Return a one-dimensional ndarray formed by prepending provided scalar values to a one-dimensional input ndarray.
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> Return a one-dimensional [ndarray][@stdlib/ndarray/ctor] formed by prepending provided scalar values to a one-dimensional input [ndarray][@stdlib/ndarray/ctor].
``bash`
npm install @stdlib/ndarray-unshift
`javascript`
var unshift = require( '@stdlib/ndarray-unshift' );
#### unshift( x, ...values )
Returns a one-dimensional [ndarray][@stdlib/ndarray/ctor] formed by prepending provided scalar values to a one-dimensional input [ndarray][@stdlib/ndarray/ctor].
`javascript
var array = require( '@stdlib/ndarray-array' );
var x = array( [ 1.0, 2.0, 3.0, 4.0 ] );
var out = unshift( x, -2.0, -1.0, 0.0 );
// returns
`
The function accepts the following arguments:
- x: input [ndarray][@stdlib/ndarray/ctor]. Must be one-dimensional.
- ...values: scalar values to prepend.
#### unshift.assign( x, ...values, out )
Prepends provided scalar values to a one-dimensional input [ndarray][@stdlib/ndarray/ctor] and assigns the result to a provided one-dimensional output [ndarray][@stdlib/ndarray/ctor].
`javascript
var array = require( '@stdlib/ndarray-array' );
var zeros = require( '@stdlib/ndarray-zeros' );
var x = array( [ 1.0, 2.0, 3.0, 4.0 ] );
var y = zeros( [ 7 ] );
var out = unshift.assign( x, -2.0, -1.0, 0.0, y );
// returns
var bool = ( out === y );
// returns true
`
The function accepts the following arguments:
- x: input [ndarray][@stdlib/ndarray/ctor]. Must be one-dimensional.
- ...values: scalar values to prepend.
- out: output [ndarray][@stdlib/ndarray/ctor]. Must be one-dimensional.
- Scalar values are cast to the [data type][@stdlib/ndarray/dtypes] of the input [ndarray][@stdlib/ndarray/ctor].
`javascript
var discreteUniform = require( '@stdlib/random-discrete-uniform' );
var ndarray2array = require( '@stdlib/ndarray-to-array' );
var unshift = require( '@stdlib/ndarray-unshift' );
var opts = {
'dtype': 'generic'
};
var x = discreteUniform( [ 6 ], 0, 10, opts );
console.log( ndarray2array( x ) );
var out = unshift( x, 12, 14 );
console.log( ndarray2array( out ) );
`
*
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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