npm package: @stdlib/ndarray-base-assert-is-mostly-safe-data-type-cast
Description: Determine if an ndarray data type can be safely cast or, for floating-point data types, downcast to another ndarray data type.
Author: The Stdlib Authors
Latest version: 0.3.1

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# isMostlySafeCast

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> Determine whether an ndarray [data type][@stdlib/ndarray/dtypes] can be safely cast or, for floating-point data types, downcast to another ndarray [data type][@stdlib/ndarray/dtypes].

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<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-base-assert-is-mostly-safe-data-type-cast
```

</section>

<section class="usage">

## Usage

```javascript
var isMostlySafeCast = require( '@stdlib/ndarray-base-assert-is-mostly-safe-data-type-cast' );
```

#### isMostlySafeCast( from, to )

Returns a boolean indicating whether an ndarray [data type][@stdlib/ndarray/dtypes] can be safely cast or, for floating-point data types, downcast to another ndarray [data type][@stdlib/ndarray/dtypes].

```javascript
var bool = isMostlySafeCast( 'float32', 'float64' );
// returns true

bool = isMostlySafeCast( 'float64', 'int32' );
// returns false
```

</section>

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<section class="examples">

## Examples

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

```javascript
var cartesianSquare = require( '@stdlib/array-cartesian-square' );
var dtypes = require( '@stdlib/ndarray-base-dtype-strings' );
var isMostlySafeCast = require( '@stdlib/ndarray-base-assert-is-mostly-safe-data-type-cast' );

// Generate a list of dtype pairs:
var dt = cartesianSquare( dtypes() );

// For each data type pair, determine whether one can cast to another data type...
var i;
for ( i = 0; i < dt.length; i++ ) {
    console.log( '%s. Can cast? %s.', dt[i].join( ' => ' ), isMostlySafeCast.apply( null, dt[i] ) );
}
```

</section>

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* * *

## 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

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---

## License

See [LICENSE][stdlib-license].


## Copyright

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

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