feat: add C implementation for stats/base/dists/binomial/kurtosis

lib/node_modules/@stdlib/math/base/napi/binary/README.md

@@ -331,6 +331,46 @@ The function accepts the following arguments:
 void stdlib_math_base_napi_di_d( napi_env env, napi_callback_info info, double (*fcn)( double, int32_t ) );
 ```
 
+#### stdlib_math_base_napi_id_d( env, info, fcn )
+
+Invokes a binary function accepting a signed 32-bit integer and a double-precision floating-point number and returning a double-precision floating-point number.
+
+```c
+#include <node_api.h>
+#include <stdint.h>
+
+// ...
+
+static double mul( const int32_t x, const double y ) {
+    return x * y;
+}
+
+// ...
+
+/**
+* Receives JavaScript callback invocation data.
+*
+* @param env    environment under which the function is invoked
+* @param info   callback data
+* @return       Node-API value
+*/
+napi_value addon( napi_env env, napi_callback_info info ) {
+    return stdlib_math_base_napi_id_d( env, info, mul );
+}
+
+// ...
+```
+
+The function accepts the following arguments:
+
+-   **env**: `[in] napi_env` environment under which the function is invoked.
+-   **info**: `[in] napi_callback_info` callback data.
+-   **fcn**: `[in] double (*fcn)( int32_t, double )` binary function.
+
+```c
+void stdlib_math_base_napi_id_d( napi_env env, napi_callback_info info, double (*fcn)( int32_t, double ) );
+```
+
 #### stdlib_math_base_napi_ii_i( env, info, fcn )
 
 Invokes a binary function accepting and returning signed 32-bit integers.
@@ -820,6 +860,29 @@ The macro expects the following arguments:
 
 When used, this macro should be used **instead of** `NAPI_MODULE`. The macro includes `NAPI_MODULE`, thus ensuring Node-API module registration.
 
+#### STDLIB_MATH_BASE_NAPI_MODULE_ID_D( fcn )
+
+Macro for registering a Node-API module exporting an interface invoking a binary function accepting a signed 32-bit integer and a double-precision floating-point number and returning a double-precision floating-point number.
+
+```c
+#include <stdint.h>
+
+static double mul( const int32_t x, const double y ) {
+    return x * y;
+}
+
+// ...
+
+// Register a Node-API module:
+STDLIB_MATH_BASE_NAPI_MODULE_ID_D( mul );
+```
+
+The macro expects the following arguments:
+
+-   **fcn**: `double (*fcn)( int32_t, double )` binary function.
+
+When used, this macro should be used **instead of** `NAPI_MODULE`. The macro includes `NAPI_MODULE`, thus ensuring Node-API module registration.
+
 #### STDLIB_MATH_BASE_NAPI_MODULE_FI_F( fcn )
 
 Macro for registering a Node-API module exporting an interface invoking a binary function accepting a single-precision floating-point number and a signed 32-bit integer and returning a single-precision floating-point number.

lib/node_modules/@stdlib/math/base/napi/binary/include/stdlib/math/base/napi/binary.h

@@ -342,6 +342,48 @@
 	};                                                                         \
 	NAPI_MODULE( NODE_GYP_MODULE_NAME, stdlib_math_base_napi_di_d_init )
 
+/**
+* Macro for registering a Node-API module exporting an interface invoking a binary function accepting a signed 32-bit integer and a double-precision floating-point number and returning a double-precision floating-point number.
+*
+* @param fcn   binary function
+*
+* @example
+* #include <stdint.h>
+*
+* static double mul( const int32_t n, const double x ) {
+*     return x * n;
+* }
+*
+* // ...
+*
+* // Register a Node-API module:
+* STDLIB_MATH_BASE_NAPI_MODULE_ID_D( mul );
+*/
+#define STDLIB_MATH_BASE_NAPI_MODULE_ID_D( fcn )                               \
+	static napi_value stdlib_math_base_napi_id_d_wrapper(                      \
+		napi_env env,                                                          \
+		napi_callback_info info                                                \
+	) {                                                                        \
+		return stdlib_math_base_napi_id_d( env, info, fcn );                   \
+	};                                                                         \
+	static napi_value stdlib_math_base_napi_id_d_init(                         \
+		napi_env env,                                                          \
+		napi_value exports                                                     \
+	) {                                                                        \
+		napi_value fcn;                                                        \
+		napi_status status = napi_create_function(                             \
+			env,                                                               \
+			"exports",                                                         \
+			NAPI_AUTO_LENGTH,                                                  \
+			stdlib_math_base_napi_id_d_wrapper,                                \
+			NULL,                                                              \
+			&fcn                                                               \
+		);                                                                     \
+		assert( status == napi_ok );                                           \
+		return fcn;                                                            \
+	};                                                                         \
+	NAPI_MODULE( NODE_GYP_MODULE_NAME, stdlib_math_base_napi_id_d_init )
+
 /**
 * Macro for registering a Node-API module exporting an interface invoking a binary function accepting a single-precision floating-point number and a signed 32-bit integer and returning a single-precision floating-point number.
 *
@@ -690,6 +732,11 @@ napi_value stdlib_math_base_napi_cc_c( napi_env env, napi_callback_info info, st
 */
 napi_value stdlib_math_base_napi_di_d( napi_env env, napi_callback_info info, double (*fcn)( double, int32_t ) );
 
+/**
+* Invokes a binary function accepting a signed 32-bit integer and a double-precision floating-point number and returning a double-precision floating-point number.
+*/
+napi_value stdlib_math_base_napi_id_d( napi_env env, napi_callback_info info, double (*fcn)( int32_t, double ) );
+
 /**
 * Invokes a binary function accepting signed 32-bit integers and returning a double-precision floating-point number.
 */

lib/node_modules/@stdlib/math/base/napi/binary/src/main.c

@@ -524,6 +524,68 @@ napi_value stdlib_math_base_napi_di_d( napi_env env, napi_callback_info info, do
 	return v;
 }
 
+/**
+* Invokes a binary function accepting a signed 32-bit integer and a double-precision floating-point number and returning a double-precision floating-point number.
+*
+* ## Notes
+*
+* -   This function expects that the callback `info` argument provides access to the following JavaScript arguments:
+*
+*     -   `x`: input value.
+*     -   `y`: input value.
+*
+* @param env    environment under which the function is invoked
+* @param info   callback data
+* @param fcn    binary function
+* @return       function return value as a Node-API double-precision floating-point number
+*/
+napi_value stdlib_math_base_napi_id_d( napi_env env, napi_callback_info info, double (*fcn)( int32_t, double ) ) {
+	napi_status status;
+
+	size_t argc = 2;
+	napi_value argv[ 2 ];
+	status = napi_get_cb_info( env, info, &argc, argv, NULL, NULL );
+	assert( status == napi_ok );
+
+	if ( argc < 2 ) {
+		status = napi_throw_error( env, NULL, "invalid invocation. Must provide two numbers." );
+		assert( status == napi_ok );
+		return NULL;
+	}
+
+	napi_valuetype vtype0;
+	status = napi_typeof( env, argv[ 0 ], &vtype0 );
+	assert( status == napi_ok );
+	if ( vtype0 != napi_number ) {
+		status = napi_throw_type_error( env, NULL, "invalid argument. First argument must be a number." );
+		assert( status == napi_ok );
+		return NULL;
+	}
+
+	napi_valuetype vtype1;
+	status = napi_typeof( env, argv[ 1 ], &vtype1 );
+	assert( status == napi_ok );
+	if ( vtype1 != napi_number ) {
+		status = napi_throw_type_error( env, NULL, "invalid argument. Second argument must be a number." );
+		assert( status == napi_ok );
+		return NULL;
+	}
+
+	int32_t x;
+	status = napi_get_value_int32( env, argv[ 0 ], &x );
+	assert( status == napi_ok );
+
+	double y;
+	status = napi_get_value_double( env, argv[ 1 ], &y );
+	assert( status == napi_ok );
+
+	napi_value v;
+	status = napi_create_double( env, fcn( x, y ), &v );
+	assert( status == napi_ok );
+
+	return v;
+}
+
 /**
 * Invokes a binary function accepting signed 32-bit integers and returning a double-precision floating-point number.
 *

lib/node_modules/@stdlib/stats/base/dists/binomial/kurtosis/README.md

@@ -141,6 +141,103 @@ for ( i = 0; i < 10; 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/stats/base/dists/binomial/kurtosis.h"
+```
+
+#### stdlib_base_dists_binomial_kurtosis( n, p )
+
+Returns the [excess kurtosis][kurtosis] of a [binomial][binomial-distribution] distribution with number of trials `n` and success probability `p`.
+
+```c
+double out = stdlib_base_dists_binomial_kurtosis( 100, 0.1 );
+// returns ~0.051
+```
+
+The function accepts the following arguments:
+
+-   **n**: `[in] int32_t` number of trials.
+-   **p**: `[in] double` success probability.
+
+```c
+double stdlib_base_dists_binomial_kurtosis( const int32_t n, const double p );
+```
+
+</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/stats/base/dists/binomial/kurtosis.h"
+#include "stdlib/math/base/special/ceil.h"
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+
+static double random_uniform( const double min, const double max ) {
+    double v = (double)rand() / ( (double)RAND_MAX + 1.0 );
+    return min + ( v * (max - min) );
+}
+
+int main( void ) {
+    int32_t n;
+    double p;
+    double y;
+    int i;
+
+    for ( i = 0; i < 25; i++ ) {
+        n = stdlib_base_ceil( random_uniform( 0.0, 100.0 ) );
+        p = random_uniform( 0.0, 1.0 );
+        y = stdlib_base_dists_binomial_kurtosis( n, p );
+        printf( "n: %d, p: %lf, Kurt(X;n,p): %lf\n", n, p, y );
+    }
+
+    return 0;
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+</section>
+
+<!-- /.c -->
+
 <!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
 
 <section class="references">

lib/node_modules/@stdlib/stats/base/dists/binomial/kurtosis/benchmark/benchmark.js

@@ -22,6 +22,7 @@
 
 var bench = require( '@stdlib/bench' );
 var ceil = require( '@stdlib/math/base/special/ceil' );
+var Float64Array = require( '@stdlib/array/float64' );
 var randu = require( '@stdlib/random/base/randu' );
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
 var pkg = require( './../package.json' ).name;
@@ -31,16 +32,23 @@ var kurtosis = require( './../lib' );
 // MAIN //
 
 bench( pkg, function benchmark( b ) {
+	var len;
 	var n;
 	var p;
 	var y;
 	var i;
 
+	len = 100;
+	n = new Float64Array( len );
+	p = new Float64Array( len );
+	for ( i = 0; i < len; i++ ) {
+		n[ i ] = ceil( randu() * 100.0 );
+		p[ i ] = randu();
+	}
+
 	b.tic();
 	for ( i = 0; i < b.iterations; i++ ) {
-		n = ceil( randu()*100.0 );
-		p = randu();
-		y = kurtosis( n, p );
+		y = kurtosis( n[ i%len ], p[ i%len ] );
 		if ( isnan( y ) ) {
 			b.fail( 'should not return NaN' );
 		}