npm package: @stdlib/ndarray-base-flatten-shape
Description: Flatten a shape to a specified depth.
Author: The Stdlib Authors
Latest version: 0.1.1

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# flattenShape

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> Flatten a shape to a specified depth.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/ndarray-base-flatten-shape
```

</section>

<section class="usage">

## Usage

```javascript
var flattenShape = require( '@stdlib/ndarray-base-flatten-shape' );
```

#### flattenShape( shape, depth )

Flattens a shape to a specified depth.

```javascript
var sh = flattenShape( [ 3, 2 ], 1 );
// returns [ 6 ]
```

The function accepts the following parameters:

-   **shape**: array shape.
-   **depth**: maximum depth to flatten.

#### flattenShape.assign( shape, depth, out )

Flattens a shape to a specified depth and assigns results to a provided output array.

```javascript
var sh = [ 0 ];

var out = flattenShape.assign( [ 3, 2 ], 1, sh );
// returns [ 6 ]

var bool = ( sh === out );
// returns true
```

The function accepts the following parameters:

-   **shape**: array shape.
-   **depth**: maximum depth to flatten.
-   **out**: output array.

</section>

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<section class="notes">

</section>

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<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var zip = require( '@stdlib/array-base-zip' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var flattenShape = require( '@stdlib/ndarray-base-flatten-shape' );

var opts = {
    'dtype': 'int32'
};
var d1 = discreteUniform( 100, 1, 10, opts );
var d2 = discreteUniform( d1.length, 1, 10, opts );
var d3 = discreteUniform( d1.length, 1, 10, opts );
var d4 = discreteUniform( d1.length, 1, 10, opts );

var depths = discreteUniform( d1.length, 0, 3, opts );
var shapes = zip( [ d1, d2, d3, d4 ] );

logEachMap( 'shape: (%s). depth: %d. flattened: (%s).', shapes, depths, flattenShape );
```

</section>

<!-- /.examples -->

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* * *

<section class="c">

## C APIs

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<section class="usage">

### Usage

```c
#include "stdlib/ndarray/base/flatten_shape.h"
```

#### stdlib_ndarray_flatten_shape( ndims, \*shape, depth, \*out )

Flattens a shape to a specified depth.

```c
const int64_t ndims = 3;
const int64_t shape[] = { 2, 3, 10 };
int64_t out[ 1 ];

stdlib_ndarray_flatten_shape( ndims, shape, 2, out );
```

The function accepts the following arguments:

-   **ndims**: `[in] int64_t` number of dimensions.
-   **shape**: `[in] int64_t*` array shape (dimensions).
-   **depth**: `[in] int64_t` maximum depth to flatten.
-   **out**: `[out] int64_t*` output array.

```c
int8_t stdlib_ndarray_flatten_shape( const int64_t ndims, const int64_t *shape, const int64_t depth, int64_t *out );
```

</section>

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</section>

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<section class="examples">

### Examples

```c
#include "stdlib/ndarray/base/flatten_shape.h"
#include <stdio.h>
#include <inttypes.h>

int main( void ) {
    const int64_t shape[] = { 2, 3, 4, 10 };
    const int64_t ndims = 4;
    const int64_t depth = 2;
    int64_t out[ 2 ];

    stdlib_ndarray_flatten_shape( ndims, shape, depth, out );

    int i;
    printf( "shape = ( " );
    for ( i = 0; i < ndims-depth; i++ ) {
        printf( "%"PRId64"", out[ i ] );
        if ( i < ndims-depth-1 ) {
            printf( ", " );
        }
    }
    printf( " )\n" );
}
```

</section>

<!-- /.examples -->

</section>

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* * *

## Notice

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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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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