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# flattenShape

> Flatten a shape to a specified depth.

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## 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.

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## 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 );
```

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* * *

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## C APIs

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</section>

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### 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
#include <stdint.h>

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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### 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" );
}
```

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</section>

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</section>

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