MINSTD

Usage

var minstd = require( '@stdlib/random/base/minstd' );

minstd()

Returns a pseudorandom integer on the interval [1, 2147483646].

var r = minstd();
// returns <number>

minstd.normalized()

Returns a pseudorandom number on the interval [0,1).

var r = minstd.normalized();
// returns <number>

minstd.factory( [options] )

Returns a linear congruential pseudorandom number generator (LCG).

var rand = minstd.factory();

The function accepts the following options:

• seed: pseudorandom number generator seed.
• state: an Int32Array containing pseudorandom number generator state. If provided, the function ignores the seed option.
• copy: boolean indicating whether to copy a provided pseudorandom number generator state. Setting this option to false allows sharing state between two or more pseudorandom number generators. Setting this option to true ensures that a returned generator has exclusive control over its internal state. Default: true.

By default, a random integer is used to seed the returned generator. To seed the generator, provide either an integer on the interval [1, 2147483646]

var rand = minstd.factory({
    'seed': 1234
});

var r = rand();
// returns 20739838

or, for arbitrary length seeds, an array-like object containing signed 32-bit integers

var Int32Array = require( '@stdlib/array/int32' );

var rand = minstd.factory({
    'seed': new Int32Array( [ 1234 ] )
});

var r = rand();
// returns 20739838

To return a generator having a specific initial state, set the generator state option.

var rand;
var bool;
var r;
var i;

// Generate pseudorandom numbers, thus progressing the generator state:
for ( i = 0; i < 1000; i++ ) {
    r = minstd();
}

// Create a new PRNG initialized to the current state of `minstd`:
rand = minstd.factory({
    'state': minstd.state
});

// Test that the generated pseudorandom numbers are the same:
bool = ( rand() === minstd() );
// returns true

minstd.NAME

The generator name.

var str = minstd.NAME;
// returns 'minstd'

minstd.MIN

Minimum possible value.

var min = minstd.MIN;
// returns 1

minstd.MAX

Maximum possible value.

var max = minstd.MAX;
// returns 2147483646

minstd.seed

The value used to seed minstd().

var rand;
var r;
var i;

// Generate pseudorandom values...
for ( i = 0; i < 100; i++ ) {
    r = minstd();
}

// Generate the same pseudorandom values...
rand = minstd.factory({
    'seed': minstd.seed
});
for ( i = 0; i < 100; i++ ) {
    r = rand();
}

minstd.seedLength

Length of generator seed.

var len = minstd.seedLength;
// returns <number>

minstd.state

Writable property for getting and setting the generator state.

var r = minstd();
// returns <number>

r = minstd();
// returns <number>

// ...

// Get the current state:
var state = minstd.state;
// returns <Int32Array>

r = minstd();
// returns <number>

r = minstd();
// returns <number>

// Reset the state:
minstd.state = state;

// Replay the last two pseudorandom numbers:
r = minstd();
// returns <number>

r = minstd();
// returns <number>

// ...

minstd.stateLength

Length of generator state.

var len = minstd.stateLength;
// returns <number>

minstd.byteLength

Size (in bytes) of generator state.

var sz = minstd.byteLength;
// returns <number>

minstd.toJSON()

Serializes the pseudorandom number generator as a JSON object.

var o = minstd.toJSON();
// returns { 'type': 'PRNG', 'name': '...', 'state': {...}, 'params': [] }