Resolve the data type that results from applying promotion rules to a provided list of data types.
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> Resolve the data type that results from applying [promotion rules][@stdlib/ndarray/promotion-rules] to a provided list of data types.
``bash`
npm install @stdlib/ndarray-base-promote-dtypes
`javascript`
var promoteDataTypes = require( '@stdlib/ndarray-base-promote-dtypes' );
#### promoteDataTypes( dtypes )
Returns a data type that results from applying [promotion rules][@stdlib/ndarray/promotion-rules] to a provided list of data types.
`javascript`
var dt = promoteDataTypes( [ 'float32', 'float64' ] );
// returns 'float64'
The function returns null if provided data types which cannot be safely cast to a promoted data type.
`javascript`
var dt = promoteDataTypes( [ 'binary', 'complex128' ] );
// returns null
`javascript
var dtypes = require( '@stdlib/ndarray-dtypes' );
var cartesianProduct = require( '@stdlib/array-base-cartesian-product' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var promoteDataTypes = require( '@stdlib/ndarray-base-promote-dtypes' );
// Get the list of supported data types:
var dt = dtypes();
// Generate data type pairs:
var pairs = cartesianProduct( dt, dt );
// Resolve promoted data types:
logEachMap( '(%s) => %s', pairs, promoteDataTypes );
`
*
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.
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---
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