time-to-botec/squiggle/node_modules/@stdlib/ndarray/base/to-array/README.md

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@license Apache-2.0
Copyright (c) 2018 The Stdlib Authors.
Licensed under the Apache License, Version 2.0 (the "License");
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# ndarray2array
> Convert an ndarray buffer to a generic array.
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## Usage
```javascript
var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
```
#### ndarray2array( buffer, shape, strides, offset, order )
Converts an ndarray buffer to a generic array (which may include nested arrays).
```javascript
var buffer = [ 1, 2, 3, 4 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;
var arr = ndarray2array( buffer, shape, strides, offset, order );
// returns [ [ 1, 2 ], [ 3, 4 ] ]
```
The `order` parameter specifies whether an array is `row-major` (C-style) or `column-major` (Fortran-style).
```javascript
var buffer = [ 1, 2, 3, 4 ];
var shape = [ 2, 2 ];
var order = 'column-major';
var strides = [ 1, 2 ];
var offset = 0;
var arr = ndarray2array( buffer, shape, strides, offset, order );
// returns [ [ 1, 3 ], [ 2, 4 ] ]
```
The `offset` parameter specifies the location of the first indexed element based on the `strides` array.
```javascript
var buffer = [ 1, 2, 3, 4 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ -2, -1 ];
var offset = 3;
var arr = ndarray2array( buffer, shape, strides, offset, order );
// returns [ [ 4, 3 ], [ 2, 1 ] ]
```
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## Examples
<!-- eslint no-undef: "error" -->
```javascript
var shape2strides = require( '@stdlib/ndarray/base/shape2strides' );
var strides2offset = require( '@stdlib/ndarray/base/strides2offset' );
var dicreteUniform = require( '@stdlib/random/base/discrete-uniform' );
var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
// Create a data buffer:
var buffer = [];
var i;
for ( i = 0; i < 27; i++ ) {
buffer.push( i );
}
// Specify array meta data:
var shape = [ 3, 3, 3 ];
var order = 'column-major';
var ndims = shape.length;
// Compute array meta data:
var strides = shape2strides( shape, order );
var offset = strides2offset( shape, strides );
// Print array information:
console.log( '' );
console.log( 'Dims: %s', shape.join( 'x' ) );
// Random flip strides and convert an ndarray to a nested array...
var arr;
var j;
for ( i = 0; i < 20; i++ ) {
j = dicreteUniform( 0, ndims-1 );
strides[ j ] *= -1;
offset = strides2offset( shape, strides );
console.log( '' );
console.log( 'Strides: %s', strides.join( ',' ) );
console.log( 'Offset: %d', offset );
arr = ndarray2array( buffer, shape, strides, offset, order );
console.log( JSON.stringify( arr ) );
}
```
</section>
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