feat: add blas/ext/base/cfill

lib/node_modules/@stdlib/blas/ext/base/cfill/README.md

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+<!--
+
+@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.
+
+-->
+
+# cfill
+
+> Fill a single-precision complex floating-point strided array with a specified complex floating-point constant.
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var cfill = require( '@stdlib/blas/ext/base/cfill' );
+```
+
+#### cfill( N, alpha, x, stride )
+
+Fills a single-precision complex floating-point strided array `x` with a specified complex floating-point constant `alpha`.
+
+```javascript
+var Float32Array = require( '@stdlib/array/float32' );
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+var realf = require( '@stdlib/complex/float32/real' );
+var imagf = require( '@stdlib/complex/float32/imag' );
+
+var arr = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );
+var x = new Complex64Array( arr );
+var alpha = new Complex64( 10.0, 10.0 );
+
+cfill( x.length, alpha, x, 1 );
+
+var y = x.get( 0 );
+// returns <Complex64>
+
+var re = realf( y );
+// returns 10.0
+
+var im = imagf( y );
+// returns 10.0
+```
+
+The function has the following parameters:
+
+-   **N**: number of indexed elements.
+-   **alpha**: complex constant.
+-   **x**: input [`Complex64Array`][@stdlib/array/complex64].
+-   **stride**: index increment.
+
+The `N` and stride parameters determine which elements in the strided array are accessed at runtime. For example, to fill every other element
+
+```javascript
+var Float32Array = require( '@stdlib/array/float32' );
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+var realf = require( '@stdlib/complex/float32/real' );
+var imagf = require( '@stdlib/complex/float32/imag' );
+
+var arr = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );
+var x = new Complex64Array( arr );
+var alpha = new Complex64( 10.0, 10.0 );
+
+cfill( 2, alpha, x, 2 );
+
+var y = x.get( 0 );
+// returns <Complex64>
+
+var re = realf( y );
+// returns 10.0
+
+var im = imagf( y );
+// returns 10.0
+
+y = x.get( 1 );
+// returns <Complex64>
+
+re = realf( y );
+// returns 3.0
+
+im = imagf( y );
+// returns 4.0
+```
+
+Note that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.
+
+```javascript
+var Float32Array = require( '@stdlib/array/float32' );
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+var realf = require( '@stdlib/complex/float32/real' );
+var imagf = require( '@stdlib/complex/float32/imag' );
+
+// Create the underlying floating-point array
+var arr = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );
+
+// Initial array...
+var x0 = new Complex64Array( arr );
+
+// Create an offset view...
+var x1 = new Complex64Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
+
+// Define the complex constant
+var alpha = new Complex64( 10.0, 10.0 );
+
+// Fill every other element...
+cfill( 2, alpha, x1, 2 );
+
+var y = x0.get( 0 );
+// returns <Complex64>
+
+var re = realf( y );
+// returns 1.0
+
+var im = imagf( y );
+// returns 2.0
+
+y = x0.get( 1 );
+// returns <Complex64>
+
+re = realf( y );
+// returns 10.0
+
+im = imagf( y );
+// returns 10.0
+```
+
+#### cfill.ndarray( N, alpha, x, stride, offset )
+
+Fills a single-precision complex floating-point strided array `x` with a specified complex floating-point constant `alpha` using alternative indexing semantics.
+
+```javascript
+var Float32Array = require( '@stdlib/array/float32' );
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+var realf = require( '@stdlib/complex/float32/real' );
+var imagf = require( '@stdlib/complex/float32/imag' );
+
+var arr = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 ] );
+var x = new Complex64Array( arr );
+var alpha = new Complex64( 10.0, 10.0 );
+
+cfill.ndarray( x.length, alpha, x, 1, 0 );
+
+var y = x.get( 0 );
+// returns <Complex64>
+
+var re = realf( y );
+// returns 10.0
+
+var im = imagf( y );
+// returns 10.0
+```
+
+The function has the following additional parameters:
+
+-   **offset**: 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 access only the last two elements of the strided array
+
+```javascript
+var Float32Array = require( '@stdlib/array/float32' );
+var Complex64Array = require( '@stdlib/array/complex64' );
+var Complex64 = require( '@stdlib/complex/float32/ctor' );
+var realf = require( '@stdlib/complex/float32/real' );
+var imagf = require( '@stdlib/complex/float32/imag' );
+
+var arr = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
+var x = new Complex64Array( arr );
+var alpha = new Complex64( 10.0, 10.0 );
+
+cfill.ndarray( 2, alpha, x, 1, x.length-2 );
+
+var y = x.get( 0 );
+// returns <Complex64>
+
+var re = realf( y );
+// returns 1.0
+
+var im = imagf( y );
+// returns 2.0
+
+y = x.get( 1 );
+// returns <Complex64>
+
+re = realf( y );
+// returns 10.0
+
+im = imagf( y );
+// returns 10.0
+
+y = x.get( 2 );
+// returns <Complex64>
+
+re = realf( y );
+// returns 10.0
+
+im = imagf( y );
+// returns 10.0
+```
+
+</section>
+
+<!-- /.usage -->
+
+<section class="notes">
+
+## Notes
+
+-   If `N <= 0`, both functions return the strided array unchanged.
+
+</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 cfill = require( '@stdlib/blas/ext/base/cfill' );
+
+function rand() {
+    return new Complex64( discreteUniform( 0, 10 ), discreteUniform( -5, 5 ) );
+}
+
+var x = filledarrayBy( 10, 'complex64', rand );
+
+var alpha = new Complex64( 10.0, 10.0 );
+
+cfill( x.length, alpha, x, 1 );
+console.log( x.get( 0 ).toString() );
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- 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/ext/base/dfill`][@stdlib/blas/ext/base/dfill]</span><span class="delimiter">: </span><span class="description">fill a double-precision floating-point strided array with a specified scalar constant.</span>
+-   <span class="package-name">[`@stdlib/blas/ext/base/gfill`][@stdlib/blas/ext/base/gfill]</span><span class="delimiter">: </span><span class="description">fill a strided array with a specified scalar constant.</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">
+
+[@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/ext/base/dfill]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/blas/ext/base/dfill
+
+[@stdlib/blas/ext/base/gfill]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/blas/ext/base/gfill
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->