flatten4d

Flatten a four-dimensional nested array.

Installation

npm install @stdlib/array-base-flatten4d

Usage

var flatten4d = require( '@stdlib/array-base-flatten4d' );

flatten4d( x, shape, colexicographic )

Flattens a four-dimensional nested array.

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

var out = flatten4d( x, [ 2, 1, 1, 2 ], false );
// returns [ 1, 2, 3, 4 ]

To flatten in colexicographic order, provide a third argument equal to true.

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

var out = flatten4d( x, [ 2, 1, 1, 2 ], true );
// returns [ 1, 3, 2, 4 ]

flatten4d.assign( x, shape, colexicographic, out, stride, offset )

Flattens a four-dimensional nested array and assigns elements to a provided output array.

var Float64Array = require( '@stdlib/array-float64' );

var x = [ [ [ [ 1, 2 ] ] ], [ [ [ 3, 4 ] ] ] ];
var out = new Float64Array( 4 );

var y = flatten4d.assign( x, [ 2, 1, 1, 2 ], false, out, 1, 0 );
// returns <Float64Array>[ 1, 2, 3, 4 ]

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

y = flatten4d.assign( x, [ 2, 1, 1, 2 ], true, out, 1, 0 );
// returns <Float64Array>[ 1, 3, 2, 4 ]

Notes

• Both functions assume that all nested arrays have the same length (i.e., the input array is not a ragged array).

Examples

var flatten4d = require( '@stdlib/array-base-flatten4d' );

// Define a 2x2x2x2 array:
var x = [
    [
        [ [ 1, 2 ], [ 3, 4 ] ],
        [ [ 5, 6 ], [ 7, 8 ] ]
    ],
    [
        [ [ 9, 10 ], [ 11, 12 ] ],
        [ [ 13, 14 ], [ 15, 16 ] ]
    ]
];

var out = flatten4d( x, [ 0, 0, 0, 0 ], false );
// returns []

out = flatten4d( x, [ 0, 0, 0, 0 ], true );
// returns []

out = flatten4d( x, [ 1, 1, 1, 1 ], false );
// returns [ 1 ]

out = flatten4d( x, [ 1, 1, 1, 1 ], true );
// returns [ 1 ]

out = flatten4d( x, [ 1, 2, 2, 2 ], false );
// returns [ 1, 2, 3, 4, 5, 6, 7, 8 ]

out = flatten4d( x, [ 1, 2, 2, 2 ], true );
// returns [ 1, 5, 3, 7, 2, 6, 4, 8 ]

out = flatten4d( x, [ 2, 2, 2, 2 ], false );
// returns [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 ]

out = flatten4d( x, [ 2, 2, 2, 2 ], true );
// returns [ 1, 9, 5, 13, 3, 11, 7, 15, 2, 10, 6, 14, 4, 12, 8, 16 ]

See Also

• @stdlib/array-base/flatten4d-by: flatten a four-dimensional nested array according to a callback function.

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 © 2016-2024. The Stdlib Authors.