# includes
> Test whether an ndarray contains a specified value.
## Usage
```javascript
var includes = require( '@stdlib/ndarray/base/includes' );
```
#### includes( arrays )
Tests whether an ndarray contains a specified value.
```javascript
var Float64Array = require( '@stdlib/array/float64' );
// Create a data buffer:
var xbuf = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
// Define the shape of the input array:
var shape = [ 3, 1, 2 ];
// Define the array strides:
var sx = [ 4, 4, 1 ];
// Define the index offset:
var ox = 0;
// Create the input ndarray-like object:
var x = {
'dtype': 'float64',
'data': xbuf,
'shape': shape,
'strides': sx,
'offset': ox,
'order': 'row-major'
};
// Create the search element ndarray-like object:
var searchElement = {
'dtype': 'float64',
'data': new Float64Array( [ 6.0 ] ),
'shape': [],
'strides': [ 0 ],
'offset': 0,
'order': 'row-major'
};
// Perform reduction:
var out = includes( [ x, searchElement ] );
// returns true
```
The function accepts the following arguments:
- **arrays**: array-like object containing an input ndarray and a zero-dimensional search element ndarray.
Each provided ndarray should be an object with the following properties:
- **dtype**: data type.
- **data**: data buffer.
- **shape**: dimensions.
- **strides**: stride lengths.
- **offset**: index offset.
- **order**: specifies whether an ndarray is row-major (C-style) or column major (Fortran-style).
## Notes
- For very high-dimensional ndarrays which are non-contiguous, one should consider copying the underlying data to contiguous memory before performing the operation in order to achieve better performance.
## Examples
```javascript
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var ndarray2array = require( '@stdlib/ndarray/base/to-array' );
var includes = require( '@stdlib/ndarray/base/includes' );
var x = {
'dtype': 'generic',
'data': discreteUniform( 10, 0, 10, {
'dtype': 'generic'
}),
'shape': [ 5, 2 ],
'strides': [ 2, 1 ],
'offset': 0,
'order': 'row-major'
};
console.log( ndarray2array( x.data, x.shape, x.strides, x.offset, x.order ) );
var v = {
'dtype': x.dtype,
'data': [ 1 ],
'shape': [],
'strides': [ 0 ],
'offset': 0,
'order': x.order
};
console.log( 'Search element: %d', v.data[ 0 ] );
var out = includes( [ x, v ] );
console.log( out );
```
* * *
## C APIs
Character codes for data types:
- **x**: `bool` (boolean).
- **z**: `complex128` (double-precision floating-point complex number).
- **c**: `complex64` (single-precision floating-point complex number).
- **f**: `float32` (single-precision floating-point number).
- **d**: `float64` (double-precision floating-point number).
- **k**: `int16` (signed 16-bit integer).
- **i**: `int32` (signed 32-bit integer).
- **s**: `int8` (signed 8-bit integer).
- **t**: `uint16` (unsigned 16-bit integer).
- **u**: `uint32` (unsigned 32-bit integer).
- **b**: `uint8` (unsigned 8-bit integer).
Function name suffix naming convention:
```text
stdlib_ndarray_includes__[_as__]
```
For example,
```c
void stdlib_ndarray_includes_dd_x(...) {...}
```
is a function which accepts one double-precision floating-point input ndarray, a double-precision floating-point search element ndarray, and one boolean output ndarray.
TODO: document casting convention
### Usage
```c
#include "stdlib/ndarray/base/includes.h"
```
* * *
### Examples
```c
// TODO
```