npm package: @stdlib/random-array-tools-unary-factory
Description: Create a factory function for generating pseudorandom values drawn from a unary PRNG.
Author: The Stdlib Authors
Latest version: 0.2.3

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# unaryFactory

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> Create a factory function for generating pseudorandom values drawn from a unary PRNG.

<section class="installation">

## Installation

```bash
npm install @stdlib/random-array-tools-unary-factory
```

</section>

<section class="usage">

## Usage

```javascript
var unaryFactory = require( '@stdlib/random-array-tools-unary-factory' );
```

#### unaryFactory( prng, dtypes, dtype )

Returns a factory function for generating pseudorandom values drawn from a unary PRNG.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, 'float64' );
// returns <Function>
```

The function has the following parameters:

-   **prng**: unary pseudorandom number generator.
-   **dtypes**: list of supported output data types.
-   **dtype**: default output array data type.

* * *

#### factory( \[param1, ]\[options] )

Returns a function for generating pseudorandom values drawn from a unary PRNG.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>
```

The function has the following parameters:

-   **param1**: PRNG parameter. If provided a PRNG parameter, the function returns a partially applied function for creating arrays, which can be useful when wanting to pass around a parameterized function for array creation.
-   **options**: function options.

The function supports the following options:

-   **prng**: pseudorandom number generator which generates uniformly distributed pseudorandom numbers.
-   **seed**: pseudorandom value generator seed.
-   **state**: pseudorandom value generator state.
-   **copy**: boolean indicating whether to copy a provided pseudorandom value generator state.
-   **dtype**: default output array data type. Setting this option overrides the default output array data type provided to the parent function.

* * *

### Full Arity

#### random( len, param1\[, options] )

Returns an array of pseudorandom values drawn from a unary PRNG.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var v = random( 10, 2.0 );
// returns <Float64Array>
```

The function has the following parameters:

-   **len**: output array length.
-   **param1**: PRNG parameter.
-   **options**: function options.

The function accepts the following options:

-   **dtype**: output array data type. Setting this option overrides the default output array data type.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var v = random( 10, 2.0, {
    'dtype': 'float32'
});
// returns <Float32Array>
```

#### random.assign( param1, out )

Fills an array with pseudorandom values drawn from a unary PRNG.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );
var zeros = require( '@stdlib/array-zeros' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var out = zeros( 10, 'float64' );
// returns <Float64Array>

var v = random.assign( 2.0, out );
// returns <Float64Array>

var bool = ( out === v );
// returns true
```

The method has the following parameters:

-   **param1**: PRNG parameter.
-   **out**: output array.

### Partial Application

#### random( len\[, options] )

Returns an array of pseudorandom values drawn from a unary PRNG.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory( 2.0 );
// returns <Function>

var v = random( 10 );
// returns <Float64Array>

v = random( 10 );
// returns <Float64Array>
```

The function has the following parameters:

-   **len**: output array length.
-   **options**: function options.

The function accepts the following options:

-   **dtype**: output array data type. Setting this option overrides the default output array data type.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory( 2.0 );
// returns <Function>

var v = random( 10, {
    'dtype': 'float32'
});
// returns <Float32Array>

v = random( 10, {
    'dtype': 'generic'
});
// returns [...]
```

#### random.assign( out )

Fills an array with pseudorandom values drawn from a unary PRNG.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );
var zeros = require( '@stdlib/array-zeros' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory( 2.0 );
// returns <Function>

var out = zeros( 10, 'float64' );
// returns <Float64Array>

var v = random.assign( out );
// returns <Float64Array>

var bool = ( out === v );
// returns true
```

The method has the following parameters:

-   **out**: output array.

* * *

#### random.PRNG

The underlying pseudorandom number generator.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var prng = random.PRNG;
// returns <Function>
```

#### random.seed

The value used to seed the underlying pseudorandom number generator.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var seed = random.seed;
// returns <Uint32Array>
```

If the `factory` function is provided a PRNG for uniformly distributed numbers, the associated property value on the returned function is `null`.

```javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory({
    'prng': minstd
});
// returns <Function>

var seed = random.seed;
// returns null
```

#### random.seedLength

Length of underlying pseudorandom number generator seed.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var len = random.seedLength;
// returns <number>
```

If the `factory` function is provided a PRNG for uniformly distributed numbers, the associated property value on the returned function is `null`.

```javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory({
    'prng': minstd
});
// returns <Function>

var len = random.seedLength;
// returns null
```

#### random.state

Writable property for getting and setting the underlying pseudorandom number generator state.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var state = random.state;
// returns <Uint32Array>
```

If the `factory` function is provided a PRNG for uniformly distributed numbers, the associated property value on the returned function is `null`.

```javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory({
    'prng': minstd
});
// returns <Function>

var state = random.state;
// returns null
```

#### random.stateLength

Length of underlying pseudorandom number generator state.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var len = random.stateLength;
// returns <number>
```

If the `factory` function is provided a PRNG for uniformly distributed numbers, the associated property value on the returned function is `null`.

```javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory({
    'prng': minstd
});
// returns <Function>

var len = random.stateLength;
// returns null
```

#### random.byteLength

Size (in bytes) of underlying pseudorandom number generator state.

```javascript
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory();
// returns <Function>

var sz = random.byteLength;
// returns <number>
```

If the `factory` function is provided a PRNG for uniformly distributed numbers, the associated property value on the returned function is `null`.

```javascript
var minstd = require( '@stdlib/random-base-minstd-shuffle' ).normalized;
var exponential = require( '@stdlib/random-base-exponential' );

var dtypes = [ 'float64', 'float32', 'generic' ];

var factory = unaryFactory( exponential, dtypes, dtypes[ 0 ] );
// returns <Function>

var random = factory({
    'prng': minstd
});
// returns <Function>

var sz = random.byteLength;
// returns null
```

</section>

<!-- /.usage -->

<section class="notes">

</section>

<!-- /.notes -->

<section class="examples">

* * *

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var exponential = require( '@stdlib/random-base-exponential' );
var dtypes = require( '@stdlib/array-dtypes' );
var unaryFactory = require( '@stdlib/random-array-tools-unary-factory' );

var dt = dtypes( 'real_floating_point_and_generic' );

var factory = unaryFactory( exponential, dt, 'float64' );
// returns <Function>

var random = factory();
// returns <Function>

var x = random( 10, 2.0 );
// returns <Float64Array>

x = random( 10, 2.0, {
    'dtype': 'float32'
});
// returns <Float32Array>

x = random( 10, 2.0, {
    'dtype': 'generic'
});
// returns [...]
```

</section>

<!-- /.examples -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

</section>

<!-- /.related -->

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<section class="main-repo" >

* * *

## 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

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

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