Vector

Create a vector (i.e., a one-dimensional ndarray).

Installation

npm install @stdlib/ndarray-vector-ctor

Usage

var vector = require( '@stdlib/ndarray-vector-ctor' );

vector( [dtype][, options] )

Returns a one-dimensional ndarray having a specified data type.

var getDType = require( '@stdlib/ndarray-dtype' );
var numel = require( '@stdlib/ndarray-numel' );

var arr = vector();
// returns <ndarray>

var len = numel( arr );
// returns 0

var dt = getDType( arr );
// returns 'float64'

By default, the function returns an ndarray having a float64 data type. To specify an alternative data type, provide a dtype argument.

var getDType = require( '@stdlib/ndarray-dtype' );
var numel = require( '@stdlib/ndarray-numel' );

var arr = vector( 'int32' );
// returns <ndarray>

var len = numel( arr );
// returns 0

var dt = getDType( arr );
// returns 'int32'

The function accepts the following options:

• order: specifies whether an ndarray is 'row-major' (C-style) or 'column-major' (Fortran-style). Default: 'row-major'.
• mode: specifies how to handle indices which exceed array dimensions (see ndarray). Default: 'throw'.
• readonly: boolean indicating whether an array should be read-only. Default: false.

vector( length[, dtype][, options] )

Returns a one-dimensional ndarray having a specified length.

var numel = require( '@stdlib/ndarray-numel' );

var arr1 = vector( 5 );
// returns <ndarray>

var len1 = numel( arr1 );
// returns 5

var arr2 = vector( 5, 'uint8' );
// returns <ndarray>

var len2 = numel( arr2 );
// returns 5

vector( obj[, dtype][, options] )

Creates a one-dimensional ndarray from an array-like object or iterable.

var numel = require( '@stdlib/ndarray-numel' );

var arr1 = vector( [ 0.5, 0.5, 0.5 ] );
// returns <ndarray>

var len1 = numel( arr1 );
// returns 3

var arr2 = vector( [ 0.5, 0.5, 0.5 ], 'float32' );
// returns <ndarray>

var len2 = numel( arr2 );
// returns 3

vector( buffer[, byteOffset[, length]][, dtype][, options] )

Returns a one-dimensional ndarray view of an ArrayBuffer.

var ArrayBuffer = require( '@stdlib/array-buffer' );
var getDType = require( '@stdlib/ndarray-dtype' );
var numel = require( '@stdlib/ndarray-numel' );

var buf = new ArrayBuffer( 32 );

var arr1 = vector( buf );
// returns <ndarray>

var len1 = numel( arr1 );
// returns 4

var dt1 = getDType( arr1 );
// returns 'float64'

var arr2 = vector( buf, 'float32' );
// returns <ndarray>

var len2 = numel( arr2 );
// returns 8

var dt2 = getDType( arr2 );
// returns 'float32'

var arr3 = vector( buf, 16 );
// returns <ndarray>

var len3 = numel( arr3 );
// returns 2

var dt3 = getDType( arr3 );
// returns 'float64'

var arr4 = vector( buf, 16, 'float32' );
// returns <ndarray>

var len4 = numel( arr4 );
// returns 4

var dt4 = getDType( arr4 );
// returns 'float32'

var arr5 = vector( buf, 16, 1 );
// returns <ndarray>

var len5 = numel( arr5 );
// returns 1

var dt5 = getDType( arr5 );
// returns 'float64'

var arr6 = vector( buf, 10, 4, 'int16' );
// returns <ndarray>

var len6 = numel( arr6 );
// returns 4

var dt6 = getDType( arr6 );
// returns 'int16'

vector.factory( dtype[, options] )

Returns a function for creating a one-dimensional ndarray.

var getDType = require( '@stdlib/ndarray-dtype' );
var numel = require( '@stdlib/ndarray-numel' );

var Float32Vector = vector.factory( 'float32' );

var arr = new Float32Vector( [ 1, 2, 3 ] );
// returns <ndarray>

var dt = getDType( arr );
// returns 'float32'

var len = numel( arr );
// returns 3

The function supports the following parameters:

• dtype: data type.
• options: function options (optional).

The function accepts the following options:

• order: specifies whether the default memory layout for a returned ndarray should be 'row-major' (C-style) or 'column-major' (Fortran-style). Default: 'row-major'.
• mode: specifies the default behavior when handling indices which exceed array dimensions (see ndarray). Default: 'throw'.
• readonly: boolean indicating whether to return a read-only ndarray by default. Default: false.

The function returned by the factory method supports the same arguments and options as vector above, except for the dtype argument, as the returned function always returns a one-dimensional ndarray having the same data type.

When providing options to the returned function, the provided option values override the defaults established during function creation.

Examples

var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var cartesianProduct = require( '@stdlib/array-cartesian-product' );
var unzip = require( '@stdlib/utils-unzip' );
var dtypes = require( '@stdlib/ndarray-dtypes' );
var sum = require( '@stdlib/blas-ext-sum' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var vector = require( '@stdlib/ndarray-vector-ctor' );

// Create an array of random array lengths:
var lens = discreteUniform( 10, 5, 15, {
    'dtype': 'int32'
});

// Resolve a list of supported ndarray real-valued data types:
var dts = dtypes( 'real_and_generic' );

// Create length-dtype pairs:
var pairs = cartesianProduct( lens, dts );

// Split the pairs into individual arguments:
var args = unzip( pairs );

// Define a callback to create a random vector and return the sum of all vector elements:
function clbk( len, dtype ) {
    var x = vector( discreteUniform( len, 0, 100 ), dtype );
    return sum( x ).get();
}

// Apply the callback and print the results:
logEachMap( 'len: %2d. dtype: %7s. sum: %d.', args[ 0 ], args[ 1 ], clbk );

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.