module Random: sig .. end
Pseudo-random number generators (PRNG).
let init: int => unit;
Initialize the generator, using the argument as a seed. The same seed will always yield the same sequence of numbers.
let full_init: array(int) => unit;
Same as Random.init
but takes more data as seed.
let self_init: unit => unit;
Initialize the generator with a random seed chosen
in a system-dependent way. If /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).
let bits: unit => int;
Return 30 random bits in a nonnegative integer.
let 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.
let int32: Int32.t => Int32.t;
Random.int32 bound
returns a random integer between 0 (inclusive)
and bound
(exclusive). bound
must be greater than 0.
let nativeint: Nativeint.t => Nativeint.t;
Random.nativeint bound
returns a random integer between 0 (inclusive)
and bound
(exclusive). bound
must be greater than 0.
let int64: Int64.t => Int64.t;
Random.int64 bound
returns a random integer between 0 (inclusive)
and bound
(exclusive). bound
must be greater than 0.
let float: float => float;
Random.float bound
returns a random floating-point number
between 0 and bound
(inclusive). If bound
is
negative, the result is negative or zero. If bound
is 0,
the result is 0.
let bool: unit => bool;
Random.bool ()
returns true
or false
with probability 0.5 each.
The functions from module Random.State
manipulate the current state
of the random generator explicitly.
This allows using one or several deterministic PRNGs,
even in a multi-threaded program, without interference from
other parts of the program.
module State: sig .. end
let get_state: unit => State.t;
Return the current state of the generator used by the basic functions.
let set_state: State.t => unit;
Set the state of the generator used by the basic functions.