feat: add c implementation for blas/base/dgemm

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Author: dhruvan2006

lib/node_modules/@stdlib/blas/base/dgemm/README.md

@@ -190,18 +190,79 @@ console.log( C );
 #include "stdlib/blas/base/dgemm.h"
 ```
 
-#### TODO
+#### c_dgemm( layout, transA, transB, M, N, K, alpha, \*A, LDA, \*B, LDB, beta, \*C, LDC )
 
-TODO.
+Performs the matrix-matrix operation `C = α*op(A)*op(B) + β*C` where `op(X)` is either `op(X) = X` or `op(X) = X^T`, `α` and `β` are scalars, `A`, `B`, and `C` are matrices, with `op(A)` an `M` by `K` matrix, `op(B)` a `K` by `N` matrix, and `C` an `M` by `N` matrix.
+
+```c
+#include "stdlib/blas/base/shared.h"
+
+const double A[] = { 1.0, 2.0, 3.0, 4.0 };
+const double B[] = { 1.0, 1.0, 0.0, 1.0 };
+double C[] = { 1.0, 2.0, 3.0, 4.0 };
+
+c_dgemm( CblasRowMajor, CblasNoTrans, CblasNoTrans, 2, 2, 2, 1.0, A, 2, B, 2, 1.0, C, 2 );
+```
+
+The function accepts the following arguments:
+
+-   **layout**: `[in] CBLAS_LAYOUT` storage layout.
+-   **transA**: `[in] CBLAS_TRANSPOSE` specifies whether `A` should be transposed, conjugate-transposed, or not transposed.
+-   **transB**: `[in] CBLAS_TRANSPOSE` specifies whether `B` should be transposed, conjugate-transposed, or not transposed.
+-   **M**: `[in] CBLAS_INT` number of rows in the matrix `op(A)` and in the matrix `C`.
+-   **N**: `[in] CBLAS_INT` number of columns in the matrix `op(B)` and in the matrix `C`.
+-   **K**: `[in] CBLAS_INT` number of columns in the matrix `op(A)` and number of rows in the matrix `op(B)`.
+-   **alpha**: `[in] double` scalar constant.
+-   **A**: `[in] double*` first input matrix.
+-   **LDA**: `[in] CBLAS_INT` stride of the first dimension of `A` (a.k.a., leading dimension of the matrix `A`).
+-   **B**: `[in] double*` second input matrix.
+-   **LDB**: `[in] CBLAS_INT` stride of the first dimension of `B` (a.k.a., leading dimension of the matrix `B`).
+-   **beta**: `[in] double` scalar constant.
+-   **C**: `[inout] double*` third input matrix.
+-   **LDC**: `[in] CBLAS_INT` stride of the first dimension of `C` (a.k.a., leading dimension of the matrix `C`).
+
+```c
+void c_dgemm( const CBLAS_LAYOUT layout, const CBLAS_TRANSPOSE transA, const CBLAS_TRANSPOSE transB, const CBLAS_INT M, const CBLAS_INT N, const CBLAS_INT K, const double alpha, const double *A, const CBLAS_INT LDA, const double *B, const CBLAS_INT LDB, const double beta, double *C, const CBLAS_INT LDC )
+```
+
+#### c_dgemm_ndarray( transA, transB, M, N, K, alpha, \*A, sa1, sa2, oa, \*B, sb1, sb2, ob, beta, \*C, sc1, sc2, oc )
+
+Performs the matrix-matrix operation `C = α*op(A)*op(B) + β*C`, using alternative indexing semantics and where `op(X)` is either `op(X) = X` or `op(X) = X^T`, `α` and `β` are scalars, `A`, `B`, and `C` are matrices, with `op(A)` an `M` by `K` matrix, `op(B)` a `K` by `N` matrix, and `C` an `M` by `N` matrix.
 
 ```c
-TODO
+#include "stdlib/blas/base/shared.h"
+
+const double A[] = { 1.0, 2.0, 3.0, 4.0 };
+const double B[] = { 1.0, 1.0, 0.0, 1.0 };
+double C[] = { 1.0, 2.0, 3.0, 4.0 };
+
+c_dgemm_ndarray( CblasNoTrans, CblasNoTrans, 2, 2, 2, 1.0, A, 2, 1, 0, B, 2, 1, 0, 1.0, C, 2, 1, 0 );
 ```
 
-TODO
+The function accepts the following arguments:
+
+-   **transA**: `[in] CBLAS_TRANSPOSE` specifies whether `A` should be transposed, conjugate-transposed, or not transposed.
+-   **transB**: `[in] CBLAS_TRANSPOSE` specifies whether `B` should be transposed, conjugate-transposed, or not transposed.
+-   **M**: `[in] CBLAS_INT` number of rows in the matrix `op(A)` and in the matrix `C`.
+-   **N**: `[in] CBLAS_INT` number of columns in the matrix `op(B)` and in the matrix `C`.
+-   **K**: `[in] CBLAS_INT` number of columns in the matrix `op(A)` and number of rows in the matrix `op(B)`.
+-   **alpha**: `[in] double` scalar constant.
+-   **A**: `[in] double*` first input matrix.
+-   **sa1**: `[in] CBLAS_INT` stride of the first dimension of `A`.
+-   **sa2**: `[in] CBLAS_INT` stride of the second dimension of `A`.
+-   **oa**: `[in] CBLAS_INT` starting index for `A`.
+-   **B**: `[in] double*` second input matrix.
+-   **sb1**: `[in] CBLAS_INT` stride of the first dimension of `B`.
+-   **sb2**: `[in] CBLAS_INT` stride of the second dimension of `B`.
+-   **ob**: `[in] CBLAS_INT` starting index for `B`.
+-   **beta**: `[in] double` scalar constant.
+-   **C**: `[inout] double*` third input matrix.
+-   **sc1**: `[in] CBLAS_INT` stride of the first dimension of `C`.
+-   **sc2**: `[in] CBLAS_INT` stride of the second dimension of `C`.
+-   **oc**: `[in] CBLAS_INT` starting index for `C`.
 
 ```c
-TODO
+void c_dgemm_ndarray( const CBLAS_TRANSPOSE transA, const CBLAS_TRANSPOSE transB, const CBLAS_INT M, const CBLAS_INT N, const CBLAS_INT K, const double alpha, const double *A, const CBLAS_INT strideA1, const CBLAS_INT strideA2, const CBLAS_INT offsetA, const double *B, const CBLAS_INT strideB1, const CBLAS_INT strideB2, const CBLAS_INT offsetB, const double beta, double *C, const CBLAS_INT strideC1, const CBLAS_INT strideC2, const CBLAS_INT offsetC )
 ```
 
 </section>
@@ -223,7 +284,52 @@ TODO
 ### Examples
 
 ```c
-TODO
+#include "stdlib/blas/base/dgemm.h"
+#include "stdlib/blas/base/shared.h"
+#include <stdio.h>
+
+int main( void ) {
+    // Define matrices stored in row-major order:
+    const double A[ 3*2 ] = {
+        1.0, 2.0,
+        3.0, 4.0,
+        5.0, 6.0
+    };
+    const double B[ 2*4 ] = {
+        1.0, 2.0, 3.0, 4.0,
+        5.0, 6.0, 7.0, 8.0
+    };
+    double C[ 3*4 ] = {
+        1.0, 2.0, 3.0, 4.0,
+        5.0, 6.0, 7.0, 8.0,
+        9.0, 10.0, 11.0, 12.0
+    };
+
+    // Specify matrix dimensions:
+    const int M = 3;
+    const int N = 4;
+    const int K = 2;
+
+    // Perform the matrix-matrix operation `C = α*A*B + β*C`:
+    c_dgemm( CblasRowMajor, CblasNoTrans, CblasNoTrans, M, N, K, 1.0, A, K, B, N, 1.0, C, N );
+
+    // Print the result:
+    for ( int i = 0; i < M; i++ ) {
+        for ( int j = 0; j < N; j++ ) {
+            printf( "C[ %i ][ %i ] = %lf\n", i, j, C[ (i*N)+j ] );
+        }
+    }
+
+    // Perform the matrix-matrix operation `C = α*A*B + β*C` using alternative indexing semantics:
+    c_dgemm_ndarray( CblasNoTrans, CblasNoTrans, M, N, K, 1.0, A, K, 1, 0, B, N, 1, 0, 1.0, C, N, 1, 0 );
+
+    // Print the result:
+    for ( int i = 0; i < M; i++ ) {
+        for ( int j = 0; j < N; j++ ) {
+            printf( "C[ %i ][ %i ] = %lf\n", i, j, C[ (i*N)+j ] );
+        }
+    }
+}
 ```
 
 </section>

lib/node_modules/@stdlib/blas/base/dgemm/benchmark/benchmark.native.js

@@ -0,0 +1,111 @@
+/**
+* @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 resolve = require( 'path' ).resolve;
+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 tryRequire = require( '@stdlib/utils/try-require' );
+var pkg = require( './../package.json' ).name;
+
+
+// VARIABLES //
+
+var dgemm = tryRequire( resolve( __dirname, './../lib/dgemm.native.js' ) );
+var opts = {
+	'skip': ( dgemm instanceof Error )
+};
+var options = {
+	'dtype': 'float64'
+};
+
+
+// FUNCTIONS //
+
+/**
+* Creates a benchmark function.
+*
+* @private
+* @param {PositiveInteger} N - array dimension size
+* @returns {Function} benchmark function
+*/
+function createBenchmark( N ) {
+	var A = uniform( N*N, -10.0, 10.0, options );
+	var B = uniform( N*N, -10.0, 10.0, options );
+	var C = uniform( N*N, -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 = dgemm( 'row-major', 'no-transpose', 'no-transpose', N, N, N, 1.0, A, N, B, N, 1.0, C, N );
+			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 = 5; // 10^max
+
+	for ( i = min; i <= max; i++ ) {
+		N = floor( pow( pow( 10, i ), 1.0/2.0 ) );
+		f = createBenchmark( N );
+		bench( format( '%s::native:size=%d', pkg, N*N ), opts, f );
+	}
+}
+
+main();

lib/node_modules/@stdlib/blas/base/dgemm/benchmark/benchmark.ndarray.native.js

@@ -0,0 +1,111 @@
+/**
+* @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 resolve = require( 'path' ).resolve;
+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 tryRequire = require( '@stdlib/utils/try-require' );
+var pkg = require( './../package.json' ).name;
+
+
+// VARIABLES //
+
+var dgemm = tryRequire( resolve( __dirname, './../lib/ndarray.native.js' ) );
+var opts = {
+	'skip': ( dgemm instanceof Error )
+};
+var options = {
+	'dtype': 'float64'
+};
+
+
+// FUNCTIONS //
+
+/**
+* Creates a benchmark function.
+*
+* @private
+* @param {PositiveInteger} N - array dimension size
+* @returns {Function} benchmark function
+*/
+function createBenchmark( N ) {
+	var A = uniform( N*N, -10.0, 10.0, options );
+	var B = uniform( N*N, -10.0, 10.0, options );
+	var C = uniform( N*N, -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 = dgemm( 'no-transpose', 'no-transpose', N, N, N, 1.0, A, 1, N, 0, B, 1, N, 0, 1.0, C, 1, N, 0 );
+			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 = 5; // 10^max
+
+	for ( i = min; i <= max; i++ ) {
+		N = floor( pow( pow( 10, i ), 1.0/2.0 ) );
+		f = createBenchmark( N );
+		bench( format( '%s::native:ndarray:size=%d', pkg, N*N ), opts, f );
+	}
+}
+
+main();