Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/stdlib-js/random-strided-arcsine

Fill a strided array with arcsine distributed pseudorandom numbers.
https://github.com/stdlib-js/random-strided-arcsine

arcsine continuous generator javascript math mathematics node node-js nodejs prng pseudorandom rand random rng seed seedable statistics stats stdlib strided

Last synced: 4 days ago
JSON representation

Fill a strided array with arcsine distributed pseudorandom numbers.

Awesome Lists containing this project

README 

        



  

    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!



# Arcsine Random Numbers



[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] 



> Fill a strided array with pseudorandom numbers drawn from an [arcsine][@stdlib/random/base/arcsine] distribution.



## Installation



```bash

npm install @stdlib/random-strided-arcsine

```



Alternatively,



-   To load the package in a website via a `script` tag without installation and bundlers, use the [ES Module][es-module] available on the [`esm`][esm-url] branch (see [README][esm-readme]).

-   If you are using Deno, visit the [`deno`][deno-url] branch (see [README][deno-readme] for usage intructions).

-   For use in Observable, or in browser/node environments, use the [Universal Module Definition (UMD)][umd] build available on the [`umd`][umd-url] branch (see [README][umd-readme]).



The [branches.md][branches-url] file summarizes the available branches and displays a diagram illustrating their relationships.



To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.



## Usage



```javascript

var arcsine = require( '@stdlib/random-strided-arcsine' );

```



#### arcsine( N, a, sa, b, sb, out, so\[, options] )



Fills a strided array with pseudorandom numbers drawn from an [arcsine][@stdlib/random/base/arcsine] distribution.



```javascript

var Float64Array = require( '@stdlib/array-float64' );



// Create an array:

var out = new Float64Array( 10 );



// Fill the array with pseudorandom numbers:

arcsine( out.length, [ 2.0 ], 0, [ 5.0 ], 0, out, 1 );

```



The function has the following parameters:



-   **N**: number of indexed elements.

-   **a**: minimum support.

-   **sa**: index increment for `a`.

-   **b**: maximum support.

-   **sb**: index increment for `b`.

-   **out**: output array.

-   **so**: index increment for `out`.



The `N` and stride parameters determine which strided array elements are accessed at runtime. For example, to access every other value in `out`,



```javascript

var out = [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ];



arcsine( 3, [ 2.0 ], 0, [ 5.0 ], 0, out, 2 );

```



Note that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.



```javascript

var Float64Array = require( '@stdlib/array-float64' );



// Initial arrays...

var a0 = new Float64Array( [ 0.0, 0.0, 0.0, 2.0, 2.0, 2.0 ] );

var b0 = new Float64Array( [ 5.0, 5.0, 5.0, 5.0, 5.0, 5.0 ] );



// Create offset views...

var a1 = new Float64Array( a0.buffer, a0.BYTES_PER_ELEMENT*1 ); // start at 2nd element

var b1 = new Float64Array( b0.buffer, b0.BYTES_PER_ELEMENT*3 ); // start at 4th element



// Create an output array:

var out = new Float64Array( 3 );



// Fill the output array:

arcsine( out.length, a1, -2, b1, 1, out, 1 );

```



The function accepts the following `options`:



-   **prng**: pseudorandom number generator for generating uniformly distributed pseudorandom numbers on the interval `[0,1)`. If provided, the function **ignores** both the `state` and `seed` options. In order to seed the underlying pseudorandom number generator, one must seed the provided `prng` (assuming the provided `prng` is seedable).

-   **seed**: pseudorandom number generator seed.

-   **state**: a [`Uint32Array`][@stdlib/array/uint32] 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 an underlying generator has exclusive control over its internal state. Default: `true`.



To use a custom PRNG as the underlying source of uniformly distributed pseudorandom numbers, set the `prng` option.



```javascript

var Float64Array = require( '@stdlib/array-float64' );

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



var opts = {

    'prng': minstd.normalized

};



var out = new Float64Array( 10 );

arcsine( out.length, [ 2.0 ], 0, [ 5.0 ], 0, out, 1, opts );

```



To seed the underlying pseudorandom number generator, set the `seed` option.



```javascript

var Float64Array = require( '@stdlib/array-float64' );



var opts = {

    'seed': 12345

};



var out = new Float64Array( 10 );

arcsine( out.length, [ 2.0 ], 0, [ 5.0 ], 0, out, 1, opts );

```



#### arcsine.ndarray( N, a, sa, oa, b, sb, ob, out, so, oo\[, options] )



Fills a strided array with pseudorandom numbers drawn from an [arcsine][@stdlib/random/base/arcsine] distribution using alternative indexing semantics.



```javascript

var Float64Array = require( '@stdlib/array-float64' );



// Create an array:

var out = new Float64Array( 10 );



// Fill the array with pseudorandom numbers:

arcsine.ndarray( out.length, [ 2.0 ], 0, 0, [ 5.0 ], 0, 0, out, 1, 0 );

```



The function has the following additional parameters:



-   **oa**: starting index for `a`.

-   **ob**: starting index for `b`.

-   **oo**: starting index for `out`.



While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying `buffer`, the offset parameters support indexing semantics based on starting indices. For example, to access every other value in `out` starting from the second value,



```javascript

var out = [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ];



arcsine.ndarray( 3, [ 2.0 ], 0, 0, [ 5.0 ], 0, 0, out, 2, 1 );

```



The function accepts the same `options` as documented above for `arcsine()`.



## Notes



-   If `N <= 0`, both functions leave the output array unchanged.

-   Both functions support array-like objects having getter and setter accessors for array element access.



## Examples



```javascript

var zeros = require( '@stdlib/array-zeros' );

var zeroTo = require( '@stdlib/array-base-zero-to' );

var logEach = require( '@stdlib/console-log-each' );

var arcsine = require( '@stdlib/random-strided-arcsine' );



// Specify a PRNG seed:

var opts = {

    'seed': 1234

};



// Create an array:

var x1 = zeros( 10, 'float64' );



// Create a list of indices:

var idx = zeroTo( x1.length );



// Fill the array with pseudorandom numbers:

arcsine( x1.length, [ 2.0 ], 0, [ 5.0 ], 0, x1, 1, opts );



// Create a second array:

var x2 = zeros( 10, 'generic' );



// Fill the array with the same pseudorandom numbers:

arcsine( x2.length, [ 2.0 ], 0, [ 5.0 ], 0, x2, 1, opts );



// Print the array contents:

logEach( 'x1[%d] = %.2f; x2[%d] = %.2f', idx, x1, idx, x2 );

```



* * *



## See Also



-   [`@stdlib/random-base/arcsine`][@stdlib/random/base/arcsine]: arcsine distributed pseudorandom numbers.

-   [`@stdlib/random-array/arcsine`][@stdlib/random/array/arcsine]: create an array containing pseudorandom numbers drawn from an arcsine distribution.



* * *



## Notice



This package is part of [stdlib][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][stdlib], see the main project [repository][stdlib].



#### Community



[![Chat][chat-image]][chat-url]



---



## License



See [LICENSE][stdlib-license].



## Copyright



Copyright © 2016-2024. The Stdlib [Authors][stdlib-authors].



[npm-image]: http://img.shields.io/npm/v/@stdlib/random-strided-arcsine.svg

[npm-url]: https://npmjs.org/package/@stdlib/random-strided-arcsine



[test-image]: https://github.com/stdlib-js/random-strided-arcsine/actions/workflows/test.yml/badge.svg?branch=main

[test-url]: https://github.com/stdlib-js/random-strided-arcsine/actions/workflows/test.yml?query=branch:main



[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/random-strided-arcsine/main.svg

[coverage-url]: https://codecov.io/github/stdlib-js/random-strided-arcsine?branch=main



[chat-image]: https://img.shields.io/gitter/room/stdlib-js/stdlib.svg

[chat-url]: https://app.gitter.im/#/room/#stdlib-js_stdlib:gitter.im



[stdlib]: https://github.com/stdlib-js/stdlib



[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors



[umd]: https://github.com/umdjs/umd

[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules



[deno-url]: https://github.com/stdlib-js/random-strided-arcsine/tree/deno

[deno-readme]: https://github.com/stdlib-js/random-strided-arcsine/blob/deno/README.md

[umd-url]: https://github.com/stdlib-js/random-strided-arcsine/tree/umd

[umd-readme]: https://github.com/stdlib-js/random-strided-arcsine/blob/umd/README.md

[esm-url]: https://github.com/stdlib-js/random-strided-arcsine/tree/esm

[esm-readme]: https://github.com/stdlib-js/random-strided-arcsine/blob/esm/README.md

[branches-url]: https://github.com/stdlib-js/random-strided-arcsine/blob/main/branches.md



[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/random-strided-arcsine/main/LICENSE



[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray



[@stdlib/random/base/arcsine]: https://github.com/stdlib-js/random-base-arcsine



[@stdlib/array/uint32]: https://github.com/stdlib-js/array-uint32



[@stdlib/random/array/arcsine]: https://github.com/stdlib-js/random-array-arcsine