feat: add blas/base/cdotc

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

@@ -0,0 +1,335 @@
+<!--
+
+@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.
+
+-->
+
+# cdotc
+
+> Calculate the dot product `x^H * y` of `x` and `y`.
+
+<section class="intro">
+
+The [dot product][dot-product] (or scalar product) is defined as
+
+</section>
+
+<!-- /.intro -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var cdotc = require( '@stdlib/blas/base/cdotc' );
+```
+
+#### cdotc( N, x, strideX, y, strideY )
+
+Calculates the dot product `x^H * y` of `x` and `y`.
+
+```javascript
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+
+var x = new Complex64Array( [ 7.0, -8.0, -1.0, -9.0 ] );
+var y = new Complex64Array( [ 6.0, -6.0, -9.0, 5.0 ] );
+
+var out = cdotc( x.length, x, 1, y, 1 );
+// returns <Complex64>[ 54.0, -80.0 ]
+```
+
+The function has the following parameters:
+
+-   **N**: number of indexed elements.
+-   **x**: input [`Complex64Array`][@stdlib/array/complex64].
+-   **strideX**: index increment for `x`.
+-   **y**: input [`Complex64Array`][@stdlib/array/complex64].
+-   **strideY**: index increment for `y`.
+
+The `N` and stride parameters determine which elements in the strided arrays are accessed at runtime. For example, to calculate the dot product of every other value in `x` and the first `N` elements of `y` in reverse order,
+
+```javascript
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+
+var x = new Complex64Array( [ -1.0, -9.0, 2.0, -8.0 ] );
+var y = new Complex64Array( [ -5.0, 1.0, -6.0, 7.0 ] );
+
+var out = cdotc( x.length, x, 1, y, -1 );
+// returns <Complex64>[ -75.0, -99.0 ]
+```
+
+#### cdotc.ndarray( N, x, strideX, offsetX, y, strideY, offsetY )
+
+Calculates the dot product `x^H * y` of `x` and `y` using alternative indexing semantics.
+
+```javascript
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+
+var x = new Complex64Array( [ 7.0, -8.0, -1.0, -9.0 ] );
+var y = new Complex64Array( [ 6.0, -6.0, -9.0, 5.0 ] );
+
+var out = cdotc.ndarray( x.length, x, 1, 0, y, 1, 0 );
+// returns <Complex64>[ 54.0, -80.0 ]
+```
+
+The function has the following additional parameters:
+
+-   **offsetX**: starting index for `x`.
+-   **offsetY**: 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, to calculate the dot product of every other value in `x` starting from the second value with the last 2 elements in `y` in reverse order
+
+```javascript
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+
+var x = new Complex64Array( [ 7.0, -8.0, -1.0, -9.0 ] );
+var y = new Complex64Array( [ 6.0, -6.0, -9.0, 5.0 ] );
+
+var out = cdotc.ndarray( x.length, x, 1, 0, y, -1, y.length-1 );
+// returns <Complex64>[ -55.0, 23.0 ]
+```
+
+</section>
+
+<!-- /.usage -->
+
+<section class="notes">
+
+## Notes
+
+-   If `N <= 0`, both functions return complex64 with real and imaginary as `0.0`.
+-   `cdotc()` corresponds to the [BLAS][blas] level 1 function [`cdotc`][cdotc].
+
+</section>
+
+<!-- /.notes -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
+var filledarrayBy = require( '@stdlib/array/filled-by' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+var cdotc = require( '@stdlib/blas/base/cdotc' );
+
+function rand() {
+    return new Complex64( discreteUniform( 0, 10 ), discreteUniform( 1, 5 ) );
+}
+
+var x = filledarrayBy( 10, 'complex64', rand );
+console.log( x.toString() );
+
+var y = filledarrayBy( 10, 'complex64', rand );
+console.log( y.toString() );
+
+// Perform dot product of x and y
+var out = cdotc.ndarray( x.length, x, 1, 0, y, -1, y.length-1 );
+console.log( out );
+```
+
+</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
+#include "stdlib/blas/base/cdotc.h"
+```
+
+#### c_cdotc( N, \*X, strideX, \*Y, strideY )
+
+Calculates the dot product `x^H * y` of `x` and `y`.
+
+```c
+#include "stdlib/complex/float32/ctor.h"
+
+float x[] = { 7.0f, -8.0f, -1.0f, -9.0f };
+float y[] = { 6.0f, -6.0f, -9.0f, 5.0f };
+
+stdlib_complex64_t out = c_cdotc( 2, (void *)x, 1, (void *)y, 1 );
+```
+
+The function accepts the following arguments:
+
+-   **N**: `[in] CBLAS_INT` number of indexed elements.
+-   **X**: `[in] void*` first input array.
+-   **strideX**: `[in] CBLAS_INT` index increment for `X`.
+-   **Y**: `[in] void*` second input array.
+-   **strideY**: `[in] CBLAS_INT` index increment for `Y`.
+
+```c
+stdlib_complex64_t c_cdotc( const CBLAS_INT N, const void *X, const CBLAS_INT strideX, const void *Y, const CBLAS_INT strideY );
+```
+
+#### c_cdotc_ndarray( N, \*X, strideX, offsetX, \*Y, strideY, offsetY )
+
+Calculates the dot product `x^H * y` of `x` and `y` using alternative indexing semantics.
+
+```c
+#include "stdlib/complex/float32/ctor.h"
+
+float x[] = { 7.0f, -8.0f, -1.0f, -9.0f };
+float y[] = { 6.0f, -6.0f, -9.0f, 5.0f };
+
+stdlib_complex64_t out = c_cdotc_ndarray( 2, (void *)x, 1, 0, (void *)y, 1, 0 );
+```
+
+The function accepts the following arguments:
+
+-   **N**: `[in] CBLAS_INT` number of indexed elements.
+-   **X**: `[in] void*` first input array.
+-   **strideX**: `[in] CBLAS_INT` index increment for `X`.
+-   **offsetX**: `[in] CBLAS_INT` starting index for `X`.
+-   **Y**: `[in] void*` second input array.
+-   **strideY**: `[in] CBLAS_INT` index increment for `Y`.
+-   **offsetY**: `[in] CBLAS_INT` starting index for `Y`.
+
+```c
+stdlib_complex64_t c_cdotc_ndarray( const CBLAS_INT N, const void *X, const CBLAS_INT strideX, const CBLAS_INT offsetX, const void *Y, const CBLAS_INT strideY, const CBLAS_INT offsetY );
+```
+
+</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/base/cdotc.h"
+#include "stdlib/complex/float32/ctor.h"
+#include "stdlib/complex/float32/reim.h"
+#include <stdio.h>
+
+int main( void ) {
+    // Create strided arrays of interleaved real and imaginary components:
+    float x[] = { 7.0f, -8.0f, -1.0f, -9.0f };
+    float y[] = { 6.0f, -6.0f, -9.0f, 5.0f };
+
+    // Specify the number of elements:
+    const int N = 2;
+
+    // Specify stride lengths:
+    const int strideX = 1;
+    const int strideY = 1;
+
+    // Compute the dot product:
+    stdlib_complex64_t dot = c_cdotc( N, (void *)x, strideX, (void *)y, strideY );
+
+    // Print the result:
+    float re;
+    float im;
+    stdlib_complex64_reim( dot, &re, &im );
+    printf( "cdotc( x, y ) = %f + %fi\n", re, im );
+
+    // Compute the dot product using alternative indexing semantics:
+    dot = c_cdotc_ndarray( N, (void *)x, -strideX, 1, (void *)y, strideY, 0 );
+
+    // Print the result:
+    stdlib_complex64_reim( dot, &re, &im );
+    printf( "cdotc( x, y ) = %f + %fi\n", re, im );
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+</section>
+
+<!-- /.c -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+* * *
+
+## See Also
+
+-   <span class="package-name">[`@stdlib/blas/base/cdotu`][@stdlib/blas/base/cdotu]</span><span class="delimiter">: </span><span class="description">calculate the dot product of two single-precision complex floating-point vectors.</span>
+-   <span class="package-name">[`@stdlib/blas/base/zdotc`][@stdlib/blas/base/zdotc]</span><span class="delimiter">: </span><span class="description">calculate the dot product of two double-precision complex floating-point vectors, conjugating the first vector.</span>
+
+</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">
+
+[dot-product]: https://en.wikipedia.org/wiki/Dot_product
+
+[blas]: http://www.netlib.org/blas
+
+[cdotc]: http://www.netlib.org/lapack/explore-html/df/d28/group__single__blas__level1.html
+
+[@stdlib/array/complex64]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/array/complex64
+
+[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
+
+<!-- <related-links> -->
+
+[@stdlib/blas/base/cdotu]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/blas/base/cdotu
+
+[@stdlib/blas/base/zdotc]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/blas/base/zdotc
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->