer between 0 (inclusive)
and 
.B bound
(exclusive)\&.  
.B bound
must be greater than 0 and less
than 2^{30\&.

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.I val int32 
: 
.B Int32.t -> Int32.t
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.B Random\&.int32 bound
returns a random integer between 0 (inclusive)
and 
.B bound
(exclusive)\&.  
.B bound
must be greater than 0\&.

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.I val nativeint 
: 
.B Nativeint.t -> Nativeint.t
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.B Random\&.nativeint bound
returns a random integer between 0 (inclusive)
and 
.B bound
(exclusive)\&.  
.B bound
must be greater than 0\&.

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.I val int64 
: 
.B Int64.t -> Int64.t
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.B Random\&.int64 bound
returns a random integer between 0 (inclusive)
and 
.B bound
(exclusive)\&.  
.B bound
must be greater than 0\&.

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.I val float 
: 
.B float -> float
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.B Random\&.float bound
returns a random floating\-point number
between 0 and 
.B bound
(inclusive)\&.  If 
.B bound
is
negative, the result is negative or zero\&.  If 
.B bound
is 0,
the result is 0\&.

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.I val bool 
: 
.B unit -> bool
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.B Random\&.bool ()
returns 
.B true
or 
.B false
with probability 0\&.5 each\&.

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.PP

.B === 
.B Advanced functions
.B  ===

.PP

.PP

.B === The functions from module Random\&.State manipulate the current state
.B     of the random generator explicitly\&.
.B     This allows using one or several deterministic PRNGs,
.B     even in a multi\-threaded program, without interference from
.B     other parts of the program\&. ===

.PP
.I module State : 
.B sig  end

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.I val get_state 
: 
.B unit -> State.t
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Return the current state of the generator used by the basic functions\&.

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.I val set_state 
: 
.B State.t -> unit
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Set the state of the generator used by the basic functions\&.

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