toInsertedAt

Return a new array containing every element from an input array and with a provided value inserted at a specified index.

Installation

npm install @stdlib/array-base-to-inserted-at

Usage

var toInsertedAt = require( '@stdlib/array-base-to-inserted-at' );

toInsertedAt( x, index, value )

Returns a new array containing every element from an input array and with a provided value inserted at a specified index.

var x = [ 1, 2, 3, 4 ];

var out = toInsertedAt( x, 0, 5 );
// returns [ 5, 1, 2, 3, 4 ]

out = toInsertedAt( x, -1, 6 );
// returns [ 1, 2, 3, 4, 6 ]

The function accepts the following arguments:

• x: an input array.
• index: element index.
• value: value to insert.

toInsertedAt.assign( x, index, value, out, stride, offset )

Copies elements from one array to another array and inserts a provided value at a specified index.

var x = [ 1, 2, 3, 4 ];

var out = [ 0, 0, 0, 0, 0 ];
var arr = toInsertedAt.assign( x, 0, 5, out, 1, 0 );
// returns [ 5, 1, 2, 3, 4 ]

var bool = ( arr === out );
// returns true

The function accepts the following arguments:

• x: an input array.
• index: element index.
• value: value to insert.
• out: output array.
• stride: output array stride.
• offset: output array offset.

Notes

• Negative indices are resolved relative to the last array element, with the last element corresponding to -1.

Examples

var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var toInsertedAt = require( '@stdlib/array-base-to-inserted-at' );

// Define an array:
var opts = {
    'dtype': 'generic'
};
var x = discreteUniform( 5, -100, 100, opts );

// Define an array containing random index values:
var indices = discreteUniform( 100, -x.length, x.length, opts );

// Define an array with random values to insert:
var values = discreteUniform( indices.length, -10000, 10000, opts );

// Randomly insert elements in the input array:
var i;
for ( i = 0; i < indices.length; i++ ) {
    console.log( 'x = [%s]', toInsertedAt( x, indices[ i ], values[ i ] ).join( ',' ) );
}

Notice

This package is part of 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, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2026. The Stdlib Authors.