Skip to content

Commit

Permalink
feat: add BLAS Level 2 routine for dtpmv
Browse files Browse the repository at this point in the history
  • Loading branch information
aman-095 committed Aug 24, 2024
1 parent 50b38f9 commit 89b6e5e
Show file tree
Hide file tree
Showing 46 changed files with 3,754 additions and 0 deletions.
256 changes: 256 additions & 0 deletions lib/node_modules/@stdlib/blas/base/dtpmv/README.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,256 @@
<!--
@license Apache-2.0
Copyright (c) 2024 The Stdlib Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->

# dtpmv

> Perform one of the matrix-vector operations `x = A*x` or `x = A^T*x`.
<section class = "usage">

## Usage

```javascript
var dtpmv = require( '@stdlib/blas/base/dtpmv' );
```

#### dtpmv( order, uplo, trans, diag, N, AP, x, sx )

Performs one of the matrix-vector operations `x = A*x` or `x = A^T*x`, where `x` is an `N` element vector and `A` is an `N` by `N` unit, or non-unit, upper or lower triangular matrix, supplied in packed form.

```javascript
var Float64Array = require( '@stdlib/array/float64' );

var AP = new Float64Array( [ 1.0, 2.0, 3.0, 1.0, 2.0, 1.0 ] );
var x = new Float64Array( [ 1.0, 2.0, 3.0 ] );

dtpmv( 'row-major', 'upper', 'no-transpose', 'unit', 3, AP, x, 1 );
// x => <Float64Array>[ 14.0, 8.0, 3.0 ]
```

The function has the following parameters:

- **order**: storage layout.
- **uplo**: specifies whether `A` is an upper or lower triangular matrix.
- **trans**: specifies whether `A` should be transposed, conjugate-transposed, or not transposed.
- **diag**: specifies whether `A` has a unit diagonal.
- **N**: number of elements along each dimension of `A`.
- **AP**: packed form of matrix `A` stored in linear memory as a [`Float64Array`][mdn-float64array].
- **x**: input vector [`Float64Array`][mdn-float64array].
- **sx**: `x` stride length.

The stride parameters determine how elements in the input arrays are accessed at runtime. For example, to iterate over the elements of `x` in reverse order,

```javascript
var Float64Array = require( '@stdlib/array/float64' );

var AP = new Float64Array( [ 1.0, 2.0, 3.0, 1.0, 2.0, 1.0 ] );
var x = new Float64Array( [ 1.0, 2.0, 3.0 ] );

dtpmv( 'row-major', 'upper', 'no-transpose', 'unit', 3, AP, x, -1 );
// x => <Float64Array>[ 1.0, 4.0, 10.0 ]
```

Note that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.

<!-- eslint-disable stdlib/capitalized-comments -->

```javascript
var Float64Array = require( '@stdlib/array/float64' );

// Initial arrays...
var x0 = new Float64Array( [ 1.0, 1.0, 1.0, 1.0 ] );
var AP = new Float64Array( [ 1.0, 2.0, 3.0, 1.0, 2.0, 1.0 ] );

// Create offset views...
var x1 = new Float64Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element

dtpmv( 'row-major', 'upper', 'no-transpose', 'unit', 3, AP, x1, 1 );
// x0 => <Float64Array>[ 1.0, 6.0, 3.0, 1.0 ]
```

#### dtpmv.ndarray( order, uplo, trans, diag, N, AP, sap, oap, x, sx, ox )

Performs one of the matrix-vector operations `x = A*x` or `x = A^T*x`, using alternative indexing semantics and where `x` is an `N` element vector and `A` is an `N` by `N` unit, or non-unit, upper or lower triangular matrix, supplied in packed form.

```javascript
var Float64Array = require( '@stdlib/array/float64' );

var AP = new Float64Array( [ 1.0, 2.0, 3.0, 1.0, 2.0, 1.0 ] );
var x = new Float64Array( [ 1.0, 2.0, 3.0 ] );

dtpmv.ndarray( 'row-major', 'upper', 'no-transpose', 'unit', 3, AP, 1, 0, x, 1, 0 );
// x => <Float64Array>[ 14.0, 8.0, 3.0 ]
```

The function has the following additional parameters:

- **sap**: `AP` stride length
- **oap**: starting index for `AP`.
- **ox**: starting index for `x`.

While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying buffer, the offset parameters support indexing semantics based on starting indices. For example,

```javascript
var Float64Array = require( '@stdlib/array/float64' );

var AP = new Float64Array( [ 1.0, 2.0, 3.0, 1.0, 2.0, 1.0 ] );
var x = new Float64Array( [ 1.0, 2.0, 3.0 ] );

dtpmv.ndarray( 'row-major', 'upper', 'no-transpose', 'unit', 3, AP, 1, 0, x, -1, 2 );
// x => <Float64Array>[ 1.0, 4.0, 10.0 ]
```

</section>

<!-- /.usage -->

<section class="notes">

## Notes

- `dtpmv()` corresponds to the [BLAS][blas] level 2 function [`dtpmv`][blas-dtpmv].

</section>

<!-- /.notes -->

<section class="examples">

## Examples

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

```javascript
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var dtpmv = require( '@stdlib/blas/base/dtpmv' );

var opts = {
'dtype': 'float64'
};

var N = 5;

var AP = discreteUniform( N*(N+1)/2, -10.0, 10.0, opts );
var x = discreteUniform( N, -10.0, 10.0, opts );

dtpmv( 'column-major', 'upper', 'no-transpose', 'non-unit', N, AP, x, 1 );
console.log( x );

dtpmv.ndarray( 'column-major', 'upper', 'no-transpose', 'non-unit', N, AP, 1, 0, x, 1, 0 );
console.log( x );
```

</section>

<!-- /.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
TODO
```

#### TODO

TODO.

```c
TODO
```

TODO

```c
TODO
```

</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
TODO
```

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

[blas]: http://www.netlib.org/blas

[blas-dtpmv]: https://www.netlib.org/lapack/explore-html/db/d62/group__tpmv_gaf61fb853f06adfe9c44a0b71a5d505f7.html#gaf61fb853f06adfe9c44a0b71a5d505f7

[mdn-float64array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float64Array

[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray

</section>

<!-- /.links -->
104 changes: 104 additions & 0 deletions lib/node_modules/@stdlib/blas/base/dtpmv/benchmark/benchmark.js
Original file line number Diff line number Diff line change
@@ -0,0 +1,104 @@
/**
* @license Apache-2.0
*
* Copyright (c) 2024 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

// MODULES //

var bench = require( '@stdlib/bench' );
var isnan = require( '@stdlib/math/base/assert/is-nan' );
var ones = require( '@stdlib/array/ones' );
var pow = require( '@stdlib/math/base/special/pow' );
var floor = require( '@stdlib/math/base/special/floor' );
var pkg = require( './../package.json' ).name;
var dtpmv = require( './../lib/dtpmv.js' );


// VARIABLES //

var options = {
'dtype': 'float64'
};


// FUNCTIONS //

/**
* Creates a benchmark function.
*
* @private
* @param {PositiveInteger} N - number of elements along each dimension
* @returns {Function} benchmark function
*/
function createBenchmark( N ) {
var AP = ones( N*(N+1)/2, options.dtype );
var x = ones( N, options.dtype );
return benchmark;

/**
* Benchmark function.
*
* @private
* @param {Benchmark} b - benchmark instance
*/
function benchmark( b ) {
var z;
var i;

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
z = dtpmv( 'row-major', 'upper', 'transpose', 'non-unit', N, AP, x, 1 );
if ( isnan( z[ i%z.length ] ) ) {
b.fail( 'should not return NaN' );
}
}
b.toc();
if ( isnan( z[ i%z.length ] ) ) {
b.fail( 'should not return NaN' );
}
b.pass( 'benchmark finished' );
b.end();
}
}


// MAIN //

/**
* Main execution sequence.
*
* @private
*/
function main() {
var min;
var max;
var N;
var f;
var i;

min = 1; // 10^min
max = 6; // 10^max

for ( i = min; i <= max; i++ ) {
N = floor( pow( pow( 10, i ), 1.0/2.0 ) );
f = createBenchmark( N );
bench( pkg+':size='+(N*N), f );
}
}

main();
Loading

0 comments on commit 89b6e5e

Please sign in to comment.