refactor: use common implementation and document C API

Author: kgryte

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

@@ -179,6 +179,113 @@ console.log( y );
 
 <!-- /.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/srot.h"
+```
+
+#### c_srot( N, \*X, strideX, \*Y, strideY, c, s )
+
+Applies a plane rotation.
+
+```c
+float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f };
+float y[] = { 6.0f, 7.0f, 8.0f, 9.0f, 10.0f };
+
+c_drot( 5, x, 1, y, 1, 0.8f, 0.6f );
+```
+
+The function accepts the following arguments:
+
+-   **N**: `[in] CBLAS_INT` number of indexed elements.
+-   **X**: `[inout] float*` first input array.
+-   **strideX**: `[in] CBLAS_INT` index increment for `X`.
+-   **Y**: `[inout] float*` second input array.
+-   **strideY**: `[in] CBLAS_INT` index increment for `Y`.
+-   **c**: `[in] float` cosine of the angle of rotation.
+-   **s**: `[in] float` sine of the angle of rotation.
+
+```c
+void c_drot( const CBLAS_INT N, float *X, const CBLAS_INT strideX, float *Y, const CBLAS_INT strideY, const float c, const float s );
+```
+
+</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/drot.h"
+#include <stdio.h>
+
+int main( void ) {
+    // Create strided arrays:
+    float x[] = { 1.0f, 2.0f, 3.0f, 4.0f, 5.0f };
+    float y[] = { 6.0f, 7.0f, 8.0f, 9.0f, 10.0f };
+
+    // Specify the number of elements:
+    const int N = 5;
+
+    // Specify stride lengths:
+    const int strideX = 1;
+    const int strideY = 1;
+
+    // Specify angle of rotation:
+    const float c = 0.8f;
+    const float s = 0.6f;
+
+    // Apply plane rotation:
+    c_drot( N, x, strideX, y, strideY, c, s );
+
+    // Print the result:
+    for ( int i = 0; i < 5; i++ ) {
+        printf( "x[ %i ] = %f, y[ %i ] = %f\n", i, x[ i ], i, y[ i ] );
+    }
+}
+```
+
+</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/base/srot/lib/ndarray.js

@@ -18,6 +18,11 @@
 
 'use strict';
 
+// MODULES //
+
+var f32 = require( '@stdlib/number/float64/base/to-float32' );
+
+
 // MAIN //
 
 /**
@@ -53,12 +58,13 @@ function srot( N, x, strideX, offsetX, y, strideY, offsetY, c, s ) {
 	if ( N <= 0 ) {
 		return y;
 	}
+	c = f32( c );
+	s = f32( s );
 	ix = offsetX;
 	iy = offsetY;
-
 	for ( i = 0; i < N; i++ ) {
-		tmp = ( c * x[ ix ] ) + ( s * y[ iy ] );
-		y[ iy ] = ( c * y[ iy ] ) - ( s * x[ ix ] );
+		tmp = f32( c * x[ ix ] ) + f32( s * y[ iy ] );
+		y[ iy ] = f32( c * y[ iy ] ) - f32( s * x[ ix ] );
 		x[ ix ] = tmp;
 		ix += strideX;
 		iy += strideY;

lib/node_modules/@stdlib/blas/base/srot/lib/srot.js

@@ -41,22 +41,16 @@ var ndarray = require( './ndarray.js' );
 * @example
 * var Float32Array = require( '@stdlib/array/float32' );
 *
-* var x = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );
-* var y = new Float32Array( [ 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 ] );
+* var x = new Float32Array( [ 1.0, 2.0, 3.0, 4.0, 5.0 ] );
+* var y = new Float32Array( [ 6.0, 7.0, 8.0, 9.0, 10.0 ] );
 *
-* srot( 3, x, 2, y, 2, 0.8, 0.6 );
-* // x => <Float32Array>[ 5.0, 2.0, ~7.8, 4.0, ~10.6, 6.0 ]
-* // y => <Float32Array>[ 5.0, 8.0, ~5.4, 10.0, ~5.8, 12.0 ]
+* srot( x.length, x, 1, y, 1, 0.8, 0.6 );
+* // x => <Float32Array>[ ~4.4, ~5.8, ~7.2, ~8.6, 10.0 ]
+* // y => <Float32Array>[ ~4.2, 4.4, 4.6, 4.8, 5.0 ]
 */
 function srot( N, x, strideX, y, strideY, c, s ) {
-	var ix;
-	var iy;
-
-	if ( N <= 0 ) {
-		return y;
-	}
-	ix = stride2offset( N, strideX );
-	iy = stride2offset( N, strideY );
+	var ix = stride2offset( N, strideX );
+	var iy = stride2offset( N, strideY );
 	return ndarray( N, x, strideX, ix, y, strideY, iy, c, s );
 }