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

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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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## 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 }
```

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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 }
```

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