npm package: @stdlib/utils-pick-by
Description: Return a partial object copy containing properties for which a predicate (function) returns a truthy value.
Author: The Stdlib Authors
Latest version: 0.2.3

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# pickBy

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

> Return a partial object copy containing properties for which a predicate (function) returns a truthy value.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/utils-pick-by
```

</section>

<section class="usage">

## Usage

```javascript
var pickBy = require( '@stdlib/utils-pick-by' );
```

#### pickBy( obj, predicate )

Returns a partial object copy containing properties for which a `predicate` returns a truthy value.

```javascript
function predicate( key, value ) {
    return ( value > 1 );
}

var obj1 = {
    'a': 1,
    'b': 2,
    'c': 3
};

var obj2 = pickBy( obj1, predicate );
// returns { 'b': 2, 'c': 3 }
```

</section>

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<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## Notes

-   The function returns a **shallow** copy.
-   The function **only** copies **own** properties. Hence, the function never copies inherited properties.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var pickBy = require( '@stdlib/utils-pick-by' );

function predicate( key, value ) {
    return ( typeof value === 'number' );
}

var obj1 = {
    'a': '1',
    'b': 2,
    'c': NaN,
    'd': null
};

var obj2 = pickBy( obj1, predicate );
// returns { 'b': 2, 'c': NaN }
```

</section>

<!-- /.examples -->

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* * *

## See Also

-   <span class="package-name">[`@stdlib/utils-pick`][@stdlib/utils/pick]</span><span class="delimiter">: </span><span class="description">return a partial object copy containing only specified keys.</span>

</section>

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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

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

---

## License

See [LICENSE][stdlib-license].


## Copyright

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

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[npm-url]: https://npmjs.org/package/@stdlib/utils-pick-by

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

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[umd]: https://github.com/umdjs/umd
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/utils-pick-by/main/LICENSE

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[@stdlib/utils/pick]: https://www.npmjs.com/package/@stdlib/utils-pick

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</section>

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