Flatten an n-dimensional nested array.
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> Flatten an n-dimensional nested array.
``bash`
npm install @stdlib/array-base-flatten
`javascript`
var flatten = require( '@stdlib/array-base-flatten' );
#### flatten( x, shape, colexicographic )
Flattens an n-dimensional nested array.
`javascript
var x = [ [ 1, 2 ], [ 3, 4 ] ];
var out = flatten( x, [ 2, 2 ], false );
// returns [ 1, 2, 3, 4 ]
`
To flatten in colexicographic order, provide a third argument equal to true.
`javascript
var x = [ [ 1, 2 ], [ 3, 4 ] ];
var out = flatten( x, [ 2, 2 ], true );
// returns [ 1, 3, 2, 4 ]
`
#### flatten.assign( x, shape, colexicographic, out, stride, offset )
Flattens an n-dimensional nested array and assigns elements to a provided output array.
`javascript
var Float64Array = require( '@stdlib/array-float64' );
var x = [ [ 1, 2 ], [ 3, 4 ] ];
var out = new Float64Array( 4 );
var y = flatten.assign( x, [ 2, 2 ], false, out, 1, 0 );
// returns
var bool = ( y === out );
// returns true
y = flatten.assign( x, [ 2, 2 ], true, out, 1, 0 );
// returns
`
- Both functions assume that all nested arrays have the same length (i.e., the input array is not a ragged array).
`javascript
var flatten = require( '@stdlib/array-base-flatten' );
// Define a 2x2x1x2x2 array:
var x = [
[
[
[
[ 1, 2 ], [ 3, 4 ]
]
],
[
[
[ 5, 6 ], [ 7, 8 ]
]
]
],
[
[
[
[ 9, 10 ], [ 11, 12 ]
]
],
[
[
[ 13, 14 ], [ 15, 16 ]
]
]
]
];
var out = flatten( x, [ 0, 0, 0, 0, 0 ], false );
// returns []
out = flatten( x, [ 0, 0, 0, 0, 0 ], true );
// returns []
out = flatten( x, [ 1, 1, 1, 1, 1 ], false );
// returns [ 1 ]
out = flatten( x, [ 1, 1, 1, 1, 1 ], true );
// returns [ 1 ]
out = flatten( x, [ 1, 2, 1, 2, 2 ], false );
// returns [ 1, 2, 3, 4, 5, 6, 7, 8 ]
out = flatten( x, [ 1, 2, 1, 2, 2 ], true );
// returns [ 1, 5, 3, 7, 2, 6, 4, 8 ]
out = flatten( x, [ 2, 2, 1, 2, 2 ], false );
// returns [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 ]
out = flatten( x, [ 2, 2, 1, 2, 2 ], true );
// returns [ 1, 9, 5, 13, 3, 11, 7, 15, 2, 10, 6, 14, 4, 12, 8, 16 ]
`
*
- [@stdlib/array-base/flatten-by][@stdlib/array/base/flatten-by]: flatten an n-dimensional nested array according to a callback function.
*
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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---
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