time-to-botec/squiggle/node_modules/@stdlib/utils/pick-by/README.md

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@license Apache-2.0
Copyright (c) 2018 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.
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# pickBy
> Return a partial object copy containing properties for which a predicate (function) returns a truthy value.
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<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. -->
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## Notes
- The function returns a **shallow** copy.
- The function **only** copies **own** properties. Hence, the function never copies inherited properties.
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## 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>
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