Skip to content

Commit

Permalink
feat: add C ndarray API and refactor blas/ext/base/snansumkbn2
Browse files Browse the repository at this point in the history
PR-URL: stdlib-js#4846
Reviewed-by: Athan Reines <[email protected]>
  • Loading branch information
headlessNode authored and Vinit-Pandit committed Feb 4, 2025
1 parent 47a4cdf commit fa90bfe
Show file tree
Hide file tree
Showing 22 changed files with 425 additions and 203 deletions.
133 changes: 124 additions & 9 deletions lib/node_modules/@stdlib/blas/ext/base/snansumkbn2/README.md
Original file line number Diff line number Diff line change
Expand Up @@ -36,7 +36,7 @@ limitations under the License.
var snansumkbn2 = require( '@stdlib/blas/ext/base/snansumkbn2' );
```

#### snansumkbn2( N, x, stride )
#### snansumkbn2( N, x, strideX )

Computes the sum of single-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm.

Expand All @@ -45,17 +45,17 @@ var Float32Array = require( '@stdlib/array/float32' );

var x = new Float32Array( [ 1.0, -2.0, NaN, 2.0 ] );

var v = snansumkbn2( 4, x, 1 );
var v = snansumkbn2( x.length, x, 1 );
// returns 1.0
```

The function has the following parameters:

- **N**: number of indexed elements.
- **x**: input [`Float32Array`][@stdlib/array/float32].
- **stride**: index increment for `x`.
- **strideX**: stride length.

The `N` and stride parameters determine which elements in the strided array are accessed at runtime. For example, to compute the sum of every other element in `x`,
The `N` and stride parameters determine which elements in the strided array are accessed at runtime. For example, to compute the sum of every other element:

```javascript
var Float32Array = require( '@stdlib/array/float32' );
Expand All @@ -80,7 +80,7 @@ var v = snansumkbn2( 4, x1, 2 );
// returns 5.0
```

#### snansumkbn2.ndarray( N, x, stride, offset )
#### snansumkbn2.ndarray( N, x, strideX, offsetX )

Computes the sum of single-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm and alternative indexing semantics.

Expand All @@ -89,15 +89,15 @@ var Float32Array = require( '@stdlib/array/float32' );

var x = new Float32Array( [ 1.0, -2.0, NaN, 2.0 ] );

var v = snansumkbn2.ndarray( 4, x, 1, 0 );
var v = snansumkbn2.ndarray( x.length, x, 1, 0 );
// returns 1.0
```

The function has the following additional parameters:

- **offset**: starting index for `x`.
- **offsetX**: starting index.

While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying `buffer`, the `offset` parameter supports indexing semantics based on a starting index. For example, to calculate the sum of every other value in `x` starting from the second value
While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying buffer, the offset parameter supports indexing semantics based on a starting index. For example, to calculate the sum of every other element starting from the second element:

```javascript
var Float32Array = require( '@stdlib/array/float32' );
Expand Down Expand Up @@ -135,7 +135,7 @@ var filledarrayBy = require( '@stdlib/array/filled-by' );
var snansumkbn2 = require( '@stdlib/blas/ext/base/snansumkbn2' );

function rand() {
if ( bernoulli( 0.8 ) > 0 ) {
if ( bernoulli( 0.5 ) < 1 ) {
return discreteUniform( 0, 100 );
}
return NaN;
Expand All @@ -152,8 +152,123 @@ console.log( v );

<!-- /.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/blas/ext/base/snansumkbn2.h"
```

#### stdlib_strided_snansumkbn2( N, \*X, strideX )

Computes the sum of single-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm.

```c
const float x[] = { 1.0f, 2.0f, 0.0f/0.0f, 4.0f };

float v = stdlib_strided_snansumkbn2( 4, x, 1 );
// returns 7.0f
```
The function accepts the following arguments:
- **N**: `[in] CBLAS_INT` number of indexed elements.
- **X**: `[in] float*` input array.
- **strideX**: `[in] CBLAS_INT` stride length.
```c
float stdlib_strided_snansumkbn2( const CBLAS_INT N, const float *X, const CBLAS_INT strideX );
```

#### stdlib_strided_snansumkbn2_ndarray( N, \*X, strideX, offsetX )

Computes the sum of single-precision floating-point strided array elements, ignoring `NaN` values and using a second-order iterative Kahan–Babuška algorithm and alternative indexing semantics.

```c
const float x[] = { 1.0f, 2.0f, 0.0f/0.0f, 4.0f };

float v = stdlib_strided_snansumkbn2_ndarray( 4, x, 1, 0 );
// returns 7.0f
```
The function accepts the following arguments:
- **N**: `[in] CBLAS_INT` number of indexed elements.
- **X**: `[in] float*` input array.
- **strideX**: `[in] CBLAS_INT` stride length.
- **offsetX**: `[in] CBLAS_INT` starting index.
```c
float stdlib_strided_snansumkbn2_ndarray( const CBLAS_INT N, const float *X, const CBLAS_INT strideX, const CBLAS_INT offsetX );
```

</section>

<!-- /.usage -->

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

<section class="notes">

</section>

<!-- /.notes -->

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

<section class="examples">

### Examples

```c
#include "stdlib/blas/ext/base/snansumkbn2.h"
#include <stdio.h>

int main( void ) {
// Create a strided array:
const float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f, 6.0f, 7.0f, 8.0f, 0.0f/0.0f, 0.0f/0.0f };

// Specify the number of elements:
const int N = 5;

// Specify the stride length:
const int strideX = 2;

// Compute the sum:
float v = stdlib_strided_snansumkbn2( N, x, strideX );

// Print the result:
printf( "Sum: %f\n", v );
}
```
</section>
<!-- /.examples -->
</section>
<!-- /.c -->
<section class="references">
## References
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,19 @@ var snansumkbn2 = require( './../lib/snansumkbn2.js' );

// FUNCTIONS //

/**
* Returns a random number.
*
* @private
* @returns {number} random number
*/
function rand() {
if ( bernoulli( 0.5 ) < 1 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

/**
* Creates a benchmark function.
*
Expand All @@ -43,13 +56,6 @@ function createBenchmark( len ) {
var x = filledarrayBy( len, 'float32', rand );
return benchmark;

function rand() {
if ( bernoulli( 0.8 ) > 0 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

function benchmark( b ) {
var v;
var i;
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -41,6 +41,19 @@ var opts = {

// FUNCTIONS //

/**
* Returns a random number.
*
* @private
* @returns {number} random number
*/
function rand() {
if ( bernoulli( 0.5 ) < 1 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

/**
* Creates a benchmark function.
*
Expand All @@ -52,13 +65,6 @@ function createBenchmark( len ) {
var x = filledarrayBy( len, 'float32', rand );
return benchmark;

function rand() {
if ( bernoulli( 0.8 ) > 0 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

function benchmark( b ) {
var v;
var i;
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,19 @@ var snansumkbn2 = require( './../lib/ndarray.js' );

// FUNCTIONS //

/**
* Returns a random number.
*
* @private
* @returns {number} random number
*/
function rand() {
if ( bernoulli( 0.5 ) < 1 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

/**
* Creates a benchmark function.
*
Expand All @@ -43,13 +56,6 @@ function createBenchmark( len ) {
var x = filledarrayBy( len, 'float32', rand );
return benchmark;

function rand() {
if ( bernoulli( 0.8 ) > 0 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

function benchmark( b ) {
var v;
var i;
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -41,6 +41,19 @@ var opts = {

// FUNCTIONS //

/**
* Returns a random number.
*
* @private
* @returns {number} random number
*/
function rand() {
if ( bernoulli( 0.5 ) < 1 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

/**
* Creates a benchmark function.
*
Expand All @@ -52,13 +65,6 @@ function createBenchmark( len ) {
var x = filledarrayBy( len, 'float32', rand );
return benchmark;

function rand() {
if ( bernoulli( 0.8 ) > 0 ) {
return uniform( -10.0, 10.0 );
}
return NaN;
}

function benchmark( b ) {
var v;
var i;
Expand Down
Loading

0 comments on commit fa90bfe

Please sign in to comment.