Return the data type of an array.
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> Return the data type of an array.
``bash`
npm install @stdlib/array-dtype
`javascript`
var dtype = require( '@stdlib/array-dtype' );
#### dtype( array )
Returns the [data type][@stdlib/array/dtypes] of an array.
`javascript
var Float64Array = require( '@stdlib/array-float64' );
var arr = new Float64Array( 10 );
var dt = dtype( arr );
// returns 'float64'
`
If provided an argument having an unknown or unsupported [data type][@stdlib/array/dtypes], the function returns null.
`javascript`
var dt = dtype( 'beep' );
// returns null
`javascript
var dtypes = require( '@stdlib/array-dtypes' );
var ctors = require( '@stdlib/array-ctors' );
var dtype = require( '@stdlib/array-dtype' );
var DTYPES;
var ctor;
var arr;
var len;
var dt;
var i;
// Get a list of supported array data types:
DTYPES = dtypes();
// Array length:
len = 10;
// For each supported data type, create an array and confirm its data type...
for ( i = 0; i < DTYPES.length; i++ ) {
ctor = ctors( DTYPES[ i ] );
arr = new ctor( len );
dt = dtype( arr );
console.log( '%s == %s => %s', DTYPES[ i ], dt, DTYPES[ i ] === dt );
}
`
*
- [@stdlib/array-dtypes][@stdlib/array/dtypes]: list of array data types.
*
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].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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