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110 changes: 110 additions & 0 deletions lib/node_modules/@stdlib/stats/array/mean/README.md
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@@ -0,0 +1,110 @@
<!--

@license Apache-2.0

Copyright (c) 2025 The Stdlib Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

-->

# mean

> Calculate the [arithmetic mean][arithmetic-mean] of an array.

<section class="intro">

</section>

<!-- /.intro -->

<section class="usage">

## Usage

```javascript
var mean = require( '@stdlib/stats/array/mean' );
```

#### mean( x )

Computes the [arithmetic mean][arithmetic-mean] of an array.

```javascript
var x = [ 1.0, -2.0, 2.0 ];

var v = mean( x );
// returns ~0.3333
```

The function has the following parameters:

- **x**: input array.

</section>

<!-- /.usage -->

<section class="notes">

## Notes

- If provided an empty array, the function returns `NaN`.
- The function supports array-like objects having getter and setter accessors for array element access (e.g., [`@stdlib/array/base/accessor`][@stdlib/array/base/accessor]).

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var mean = require( '@stdlib/stats/array/mean' );

var x = discreteUniform( 10, -50, 50, {
'dtype': 'float64'
});
console.log( x );

var v = mean( x );
console.log( v );
```

</section>

<!-- /.examples -->

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

<section class="related">

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

[arithmetic-mean]: https://en.wikipedia.org/wiki/Arithmetic_mean

[@stdlib/array/base/accessor]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/array/base/accessor

</section>

<!-- /.links -->
96 changes: 96 additions & 0 deletions lib/node_modules/@stdlib/stats/array/mean/benchmark/benchmark.js
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/**
* @license Apache-2.0
*
* Copyright (c) 2025 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

// MODULES //

var bench = require( '@stdlib/bench' );
var uniform = require( '@stdlib/random/array/uniform' );
var isnan = require( '@stdlib/math/base/assert/is-nan' );
var pow = require( '@stdlib/math/base/special/pow' );
var pkg = require( './../package.json' ).name;
var mean = require( './../lib' );


// VARIABLES //

var options = {
'dtype': 'generic'
};


// FUNCTIONS //

/**
* Creates a benchmark function.
*
* @private
* @param {PositiveInteger} len - array length
* @returns {Function} benchmark function
*/
function createBenchmark( len ) {
var x = uniform( len, -10, 10, options );
return benchmark;

function benchmark( b ) {
var v;
var i;

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
v = mean( x );
if ( isnan( v ) ) {
b.fail( 'should not return NaN' );
}
}
b.toc();
if ( isnan( v ) ) {
b.fail( 'should not return NaN' );
}
b.pass( 'benchmark finished' );
b.end();
}
}


// MAIN //

/**
* Main execution sequence.
*
* @private
*/
function main() {
var len;
var min;
var max;
var f;
var i;

min = 1; // 10^min
max = 6; // 10^max

for ( i = min; i <= max; i++ ) {
len = pow( 10, i );
f = createBenchmark( len );
bench( pkg+':len='+len, f );
}
}

main();
25 changes: 25 additions & 0 deletions lib/node_modules/@stdlib/stats/array/mean/docs/repl.txt
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{{alias}}( x )
Computes the arithmetic mean of an array.

If provided an empty array, the function returns `NaN`.

Parameters
----------
x: Array<number>|TypedArray
Input array.

Returns
-------
out: number
The arithmetic mean.

Examples
--------
> var x = [ 1.0, -2.0, 2.0 ];
> {{alias}}( x )
~0.3333

See Also
--------

47 changes: 47 additions & 0 deletions lib/node_modules/@stdlib/stats/array/mean/docs/types/index.d.ts
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/*
* @license Apache-2.0
*
* Copyright (c) 2025 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

// TypeScript Version: 4.1

/// <reference types="@stdlib/types"/>

import { NumericArray, Collection, AccessorArrayLike } from '@stdlib/types/array';

/**
* Input array.
*/
type InputArray = NumericArray | Collection<number> | AccessorArrayLike<number>;
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This is fine for now. Once we add strided implementations for computing the sum/mean of arrays containing complex numbers, we'll want to revisit.


/**
* Computes the arithmetic mean of an array.
*
* @param x - input array
* @returns arithmetic mean
*
* @example
* var x = [ 1.0, -2.0, 2.0 ];
*
* var v = mean( x );
* // returns ~0.3333
*/
declare function mean( x: InputArray ): number;


// EXPORTS //

export = mean;
51 changes: 51 additions & 0 deletions lib/node_modules/@stdlib/stats/array/mean/docs/types/test.ts
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/*
* @license Apache-2.0
*
* Copyright (c) 2025 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

import AccessorArray = require( '@stdlib/array/base/accessor' );
import mean = require( './index' );


// TESTS //

// The function returns a number...
{
const x = new Float64Array( 10 );

mean( x ); // $ExpectType number
mean( new AccessorArray( x ) ); // $ExpectType number
}

// The compiler throws an error if the function is provided a first argument which is not a numeric array...
{
mean( 10 ); // $ExpectError
mean( '10' ); // $ExpectError
mean( true ); // $ExpectError
mean( false ); // $ExpectError
mean( null ); // $ExpectError
mean( undefined ); // $ExpectError
mean( {} ); // $ExpectError
mean( ( x: number ): number => x ); // $ExpectError
}

// The compiler throws an error if the function is provided an unsupported number of arguments...
{
const x = new Float64Array( 10 );

mean(); // $ExpectError
mean( x, {} ); // $ExpectError
}
30 changes: 30 additions & 0 deletions lib/node_modules/@stdlib/stats/array/mean/examples/index.js
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/**
* @license Apache-2.0
*
* Copyright (c) 2025 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var mean = require( './../lib' );

var x = discreteUniform( 10, -50, 50, {
'dtype': 'float64'
});
console.log( x );

var v = mean( x );
console.log( v );
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