@stdlib/stats-incr-mean
v0.2.3TypeScript
Compute an arithmetic mean incrementally.
598/weekUpdated 1 weeks agoApache-2.0Unpacked: 35.8 KB
Published by The Stdlib Authors
npm install @stdlib/stats-incr-meanWe 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!
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incrmean
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> Compute an [arithmetic mean][arithmetic-mean] incrementally.
The [arithmetic mean][arithmetic-mean] is defined as
Installation
``bash`
npm install @stdlib/stats-incr-mean
Usage
`javascript`
var incrmean = require( '@stdlib/stats-incr-mean' );
#### incrmean()
Returns an accumulator function which incrementally computes an [arithmetic mean][arithmetic-mean].
`javascript`
var accumulator = incrmean();
#### accumulator( \[x] )
If provided an input value x, the accumulator function returns an updated mean. If not provided an input value x, the accumulator function returns the current mean.
`javascript
var accumulator = incrmean();
var mu = accumulator( 2.0 );
// returns 2.0
mu = accumulator( 1.0 );
// returns 1.5
mu = accumulator( 3.0 );
// returns 2.0
mu = accumulator();
// returns 2.0
`
Notes
- Input values are not type checked. If provided NaN or a value which, when used in computations, results in NaN, the accumulated value is NaN for all future invocations. If non-numeric inputs are possible, you are advised to type check and handle accordingly before passing the value to the accumulator function.
Examples
`javascript
var randu = require( '@stdlib/random-base-randu' );
var incrmean = require( '@stdlib/stats-incr-mean' );
var accumulator;
var v;
var i;
// Initialize an accumulator:
accumulator = incrmean();
// For each simulated datum, update the mean...
for ( i = 0; i < 100; i++ ) {
v = randu() * 100.0;
accumulator( v );
}
console.log( accumulator() );
`
*
See Also
- [@stdlib/stats-incr/midrange][@stdlib/stats/incr/midrange]: compute a mid-range incrementally.
- [@stdlib/stats-incr/mmean][@stdlib/stats/incr/mmean]: compute a moving arithmetic mean incrementally.
- [@stdlib/stats-incr/stdev][@stdlib/stats/incr/stdev]: compute a corrected sample standard deviation incrementally.
- [@stdlib/stats-incr/sum][@stdlib/stats/incr/sum]: compute a sum incrementally.
- [@stdlib/stats-incr/summary][@stdlib/stats/incr/summary]: compute a statistical summary incrementally.
- [@stdlib/stats-incr/variance][@stdlib/stats/incr/variance]: compute an unbiased sample variance incrementally.
*
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 © 2016-2026. The Stdlib [Authors][stdlib-authors].
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[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/stats-incr-mean/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/stats-incr-mean?branch=main
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[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/stats-incr-mean/tree/deno
[deno-readme]: https://github.com/stdlib-js/stats-incr-mean/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/stats-incr-mean/tree/umd
[umd-readme]: https://github.com/stdlib-js/stats-incr-mean/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/stats-incr-mean/tree/esm
[esm-readme]: https://github.com/stdlib-js/stats-incr-mean/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/stats-incr-mean/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/stats-incr-mean/main/LICENSE
[arithmetic-mean]: https://en.wikipedia.org/wiki/Arithmetic_mean
[@stdlib/stats/incr/midrange]: https://www.npmjs.com/package/@stdlib/stats-incr-midrange
[@stdlib/stats/incr/mmean]: https://www.npmjs.com/package/@stdlib/stats-incr-mmean
[@stdlib/stats/incr/stdev]: https://www.npmjs.com/package/@stdlib/stats-incr-stdev
[@stdlib/stats/incr/sum]: https://www.npmjs.com/package/@stdlib/stats-incr-sum
[@stdlib/stats/incr/summary]: https://www.npmjs.com/package/@stdlib/stats-incr-summary
[@stdlib/stats/incr/variance]: https://www.npmjs.com/package/@stdlib/stats-incr-variance