feat: add C ndarray API to blas/ext/base/cfill

PR-URL: #2925
Co-authored-by: Athan Reines <kgryte@gmail.com>
Reviewed-by: Athan Reines <kgryte@gmail.com> 
Signed-off-by: Athan Reines <kgryte@gmail.com>

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

@@ -30,7 +30,7 @@ limitations under the License.
 var cfill = require( '@stdlib/blas/ext/base/cfill' );
 ```
 
-#### cfill( N, alpha, x, stride )
+#### cfill( N, alpha, x, strideX )
 
 Fills a single-precision complex floating-point strided array `x` with a specified scalar constant `alpha`.
 
@@ -63,7 +63,7 @@ The function has the following parameters:
 -   **N**: number of indexed elements.
 -   **alpha**: scalar constant.
 -   **x**: input [`Complex64Array`][@stdlib/array/complex64].
--   **stride**: index increment.
+-   **strideX**: 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
 
@@ -143,7 +143,7 @@ im = imagf( y );
 // returns 10.0
 ```
 
-#### cfill.ndarray( N, alpha, x, stride, offset )
+#### cfill.ndarray( N, alpha, x, strideX, offsetX )
 
 Fills a single-precision complex floating-point strided array `x` with a specified scalar constant `alpha` using alternative indexing semantics.
 
@@ -173,9 +173,9 @@ var im = imagf( y );
 
 The function has the following additional parameters:
 
--   **offset**: starting index.
+-   **offsetX**: 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
+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' );
@@ -240,16 +240,15 @@ im = imagf( y );
 <!-- eslint no-undef: "error" -->
 
 ```javascript
-var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
-var filledarrayBy = require( '@stdlib/array/filled-by' );
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var Complex64Array = require( '@stdlib/array/complex64' );
 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 xbuf = discreteUniform( 20, -100, 100, {
+    'dtype': 'float32'
+});
+var x = new Complex64Array( xbuf.buffer );
 var alpha = new Complex64( 10.0, 10.0 );
 
 cfill( x.length, alpha, x, 1 );
@@ -260,6 +259,131 @@ console.log( x.get( 0 ).toString() );
 
 <!-- /.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/ext/base/cfill.h"
+```
+
+#### c_cfill( N, alpha, \*X, strideX )
+
+Fills a single-precision floating-point strided array `X` with a specified scalar constant `alpha`.
+
+```c
+float x[] = { 1.0f, 2.0f, 3.0f, 4.0f };
+const stdlib_complex64_t alpha = stdlib_complex64( 2.0f, 2.0f );
+
+c_cfill( 2, alpha, (stdlib_complex64_t *)x, 1 );
+```
+
+The function accepts the following arguments:
+
+-   **N**: `[in] CBLAS_INT` number of indexed elements.
+-   **alpha**: `[in] stdlib_complex64_t` scalar constant.
+-   **X**: `[out] stdlib_complex64_t*` input array.
+-   **strideX**: `[in] CBLAS_INT` index increment for `X`.
+
+```c
+void c_cfill( const CBLAS_INT N, const stdlib_complex64_t alpha, stdlib_complex64_t *X, const CBLAS_INT strideX );
+```
+
+#### c_cfill_ndarray( N, alpha, \*X, strideX, offsetX )
+
+Fills a single-precision complex floating-point strided array `X` with a specified scalar constant `alpha` using alternative indexing semantics.
+
+```c
+float x[] = { 1.0f, 2.0f, 3.0f, 4.0f };
+const stdlib_complex64_t alpha = stdlib_complex64( 2.0f, 2.0f );
+
+c_cfill_ndarray( 4, alpha, (stdlib_complex64_t *x), 1, 0 );
+```
+
+The function accepts the following arguments:
+
+-   **N**: `[in] CBLAS_INT` number of indexed elements.
+-   **alpha**: `[in] stlib_complex64_t` scalar constant.
+-   **X**: `[out] stdlib_complex64_t*` input array.
+-   **strideX**: `[in] CBLAS_INT` index increment for `X`.
+-   **offsetX**: `[in] CBLAS_INT` starting index for `X`.
+
+```c
+void c_cfill_ndarray( const CBLAS_INT N, const stdlib_complex64_t alpha, stdlib_complex_64_t *X, const CBLAS_INT strideX, const CBLAS_INT offsetX );
+```
+
+</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/ext/base/cfill.h"
+#include "stdlib/complex/float32/ctor.h"
+#include <stdio.h>
+
+int main( void ) {
+    // Create a strided array of interleaved real and imaginary components:
+    float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f, 6.0f, 7.0f, 8.0f };
+
+    // Create a complex scalar:
+    const stdlib_complex64_t alpha = stdlib_complex64( 2.0f, 2.0f );
+
+    // Specify the number of indexed elements:
+    const int N = 4;
+
+    // Specify a stride:
+    const int strideX = 1;
+
+    // Fill the array:
+    c_cfill( N, alpha, (stdlib_complex_64_t *)x, strideX );
+
+    // Print the result:
+    for ( int i = 0; i < N; i++ ) {
+        printf( "x[ %i ] = %f + %fj\n", i, x[ i*2 ], x[ (i*2)+1 ] );
+    }
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+</section>
+
+<!-- /.c -->
+
 <!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
 
 <section class="related">

lib/node_modules/@stdlib/blas/ext/base/cfill/benchmark/c/benchmark.length.c

@@ -95,7 +95,7 @@ static float rand_float( void ) {
 * @param len          array length
 * @return elapsed time in seconds
 */
-static double benchmark( int iterations, int len ) {
+static double benchmark1( int iterations, int len ) {
 	stdlib_complex64_t alpha;
 	float x[ len*2 ];
 	double elapsed;
@@ -122,6 +122,40 @@ static double benchmark( int iterations, int len ) {
 	return elapsed;
 }
 
+/**
+* Runs a benchmark.
+*
+* @param iterations   number of iterations
+* @param len          array length
+* @return elapsed time in seconds
+*/
+static double benchmark2( int iterations, int len ) {
+	stdlib_complex64_t alpha;
+	float x[ len*2 ];
+	double elapsed;
+	double t;
+	int i;
+
+	alpha = stdlib_complex64( 1.0f, 0.0f );
+	for ( i = 0; i < len*2; i += 2 ) {
+		x[ i ] = ( rand_float()*2.0f ) - 1.0f;
+		x[ i+1 ] = ( rand_float()*2.0f ) - 1.0f;
+	}
+	t = tic();
+	for ( i = 0; i < iterations; i++ ) {
+		c_cfill_ndarray( len, alpha, (stdlib_complex64_t *)x, 1, 0 );
+		if ( x[ 0 ] != x[ 0 ] ) {
+			printf( "should not return NaN\n" );
+			break;
+		}
+	}
+	elapsed = tic() - t;
+	if ( x[ 0 ] != x[ 0 ] ) {
+		printf( "should not return NaN\n" );
+	}
+	return elapsed;
+}
+
 /**
 * Main execution sequence.
 */
@@ -144,7 +178,14 @@ int main( void ) {
 		for ( j = 0; j < REPEATS; j++ ) {
 			count += 1;
 			printf( "# c::%s:len=%d\n", NAME, len );
-			elapsed = benchmark( iter, len );
+			elapsed = benchmark1( iter, len );
+			print_results( iter, elapsed );
+			printf( "ok %d benchmark finished\n", count );
+		}
+		for ( j = 0; j < REPEATS; j++ ) {
+			count += 1;
+			printf( "# c::%s:ndarray:len=%d\n", NAME, len );
+			elapsed = benchmark2( iter, len );
 			print_results( iter, elapsed );
 			printf( "ok %d benchmark finished\n", count );
 		}

lib/node_modules/@stdlib/blas/ext/base/cfill/docs/repl.txt

@@ -1,5 +1,5 @@
 
-{{alias}}( N, alpha, x, stride )
+{{alias}}( N, alpha, x, strideX )
     Fills a single-precision complex floating-point strided array with a
     specified scalar constant.
 
@@ -22,7 +22,7 @@
     x: Complex64Array
         Input array.
 
-    stride: integer
+    strideX: integer
         Index increment.
 
     Returns
@@ -74,7 +74,7 @@
     -5.0
 
 
-{{alias}}.ndarray( N, alpha, x, stride, offset )
+{{alias}}.ndarray( N, alpha, x, strideX, offsetX )
     Fills a single-precision complex floating-point strided array with a
     specified scalar constant using alternative indexing semantics.
 
@@ -93,10 +93,10 @@
     x: Complex64Array
         Input array.
 
-    stride: integer
+    strideX: integer
         Index increment.
 
-    offset: integer
+    offsetX: integer
         Starting index.
 
     Returns

lib/node_modules/@stdlib/blas/ext/base/cfill/docs/types/index.d.ts

@@ -33,7 +33,7 @@ interface Routine {
 	* @param N - number of indexed elements
 	* @param alpha - scalar constant
 	* @param x - input array
-	* @param stride - stride length
+	* @param strideX - stride length
 	* @returns input array
 	*
 	* @example
@@ -59,16 +59,16 @@ interface Routine {
 	* var im = imagf( y );
 	* // returns 10.0
 	*/
-	( N: number, alpha: Complex64, x: Complex64Array, stride: number ): Complex64Array;
+	( N: number, alpha: Complex64, x: Complex64Array, strideX: number ): Complex64Array;
 
 	/**
 	* Fills a single-precision complex floating-point strided array with a specified scalar constant.
 	*
 	* @param N - number of indexed elements
 	* @param alpha - scalar constant
 	* @param x - input array
-	* @param stride - stride length
-	* @param offset - starting index
+	* @param strideX - stride length
+	* @param offsetX - starting index
 	* @returns input array
 	*
 	* @example
@@ -94,7 +94,7 @@ interface Routine {
 	* var im = imagf( y );
 	* // returns 10.0
 	*/
-	ndarray( N: number, alpha: Complex64, x: Complex64Array, stride: number, offset: number ): Complex64Array;
+	ndarray( N: number, alpha: Complex64, x: Complex64Array, strideX: number, offsetX: number ): Complex64Array;
 }
 
 /**
@@ -103,7 +103,7 @@ interface Routine {
 * @param N - number of indexed elements
 * @param alpha - scalar constant
 * @param x - input array
-* @param stride - index increment
+* @param strideX - index increment
 * @returns input array
 *
 * @example

lib/node_modules/@stdlib/blas/ext/base/cfill/examples/c/example.c

@@ -31,10 +31,10 @@ int main() {
 	const int N = 4;
 
 	// Specify a stride:
-	const int stride = 1;
+	const int strideX = 1;
 
 	// Fill the array:
-	c_cfill( N, alpha, (stdlib_complex64_t *)x, stride );
+	c_cfill( N, alpha, (stdlib_complex64_t *)x, strideX );
 
 	// Print the result:
 	for ( int i = 0; i < 8; i++ ) {

lib/node_modules/@stdlib/blas/ext/base/cfill/examples/index.js

@@ -18,16 +18,15 @@
 
 'use strict';
 
-var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
-var filledarrayBy = require( '@stdlib/array/filled-by' );
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var Complex64Array = require( '@stdlib/array/complex64' );
 var Complex64 = require( '@stdlib/complex/float32/ctor' );
 var cfill = require( './../lib' );
 
-function rand() {
-	return new Complex64( discreteUniform( 0, 10 ), discreteUniform( -5, 5 ) );
-}
-
-var x = filledarrayBy( 10, 'complex64', rand );
+var xbuf = discreteUniform( 20, -100, 100, {
+	'dtype': 'float32'
+});
+var x = new Complex64Array( xbuf.buffer );
 var alpha = new Complex64( 10.0, 10.0 );
 
 cfill( x.length, alpha, x, 1 );