feat: remove out keyword, add C implementation and addon to cpolar API

lib/node_modules/@stdlib/math/base/special/cpolar/README.md

@@ -18,9 +18,9 @@ limitations under the License.
 
 -->
 
-# polar
+# cpolar
 
-> Compute the [absolute value][@stdlib/math/base/special/cabs] and [phase][@stdlib/math/base/special/cphase] of a complex number.
+> Compute the [absolute value][@stdlib/math/base/special/cabs] and [phase][@stdlib/math/base/special/cphase] of a double-precision complex floating-point number.
 
 <section class="intro">
 
@@ -36,26 +36,31 @@ limitations under the License.
 var cpolar = require( '@stdlib/math/base/special/cpolar' );
 ```
 
-#### cpolar( \[out,] re, im )
+#### cpolar( z )
 
-Computes the [absolute value][@stdlib/math/base/special/cabs] and [phase][@stdlib/math/base/special/cphase] of a complex number comprised of a **real** component `re` and an **imaginary** component `im`.
+Computes the [absolute value][@stdlib/math/base/special/cabs] and [phase][@stdlib/math/base/special/cphase] of a double-precision complex floating-point number.
 
 ```javascript
-var o = cpolar( 5.0, 3.0 );
+var Complex128 = require( '@stdlib/complex/float64' );
+
+var o = cpolar( new Complex128( 5.0, 3.0 ) );
 // returns [ ~5.83, ~0.5404 ]
 ```
 
-By default, the function returns real and imaginary components as a two-element `array`. To avoid unnecessary memory allocation, the function supports providing an output (destination) object.
+#### cpolar.assign( z, out, stride, offset )
+
+Computes the [absolute value][@stdlib/math/base/special/cabs] and [phase][@stdlib/math/base/special/cphase] of a double-precision complex floating-point number and assigns results to a provided output array.
 
 ```javascript
+var Complex128 = require( '@stdlib/complex/float64' );
 var Float64Array = require( '@stdlib/array/float64' );
 
 var out = new Float64Array( 2 );
 
-var o = cpolar( out, 5.0, 3.0 );
+var v = cpolar.assign( new Complex128( 5.0, 3.0 ), out, 1, 0 );
 // returns <Float64Array>[ ~5.83, ~0.5404 ]
 
-var bool = ( o === out );
+var bool = ( v === out );
 // returns true
 ```
 
@@ -87,7 +92,7 @@ for ( i = 0; i < 100; i++ ) {
     re = round( randu()*100.0 ) - 50.0;
     im = round( randu()*100.0 ) - 50.0;
     z = new Complex128( re, im );
-    o = cpolar( real(z), imag(z) );
+    o = cpolar( z );
     z = z.toString();
     console.log( 'abs(%s) = %d. arg(%s) = %d', z, o[0], z, o[1] );
 }
@@ -97,6 +102,110 @@ for ( i = 0; i < 100; i++ ) {
 
 <!-- /.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/math/base/special/cpolar.h"
+```
+
+#### stdlib_base_cpolar( z, cabs, cphase )
+
+Computes the [absolute value][@stdlib/math/base/special/cabs] and [phase][@stdlib/math/base/special/cphase] of a double-precision complex floating-point number.
+
+```c
+#include "stdlib/complex/float64.h"
+#include "stdlib/complex/real.h"
+#include "stdlib/complex/imag.h"
+
+stdlib_complex128_t z = stdlib_complex128( 5.0, 3.0 );
+double cabs;
+double cphase;
+stdlib_base_cpolar( z, &cabs, &cphase );
+```
+
+The function accepts the following arguments:
+
+-   **z**: `[in] stdlib_complex128_t` input value.
+-   **cabs**: `[out] double*` destination for the absolute value.
+-   **cphase**: `[out] double*` destination for the phase value in radians.
+
+```c
+double stdlib_base_cpolar( const stdlib_complex128_t z, double *cabs, double *cphase );
+```
+
+</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/math/base/special/cpolar.h"
+#include "stdlib/complex/float64.h"
+#include "stdlib/complex/reim.h"
+#include <stdio.h>
+
+int main( void ) {
+    const stdlib_complex128_t x[] = {
+        stdlib_complex128( 3.14, 1.0 ),
+        stdlib_complex128( -3.14, -1.0 ),
+        stdlib_complex128( 0.0, 0.0 ),
+        stdlib_complex128( 0.0/0.0, 0.0/0.0 )
+    };
+
+    double cphase;
+    double cabs;
+    double re;
+    double im;
+    int i;
+    for ( i = 0; i < 12; i++ ) {
+        stdlib_base_cpolar( x[i], &cabs, &cphase );
+        stdlib_reim( x[i], &re, &im );
+        printf( "cpolar(%lf + %lfi) => cabs: %lf, cphase: %lf\n", re, im, cabs, cphase );
+    }
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+</section>
+
+<!-- /.c -->
+
 <!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
 
 <section class="related">
@@ -122,10 +231,6 @@ for ( i = 0; i < 100; i++ ) {
 
 <!-- <related-links> -->
 
-[@stdlib/math/base/special/cabs]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/cabs
-
-[@stdlib/math/base/special/cphase]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/cphase
-
 <!-- </related-links> -->
 
 </section>

lib/node_modules/@stdlib/math/base/special/cpolar/benchmark/benchmark.js

@@ -21,25 +21,28 @@
 // MODULES //
 
 var bench = require( '@stdlib/bench' );
-var randu = require( '@stdlib/random/base/randu' );
+var uniform = require( '@stdlib/random/base/uniform' );
 var isArray = require( '@stdlib/assert/is-array' );
+var Complex128 = require( '@stdlib/complex/float64' );
 var pkg = require( './../package.json' ).name;
 var cpolar = require( './../lib' );
 
 
 // MAIN //
 
 bench( pkg, function benchmark( b ) {
-	var re;
-	var im;
+	var values;
 	var y;
 	var i;
 
+	values = [
+		new Complex128( uniform( -500.0, 500.0 ), uniform( -500.0, 500.0 ) ),
+		new Complex128( uniform( -500.0, 500.0 ), uniform( -500.0, 500.0 ) )
+	];
+
 	b.tic();
 	for ( i = 0; i < b.iterations; i++ ) {
-		re = ( randu()*1000.0 ) - 500.0;
-		im = ( randu()*1000.0 ) - 500.0;
-		y = cpolar( re, im );
+		y = cpolar( values[ i%values.length ] );
 		if ( y.length === 0 ) {
 			b.fail( 'should not be empty' );
 		}
@@ -52,21 +55,22 @@ bench( pkg, function benchmark( b ) {
 	b.end();
 });
 
-bench( pkg+'::memory_reuse', function benchmark( b ) {
-	var out;
-	var re;
-	var im;
+bench( pkg+':assign', function benchmark( b ) {
+	var values;
 	var y;
 	var i;
 
-	out = new Array( 2 );
+	values = [
+		new Complex128( uniform( -500.0, 500.0 ), uniform( -500.0, 500.0 ) ),
+		new Complex128( uniform( -500.0, 500.0 ), uniform( -500.0, 500.0 ) )
+	];
+
+	y = [ 0.0, 0.0 ];
 
 	b.tic();
 	for ( i = 0; i < b.iterations; i++ ) {
-		re = ( randu()*1000.0 ) - 500.0;
-		im = ( randu()*1000.0 ) - 500.0;
-		y = cpolar( out, re, im );
-		if ( y.length === 0 ) {
+		cpolar.assign( values[ i%values.length ], y, 1, 0 );
+		if ( y[ 0 ] !== y[ 0 ] || y[ 1 ] !== y[ 1 ] ) {
 			b.fail( 'should not be empty' );
 		}
 	}

lib/node_modules/@stdlib/math/base/special/cpolar/benchmark/benchmark.native.js

@@ -0,0 +1,65 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2023 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/base/uniform' );
+var isArray = require( '@stdlib/assert/is-array' );
+var Complex128 = require( '@stdlib/complex/float64' );
+var tryRequire = require( '@stdlib/utils/try-require' );
+var pkg = require( './../package.json' ).name;
+
+
+// VARIABLES //
+
+var cpolar = tryRequire( resolve( __dirname, './../lib/native.js' ) );
+var opts = {
+	'skip': ( cpolar instanceof Error )
+};
+
+
+// MAIN //
+
+bench( pkg+'::native', opts, function benchmark( b ) {
+	var values;
+	var y;
+	var i;
+
+	values = [
+		new Complex128( uniform( -500.0, 500.0 ), uniform( -500.0, 500.0 ) ),
+		new Complex128( uniform( -500.0, 500.0 ), uniform( -500.0, 500.0 ) )
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		y = cpolar( values[ i%values.length ] );
+		if ( y.length === 0 ) {
+			b.fail( 'should not be empty' );
+		}
+	}
+	b.toc();
+	if ( !isArray( y ) ) {
+		b.fail( 'should return an array' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});