Huge News!Announcing our $40M Series B led by Abstract Ventures.Learn More
Socket
Sign inDemoInstall
Socket

@stdlib/random-base-minstd-shuffle

Package Overview
Dependencies
Maintainers
4
Versions
9
Alerts
File Explorer

Advanced tools

Socket logo

Install Socket

Detect and block malicious and high-risk dependencies

Install

@stdlib/random-base-minstd-shuffle

A linear congruential pseudorandom number generator (LCG) whose output is shuffled.

  • 0.2.1
  • latest
  • Source
  • npm
  • Socket score

Version published
Weekly downloads
17K
increased by105.78%
Maintainers
4
Weekly downloads
 
Created
Source
About stdlib...

We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.

The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.

When you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.

To join us in bringing numerical computing to the web, get started by checking us out on GitHub, and please consider financially supporting stdlib. We greatly appreciate your continued support!

MINSTD Shuffle

NPM version Build Status Coverage Status

A linear congruential pseudorandom number generator (LCG) whose output is shuffled.

Installation

npm install @stdlib/random-base-minstd-shuffle

Usage

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

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

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

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

var v = minstd.normalized();
// returns <number>
minstd.factory( [options] )

Returns a linear congruential pseudorandom number generator (LCG) whose output is shuffled.

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 v = rand();
// returns 1421600654

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-shuffle'
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 v;
var i;

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

// Generate the same pseudorandom values...
rand = minstd.factory({
    'seed': minstd.seed
});
for ( i = 0; i < 100; i++ ) {
    v = 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 a copy of 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': [] }

Notes

  • Before output from a simple linear congruential generator (LCG) is returned, the output is shuffled using the Bays-Durham algorithm. This additional step considerably strengthens the "randomness quality" of a simple LCG's output.
  • The generator has a period of approximately 2.1e9 (see Numerical Recipes in C, 2nd Edition, p. 279).
  • An LCG is fast and uses little memory. On the other hand, because the generator is a simple linear congruential generator, the generator has recognized shortcomings. By today's PRNG standards, the generator's period is relatively short. In general, this generator is unsuitable for Monte Carlo simulations and cryptographic applications.
  • If PRNG state is "shared" (meaning a state array was provided during PRNG creation and not copied) and one sets the generator state to a state array having a different length, the PRNG does not update the existing shared state and, instead, points to the newly provided state array. In order to synchronize PRNG output according to the new shared state array, the state array for each relevant PRNG must be explicitly set.
  • If PRNG state is "shared" and one sets the generator state to a state array of the same length, the PRNG state is updated (along with the state of all other PRNGs sharing the PRNG's state array).

Examples

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

var seed;
var rand;
var i;

// Generate pseudorandom numbers...
for ( i = 0; i < 100; i++ ) {
    console.log( minstd() );
}

// Create a new pseudorandom number generator...
seed = 1234;
rand = minstd.factory({
    'seed': seed
});
for ( i = 0; i < 100; i++ ) {
    console.log( rand() );
}

// Create another pseudorandom number generator using a previous seed...
rand = minstd.factory({
    'seed': minstd.seed
});
for ( i = 0; i < 100; i++ ) {
    console.log( rand() );
}

References

  • Park, S. K., and K. W. Miller. 1988. "Random Number Generators: Good Ones Are Hard to Find." Communications of the ACM 31 (10). New York, NY, USA: ACM: 1192–1201. doi:10.1145/63039.63042.
  • Bays, Carter, and S. D. Durham. 1976. "Improving a Poor Random Number Generator." ACM Transactions on Mathematical Software 2 (1). New York, NY, USA: ACM: 59–64. doi:10.1145/355666.355670.
  • Herzog, T.N., and G. Lord. 2002. Applications of Monte Carlo Methods to Finance and Insurance. ACTEX Publications. https://books.google.com/books?id=vC7I\_gdX-A0C.
  • Press, William H., Brian P. Flannery, Saul A. Teukolsky, and William T. Vetterling. 1992. Numerical Recipes in C: The Art of Scientific Computing, Second Edition. Cambridge University Press.

See Also


Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

Chat


License

See LICENSE.

Copyright © 2016-2024. The Stdlib Authors.

Keywords

FAQs

Package last updated on 25 Feb 2024

Did you know?

Socket

Socket for GitHub automatically highlights issues in each pull request and monitors the health of all your open source dependencies. Discover the contents of your packages and block harmful activity before you install or update your dependencies.

Install

Related posts

SocketSocket SOC 2 Logo

Product

  • Package Alerts
  • Integrations
  • Docs
  • Pricing
  • FAQ
  • Roadmap
  • Changelog

Packages

npm

Stay in touch

Get open source security insights delivered straight into your inbox.


  • Terms
  • Privacy
  • Security

Made with ⚡️ by Socket Inc