npm package: @stdlib/ndarray-base-max-view-buffer-index
Description: Compute the maximum linear index in an underlying data buffer accessible to an array view.
Author: The Stdlib Authors
Latest version: 0.2.3

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# maxViewBufferIndex

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> Compute the maximum linear index in an underlying data buffer accessible to an array view.

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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-max-view-buffer-index
```

</section>

<section class="usage">

## Usage

```javascript
var maxViewBufferIndex = require( '@stdlib/ndarray-base-max-view-buffer-index' );
```

#### maxViewBufferIndex( shape, strides, offset )

Computes the maximum linear index in an underlying data buffer accessible to an array view.

```javascript
// Array shape:
var shape = [ 2, 2 ];

// Stride array:
var strides = [ 2, 1 ];

// Index offset which specifies the location of the first indexed value:
var offset = 0;

var idx = maxViewBufferIndex( shape, strides, offset );
// returns 3
```

</section>

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<section class="notes">

</section>

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<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var shape2strides = require( '@stdlib/ndarray-base-shape2strides' );
var strides2offset = require( '@stdlib/ndarray-base-strides2offset' );
var randu = require( '@stdlib/random-base-randu' );
var maxViewBufferIndex = require( '@stdlib/ndarray-base-max-view-buffer-index' );

var strides;
var offset;
var shape;
var idx;
var i;
var j;

shape = [ 0, 0, 0 ];

for ( i = 0; i < 100; i++ ) {
    // Generate a random array shape:
    shape[ 0 ] = discreteUniform( 1, 10 );
    shape[ 1 ] = discreteUniform( 1, 10 );
    shape[ 2 ] = discreteUniform( 1, 10 );

    // Generate strides:
    if ( randu() < 0.5 ) {
        strides = shape2strides( shape, 'row-major' );
    } else {
        strides = shape2strides( shape, 'column-major' );
    }
    j = discreteUniform( 0, shape.length-1 );
    strides[ j ] *= ( randu() < 0.5 ) ? -1 : 1;

    // Compute the index offset:
    offset = strides2offset( shape, strides );

    // Compute the maximum linear index:
    idx = maxViewBufferIndex( shape, strides, offset );
    console.log( 'Shape: %s. Strides: %s. Offset: %d. Max idx: %d.', shape.join( 'x' ), strides.join( ',' ), offset, idx );
}
```

</section>

<!-- /.examples -->

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* * *

<section class="c">

## C APIs

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<section class="usage">

### Usage

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

#### stdlib_ndarray_max_view_buffer_index( ndims, \*shape, \*strides, offset )

Computes the maximum linear index (in bytes) in an underlying data buffer accessible to an array view.

```c
#include <stdint.h>

int64_t ndims = 2;
int64_t shape[] = { 10, 10 };
int64_t strides[] = { 10, 1 };
int64_t offset = 0;

int64_t idx = stdlib_ndarray_max_view_buffer_index( ndims, shape, strides, offset );
// returns 99
```

The function accepts the following arguments:

-   **ndims**: `[in] int64_t` number of dimensions.
-   **shape**: `[in] int64_t*` array shape (dimensions).
-   **strides**: `[in] int64_t*` array strides (in bytes).
-   **offset**: `[in] int64_t` index offset.

```c
int64_t stdlib_ndarray_max_view_buffer_index( const int64_t ndims, const int64_t *shape, const int64_t *strides, const int64_t offset );
```

</section>

<!-- /.usage -->

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<section class="notes">

</section>

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<!-- C API usage examples. -->

<section class="examples">

### Examples

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

int main( void ) {
    // Specify the number of dimensions:
    const int64_t ndims = 2;

    // Define an array shape:
    const int64_t shape[] = { 10, 10 };

    // Define array strides:
    const int64_t strides[] = { -2, 5 };

    // Define an offset:
    const int64_t offset = 100;

    // Compute the maximum accessible index:
    int64_t idx = stdlib_ndarray_max_view_buffer_index( ndims, shape, strides, offset );

    // Print the results:
    printf( "idx: %"PRId64"\n", idx );
}
```

</section>

<!-- /.examples -->

</section>

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## Notice

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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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