stdlib-js · MeKaustubh07 · Aug 17, 2026
diff --git a/lib/node_modules/@stdlib/blas/base/gspmv/README.md b/lib/node_modules/@stdlib/blas/base/gspmv/README.md
@@ -0,0 +1,189 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2026 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.
+
+-->
+
+# gspmv
+
+> Perform the matrix-vector operation `y = α*A*x + β*y` where `α` and `β` are scalars, `x` and `y` are `N` element vectors, and `A` is an `N` by `N` symmetric matrix supplied in packed form.
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var gspmv = require( '@stdlib/blas/base/gspmv' );
+```
+
+#### gspmv( order, uplo, N, α, AP, x, sx, β, y, sy )
+
+Performs the matrix-vector operation `y = α*A*x + β*y` where `α` and `β` are scalars, `x` and `y` are `N` element vectors, and `A` is an `N` by `N` symmetric matrix supplied in packed form `AP`.
+
+```javascript
+var AP = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
+var x = [ 1.0, 1.0, 1.0 ];
+var y = [ 1.0, 1.0, 1.0 ];
+
+gspmv( 'column-major', 'lower', 3, 1.0, AP, x, 1, 1.0, y, 1 );
+// y => [ 7.0, 12.0, 15.0 ]
+```
+
+The function has the following parameters:
+
+-   **order**: storage layout.
+-   **uplo**: specifies whether the upper or lower triangular part of the symmetric matrix `A` is supplied.
+-   **N**: number of elements along each dimension of `A`.
+-   **α**: scalar constant.
+-   **AP**: packed form of a symmetric matrix `A`.
+-   **x**: input vector.
+-   **sx**: index increment for `x`.
+-   **β**: scalar constant.
+-   **y**: output vector.
+-   **sy**: index increment for `y`.
+
+The stride parameters determine how elements in the input arrays are accessed at runtime. For example, to iterate over the elements of `y` in reverse order,
+
+```javascript
+var AP = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
+var x = [ 1.0, 1.0, 1.0 ];
+var y = [ 1.0, 1.0, 1.0 ];
+
+gspmv( 'column-major', 'lower', 3, 1.0, AP, x, 1, 1.0, y, -1 );
+// y => [ 15.0, 12.0, 7.0 ]
+```
+
+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( [ 0.0, 1.0, 1.0 ] );
+var y0 = new Float64Array( [ 0.0, 1.0, 1.0 ] );
+var AP = new Float64Array( [ 1.0, 2.0, 3.0 ] );
+
+// Create offset views...
+var x1 = new Float64Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
+var y1 = new Float64Array( y0.buffer, y0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
+
+gspmv( 'row-major', 'upper', 2, 1.0, AP, x1, -1, 1.0, y1, -1 );
+// y0 => <Float64Array>[ 0.0, 6.0, 4.0 ]
+```
+
+#### gspmv.ndarray( order, uplo, N, α, AP, oa, x, sx, ox, β, y, sy, oy )
+
+Performs the matrix-vector operation `y = α*A*x + β*y`, using alternative indexing semantics and where `α` and `β` are scalars, `x` and `y` are `N` element vectors, and `A` is an `N` by `N` symmetric matrix supplied in packed form `AP`.
+
+```javascript
+var AP = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
+var x = [ 1.0, 1.0, 1.0 ];
+var y = [ 1.0, 1.0, 1.0 ];
+
+gspmv.ndarray( 'column-major', 'lower', 3, 1.0, AP, 0, x, 1, 0, 1.0, y, 1, 0 );
+// y => [ 7.0, 12.0, 15.0 ]
+```
+
+The function has the following additional parameters:
+
+-   **oa**: starting index for `AP`.
+-   **ox**: starting index for `x`.
+-   **oy**: starting index for `y`.
+
+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 AP = [ 0.0, 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
+var x = [ 1.0, 1.0, 1.0 ];
+var y = [ 1.0, 1.0, 1.0 ];
+
+gspmv.ndarray( 'column-major', 'lower', 3, 1.0, AP, 2, x, 1, 0, 1.0, y, -1, 2 );
+// y => [ 15.0, 12.0, 7.0 ]
+```
+
+</section>
+
+<!-- /.usage -->
+
+<section class="notes">
+
+## Notes
+
+-   `gspmv()` corresponds to the [BLAS][blas] level 2 function [`dspmv`][dspmv] with the exception that this implementation works with any array type, not just Float64Arrays. Depending on the environment, typed versions such as [`dspmv`][@stdlib/blas/base/dspmv] and [`sspmv`][@stdlib/blas/base/sspmv] are likely to be significantly more performant.
+-   Both functions support array-like objects having getter and setter accessors for array element access (e.g., [`@stdlib/array/base/accessor`][@stdlib/array/base/accessor]).
+
+</section>
+
+<!-- /.notes -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var gspmv = require( '@stdlib/blas/base/gspmv' );
+
+var opts = {
+    'dtype': 'generic'
+};
+
+var N = 3;
+
+var AP = discreteUniform( N * ( N + 1 ) / 2, -10, 10, opts );
+var x = discreteUniform( N, -10, 10, opts );
+var y = discreteUniform( N, -10, 10, opts );
+
+gspmv.ndarray( 'row-major', 'upper', N, 1.0, AP, 0, x, 1, 0, 1.0, y, 1, 0 );
+console.log( y );
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- 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
+
+[dspmv]: https://www.netlib.org/lapack/explore-html/d0/d4b/group__hpmv_ga739f8dc2316523832bde2b237fcad8a6.html#ga739f8dc2316523832bde2b237fcad8a6
+
+[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
+
+[@stdlib/array/base/accessor]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/array/base/accessor
+
+[@stdlib/blas/base/dspmv]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/blas/base/dspmv
+
+[@stdlib/blas/base/sspmv]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/blas/base/sspmv
+
+</section>
+
+<!-- /.links -->
diff --git a/lib/node_modules/@stdlib/blas/base/gspmv/benchmark/benchmark.js b/lib/node_modules/@stdlib/blas/base/gspmv/benchmark/benchmark.js
@@ -0,0 +1,106 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 uniform = require( '@stdlib/random/array/uniform' );
+var format = require( '@stdlib/string/format' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var pow = require( '@stdlib/math/base/special/pow' );
+var floor = require( '@stdlib/math/base/special/floor' );
+var pkg = require( './../package.json' ).name;
+var gspmv = require( './../lib' );
+
+
+// VARIABLES //
+
+var options = {
+	'dtype': 'generic'
+};
+
+
+// FUNCTIONS //
+
+/**
+* Creates a benchmark function.
+*
+* @private
+* @param {PositiveInteger} len - array length
+* @returns {Function} benchmark function
+*/
+function createBenchmark( len ) {
+	var AP = uniform( len * ( len + 1 ) / 2, -10.0, 10.0, options );
+	var x = uniform( len, -10.0, 10.0, options );
+	var y = uniform( len, -10.0, 10.0, options );
+	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 = gspmv( 'row-major', 'upper', len, 1.0, AP, x, 1, 1.0, y, 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 len;
+	var min;
+	var max;
+	var f;
+	var i;
+
+	min = 1; // 10^min
+	max = 6; // 10^max
+
+	for ( i = min; i <= max; i++ ) {
+		len = floor( pow( pow( 10, i ), 1.0/2.0 ) );
+		f = createBenchmark( len );
+		bench( format( '%s:size=%d', pkg, len * ( len + 1 ) / 2 ), f );
+	}
+}
+
+main();