npm package: @stdlib/ndarray-ctor
Description: Multidimensional array constructor.
Author: The Stdlib Authors
Latest version: 0.3.1

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# ndarray

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Multidimensional array constructor.

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

<!-- /.intro -->

<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-ctor
```

</section>

<section class="usage">

## Usage

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

<a name="main"></a>

#### ndarray( dtype, buffer, shape, strides, offset, order\[, options] )

Returns an `ndarray` instance.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );
// returns <ndarray>
```

The constructor expects the following arguments:

-   **dtype**: underlying [data type][@stdlib/ndarray/dtypes].
-   **buffer**: data buffer.
-   **shape**: array shape (dimensions).
-   **strides**: array strides which are index offsets specifying how to access along corresponding dimensions.
-   **offset**: index offset specifying the location of the first indexed element in the data buffer.
-   **order**: array order, which is either `row-major` (C-style) or `column-major` (Fortran-style).

The constructor accepts the following `options`:

-   **mode**: specifies how to handle indices which exceed array dimensions. Default: `'throw'`.
-   **submode**: a mode array which specifies for each dimension how to handle subscripts which exceed array dimensions. If provided fewer modes than dimensions, the constructor recycles modes using modulo arithmetic. Default: `[ options.mode ]`.
-   **readonly**: `boolean` indicating whether an array should be **read-only**. Default: `false`.

The constructor supports the following `modes`:

-   **throw**: specifies that an `ndarray` instance should throw an error when an index exceeds array dimensions.
-   **normalize**: specifies that an `ndarray` instance should normalize negative indices and throw an error when an index exceeds array dimensions.
-   **wrap**: specifies that an `ndarray` instance should wrap around an index exceeding array dimensions using modulo arithmetic.
-   **clamp**: specifies that an `ndarray` instance should set an index exceeding array dimensions to either `0` (minimum index) or the maximum index.

By default, an `ndarray` instance **throws** when provided an index which exceeds array dimensions. To support alternative indexing behavior, set the `mode` option, which will affect all public methods for getting and setting array elements.

```javascript
var opts = {
    'mode': 'clamp'
};

// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order, opts );
// returns <ndarray>

// Attempt to access an out-of-bounds linear index (clamped):
var v = arr.iget( 10 );
// returns 4.0
```

By default, the `mode` option is applied to subscripts which exceed array dimensions. To specify behavior for each dimension, set the `submode` option.

```javascript
var opts = {
    'submode': [ 'wrap', 'clamp' ]
};

// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ];
var shape = [ 2, 2, 2 ];
var order = 'row-major';
var strides = [ 4, 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order, opts );
// returns <ndarray>

// Attempt to access out-of-bounds subscripts:
var v = arr.get( -2, 10, -1 ); // linear index: 3
// returns 4.0
```

* * *

### Properties

<a name="static-prop-name"></a>

#### ndarray.name

String value of the ndarray constructor name.

```javascript
var str = ndarray.name;
// returns 'ndarray'
```

<a name="prop-byte-length"></a>

#### ndarray.prototype.byteLength

Size (in bytes) of the array (if known).

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

// Specify the array configuration:
var buffer = new Float64Array( [ 1.0, 2.0, 3.0, 4.0 ] );
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'float64', buffer, shape, strides, offset, order );

// Get the byte length:
var nbytes = arr.byteLength;
// returns 32
```

If unable to determine the size of the array, the property value is `null`.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Get the byte length:
var nbytes = arr.byteLength;
// returns null
```

<a name="prop-bytes-per-element"></a>

#### ndarray.prototype.BYTES_PER_ELEMENT

Size (in bytes) of each array element (if known).

```javascript
var Float32Array = require( '@stdlib/array-float32' );

// Specify the array configuration:
var buffer = new Float32Array( [ 1.0, 2.0, 3.0, 4.0 ] );
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'float32', buffer, shape, strides, offset, order );

// Get the number of bytes per element:
var nbytes = arr.BYTES_PER_ELEMENT;
// returns 4
```

If size of each array element is unknown, the property value is `null`.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Get the number of bytes per element:
var nbytes = arr.BYTES_PER_ELEMENT;
// returns null
```

<a name="prop-data"></a>

#### ndarray.prototype.data

A reference to the underlying data buffer.

```javascript
var Int8Array = require( '@stdlib/array-int8' );

// Specify the array configuration:
var buffer = new Int8Array( [ 1, 2, 3, 4 ] );
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'int8', buffer, shape, strides, offset, order );

// Get the buffer reference:
var d = arr.data;
// returns <Int8Array>[ 1, 2, 3, 4 ]

var bool = ( d === buffer );
// returns true
```

<a name="prop-dtype"></a>

#### ndarray.prototype.dtype

Underlying [data type][@stdlib/ndarray/dtypes].

```javascript
var Uint8Array = require( '@stdlib/array-uint8' );

// Specify the array configuration:
var buffer = new Uint8Array( [ 1, 2, 3, 4 ] );
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ -2, 1 ];
var offset = 2;

// Create a new ndarray:
var arr = ndarray( 'uint8', buffer, shape, strides, offset, order );

// Get the underlying data type:
var dtype = arr.dtype;
// returns 'uint8'
```

<a name="prop-flags"></a>

#### ndarray.prototype.flags

Meta information, such as information regarding the memory layout of the array. The returned object has the following properties:

-   **ROW_MAJOR_CONTIGUOUS**: boolean indicating if an array is row-major contiguous.
-   **COLUMN_MAJOR_CONTIGUOUS**: boolean indicating if an array is column-major contiguous.
-   **READONLY**: boolean indicating whether an array is **read-only**.

An array is contiguous if (1) an array is compatible with being stored in a single memory segment and (2) each array element is adjacent to the next array element. Note that an array can be both row-major contiguous and column-major contiguous at the same time (e.g., if an array is a 1-dimensional ndarray with `strides = [1]`).

```javascript
var Int32Array = require( '@stdlib/array-int32' );

// Specify the array configuration:
var buffer = new Int32Array( [ 1, 2, 3, 4 ] );
var shape = [ 2, 2 ];
var order = 'column-major';
var strides = [ 1, 2 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'int32', buffer, shape, strides, offset, order );

// Get the array flags:
var flg = arr.flags;
// returns {...}
```

<a name="prop-length"></a>

#### ndarray.prototype.length

Number of array elements.

```javascript
var Uint16Array = require( '@stdlib/array-uint16' );

// Specify the array configuration:
var buffer = new Uint16Array( [ 1, 2, 3, 4 ] );
var shape = [ 2, 2 ];
var order = 'column-major';
var strides = [ -1, -2 ];
var offset = 3;

// Create a new ndarray:
var arr = ndarray( 'uint16', buffer, shape, strides, offset, order );

// Get the array length:
var len = arr.length;
// returns 4
```

<a name="prop-ndims"></a>

#### ndarray.prototype.ndims

Number of dimensions.

```javascript
var Uint8ClampedArray = require( '@stdlib/array-uint8c' );

// Specify the array configuration:
var buffer = new Uint8ClampedArray( [ 1, 2, 3, 4 ] );
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ -2, -1 ];
var offset = 3;

// Create a new ndarray:
var arr = ndarray( 'uint8c', buffer, shape, strides, offset, order );

// Get the number of dimensions:
var ndims = arr.ndims;
// returns 2
```

<a name="prop-offset"></a>

#### ndarray.prototype.offset

Index offset which specifies the `buffer` index at which to start iterating over array elements.

```javascript
var Int16Array = require( '@stdlib/array-int16' );

// Specify the array configuration:
var buffer = new Int16Array( [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ] );
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ -2, -1 ];
var offset = 10;

// Create a new ndarray:
var arr = ndarray( 'int16', buffer, shape, strides, offset, order );

// Get the index offset:
var o = arr.offset;
// returns 10
```

<a name="prop-order"></a>

#### ndarray.prototype.order

Array order. The array order is either row-major (C-style) or column-major (Fortran-style).

```javascript
var Uint32Array = require( '@stdlib/array-uint32' );

// Specify the array configuration:
var buffer = new Uint32Array( [ 1, 2, 3, 4 ] );
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'uint32', buffer, shape, strides, offset, order );

// Get the array order:
var ord = arr.order;
// returns 'row-major'
```

<a name="prop-shape"></a>

#### ndarray.prototype.shape

Returns a copy of the array shape.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 2;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Get the array shape:
var dims = arr.shape;
// returns [ 2, 2 ]
```

<a name="prop-strides"></a>

#### ndarray.prototype.strides

Returns a copy of the array strides which specify how to access data along corresponding array dimensions.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0 ];
var shape = [ 2, 2 ];
var order = 'column-major';
var strides = [ -1, 2 ];
var offset = 1;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Get the array strides:
var s = arr.strides;
// returns [ -1, 2 ]
```

* * *

### Methods

<a name="method-get"></a>

#### ndarray.prototype.get( i, j, k, ... )

Returns an array element specified according to provided subscripts. The number of provided subscripts must **equal** the number of dimensions.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 2;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Get the element located at (1,1):
var v = arr.get( 1, 1 );
// returns 6.0
```

<a name="method-iget"></a>

#### ndarray.prototype.iget( idx )

Returns an array element located at a specified linear index.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 2;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Get the element located at index 3:
var v = arr.iget( 3 );
// returns 6.0
```

For zero-dimensional arrays, the input argument is ignored and, for clarity, should **not** be provided.

<a name="method-set"></a>

#### ndarray.prototype.set( i, j, k, ..., v )

Sets an array element specified according to provided subscripts. The number of provided subscripts must **equal** the number of dimensions.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Set the element located at (1,1):
arr.set( 1, 1, 40.0 );
var v = arr.get( 1, 1 );
// returns 40.0

// Get the underlying buffer:
var d = arr.data;
// returns [ 1.0, 2.0, 3.0, 40.0 ]
```

The method returns the `ndarray` instance. If an array is **read-only**, the method raises an exception.

<a name="method-iset"></a>

#### ndarray.prototype.iset( idx, v )

Sets an array element located at a specified linear index.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0 ];
var shape = [ 2, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 0;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Set the element located at index 3:
arr.iset( 3, 40.0 );
var v = arr.iget( 3 );
// returns 40.0

// Get the underlying buffer:
var d = arr.data;
// returns [ 1.0, 2.0, 3.0, 40.0 ]
```

For zero-dimensional arrays, the first, and **only**, argument should be the value `v` to set.

The method returns the `ndarray` instance. If an array is **read-only**, the method raises an exception.

<a name="method-to-string"></a>

#### ndarray.prototype.toString()

Serializes an `ndarray` as a `string`.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ];
var shape = [ 3, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 2;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Serialize to a string:
var str = arr.toString();
// returns "ndarray( 'generic', [ 3, 4, 5, 6, 7, 8 ], [ 3, 2 ], [ 2, 1 ], 0, 'row-major' )"
```

The method does **not** serialize data outside of the buffer region defined by the array configuration.

<a name="method-to-json"></a>

#### ndarray.prototype.toJSON()

Serializes an `ndarray` as a [JSON][json] `object`. `JSON.stringify()` implicitly calls this method when stringifying an `ndarray` instance.

```javascript
// Specify the array configuration:
var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ];
var shape = [ 3, 2 ];
var order = 'row-major';
var strides = [ 2, 1 ];
var offset = 2;

// Create a new ndarray:
var arr = ndarray( 'generic', buffer, shape, strides, offset, order );

// Serialize to JSON:
var o = arr.toJSON();
// returns { 'type': 'ndarray', 'dtype': 'generic', 'flags': {...}, 'offset': 0, 'order': 'row-major', 'shape': [ 3, 2 ], 'strides': [ 2, 1 ], 'data': [ 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] }
```

The method does **not** serialize data outside of the buffer region defined by the array configuration.

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## Notes

-   To create a zero-dimensional array, provide an empty `shape` and a single `strides` element equal to `0`. The `order` can be either `row-major` or `column-major` and has no effect on data storage or access.

    ```javascript
    var buffer = [ 1 ];
    var shape = [];
    var order = 'row-major';
    var strides = [ 0 ];
    var offset = 0;

    // Create a new zero-dimensional array:
    var arr = ndarray( 'generic', buffer, shape, strides, offset, order );
    // returns <ndarray>
    ```

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

* * *

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var Float32Array = require( '@stdlib/array-float32' );
var ndarray = require( '@stdlib/ndarray-ctor' );

// Create a data buffer:
var buffer = new Float32Array( (3*3*3*3) + 100 );

// Specify the array shape:
var shape = [ 3, 3, 3, 3 ];

// Specify the array strides:
var strides = [ 27, 9, 3, 1 ];

// Specify the index offset:
var offset = 4;

// Specify the order:
var order = 'row-major'; // C-style

// Create a new ndarray:
var arr = ndarray( 'float32', buffer, shape, strides, offset, order );

// Retrieve an array value:
var v = arr.get( 1, 2, 1, 2 );
// returns 0.0

// Set an array value:
arr.set( 1, 2, 1, 2, 10.0 );

// Retrieve the array value:
v = arr.get( 1, 2, 1, 2 );
// returns 10.0

// Serialize the array as a string:
var str = arr.toString();
// returns "ndarray( 'float32', new Float32Array( [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ] ), [ 3, 3, 3, 3 ], [ 27, 9, 3, 1 ], 0, 'row-major' )"

// Serialize the array as JSON:
str = JSON.stringify( arr.toJSON() );
// e.g., returns '{"type":"ndarray","dtype":"float32","flags":{"READONLY":false},"order":"row-major","shape":[3,3,3,3],"strides":[27,9,3,1],"data":[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,10,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]}'
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

<!-- /.intro -->

<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
#include "stdlib/ndarray/ctor.h"
```

#### ndarray

Structure holding ndarray data.

```c
#include "stdlib/ndarray/dtypes.h"
#include "stdlib/ndarray/index_modes.h"
#include "stdlib/ndarray/orders.h"
#include "stdlib/ndarray/base/bytes_per_element.h"
#include <stdint.h>

struct ndarray {
    // Underlying data type:
    int16_t dtype;

    // Pointer to the underlying byte array:
    uint8_t *data;

    // Number of array dimensions:
    int64_t ndims;

    // Array shape (dimensions):
    int64_t *shape;

    // Array strides (in bytes) specifying how to iterate over a strided array:
    int64_t *strides;

    // Byte offset which specifies the location at which to start iterating over array elements:
    int64_t offset;

    // Array order (either row-major (C-style) or column-major (Fortran-style)):
    int8_t order;

    // Mode specifying how to handle indices which exceed array dimensions:
    int8_t imode;

    // Number of subscript modes:
    int64_t nsubmodes;

    // Mode(s) specifying how to handle subscripts which exceed array dimensions on a per dimension basis:
    int8_t *submodes;

    // Number of array elements:
    int64_t length;

    // Size in bytes:
    int64_t byteLength;

    // Number of bytes per element (i.e., item size):
    int64_t BYTES_PER_ELEMENT;

    // Bit mask providing information regarding the memory layout of the array (e.g., see macros):
    int64_t flags;
};
```

#### STDLIB_NDARRAY_ROW_MAJOR_CONTIGUOUS_FLAG

Macro defining a flag indicating whether an ndarray is row-major (C-style) contiguous.

```c
#define STDLIB_NDARRAY_ROW_MAJOR_CONTIGUOUS_FLAG 0x0001
```

Notes:

-   Row-major order indicates that the last ndarray index varies the fastest.
-   Contiguous means that an ndarray is compatible with being stored in a single memory segment and that ndarray elements are adjacent to each other in memory.
-   `strides` array is in reverse order to that of column-major order.
-   An ndarray can be both row-major and column-major contiguous (e.g., if an ndarray is one-dimensional).

#### STDLIB_NDARRAY_COLUMN_MAJOR_CONTIGUOUS_FLAG

Macro defining a flag indicating whether an ndarray is column-major (Fortran-style) contiguous.

```c
#define STDLIB_NDARRAY_COLUMN_MAJOR_CONTIGUOUS_FLAG 0x0002
```

Notes:

-   Column-major order indicates that the first ndarray index varies the fastest.
-   Contiguous means that an ndarray is compatible with being stored in a single memory segment and that ndarray elements are adjacent to each other in memory.
-   `strides` array is in reverse order to that of row-major order.
-   An ndarray can be both row-major and column-major contiguous (e.g., if an ndarray is one-dimensional).

* * *

<!-- NOTE: keep functions in alphabetical order -->

#### stdlib_ndarray_allocate( dtype, \*data, ndims, \*shape, \*strides, offset, order, imode, nsubmodes, \*submodes )

Returns a pointer to a dynamically allocated ndarray.

```c
#include "stdlib/ndarray/ctor.h"
#include "stdlib/ndarray/dtypes.h"
#include "stdlib/ndarray/index_modes.h"
#include "stdlib/ndarray/orders.h"
#include "stdlib/ndarray/base/bytes_per_element.h"
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>

// Specify the underlying data type:
enum STDLIB_NDARRAY_DTYPE dtype = STDLIB_NDARRAY_FLOAT64;

// Create an underlying byte array:
uint8_t buffer[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

// Specify the number of array dimensions:
int64_t ndims = 1;

// Specify the array shape:
int64_t shape[] = { 3 }; // vector consisting of 3 doubles

// Specify the array strides:
int64_t strides[] = { STDLIB_NDARRAY_FLOAT64_BYTES_PER_ELEMENT };

// Specify the byte offset:
int64_t offset = 0;

// Specify the array order (note: this does not matter for a 1-dimensional array):
enum STDLIB_NDARRAY_ORDER order = STDLIB_NDARRAY_ROW_MAJOR;

// Specify the index mode:
enum STDLIB_NDARRAY_INDEX_MODE imode = STDLIB_NDARRAY_INDEX_ERROR;

// Specify the subscript index modes:
int8_t submodes[] = { STDLIB_NDARRAY_INDEX_ERROR };
int64_t nsubmodes = 1;

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( dtype, buffer, ndims, shape, strides, offset, order, imode, nsubmodes, submodes );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **dtype**: `[in] int16_t` [data type][@stdlib/ndarray/dtypes].
-   **data**: `[in] uint8_t*` pointer to the underlying byte array.
-   **ndims**: `[in] int64_t` number of dimensions.
-   **shape**: `[in] int64_t*` array shape (i.e., dimensions).
-   **strides**: `[in] int64_t*` array strides (in bytes).
-   **offset**: `[in] int64_t` byte offset specifying the location of the first element.
-   **order**: `[in] int8_t` specifies whether an array is [row-major][@stdlib/ndarray/orders] (C-style) or [column-major][@stdlib/ndarray/orders] (Fortran-style).
-   **imode**: `[in] int8_t` specifies the [index mode][@stdlib/ndarray/index-modes] (i.e., how to handle indices which exceed array dimensions).
-   **nsubmodes**: `[in] int64_t` number of subscript modes.
-   **submodes**: `[in] int8_t*` specifies how to handle subscripts which [exceed][@stdlib/ndarray/index-modes] array dimensions on a per dimension basis (if provided fewer submodes than dimensions, submodes are recycled using modulo arithmetic).

```c
struct ndarray * stdlib_ndarray_allocate( int16_t dtype, uint8_t *data, int64_t ndims, int64_t *shape, int64_t *strides, int64_t offset, int8_t order, int8_t imode, int64_t nsubmodes, int8_t *submodes );
```

Notes:

-   The user is responsible for freeing the allocated memory.
-   To allocate a zero-dimensional ndarray, provide a `shape` argument equal to a null pointer, an `ndims` argument equal to `0`, and a `strides` argument consisting of a single element equal to `0`. The `order` argument can be either row-major or column-major and has no effect on data storage or access.

#### stdlib_ndarray_byte_length( \*arr )

Returns the size of an ndarray (in bytes).

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the ndarray size:
int64_t N = stdlib_ndarray_byte_length( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_byte_length( const struct ndarray *arr );
```

#### stdlib_ndarray_byte_length_per_element( \*arr )

Returns the number of bytes per ndarray element.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the number of bytes per element:
int64_t nb = stdlib_ndarray_byte_length_per_element( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_byte_length_per_element( const struct ndarray *arr );
```

#### stdlib_ndarray_data( \*arr )

Returns a pointer to an ndarray's underlying byte array.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the underlying byte array:
uint8_t *data = stdlib_ndarray_data( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
uint8_t * stdlib_ndarray_data( const struct ndarray *arr );
```

#### stdlib_ndarray_dimension( \*arr, i )

Returns an ndarray dimension.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve a dimension:
int64_t dim = stdlib_ndarray_dimension( x, 0 );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **i**: `[in] int64_t` dimension index.

```c
int64_t stdlib_ndarray_dimension( const struct ndarray *arr, const int64_t i );
```

Notes:

-   The function does perform bounds checking for the dimension index.
-   If an input ndarray is zero-dimensional, the function always returns `-1`.

#### stdlib_ndarray_disable_flags( \*arr, flags )

Disables specified ndarray flags.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Disables specified ndarray flags:
int8_t status = stdlib_ndarray_disable_flags( x, STDLIB_NDARRAY_ROW_MAJOR_CONTIGUOUS_FLAG );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **flags**: `[in] int64_t` bit mask to disable flags.

The function returns a status code of `0` if able to successfully disable flags.

```c
int8_t stdlib_ndarray_disable_flags( const struct ndarray *arr, const int64_t flags );
```

Notes:

-   The function does not perform any sanity checks and **assumes** the user knows what s/he is doing.

#### stdlib_ndarray_dtype( \*arr )

Returns the data type of an ndarray.

```c
#include "stdlib/ndarray/ctor.h"
#include "stdlib/ndarray/dtypes.h"
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the dtype:
enum STDLIB_NDARRAY_DTYPE dtype = stdlib_ndarray_dtype( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int16_t stdlib_ndarray_dtype( const struct ndarray *arr );
```

#### stdlib_ndarray_enable_flags( \*arr, flags )

Enables specified ndarray flags.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Enables specified ndarray flags:
int8_t status = stdlib_ndarray_enable_flags( x, STDLIB_NDARRAY_ROW_MAJOR_CONTIGUOUS_FLAG );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **flags**: `[in] int64_t` bit mask to enable flags.

The function returns a status code of `0` if able to successfully enable flags.

```c
int8_t stdlib_ndarray_enable_flags( const struct ndarray *arr, const int64_t flags );
```

Notes:

-   The function does not perform any sanity checks and **assumes** the user knows what s/he is doing.

#### stdlib_ndarray_flags( \*arr )

Returns ndarray flags as a single integer value.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the ndarray flags:
int64_t flags = stdlib_ndarray_flags( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_flags( const struct ndarray *arr );
```

#### stdlib_ndarray_free( \*arr )

Frees an ndarray's allocated memory.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
void stdlib_ndarray_free( struct ndarray *arr );
```

#### stdlib_ndarray_has_flags( \*arr, flags )

Tests whether an ndarray has specified flags enabled.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Test whether an ndarray is row-major contiguous:
int8_t out = stdlib_ndarray_flags( x, STDLIB_NDARRAY_ROW_MAJOR_CONTIGUOUS_FLAG );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **flags**: `[in] int64_t` bit mask specifying flags to test against.

The function returns `1` if flags are set and `0` otherwise.

```c
int8_t stdlib_ndarray_has_flags( const struct ndarray *arr, const int64_t flags );
```

#### stdlib_ndarray_index_mode( \*arr )

Returns the index mode of an ndarray.

```c
#include "stdlib/ndarray/ctor.h"
#include "stdlib/ndarray/index_modes.h"
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the index mode:
enum STDLIB_NDARRAY_INDEX_MODE imode = stdlib_ndarray_index_mode( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int8_t stdlib_ndarray_index_mode( const struct ndarray *arr );
```

#### stdlib_ndarray_length( \*arr )

Returns the number of elements in an ndarray.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the number of elements:
int64_t N = stdlib_ndarray_length( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_length( const struct ndarray *arr );
```

#### stdlib_ndarray_ndims( \*arr )

Returns the number of ndarray dimensions.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the number of dimensions:
int64_t ndims = stdlib_ndarray_ndims( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_ndims( const struct ndarray *arr );
```

#### stdlib_ndarray_nsubmodes( \*arr )

Returns the number of ndarray subscript modes.

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the number of index modes:
int64_t n = stdlib_ndarray_nsubmodes( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_nsubmodes( const struct ndarray *arr );
```

#### stdlib_ndarray_offset( \*arr )

Returns an ndarray index offset (in bytes).

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the index offset:
int64_t offset = stdlib_ndarray_offset( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_offset( const struct ndarray *arr );
```

#### stdlib_ndarray_offset_elements( \*arr )

Returns an ndarray index offset (in elements).

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the index offset:
int64_t offset = stdlib_ndarray_offset_elements( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t stdlib_ndarray_offset_elements( const struct ndarray *arr );
```

Notes:

-   The function assumes that the ndarray is **aligned** (i.e., the index offset in bytes is a multiple of the number of bytes per ndarray element).

#### stdlib_ndarray_order( \*arr )

Returns the order of an ndarray.

```c
#include "stdlib/ndarray/ctor.h"
#include "stdlib/ndarray/orders.h"
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the order:
enum STDLIB_NDARRAY_ORDER order = stdlib_ndarray_order( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int8_t stdlib_ndarray_order( const struct ndarray *arr );
```

#### stdlib_ndarray_shape( \*arr )

Returns a pointer to an array containing an ndarray shape (dimensions).

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the shape:
int64_t *shape = stdlib_ndarray_shape( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t * stdlib_ndarray_shape( const struct ndarray *arr );
```

Notes:

-   If an input ndarray is zero-dimensional, the function returns a null pointer.

#### stdlib_ndarray_stride( \*arr, i )

Returns an ndarray stride (in bytes).

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve a stride:
int64_t s = stdlib_ndarray_stride( x, 0 );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **i**: `[in] int64_t` dimension index.

```c
int64_t stdlib_ndarray_stride( const struct ndarray *arr, const int64_t i );
```

Notes:

-   The function does **not** perform bounds checking for the dimension index.

#### stdlib_ndarray_stride_elements( \*arr, i )

Returns an ndarray stride (in elements).

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve a stride:
int64_t s = stdlib_ndarray_stride_elements( x, 0 );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **i**: `[in] int64_t` dimension index.

```c
int64_t stdlib_ndarray_stride_elements( const struct ndarray *arr, const int64_t i );
```

Notes:

-   The function does **not** perform bounds checking for the dimension index.
-   The function assumes that the ndarray is **aligned** (i.e., the stride in bytes is a multiple of the number of bytes per ndarray element).

#### stdlib_ndarray_strides( \*arr )

Returns a pointer to an array containing ndarray strides (in bytes).

```c
#include "stdlib/ndarray/ctor.h"
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the strides:
int64_t *strides = stdlib_ndarray_strides( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int64_t * stdlib_ndarray_strides( const struct ndarray *arr );
```

#### stdlib_ndarray_submode( \*arr, i )

Returns an ndarray subscript mode.

```c
#include "stdlib/ndarray/ctor.h"
#include "stdlib/ndarray/index_modes.h"
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve an index mode:
enum STDLIB_NDARRAY_INDEX_MODE mode = stdlib_ndarray_submode( x, 0 );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **i**: `[in] int64_t` dimension index.

```c
int8_t stdlib_ndarray_submode( const struct ndarray *arr, const int64_t i );
```

Notes:

-   If an ndarray has fewer subscript modes than dimensions, modes are recycled using modulo arithmetic.
-   The function does not perform bounds checking for the dimension index.

#### stdlib_ndarray_submodes( \*arr )

Returns ndarray subscript modes.

```c
#include "stdlib/ndarray/ctor.h"
#include "stdlib/ndarray/index_modes.h"
#include <stdlib.h>
#include <stdio.h>

// ...

// Create an ndarray:
struct ndarray *x = stdlib_ndarray_allocate( ... );
if ( x == NULL ) {
    fprintf( stderr, "Error allocating memory.\n" );
    exit( 1 );
}

// ...

// Retrieve the index subscript modes:
int8_t *modes = stdlib_ndarray_submodes( x );

// ...

// Free allocated memory:
stdlib_ndarray_free( x );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.

```c
int8_t * stdlib_ndarray_submodes( const struct ndarray *arr );
```

* * *

#### stdlib_ndarray_get( \*arr, \*sub, \*out )

Returns an ndarray data element.

```c
int8_t stdlib_ndarray_get( const struct ndarray *arr, const int64_t *sub, void *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] void *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function requires a `void` pointer for the output address `out` in order to provide a generic API supporting ndarrays having different data types.

#### stdlib_ndarray_get_float64( \*arr, \*sub, \*out )

Returns a double-precision floating-point ndarray data element.

```c
int8_t stdlib_ndarray_get_float64( const struct ndarray *arr, const int64_t *sub, double *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] double *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_float32( \*arr, \*sub, \*out )

Returns a single-precision floating-point ndarray data element.

```c
int8_t stdlib_ndarray_get_float32( const struct ndarray *arr, const int64_t *sub, float *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] float *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_uint64( \*arr, \*sub, \*out )

Returns an unsigned 64-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_uint64( const struct ndarray *arr, const int64_t *sub, uint64_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] uint64_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_int64( \*arr, \*sub, \*out )

Returns a signed 64-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_int64( const struct ndarray *arr, const int64_t *sub, int64_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] int64_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_uint32( \*arr, \*sub, \*out )

Returns an unsigned 32-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_uint32( const struct ndarray *arr, const int64_t *sub, uint32_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] uint32_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_int32( \*arr, \*sub, \*out )

Returns a signed 32-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_int32( const struct ndarray *arr, const int64_t *sub, int32_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] int32_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_uint16( \*arr, \*sub, \*out )

Returns an unsigned 16-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_uint16( const struct ndarray *arr, const int64_t *sub, uint16_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] uint16_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_int16( \*arr, \*sub, \*out )

Returns a signed 16-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_int16( const struct ndarray *arr, const int64_t *sub, int16_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] int16_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_uint8( \*arr, \*sub, \*out )

Returns an unsigned 8-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_uint8( const struct ndarray *arr, const int64_t *sub, uint8_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] uint8_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_int8( \*arr, \*sub, \*out )

Returns a signed 8-bit integer ndarray data element.

```c
int8_t stdlib_ndarray_get_int8( const struct ndarray *arr, const int64_t *sub, int8_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] int8_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_complex128( \*arr, \*sub, \*out )

Returns a double-precision complex floating-point ndarray data element.

```c
int8_t stdlib_ndarray_get_complex128( const struct ndarray *arr, const int64_t *sub, stdlib_complex128_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] stdlib_complex128_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_complex64( \*arr, \*sub, \*out )

Returns a single-precision complex floating-point ndarray data element.

```c
int8_t stdlib_ndarray_get_complex64( const struct ndarray *arr, const int64_t *sub, stdlib_complex64_t *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] stdlib_complex64_t *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

#### stdlib_ndarray_get_bool( \*arr, \*sub, \*out )

Returns a boolean ndarray data element.

```c
int8_t stdlib_ndarray_get_bool( const struct ndarray *arr, const int64_t *sub, bool *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.
-   **out**: `[out] bool *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.

* * *

#### stdlib_ndarray_get_ptr( \*arr, \*sub )

Returns a pointer to an ndarray data element in the underlying byte array.

```c
uint8_t * stdlib_ndarray_get_ptr( const struct ndarray *arr, const int64_t *sub );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **sub**: `[in] int64_t *` ndarray subscripts.

#### stdlib_ndarray_get_ptr_value( \*arr, \*idx, \*out )

Returns an ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_value( const struct ndarray *arr, const uint8_t *idx, void *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray *` input ndarray.
-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] void *` output address.

Notes:

-   The function does **not** perform bounds checking and **assumes** you know what you are doing.
-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function requires a `void` pointer for the output address `out` in order to provide a generic API supporting ndarrays having different data types.

#### stdlib_ndarray_get_ptr_float64( \*idx, \*out )

Returns a double-precision floating-point ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_float64( const uint8_t *idx, double *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] double *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_float32( \*idx, \*out )

Returns a single-precision floating-point ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_float32( const uint8_t *idx, float *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] float *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_uint64( \*idx, \*out )

Returns an unsigned 64-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_uint64( const uint8_t *idx, uint64_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] uint64_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_int64( \*idx, \*out )

Returns a signed 64-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_int64( const uint8_t *idx, int64_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] int64_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_uint32( \*idx, \*out )

Returns an unsigned 32-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_uint32( const uint8_t *idx, uint32_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] uint32_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_int32( \*idx, \*out )

Returns a signed 32-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_int32( const uint8_t *idx, int32_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] int32_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_uint16( \*idx, \*out )

Returns an unsigned 16-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_uint16( const uint8_t *idx, uint16_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] uint16_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_int16( \*idx, \*out )

Returns a signed 16-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_int16( const uint8_t *idx, int16_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] int16_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_uint8( \*idx, \*out )

Returns an unsigned 8-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_uint8( const uint8_t *idx, uint8_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] uint8_t *` output address.

Notes:

-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_int8( \*idx, \*out )

Returns a signed 8-bit integer ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_int8( const uint8_t *idx, int8_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] int8_t *` output address.

Notes:

-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_complex128( \*idx, \*out )

Returns a double-precision complex floating-point ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_complex128( const uint8_t *idx, stdlib_complex128_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] stdlib_complex128_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_complex64( \*idx, \*out )

Returns a single-precision complex floating-point ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_complex64( const uint8_t *idx, stdlib_complex64_t *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] stdlib_complex64_t *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

#### stdlib_ndarray_get_ptr_bool( \*idx, \*out )

Returns a boolean ndarray data element specified by a byte array pointer.

```c
int8_t stdlib_ndarray_get_ptr_bool( const uint8_t *idx, bool *out );
```

The function accepts the following arguments:

-   **idx**: `[in] uint8_t *` byte array pointer to an ndarray data element.
-   **out**: `[out] bool *` output address.

Notes:

-   The function has no way of determining whether `idx` actually points to a compatible memory address. Accordingly, accessing **unowned** memory is possible, and this function **assumes** you know what you are doing.
-   The function always returns `0`.

* * *

#### stdlib_ndarray_iget( \*arr, idx, \*out )

Returns an ndarray data element located at a specified linear index.

```c
int8_t stdlib_ndarray_iget( const struct ndarray *arr, const int64_t idx, void *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **idx**: `[in] int64_t` linear view index.
-   **out**: `[out] void *` output address.

Notes:

-   The function returns `-1` if unable to get an element and `0` otherwise.
-   The function requires a `void` pointer for the output address `out` in order to provide a generic API supporting ndarrays having different data types.
-   The function places the burden on the user to ensure that the output address is compatible with the data type of input ndarray data elements.
-   For zero-dimensional arrays, the function returns the first (and only) indexed element, regardless of the value of `idx`.

#### stdlib_ndarray_iget_float64( \*arr, idx, \*out )

Returns a double-precision floating-point ndarray data element located at a specified linear index.

```c
int8_t stdlib_ndarray_iget_float64( const struct ndarray *arr, const int64_t idx, double *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **idx**: `[in] int64_t` linear view index.
-   **out**: `[out] double *` output address.

Notes:

-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.
-   The function returns `-1` if unable to get an element and `0` otherwise.
-   For zero-dimensional arrays, the function returns the first (and only) indexed element, regardless of the value of `idx`.

#### stdlib_ndarray_iget_float32( \*arr, idx, \*out )

Returns a single-precision floating-point ndarray data element located at a specified linear index.

```c
int8_t stdlib_ndarray_iget_float32( const struct ndarray *arr, const int64_t idx, float *out );
```

The function accepts the following arguments:

-   **arr**: `[in] struct ndarray*` input ndarray.
-   **idx**: `[in] int64_t` linear view index.
-   **out**: `[out] float *` output address.

Notes:

-   The function does **not** verify that the output address type matches the underlying input ndarray data type and **assumes** that you know what you are doing.
-   The function returns `-1` if unable to get an element and `0` otherwise.
-   For zero-dimensional arrays, the function returns the first (and only) indexed element, regardless of the value of `idx`.

#### stdlib_ndarray_iget_uint64( \*arr, idx, \*out )

Returns an unsigned 64-bit integer ndarray data element located at a specified linear index.

```c
int8_t stdlib_ndarray_iget_uint64( const struct ndarr